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Snap-Master User's Manual

1. 10 10 10 0 Time Sec 2 Time Sec 2 0 Time Sec 2 11 11 97 9 52 47 AM Figure 12 14 Display of Addition Equation Inputs and Result When you Start the instrument you should see the results This Display window shows three Y T plots one each for AO Al and RO Notice that the channel label and units are included automatically in the plot of RO If you receive a message that says the Analysis equations must be checked before the instrument will run open the Analysis window and press the button The button says when the equations are correct Page 12 32 Snap Master User s Manual 12 5 Tutorial Performing A Block Average Building The Equation This tutorial uses two functions the Block and Average functions to obtain a new result By itself the Average function produces only a single point By including the Block function we can obtain an average for each block of points Analysis Untitled ols File Edi View Settings Builder Help eH amp lt Ee 58 j Z ox PO block 20 avg A0 n Run Comments Equation Definition Label Units Figure 12 15 Analysis Window with Block Average Equation 1 Position the selection box in the second row of the equation table 2 Press the button or select the Builder menu to open the Equation Builder
2. aa peii US 11 10 97 11 4535 AM rr Figure 3 38 Display Page 1 With Figure 3 39 Display Page 2 With Custom Two Rows Title Page 3 38 Snap Master User s Manual 3 6 Tutorial Using Cursors And Markers Placing A Cursor Cursors and markers are a quick way to get quantitative data from the Display window as well as mark specific points of interest In this section we will place a cursor to read the data values from the plot and we will also find the slope between two points Placing a markers uses the same method as placing a cursor 1 Change the Display Page back to Page 1 For simplicity we will place the cursor on the Y T plot of channel AO Assuming you have followed the tutorials to this point this is the upper plot on Display Page 1 2 Press the button or select the Cursor menu New Cursor command After you press the button the Cursor Data table appears By default the table appears in the Display window itself If you want it in its own window right click over the table and select the Toggle Location menu command 3 Move the mouse pointer over the upper plot and press the right mouse button When you move the mouse pointer over a plot the mouse pointer changes to When you click on the mouse button a cursor is placed at the corresponding X axis location on the channel and the mouse pointer returns to the standard pointer You do not have to b
3. S0 find AD lt 0 Equation Definition Label Units ios neers A OUR VOE a PO block 20j avaiAQ 0z find AD lt 0 i Figure 12 20 Analysis Window with Find Equation 1 Position the selection box in the third row of the equation table 2 Press the button or select the Builder menu to open the Equation Builder Analysis and Frequency Analysis Page 12 35 Analysis Equation Builder Line 3 Equation so find AO lt 0 a Quick Functions e z Pea or e Lr a A05 block range Define Function Builders Category Trigonometric 4 Function And Time s Or Syntax find argumentl Description Returns the frame time of the first point in argument which is True equal to or greater than 1 Argument usually contains a comparison i e A05 cereus Cancel Help Next Line gt gt Figure 12 21 Equation Builder with Find Equation 3 Position the mouse pointer over the Equation edit control and press the right mouse button to open the On Screen Keypad 4 Select the Channel radio button 5 Select the letter S from the list box The Find function returns a single point so the frame length of our result is one point For this reason we will use a different element letter for this result channel 6 Press the number 0 on the On Screen Keypad 7 Press the OK button to close the On Screen Keypad 8 Click on the B button 9 Select
4. Sensor Calibration History Delete Calibration 01284 532 Cal Factor ee Input Input Eng per Outpd Date Min Max _ Units Min Max 204532 11 10 97 421000 0001 1 479 772 3178490 gpm 1140 7 550 284532 11 13 86 421000 0 000 4 3 72 3l 849Digpm 1 140 7 550 Figure 7 2 7 Calibration History Table The Sensor Calibration History table contains the list of dates when a sensor was calibrated To open the table select the Calibration History button e When you change the Last Calibration Date a new entry is added to the Calibration History for that sensor using the current scaling values remember that the changes are saved in the database when you move the selection box off the row of the sensor Only one calibration per day is recorded The Calibration History table is sorted according to the Last Date column with the most recent calibration dates listed at the top of the table Signal Conditioning Database Configuration Page 7 7 Database Configuration Network Settings Resource Limits s PARADOX NET Path C Record Buffers 64 Record Locks 64 Le per table Network Type Novell NetWare x Open Files 64 I Share Local Tables Swap Buffer Size 64 KB Cancel Help 7 8 Database Configuration The Database Configuration dialog box changes the network and resource settings for the Sensor database These settings are stored in
5. M 11 3 11 3 Tutorial Outputting Analog Data eseseeeessoessssosssssesssssesessoesesosesesosesesosesesocesssocssssoessssesssssesesssesesosesesosesesosesesossse 11 4 11 4 Tutorial Outputting Digital Data Lee esee eese eee e eese e eerte esee enne tensa sesta asset toss sett es sese tease estesa eset enses se tnaeue 11 7 11 1 Analog Output D A n The D A element converts digital information from Snap Master into an analog signal using digital to analog hardware Snap Master allows you to use multiple D A devices in an instrument This hardware must be properly configured in both hardware and software for proper operation Please refer to the hardware documentation for information on its features and its use with Snap Master D A Settings D A Settings r Pacing Channel Assignments O O Type Hardware z A0 Location C Internal C External co ut Inactive I Driving Channel A0 zl j s Available 0 E Channels 1 T 2 Output Rate Default wem m Output Ranges C Manual 100 Hz _Dutput Ranges Device aca Slot 3 DDA4 F z c ns 1 Heck Em Status Messages C of Points 200 Configuration 7 Stop On Error Cancel Help Figure 11 1 D A Settings Pacing Type Software pacing relies on the computer s timer to determine when to output a new data point which is limited to around 20 times per s
6. EE 15 2 Tutorial Relay i ssssscicsessssesevancscsessssessusnesssesonseseconnsesavoasessatassessuesssessodessesusewsdcaseusssesatsessusatsesvsassteuesaseseuessesssvosseseuescse E 15 3 Thermocouple Linearization ccccssccsssscscsscsseccsscscescscsscsssscsssssscccesssscccssssscssesssccsssssscsssessscsssssscssssssscsssssssssees 12 7 7 15 4 Tutorial Thermocouple Linearization 4 eee eee ee eese nenne eene een sane s sees sess sess sse ens sess sess se ssseesnscessssessee 1278 15 5 Smoothing eee e eee eee Leere esee eerte esee een assets asse E A sesso EEEE esee ense see soss sse seoseseesessesesseseeeessess 127 12 15 6 Tutorial Smoothing eere eee eee eones oa oS EERE SE EEn EE E e sos se sess esses a 157 13 15 7 Histogram 14 eere esee ee eese eese eene netten esset enses esteso eset ens esee son sese senso E T sse ens esee sons esee soss E see sesseseseseeeeseese 127 17 15 8 Tutorial Histogram sscssssccscsescccvsacsecsesssssoessecssevoadsasscoussvsecessessscccecsenacsscouasceedauacsedsesacscesesassedevsusseosoansssveassseacensesesess LO L9 15 9 MUItiF Tame REP LOU 2D 15 10 Tutorial MultiFrame sssrin ensins enas o a a e oaa aaa a 12722 The elements described in this chapter are designed for specialized functions usually a special data analysis While these elements ma
7. Figure 15 4 Wave Generator Settings 1 Open the Wave Generator Settings table 2 Position the selection box in the first row Waveform column and select Ramp from the drop down list By default this creates a ramp which rises from 0 to 5 volts 3 Activate the channel by selecting the first row Active column and selecting Yes from the drop down list 4 Close the Wave Generator element by selecting the File menu Close Wave Generator command Utility Elements Setting Up The Relay Specifying The Auto Toggle Settings Page 15 5 1 Open the Relay Settings dialog box by double clicking on the Relay element Relay Settings r Configuration O Channel List Driving Channel A0 Voltage REEE Frame Settings T Use Defaults Sample Rate 1000 Hz Duration fs Sec Auto Toggle Channel Value C s of Points 500 Iv Status Messages Lox ce we Figure 15 5 Relay Settings 2 Set the Driving Channel to AO This lets us select any channels with the element letter A in the Channel list 3 Turn off the Use Defaults checkbox For our example we are only going to grab a small part of the waveform to illustrate the Relay element s ability to extract chunks of data 4 Set the Duration to 0 5 seconds 5 Select AO from the channel list Only channels that are highlighted in the Channel List are passed once the Relay element is activated 1 Press the Aut
8. Cancel Help Figure 13 2 Command Settings Determines how often the Command element executes the equations in the equation table Because there is no accompanying Frame Length setting the Command element is not frame based and treats all data as one continuous frame The maximum Decision Rate is determined by the overall speed of your computer and the complexity of the equations being processed Typically the maximum Decision Rate for the Command element is 100 Hz In addition the Decision Rate must be greater than 0 Sets the starting value of any state variable in the equation table State variables are used to keep track of additional data not available from data channels The default starting value for each state variable is 0 unless set to something else in this table Command Page 13 3 13 2 Command Equations When arranging the contents of the Command equation table Subroutines always come before the main body of equations The equation table is arranged as follows Description Equation Table Definitions Subroutine Sub SubRoutinel statements End Sub Subroutine Sub SubRoutine2 statements End Sub Main Text If Condition 1 Then True Action List 1 End If If Condition 2 Then True Action List 2 Else False Action List 2 End If The basic format for a Command element statement uses the following convention IF Comparison THEN True Action List ELSE False Action List END IF At
9. cereis sees eese eene een setas etna etna stones essa sensa etes s esos sse sns se sns se sense riasso teasers Om T Command Bar ined INN dae ocean sae aa Be dave EE Table Columns 3 E eite iot i ree ete ve geo t e pee e ee e Ee eg eee Ee P e ee ve oue Dialog Interfaces PH EE S a 8 2 Menu Commands Edit Metu ra eninaReU eI RB RERO RERBA S OU Gr Settings Menu nx vereint tue ed oe eoe ed e coii e heres Device Menu eA AT UIN BINGO RENTRER CRN Digital MW E ES USE Digital In Settings idee dee ned em ee dap pa Gans ede eter 8 13 Page vi Snap Master User s Manual 8 4 Tutorial Acquiring Analog Data ssccsscsssccsscsccssscsesssscscccssscscsssscsesssscscssssssessssscsesssscsessssees OP 13 Building the Instr ment teen eret dete ederet ete eee ene det eae eed e eder e edens Configuring the A D Element e eti epo Pe ade wish pind a cese Puede oe Running the Instr t ent uere rte e ert e e D E Ede e Te ERR Xe t eo re teta 8 5 Tutorial Using Triggers to Start Acquisition s Setting Up A THe 1 sei ott tpe snes poten eene E A ie e e edere aere Pe eter pep Running the Instrumentas siseses orne E conv E E E TE E scan censcctacubuccansevec HR ER EE LS 8 6 Tutorial Acquiring From Multiple Devices Building the Instr ment n aee deterrere terree tte der deerit eer leid redeo des Configuring the Input Elements
10. 12 4 File Meu iiec ep eie e tos EOD cas BEEEPRE EET Seva dregseua De ERR MIS ERR T tae aee Hee EREI De eoe 12 4 Builder Menp i e ertet au i EIE He Ete REED RR RUE 12 5 Set ngs Menuc inane ann en e eite mese andis c 12 7 j n 12 11 Arithimetic EUlctlons 1 1n ert erepto en beo eios FO Pee FORE e EEUU cuvsdens duke ERRARE ED TAT 12 12 Trigonometrie Functions 5 e Op a Ce erp e E oa e et 12 13 Calculus Funct ons 2 a ra E en I tete etn d e E OO SN eS 12 15 Statistical Eunctolis ub p E T 12 16 Logical Buncti ns ei neneRGhA eni eO CHO FERRO Ren E 12 18 Filters cess se cvca hist dacas eteasteee tsa Ave obeadenteds Parca patre e EO OR a er ren troi n 12 20 PAINE PUT COIORS a ete et ee RE PR e me euentu UE us 12 22 IbEEWIWCUD C MEO HET 12 22 Miscellaneous Functions n tete eei Be Ae et eee Lee eet I a tte eee eg 12 25 12 3 Equation Symtax ORC 12 26 Equation Format se iue eere reete tete e tette ette tet ep eco ede pedet regedit eed 12 27 User Defined Functions ipte tcd eee eee deese ene tee ede dre eee EE sua 12 27 12 4 Tutorial Adding Two Channels cete e eere esee crees ee eee eene eee tn aset tn esset ense sett es esee tense see tnus 12 28 Binlding the Instrument aee tenta Te etel iiber tee ep eeu Phe e EE Pedes 12 28 B nlding The Equation smet eener eee eere eee ie eee e emen eh 12 29 Running the Instrument cene edere ide eed ert ede e Pe eee EHE Ord t
11. Y Axis Settings Label fao vots Iv Show Label V Use Default p Axis r Major Divisions Type Linear CB 10x Major Divisions EE C Logarithmic C dB 20x Show As Horizontal Grid T Multiple Y Axes Curent Axis 1 zl C Tick Mark C None Location X 0 hd x Iv Show Axis Values dius Minimum and Maximum Iv Default Scale C All Major Divisions Minimum 10 Volts T Rotate Axis Values Maximum 10 Volts r Minor Divisions Minor Divisions 2 Format Default i d ngon TEM E w As jarl Significant Digits gt Chas Cancel Help Figure 3 4 Y Axis Settings Y vs T The Y axis Settings are similar to the X axis Settings and are accessed by double clicking on the Y axis area of the plot Most of the controls are the same except they control the Y axis Axis Type Determines if the axis scale is either Linear Logarithmic base 10 dB 10x or dB 20x These Decibel options create Bode plots by taking a Logarithmic plot and multiplying it by the scale factor shown either 10 or 20 The reason there are two options given is that different disciplines use different scaling factors for Bode plots Page 3 8 Channel Settings Snap Master User s Manual Multiple Y When selected you can overplot data from different channels with Axies different Y axis scales The number of axes in the list is the same as the maximum number of channels you can assign to a plot As you se
12. Page 8 2 Snap Master User s Manual Command Bar The Command Bar buttons unique to the A D element are Button Description fey Sets the sample rate frame length and number of frames AX Configures the trigger for the element os 1 Configures the input range for the element m Sets the amount of data retained in the element s buffer using the Memory Settings Cw dialog iiil Configures the base address interrupt and DMA settings of the hardware along with other physical jumper settings on the device Associates the installed hardware with Snap Master device numbers and shows an overview of the functionality of each installed device Table Columns The following columns are listed in the A D Settings table Channel The element letter and channel number of the acquired channel This column is not editable Some hardware has special rules about which channels you can acquire simultaneously For example some hardware requires that you sample all channels between the first and last channels selected no discontinuous channel numbers If the channels you specify are invalid for your hardware Snap Master automatically resets the selections to an appropriate choice For more information please refer to your hardware documentation Active Specifies if the data for the channel is sent out of the element Factor Specifies the multiplier for the channel to convert from volts to engineering units Also known as the m term for the linea
13. D3 Al End If If AO gt 40 Then D3 5 Else D3 5 End If A Command element result channel may be assigned to a digital or analog output channel with the Digital Out or D A elements respectively The element letter for the result channel must be the same as the element letter for the Command element itself statevar value Example If A0O gt 40 Then PeakCount PeakCount 1 Else PeakCount PeakCount End If State variables are used internally to the Command element to keep track of additional information not contained in other data channels As an action you can assign a state variable a new constant value the value of another state variable or perform a simple math function on a state variable Page 13 8 Stop Instrument Start Instrument Post Error Message Log Status Message DDE Poke Command Snap Master User s Manual Stop Example If AO gt 40 Then Stop End If The Stop command stops all elements except the Command element in the instrument The Command element continues processing all remaining statements in the equation table This lets you perform any final actions before the entire instrument stops Start instrument Example If A0 40 Then Start c sm defuser stage2 ins End If The Start command starts an instrument that is already open in the Snap Master workspace The Instrument reference uses the instrument s file name and it must be enclosed by pare
14. Turn the Display Command Bar on or off Turn the Status Bar on or off Turn the Display Scroll Bar on or off The Scroll Bar is used to pan through selected plots which are showing only a portion of the frame To select the plots controlled with the Scroll Bar highlight them by holding the CTRL key and clicking the mouse on the plots then use the Scroll Bar to scroll through the frame Each Display window has up to eight display pages which are accessed using the Pages menu The pages are configured using the Layout dialog which defines the plot types for each page For keyboard users pressing the ALT key along with a number changes to that page Page 3 18 Zoom In Zoom Out Snap Master User s Manual You can change the display page while the instrument is running but only the only data processed after the page change is plotted All plots on the current page are refreshed at the next frame boundary Lets you specify the exact area you want to zoom in on After you select a Zoom In mode the mouse pointer changes to To specify the area you want to zoom in on draw a rectangular box around the area by holding down the right mouse button and dragging the cursor with the mouse When you release the mouse button the minimum and maximum values for the axes you specified change to match the coordinates of the zoom region and the updated Display appears If the data does not redraw in the new axis ranges make sure you have Au
15. 3 6 Tutorial Using Cursors And Markers eere eee e eee eee ee ee een neenon aseo sse sn sse sns se ses sess see ens se sns se snsse sess eesseess cesse e 3 39 The Display element allows data from other elements to be viewed on the computer monitor Data from multiple channels and sources can be displayed simultaneously using overplotting or using multiple on screen axes In addition you can print the contents of the current display page or the entire desktop directly from this window The Display window appears on screen when you double click on the Display element icon or when you start the instrument 3 1 Display Window Command Bar E Display All Plo E E E e IN amp ll Ei 10 30 1 1 10 a 314 0 Time Sec 2 Time Sec 5 Voltage Voks 5 O Frequency Hz 10 O Frequency Hz 10 Digital Meter Ind nd 200 AD 4 999Volts Q ol AD 45 15 15 45 AD 5 iols Stopped instrament T 11 10 57 11 08 48 AMI Z Status Bar N Scroll Bar Used for Panning 10 Figure 3 1 Display Window Page 3 2 Snap Master User s Manual Command Bar The Display window s Command Bar contains the following special buttons for commonly used Display menu commands Ss 2 e 5 Description D Starts or Stops the instrument Changes
16. 4 Open the Disk Out dialog box by double clicking on the element Disk I O Running The Instrument Page 4 13 Disk Out Settings File Naming Method C Date And Tine C Numbered Sequence File Seed Cancel Ordinary Auto Overwrite File Name Directories Help tested eNsmMefuser Save Options File Comments Disk Out Defaults Throughput Tester File Format Drives Standard Binary dat x c hardly z Network ASCII File Export Number Format Decimal 6 4 Molts M Save Time Freq J Channel C Scientific x i esx Volts C Ensmeenng sooc 4 kVolts 52110282 dat aj a c 62511152 dat batch000 dat batch001 dat batch002 dat capture dat examb1 dat junk dat sm E defuser Figure 4 15 Disk Out Settings Dialog Box 5 Select the Ordinary File Naming Method Notice that when you select the Ordinary method the File Name edit control is activated 6 Enter the file name TEST in the File Name edit control You only need to do type the file name in the File Name field because Snap Master automatically adds the DAT extension The default directory for data files is the DEFUSER subdirectory of the SM directory 7 Click the OK button in the Disk Out dialog box 8 Save the instrument with the button or with the File menu Save command When you run the instrument you will see the data in the Display window while it is being saved Because the primary task of Sn
17. A DDE conversation uses three descriptors to identify the exact information to be transferred from the server These are the Service Name referred to as the Application in Windows 3 0 the Topic and the Item Once a DDE conversation has been initiated neither application can change the service name or topic but the conversation can consist of many different Items The Service Name is the name of the application that the client application is talking to Each server must have a unique application name and the server application must be running in order to complete the communication Example Service Names are Snap Master WinWord for Word for Windows and Excel for Excel The Topic is the subject within the conversation that is addressed by the client While each application only has one service name there can be more than one topic within the application Usually a topic is a file name document name DOC for Word worksheet name XLS for Excel or some other application specific string In Snap Master the topic is usually defined by the instrument name INS The last specification of the DDE conversation is the Item Just like a Service Name may have multiple Topics each Topic can have multiple Items An example of an Item is a cell reference within an Excel spreadsheet In Snap Master Items are subdivided by element and the Item includes the element letter a colon and the Item within the element For example the Item fo
18. NOTE The TCLinear element performs fifth order polynomials on each data point for the input channels Due to the complexity of these calculations keep the sample rate of the Driving Channel low when linearizing a large number of channels Performance will vary depending on the speed of your computer and the complexity of the instrument In the Thermocouple Linearization table you can edit any column except the Result Channel column which displays its column heading in red The following columns are in the table Result Channel Specifies the result channel for the linearization Active Specifies if the linearization is performed for the channel Input Channel Specifies the channel being linearized Type Specifies the thermocouple type of the input channel The available types are B E J K N R S and T Temperature Specifies the default temperature units for the result channel When you Units select an item in this column the Units column to the right changes automatically to the shorthand form for the units Label Specifies a unique channel name for the result channel Units Specifies the units for the result channel The contents of this cell will change when a selection is made in the Temperature Units column Page 15 8 CJC Settings Snap Master User s Manual Cold Junction Compensation Settings r Cold Junction Compensation CJC CIC Channel None zi Units c Method C Thermocoupl
19. The mathematical description for the Auto Power Spectrum is S avg S S where a is the channel listed in the Ch1 column S is the instantaneous amplitude spectrum of a and the S term is the complex conjugate of S The Auto Power Spectral Density function calculates the normalized power of a single channel Ch1 from the instantaneous amplitude spectrum output by the FFT algorithm Ch2 is not used for this function The result units are the square of the input units over Hertz such as volts Hz or psi2 Hz This function is similar to the Auto Power Spectrum except that the Auto Power Spectrum is normalized to make the measurement independent of the sampling rate and window bandwidth The difference between the Auto Power Spectral Density and the Auto Power Spectrum is that the spectral density is calculated per Hertz The normalization of the Auto Power Spectrum takes into account the effective bandwidth of window function used to compute the FFT By multiplying the spectral values by the inverse of the window period then the power spectrum is normalized to a per unit bandwidth This makes the measurements independent of the sample rate and window bandwidth Normalization is most useful for signals with strong sinusoidal components and random noise avg S S aa df where G is the instantaneous amplitude spectral density a is the channel listed in the Ch1 The mathematical description for the Auto Power Spectral Den
20. Analysis Equation Builder Line 2 Equation PO block 20 ava A0 Quick Functions gs x find or Jejmo Lr o A05 book range Define Function Builders Category Statistical 4 Function Range Syntax block ttPoints D verlap argumenti Description Separates argument into sections of length tf Points with optional Overlap and performs the contents of argument for each section The last point in the each section is the output of the Block function lt lt Previous Line Cancel Help Next Line gt gt Figure 12 16 Equation Builder with Block Average Equation 3 Position the mouse pointer over the Equation edit control and press the right mouse button to open the On Screen Keypad 4 Select the Channel radio button 5 Select the letter P from the list box Because the Block function produces different frame characteristics that our first equation we will use a different element letter for this result channel 6 Press the number 0 on the On Screen Keypad 7 Press the OK button to close the On Screen Keypad 8 Click on the button Analysis and Frequency Analysis Page 12 33 9 Click on the Data Ranges item in the Category list This shows the related functions in the Function list 10 Double click on the Block item in the Function list to open the Block Function Builder You may be wondering why the Block function is selected first and not the Average function T
21. F3 F4 ES instrument ChipNum CounterNum CountOn string Rising Edge Falling Edge instrument ChipNum CounterNum Gate string None Hi T C n 1 Hi Level n 1 Hi Level n 1 Hi Level n Lo Level n Hi Edge n Lo Edge n instrument ChipNum CounterNum Output string Always Hi Always Lo Hi T C Pulse Lo T C Pulse T C Toggle longint 0 to 65535 longint 0 to 65535 string Up Down string Load Only Load Hold string Once Repeat string Binary BCD string Enabled Disabled instrument ChipNum CounterNum LoadRegister instrument ChipNum CounterNum HoldRegister instrument ChipNum CounterNum Count instrument ChipNum CounterNum TCReload instrument ChipNum CounterNum Cycle instrument ChipNum CounterNum Format instrument ChipNum CounterNum SpecialGate RARER RR Page D 16 Snap Master User s Manual Triggers The following Trigger DDE commands are currently implemented only with HDI supported hardware Topic Item Exec _ Reg Poke _ Format Comments instrument TriggerMode string Standard Hardware Dependent instrument TriggerType string Free Running Analog Digital instrument TriggerChannel string Analog element letter and channel number Digital Bit and bit number instrument TriggerCondition string Analog Above Below Inside Outside Positive Slope Negative Slope Digita
22. Format string string string string string string string string string Format string string string string Page D 3 Comments full path and file name full path and file name closes filename instrument if filename omitted closes active instrument window displays the Status Log hides the Status Log Yes No On Off On Off hides workspace window shows workspace window Yes No Yes No determines if user is asked to save instrument before closing the window file path of SM EXE directory path of DEFUSER directory path of SYSDATA version string from About box of specified Snap Master DLL file Comments element letters used in instrument element names used in instrument element name for element letter Yes No Replace ElementLetter with the element letter you want the name for For example to retrieve the element name for Page D 4 D 4 A D Demo Topic Item Exec instrument SampleRate instrument Units instrument Label instrument Duration instrument NumberOfPoints instrument Continuous instrument StopAfter instrument FirstChannel instrument LastChannel instrument SelectedChannels instrument NumSelectedChannels instrument ClockType instrument MinChannel instrument MaxChannel instrument num On D 5 Display Menu And Window Commands Topic Item Exec instrument CommandBar instrument ScrollBar instrument StatusBar instr
23. Page 15 7 15 3 Thermocouple Linearization Table Columns This element is included with the Data Acquisition Module The Thermocouple Linearization element or TCLinear provides a simple method for linearizing B E J K N R S and T type thermocouples without using dedicated hardware Up to 256 channels can be linearized using this element Thermocouple Linearizer Settings Driving Channel A0 Voltage zl CIC Settings Area 1 Result Active Input Type Temperature Label Channel Channel Units 3 5KXVeMage K jelius n Eas bem il i Celsius sn LEMP ME y J Celsius Temp id y 3ceme Temp Sc J sng G lsius LEMP J Celsius i Temp snd tang CSI OR id Celsius Temp J Celsius TEMP J Celsius Temp J Celsius i Temp J 4 CELSIUS m LEMP oer P J eus emp oes J Celsius Temp IMNNWEIC CEU NERONE UNE 7T S T NR SCA Cancel Help Figure 15 8 Thermocouple Linearization Settings The Driving Channel setting for this element determines which channels with a given letter description are available for the Input Channel table selection When you select a driving channel all channels using the same element letter can be scaled using this element To linearize channels from more than one element letter such as more than one A D element you will need to use multiple TCLinear elements
24. Triangle Parameters Frequency no Hz Amplitude 10 Volts DC Offset 0 volts Phase fp Degrees Symmetry fo z Canoe deb Figure 5 12 Triangle Settings The Triangle function produces a waveform which oscillates between its minimum and maximum values with no hold time at the minimum or maximum The oscillation occurs at the specified frequency with the Symmetry the relative slopes of the rise and fall times Frequency Specifies the frequency of the waveform Amplitude Specifies the peak to peak amplitude of the waveform DC Offset Specifies the offset from 0 volts for the resulting waveform Phase Specifies the phase shift of the resulting waveform Symmetry Specifies the relative slope of the rise and fall times A value less than 5046 means the rise time of the waveform is greater than the fall time A value equal to 5096 means the rise and fall times are equal A value greater than 5096 means the fall time is greater than the rise time White Noise Settings Minimum 0 Volts Maximum 5 Volts Cancel Help Figure 5 13 White Noise Settings The White Noise function produces a random noise waveform that moves between the Minimum and Maximum values Minimum Specifies the lowest value for the waveform Maximum Specifies the highest value for the waveform Wave Generator Page 5 9 5 2 Menu Commands Edit Menu Insert Delete Append Settings Menu Frame Settings Waveform Settings Pleas
25. on the Waveform table entry for the first stage of channel A1 Ramp Settings Start At Hold Previous Value C New Starting Value 0 Volts EndAt 5 Volts Figure 5 23 Stage 2 Ramp Settings 9 Set the Start At to Hold Previous Value 10 Set the End At value to 5 volts 11 Press the OK button to close the Ramp Settings 12 Position the selection box in the third row Stage Length column and enter 2 Now let s set up the remaining stages Wave Generator Page 5 15 13 Position the selection box in the fourth row Waveform column If the Waveform is not already set to Sine select it from the pull down list 14 Press the button select the Settings menu Waveform Settings command or double click on the Waveform table entry for the first stage of channel A1 Sine Settings Sine Parameters Frequency Constant ho Hz C Linear Sweep Initial 1 Hz Clog Sweep Fina gt He Amplitude 2 Volts Rectify Damping Off Linear C Exponential Coefficient 2 DC Offset 5 volts Phase f Degrees Cancel Help Figure 5 24 Stage 3 Sine Settings The default frequency for a Sine wave is 1 Hz so we only need to change the amplitude and DC Offset By setting the DC Offset we change the zero line of the waveform to coincide with where our Ramp function left off 15 Set the Amplitude value to 2 16 Set the DC Offset to 5 17 Press the OK button to close the Sine Settings
26. 18 Position the selection box in the fourth row Stage Length column and enter 5 The sine wave is active between 3 and 8 seconds so the duration is 5 seconds Finally we need to ramp the function back down to 0 so we will use the ramp function again 19 Position the selection box in the fifth row Waveform column From the pull down list select Ramp 20 Press the button select the Settings menu Waveform Settings command or double click on the Waveform table entry for the first stage of channel A1 Ramp Settings Start At Hold Previous Value C New Starting Value Volts EndAt 0 Volts Cancel Help Figure 5 25 Stage 4 Ramp Settings 21 Set the Start At to Hold Previous Value 22 Set the End At value to O volts Page 5 16 Snap Master User s Manual 23 Press the OK button to close the Ramp Settings 24 Position the selection box in the fifth row Stage Length column and enter 1 Now let s assign a channel name and activate the channel 25 Position the selection box in the second row for Channel A1 Channel Label column and enter Stages 26 Position the selection box in the second row for Channel A1 Active column From the pull down list select Yes to activate the channel 27 Close the Wave Generator table using the File menu Close Wave Generator command 28 Save the instrument with the button or select the File menu Save Instrument command Running the E Display Page 1 BEES
27. Edit Menu Copy View Menu Command Bar Status Bar Scroll Bar Display Page Page 3 17 Print Margin Sets the respective margins in inches for the printout Save As Default The Save As Default button allows you to store the current Print Display settings as defaults These defaults are used each time a new Display element is included in an instrument and when the user presses the button from the Display window s command bar Once the Display looks the way you want you can make a bitmap copy of the Display window image and paste it into other Windows programs In fact this User s Manual was created by copying various parts of the Snap Master program and pasting it directly into a word processor These instructions give a quick example of how to use copy the Display window picture to the Clipboard then paste the contents of the Clipboard in the Paintbrush program supplied with Windows e Select the Display window s Edit menu Copy command e Run the Paintbrush program e Select the View menu Zoom Out command This allows the full picture to appear in the window e Select the Edit menu Paste command A cross hatch pattern appears that represents the size of the image on the Clipboard To reposition the picture drag it around the page e Select the Edit menu Paste command This second Paste command places the contents of the Clipboard into the cross hatch area This is a special command for Paintbrush only
28. Save the instrument with the button or with the File menu Save command Page 14 36 Snap Master User s Manual Runnin g the ee ET Gallas E EE m Instrument AD vs Time i Frame 1 10 0 Time Sec af XFRINO vs Frequency Frame 1 0 Frequency Hz 5 Frequency Hz 11 15 54 AM Figure 14 25 Results of Transfer Function and Coherence When you start the instrument the plots of channels AO and DO appear in real time The remaining plots are displayed after the window length of 200 points is reached and the functions are calculated Figure 14 25 shows a Y T plot for channel AO a Y T plot for channel DO a Mag vs F plot for channel NO and a Mag vs F plot for channel PO The plot of channel NO has the X Axis set to display from 0 to 5 and the Y Axis to display from 0 to 2000 The plot of channel NO has the Y Axis set to display from 0 9 to 1 1 In the lower right corner the plot of the Transfer function shows a signal component at 0 5 Hz which we expect to see from the sine wave in channel AO From the Coherence function plot in the lower left we see that the coherence ratio is one for the entire measured range of the frequency spectrum This means that there are no other inputs to the system except DO and AO is the output Utility Elements Page 15 1 Chapter 15 Utility Elements D5 Dc REDAY M
29. Sec z X Axis Label Time Frame Length G Duration p Sec Ci of Romts 200 a Number of Frames C Continuous C StopAfter 1 james m Figure 6 3 Frame Settings The Frame Settings dialog determines the frame characteristics of all channels in this DDE In element When Snap Master is the Application for the DDE Conversation the Frame Settings are automatically set by the data server This makes creating a link with Snap Master easy by automatically transferring all required information for the data links The values are not editable but they may still be viewed in this dialog Pacing Data Driven Waits for each new point from the Item to increment the point count in the frame this is the setting used when Snap Master is the DDE Server application Auto Generate Uses the Sample Rate and produces a new point at each specified time interval This setting is best used when a static value is used for the data link for example from a spreadsheet cell The DDE Out element allows you to transfer data from Snap Master to another Windows program via Dynamic Data Exchange DDE For example you could send data from Snap Master directly to a spreadsheet program to perform special analysis or generate custom reports In order to send data over DDE from Snap Master you must include the DDE Out element in the instrument However you do not need to include the DDE Out element if you are only sen
30. Snap Master User s Manual 3 Position the selection box in the sixth row Comments column Type My Block Average then press ENTER 4 Position the selection box in the second row Label column Using the keyboard type Block Avg Fcn then press ENTER 5 Position the selection box in the second row Units column Using the keyboard type Volts then press ENTER 6 Switch to the main Snap Master window and save the instrument using the button or the File menu Save Instrument command El Display Page 5 nx Fie Edi View Settings Start Layout Cursor Help Block Avg Fen vs Time Frame 1 Time Sec n Time Sec 0 Time Sec 11 11 97 10 15 14 AM Figure 12 34 Display of Cascaded Equation Results When you Start the instrument you should see the results shown This Display window shows Y T plots for RO PO and P1 The plots for PO and P1 are identical because they are performing the same calculation Command Command Bar Equation Table Columns Chapter 13 Command 13 1 Men Commands e M S A 13 2 Command Emquations Lease eee eee esee eene eee eene eset eene see ten asse ees esse sens esee soss sse sens sese senses ee soss sse sesss see sessesesseseseessssese 1373 13 3 Tutorial Creating A Trigger To Stop ceeeee ee eee see
31. e Windows 3 1 or higher e A computer which runs Windows in 386 Enhanced mode 386 or greater e 5 7 MB free hard disk space plus space for data files e 4MB RAM 8 MB recommended e Mouse or other pointing device e For high speed plotting a local bus graphics accelerator is recommended e For high speed data analysis a math coprocessor is recommended Page 1 6 Snap Master User s Manual 1 4 Installing Snap Master Snap Master s installation program is used for both new installations and upgrades to existing installations To install or upgrade Snap Master follow these instructions e Insert Disk 1 of the most recent Snap Master module you received for example Disk 1 of the Data Acquisition module e In Program Manager select the File menu Run command for Windows 95 users select the Start button Run command e Typea setup in the command line use the floppy disk drive letter you are installing from then press the OK button e When you reach the screen that specifies the destination path for Snap Master type the hard disk directory where you want to install the program the default is C SM If you are performing an upgrade type the directory where Snap Master is already installed e When you reach the screen that lists the installation or upgrade options select the check boxes of the Snap Master modules you are going to install or upgrade e Follow the instructions on screen and insert the correct diskettes as the
32. 13 3 Tutorial Creating A Trigger To Stop Building the Instrument The next series of tutorials illustrates how to use the Command element These tutorials use the A D Demo element the Command element and the Display element The instrument we will use for these tutorials is shown in Figure 13 3 3 A A D Demo B Command C Display Figure 13 3 Instrument for Command Element Tutorials 1 Create a new instrument with the command in the Snap Master workspace button or select the File menu New Instrument 2 Place the A D Demo Command and Display elements in the instrument 3 Activate Pipe Mode with the button or select the Element menu Pipe Mode command 4 Connect the A D Demo element to the Command element and the Command element to the Display element Page 13 10 Writing A Command Routine Snap Master User s Manual 5 Turn off Pipe Mode with the button or select the Element menu Pipe Mode command 6 Save the instrument with the button or select the File menu Save Instrument As command Save the instrument as CONDEXI This tutorial displays a message and stops the instrument when the data from channel AO goes below 0 This will illustrate how to put together a series of actions based on a given condition Command Untitled G x File Edit View Settings Help es i rey ere Soy 8 R Equation D
33. 500 Pacing Units se m C Continuous X Axis Label Time Stop After fi frames Cancel Help Figure 8 13 Frame Settings Sample Rate 100 Sec E ae lt 3 Select the Hardware pacing type If your hardware device does not support Hardware pacing use Software pacing and set the Sample Rate in the next step to 10 4 Set the Sample Rate to 100 5 Change the Frame Length to a Duration of 5 seconds The default selection for the Frame Length is the Number of Points option so we need to specify the Duration as the measuring option At this setting each frame of data will contain five seconds or 500 data points of information 6 Change the Number of Frames to Stop After 1 frame The default selection for the Number of Frames group is for the instrument to run Continuously Select the Stop After radio button The default value for the Stop After field is 1 which is the setting we want 7 Press the OK button to close the Frame Settings 8 Make sure the first channel or the channel you have your input wired to has a Yes in the Active column Data Acquisition Running the Instrument Page 8 15 9 Close the A D Settings window with the File menu Close command 10 Save the instrument with the button or select the File menu Save Instrument command 1 Press the button or the Start menu command If all is well the Display window opens and begins plotting your input signal If a sign
34. A false or lower frequency component that appears in analog data reconstructed from original data required at an insufficient sampling rate Occurs when the sampling rate is too low and therefore higher frequencies appear as lower frequencies See Nyquist Theorem Peak measurement of a varying signal A continuous signal or process The process of changing a continuously varying signal into discrete data Analog voltages are received by the system converted to digital numbers then stored or analyzed by the computer Performs near real time analysis on incoming data using algebra trigonometry integration differentiation statistics and curve fitting The results are output from this element as separate sets of data American National Standard Code for Information Exchange An ASCII file is a text file where the characters are represented in ASCII codes ASCII character codes are given in Appendix G of the IBM BASIC manual A communications protocol where information can be transmitted at an arbitrary unsynchronized point in time without synchronization to a reference timer or clock A secondary task performed by the computer in conjunction with the primary or foreground task A type of filter that allows a band of signal frequencies between two set frequencies to pass while attenuating all signal frequencies outside the bandpass range Defines the location of the input and output ports of the computer used to control computer
35. AO and Al RO AO and o Al The AND function performs a Boolean AND for the current point in argl with the current point in arg2 The frame characteristics for the function result are determined by the Options We recommend that the Oversampling option is always used for the Default Option for this function argl or arg2 Options o Oversampling u Undersampling Examples RO AO or Al RO AO or o Al The OR function performs a Boolean OR for the current point in argl with the current point in arg2 The frame characteristics for the function result are determined by the Options We recommend that the Oversampling option is always used for the Default Option for this function Analysis and Frequency Analysis Page 12 19 XOR NOT Comparison If Then Else argl xor arg2 Options o Oversampling u Undersampling Examples R0 AO xor Al RO AO xor o Al The XOR function performs a Boolean XOR for the current point in argl with the current point in arg2 The frame characteristics for the function result are determined by the Options We recommend that the Oversampling option is always used for the Default Option for this function not arg1 Example RO not AO The NOT function performs a Boolean NOT for each point in argl arg comparison arg2 Options o Oversampling u Undersampling Examples R02 A0 AI R0 A0 o Al The Comparison function compares the current point in argl with the current point in ar
36. Activate Pipe Mode with the button or select the Element menu Pipe Mode command 4 Connect the A D Demo element to the Display element For this data pipe the A D Demo is the source element and the Display is the destination element Therefore we will connect from the A D Demo to the Display Snap Master Basics Running the Instrument Page 2 19 Position the UE mouse pointer over the A D Demo element icon then click the left mouse button The mouse pointer changes to E with the arrow pointing down and to the left As you move the cursor towards the Display element a data pipe connected to the A D Demo element follows the cursor movement Position the mouse pointer over the Display element icon then click the left mouse button A data pipe appears between the elements with the data pipe arrow pointing from the A D Demo to the Display indicating the flow of data 5 Turn off Pipe Mode with the button or select the Element menu Pipe Mode command 6 Save the instrument with the button or select the File menu Save Instrument command When you save the file this time Snap Master remembers the file name you specified previously and updates the file Before we run the instrument let s make sure the Auto Layout function is set up to create a new plot for each channel 1 Double click on the Display element to open the Display window If there are four plots one for each channel from the A D Demo in the window you can
37. B Analysis C Display Figure 2 14 Directionally Correct Instrument The organization of the Toolbox also acts as a guide to the valid connections between elements In general elements that are positioned higher in the Toolbox can be connected to an element that is positioned lower in the Toolbox Here are some general rules to follow when building an instrument e Use the same element topology in Figure 2 11 when positioning the elements The Input Analysis Output topology allows data to flow in a left to right direction using the element and data pipe arrows as indicators of data in to data out It will also help to identify the different types and general functions of the elements Page 2 16 Frame Characteristics Snap Master User s Manual e Minimize the number of elements you send data through Using the minimum number of data pipes allows for the fastest transfer of data between elements In addition it simplifies the flow chart view of the instrument e Keep all data pipes in view and not hidden behind elements By keeping all data pipes in view you will reduce the risk of error and will aid in troubleshooting the instrument When you move an element all of its connected data pipes move with it Every channel in Snap Master has specific frame characteristics which consist of e Sample Rate e Number Of Points Per Frame e Duration Of Frame calculated by dividing the number of points per frame by the s
38. Binary FBDF ASCII Plotter Binary Plotter CSV Yes No Yes No speed multiple between 10 slowest and 10 fastest with 0 equaling normal speed Comments pointwise data values X axis label X axis units Frame duration in points Sample rate Current frame number Y axis label Y axis units Factor Offset Default Y axis minimum Default Y axis maximum Replace DDEOut with the element letter of the DDE Out element and replace ChNum with the element letter and channel number of the channel whose information you want For example to get the frame number of channel AO through the DDE Out element designated as element Z the item is Z A0 frameNumber A hot or warm link can be designated to these DDE Out items When the Block Mode setting is greater than 1 all values sent by the data item are separated by a Carriage Return Line Feed For more information on the DDE Out element refer to Chapter 6 DDE Commands and Parameters D 9 Sensor Topic Item FileNew FileOpen filename FileSave FileSaveAs filename FileClose Insert SensorID Delete SensorID View NumIDs RowNum SensorID SensorID Channel SensorID Label SensorID ModelNumber SensorID Kind SensorID Type SensorID Manufacturer SensorID SerialNumber SensorID Factor SensorID Offset SensorID InMin SensorID InMax SensorID InUnits SensorID OutMin SensorID OutMax SensorID OutUnits SensorID FreqMax SensorID CalDate SensorID Inter
39. Ch2 is a signal measuring displacement The result units are units for acceleration over the units for force such as Ib in Dynamic Stiffness is the inverse of Dynamic Flexibility Transmissibility is a special transfer function used in mechanical systems In order to use this function the two input channels must have the same frame characteristics The numerator Chl of the calculation is a signal measuring force and the denominator Ch2 is a signal measuring velocity The result units are units for force over the units for velocity such as Ib in sec The Transmissibility function is equivalent to Impedance and is the inverse of Mobility Transmissibility is often used in vibration isolation and other dynamic systems There are two types of transmissibility functions force and motion For a linear system these two functions are identical Dynamic Inertia is a special transfer function used in mechanical systems In order to use this function the two input channels must have the same frame characteristics The numerator Chl of the calculation is a signal measuring force and the denominator Ch2 is a signal measuring acceleration The result units are units for force over the units for velocity such as lb in sec Dynamic Inertia is the inverse of Dynamic Accelerance 14 3 Window Types Before proceeding into the inner workings of the FFT element it is important to keep in mind the differences between the analog Fourier Transfor
40. Instrume n t File Edit View Settings Start Layout Cursor Help Voltage vs Time Frame 1 Voltage vs Time Frame 1 0 Time Sec i Time Sec Stopped instrument Untitled 7 Voltage Volts Voltage Volts 11 10 57 2 16 53 PM Figure 5 26 Results of Multiple Stages Tutorial When you run the instrument the waveform appears as data comes in from the Wave Generator in real time If the waveform contains large jumps and the data does not appear as shown above make sure your Hold Previous Value and or DC Offset settings are correct Dynamic Data Exchange Page 6 1 Chapter 6 Dynamic Data Exchange 6 3 Tutorial Receiving Data In From A Local Spreadsheet cec ecce ee eee eese eese eee een esee eens ese esoseseessssecees O7 11 6 4 Tutorial Sending Data Out To A Local Spreadsheet e eeee ee eee eee eere esee eee een esee eene see eoseseessssesessesseces 6 14 6 5 Tutorial Using Block Mode ssent esee eese e eere enses assesses estesa esee enss esos ens esee sens sse io aisina sataniese sieis O7 1 7 6 6 Tutorial Sending Data To A Spreadsheet Over NetDDE eee eeee eese eere eee eee eene see eene see eeoseseessseseeseseeces O7 LO 6 7 Tutorial Sending Data To Snap Master Over NetDDE ceres esee etes eese eene
41. Modulation Frequency 50 Hz 5 Hz Amplitude 10 Volts 2 Volts DC Offset 0 Volts Phase 0 Degrees Cancel Help Figure 5 2 Amplitude Modulation Settings The Amplitude Modulation function varies the amplitude of a single frequency sinusoidal wave the Carrier as a function of the magnitude of another single frequency sinusoidal wave the Modulator In mathematical terms the waveform is the result of multiplying the Carrier by the Modulator To ensure that all of the information in the Modulator signal is retained in the modulated result the frequency of the Carrier signal should be much higher than the frequency of the Modulator signal Frequency Specifies the frequency of the Carrier sine wave and Modulator sine wave Amplitude Specifies the peak to peak amplitude of the Carrier and Modulator sine waves The overall amplitude of the resulting waveform is the equal to the multiplication of these values DC Offset Specifies the offset from 0 volts for the resulting waveform Phase Specifies the phase shift of the resulting waveform Bessel Bessel Settings Bessel Parameters Frequency Moo Hz Amplitude 10 Volts DC Offset 0 volts Phase f Degrees PH p s Cancel Help Figure 5 3 Bessel Settings The Bessel function is often used in frequency modulation to control either the amplitude or frequency of a signal Page 5 4 Constant Cosine And Sine Snap Master User s Manual Constant Setti
42. Print Setup Page 2 13 Insert a new row in the table at the current row Appends a new row after the current row Deletes the current row Prints the current table contents Clears all settings for the element and restores the default settings Imports a saved element settings file into the current instrument Exports the current element settings to a previously specified file name Exports the current element settings to a new file Prints the contents of the table to the default printer Print Table Print Method Printer Setup C Actual Size C Fit To Page Width Save As Default Include Grid Lines Iv Window Title Iv Date amp Time r Print Margin Left hoc inches Top no inches Bight fi inches Bottom 1 inches Cancel Help Figure 2 12 Print Table Setup Opens a dialog to configure the printing of this table Print Method Actual Size Uses the table font sizes to print the table at full size Fit To Page Width Reduces the table so the entire width of the table prints on one page Grid Lines When selected the grid lines from the table are printed Window Title When selected the title of the window is printed at the top of the page Date amp Time When selected the current date and time are printed in the bottom left corner of the page Print Margins Specifies the margins for the printout on each side of the page Page 2 14 Save As Default Close Edit Menu Undo R
43. Sec tt of Points 2000 estem o standard Number of Frames E 1 CIO DAS16 Continuou igi z I Status Messages C Stop After f frames Configuration F7 Stop On Eror zum Figure 8 2 Dialog Interface for A D Settings The dialog interface for hardware elements is used in older versions of Snap Master as well as older hardware drivers Most drivers are developed using HEM Data s HDI or Hardware Driver Interface HDI provides a common user interface so setting up a hardware device is the same regardless of the type or manufacturer of the hardware Older drivers that do not use HDI will continue to use the dialog interface Most of the settings in the table interface have an equivalent dialog control or button In general menu commands in the table interface correspond to either a button or a check box in the dialog interface You can not set the Factor Offset Label and Units directly in the A D element using the dialog interface you would need to use the Sensor element to do that Page 8 4 8 2 Menu Commands Snap Master User s Manual Please refer to Chapter 2 for a description of the common menu commands Edit Menu Reset To Default Resets the Factor Offset Label and Units to the default values for the selected channels Settings Menu Frame Settings Frame Settings Pacing Frame Length Type Hardware DMA zl Duration 5 Sec Location C Internal C Extern
44. Simpson s Rule t Trapezoidal a order Adams Bashforth order from 1 to 6 g order Gear s order from 1 to 6 Examples RO intg A0 RO intg a 4 A0 The Integration function calculates the area under the curve of arg with respect to the x axis For the Analysis element the area change is calculated with respect to time arg 1 dr For the Frequency Analysis element the area change is calculated with respect to frequency arg Ddf This function requires that arg1 not be a single value The available options specify the method used to perform the integration the Rectangular or Boxcar Simpson s Trapezoidal Adams Bashforth or Gear s method For the Adams Bashforth and Gear s method the order of the method between and 6 is specified as well For example a fourth order Gear s integration would look like this RO intg g 4 AO Page 12 16 Y X Integration Correlation Statistical Functions Average Running Average Snap Master User s Manual intgyx arg1 arg2 Examples RO intgyx AO A1 RO intgyx AO RO The Y X Integration function is similar to the standard Integration function except that instead of an integration with respect to time the integration is performed with respect to another channel This effectively calculates the area under the curve of arg with respect to arg2 arg 1 d arg 2 if the channels were plotted on a Y X plot This function requires that both argl and
45. Spectral Lines Main Lobe Width Spectral Lines Side Lobe Height BSSe Beebe oO Best Case 35 116 80 6 dB BSSR Eee eB OS Worst Case 44 101 8 dB The Parabolic window operates better in the worst case with a relatively narrow 60 dB bandwidth The best case response is virtually skirted with much of the main lobe energy below 60 dB Parzen Frequency Response 60 dB Bandwidth Spectral Lines Main Lobe Width Spectral Lines Side Lobe Height BSSR Eee SBS Best Case 7 41 8 dB 53 9 dB 8 8 5H5sgSbs5s5 Worst Case 6 26 2 dB 53 6 dB The Parzen window has a narrow main lobe in both cases but the side lobe height is not negligible One benefit of the Parzen window is the consistent response between the best and Worst cases FFT Poisson Frequency Response 60 dB Bandwidth Spectral Lines Main Lobe Width Spectral Lines Side Lobe Height BSSR Bees BO Best Case 62 40 52 8 dB BSSR Bees BO Page 14 23 Worst Case 30 10 30 5 dB The Poisson window has a wide bandwidth as indicated by the large number of spectral lines in the 60 dB bandwidth In addition the side lobe attenuation is smaller than with other window types As a result this window is best used on signals with a single frequency component or when the frequencies are relatively far apart Rectangular Frequency Response 60 dB Bandwidth Spectral Lines Main Lob
46. The main lobe width is narrow with a good drop off and low side lobes Bohman Best Case Worst Case Frequency Response 60 dB Bandwidth 5 19 1 dB 10 57 4 dB Spectral Lines Main Lobe Width 5 48 Spectral Lines Side Lobe Height 47 0 dB 115 0 dB The Bohman window is more useful when the frequencies do not fall directly on the spectral lines In the best case the main lobe is narrow and there is a drop from 20 dB to below 60 dB but the side lobe is only attenuated 47 dB The worst case has a wide main lobe width but the majority of the lobe is below 60 dB Cauchy Best Case Worst Case Frequency Response 60 dB Bandwidth 19 56 9 dB 113 Spectral Lines Main Lobe Width 19 10 Spectral Lines Side Lobe Height 66 2 dB 36 0 dB The Cauchy window has respectable performance in the best case assuming the width of the main lobe does not interfere with measurements for frequencies that are within nine spectral lines For the worst case the side lobe height is higher than with other windows but the overall response is approximately skirted around 75 dB Page 14 18 Cosine 4th Power Frequency Response 60 dB Bandwidth Spectral Lines Main Lobe Width Spectral Lines Side Lobe Height Snap Master User s Manual Worst Case 10 29 115 6 dB In both the best and worst cases the Cosine 4th Power window provides an accurate representation of the source data The main lobe width and drop off in the best cas
47. commands are not sent over a cold link but to the user commands have the same characteristics of a cold link Dynamic Data Exchange DDE And Other Applications 6 1 DDE In Command Bar Page 6 5 An application must support DDE in order to send and receive information Most Windows applications support DDE to some extent For example Excel acts as either a client requests data or a server sends data Word for Windows on the other hand acts as only a client which means another application cannot request data from a Word document If you are creating your own custom application it is up to the programmer to include DDE capabilities in the program For most standard applications a simple mechanism is used to create a DDE link This usually comes in the form of a Copy and Paste Link command To create a link you would select the data you want to transfer from the server application and issue a Copy Link command usually located in the Edit menu This is similar to a standard Copy command except that the DDE Link information is copied to the Clipboard Then switch to the client application and perform a Paste Link command to complete the link The DDE In element imports data in real time using Dynamic Data Exchange Data from other applications such as spreadsheets or custom programs can then be used by other Snap Master elements such as Analysis Display and D A If you are running Snap Master on a Windows For Workgroups network
48. from its normal Low to High on a T C for one count a Low Pulse where the Output changes from its normal High to Low on a T C for one count or a Toggle where the Output inverts between High and Low at each T C If the Output is not used elsewhere it can be set to a continuous High or Low state The 9513 has two configurable registers per channel to hold 16 bit data values from 0 to 65535 the Load register and the Hold register This Load register sets the initial count of the counter and a Terminal Count T C can be used to reset the value of the counter to either the Load or Hold register value For most applications the Hold register is only used to transfer the current data value from the counter to Snap Master while the counter is accumulating A Terminal Count T C event occurs when the counter value reaches 0 The T C is used to reload the counter with Load or Hold register value or to control other counters The 9513 has a number of predefined modes to describe the counter function These modes define common uses for the various input and output signals as well as the counting methods and other options While most applications are satisfied with one of the modes they do not cover all possible combinations A brief description of each mode and its use in Snap Master is included below Software Triggered Strobe with No Hardware Gating At the beginning of each frame the Load register sets the initial value of the counter On
49. hardware Page A 2 Binary Bipolar Bit Board Buffer Burst Mode Byte Channel Click Close Box Command Comment Field Common Mode Rejection Ratio CMR Concurrent Configuration Counter Timer Cursor D A D A Board Snap Master User s Manual Data file format for Snap Master that stores raw data using binary numbers A signal range that includes both positive and negative values A unit of computer information equivalent to the result of a choice between two alternatives as yes or no on or off 0 or 1 It is the smallest piece of information in the computer system I O boards are typically between 8 to 16 bits Raise 2 to the power of the number of bits of the board to define resolution which is the smallest significant number to which a measurement can be determined A data acquisition board is required to work with Snapshot Storage Scope and Snap Master Data Acquisition software The board may include both A D and D A capabilities A storage location used for holding information that is to be used at a later time A high speed data transfer in which the address of the data is sent followed by back to back data words while a physical signal is asserted This term refers to eight related bits of information Eight bits equals one byte Specifies the location of a signal going to or coming from the A D board A channel is always associated with an element letter To click with the mouse pre
50. indicated by a check mark each element you add to the instrument is automatically placed according to the Icon Spacing setting If the icon disappears resize the instrument window vertically to find it The distance between elements is controlled by the Icon Spacing parameter in the Desktop section of the Control Panel in Windows The recommended setting for the Icon Spacing is 100 Snap Master Basics Global Settings Global Settings Startup Options rs C Reopen Previous Instruments J Clean Workspace No Instruments Page 2 7 Appearance Iv Show 3D Dialogs Table Fonts Edit Bar Text Body Text r Workspace Settings T Prompt To Save Instrument On Close T Table Interface for Hardware Elements Iv Detect Task Bar Windows 95 Data Acquisition Settings Number of DMA Boards 2 oK Cancel Help Figure 2 7 Global Settings The Global Settings dialog box controls parameters used throughout Snap Master Startup Options Show Opening Animation Clean Workspace Reopen Previous Instruments Workspace Settings Prompt To Save Instrument On Close Detect Task Bar Windows 95 Appearance Show 3D Dialogs Edit Bar Text Body Text When selected the Snap Master logo is animated when you start Snap Master To speed up loading time turn this option off Opens Snap Master without any instruments in the workspace Opens the instrument files you were working on when you
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52. perform a Forward FFT with the window then perform an Inverse FFT on the result and compare it to your original waveform Finally we are to the point where we can select a window type When making the selection you must answer these questions e Ts the source signal periodic non periodic or transient For non periodic and transient signals selecting a window type which zeros out the first and last points may provide more accurate results If the signal is periodic this question is not as important as the others e Do the frequencies of interest fall on a spectral line or are they in between spectral lines If the frequencies fall directly on the spectral lines the frequencies being calculated by the FFT then the Best Case values for each window can be used to decide which window to use When the frequencies fall between spectral lines or you are not sure where they will fall the Worst Case values provide a better response e Are my frequencies of interest close together or spread out If the frequencies of interest are concentrated select a window with a smaller main lobe width and greater side lobe attenuation to reduce interference If the frequencies of interest are spread out the effect of the main lobe is less pronounced than the effect of the spectral lines FFT Window Width Response Page 14 13 Figure 14 4 lists the different windows available in Snap Master along with information concernin
53. the list Page 15 16 Specifying The Rise Time Running the Instrument Snap Master User s Manual 1 Press the Smoothing Options button Smoothing Options Result Channel BO x Rise Time 0 2 Specify As Seconds C Points C Frame Length Cancel Help Figure 15 24 Smoothing Options 2 Select channel BO from the Result Channel list We are going to set the rise time for the filter used by result channel BO For our 1 Hz square wave the default used by Wave Generator let s pick a rise time that is sufficiently long so we can view the effects of the filter 3 Set the Rise Time to 0 2 4 Set the Specify As to Seconds 5 Press the OK button to close the Smoothing Options dialog box 6 Press the OK button to close the Smoothing dialog box 7 Save the instrument with the button or select the File menu Save Instrument command E Display Page 1 icf x Eile Edi View Settings Start Layout Cursor Help Filter vs Time Voltage Volts fe Time Sec Time Sec 11 11 57 Figure 15 25 Results of Smoothing Tutorial When you run the instrument the original swept sine is channel AO and the filtered result is BO As you can see the filtered result tapers off in amplitude as the frequency of the original signal increases is more trapezoidal due to the rise time setting of the s
54. the statistical minimum for all data in the channel but is the value passed to the Display element which determines the minimum Y axis value when Auto Scale is used For A D Boards without the Sensor element the yMin value is the lower value of the channel s input range If a Sensor is applied the value is the InMin value from the Sensor Specifications table Transfers the default maximum value for the channel This is not the statistical maximum for all data in the channel but is the value passed to the Display element which determines the maximum Y axis value when Auto Scale is used For A D Boards without the Sensor element the yMax value is the upper value of the channel s input range If a Sensor is applied the value is the InMax value from the Sensor Specifications table Dynamic Data Exchange Block Mode Page 6 11 The Block Mode setting allows you to send multiple data points in a single string This is useful for transferring data into multiple cells in a spreadsheet or for sending larger blocks of data over DDE at once Each data point is separated by a Carriage Return Line Feed CRLF The Block Mode Settings only applies to the data item The default Block Size is one point which means that each data point is sent out as the DDE Out element receives it appended by a CRLF When the Block Size is greater than one the DDE Out element queues the data points until the nth point is received then it sends out the complete st
55. the two input channels must have the same frame characteristics The numerator Ch1 of the calculation is a signal measuring volume and the denominator Ch2 is a signal measuring pressure The result units are units for volume over the units for pressure such as gallons psi Dynamic Compressibility is the inverse of Bulk Modulus Bulk Modulus is a special transfer function used in hydraulic systems In order to use this function the two input channels must have the same frame characteristics The numerator Chl of the calculation is a signal measuring pressure and the denominator Ch2 is a signal measuring volume The result units are units for pressure over the units for volume such as psi gallons Bulk Modulus is the inverse of Dynamic Compressibility Admittance is a special transfer function used in electrical systems In order to use this function the two input channels must have the same frame characteristics The numerator Ch1 of the calculation is a current signal and the denominator Ch2 is a voltage signal The result units are amps volt Admittance is the inverse of Impedance Dynamic Flexibility is a special transfer function used in mechanical systems In order to use this function the two input channels must have the same frame characteristics The numerator Chl of the calculation is a signal measuring displacement and the denominator Ch2 is a signal measuring force The result units are units for displacement over the uni
56. with the active device indicated by a check mark next to the menu option Because Snap Master supports multiple hardware devices running simultaneously each piece of hardware is assigned a unique number Hardware that has multiple functions such as A D D A and Digital I O uses the same device number A menu caption of all dashes means there is no hardware specified for that device number Device Overview Device 1 CIO DAS16 Name SIC AID D A DIN DOUT CTIN CTOUT Device 1 LIO DAS TB se ES ce TES Yes m iYes z Device CIO DAS16 M Yes Yes Ves Device 3 LIDDID2d s Device 4 CIO CTROS i Device 5 Device B Device 7 Device 8 Close Help Figure 8 9 Device Overview The Device Overview dialog specifies the I O hardware for each device and shows which Snap Master elements can be used for each device Use the pull down list in the upper left corner of the dialog to change the I O hardware for each device number To disable a particular device select the horizontal bar item from the end of the list Page 8 12 Hardware Configuration Snap Master User s Manual The Snap Master hardware I O elements are abbreviated in the table as follows S C A D D A DIN DOUT CTIN CTOUT Signal Conditioning Analog to Digital Digital to Analog Digital In Digital Out Counter Timer In Counter Timer Out
57. y defuser Help Replay Options testdata dat hd S Disk In Defaults File Format Drives Snap Master Data dat x amp c hardly E File Comments Sell Fate Import Skip Lines 0 RSGM Viewer File Info Iv Include Channel Labels Line of Channels Network Jv Auto Detect Total of Points Sample Rate 1000 Sec Yos Minimum 10 Durston 2 Sec YAkisMaximum 10 wos Pomnts 2000 El Figure 4 17 Disk In Settings 2 Select the data file TEST DAT by clicking on it in the File list 3 Press the OK button in the Disk In dialog box 4 Save the instrument with the button or with the File menu Save command Disk I O Running The Instrument Page 4 15 When you start the instrument the Display window opens and displays the data stored in TEST DAT The data should look the same as it did in the previous tutorial where you saved the data to disk Notice that you can zoom in and out or use cursors and markers as if the data were just acquired 4 6 Data File Formats Data File Structure Header Information This section of the manual documents the actual file formats used by Snap Master s native file formats as well as some of the generic file formats This information will only be useful to users who plan on creating their own programs to write or read Snap Master data files such as custom file format converters or custom analysis programs Whenever data is saved in one of S
58. you may need to specify the number of points and frame duration for the t function In Snap Calc this was always referenced to the current Sample Rate and Sweep Time settings in Snapshot Equations using the following Snap Calc functions are not available using the Snap Master Analysis element Snap Calc Operator Description Snap Master Usage g Graph Use Display element h FFT Use FFT element o Output Z Coordinate conversion Merge a file into the current table This could overwrite equations already in the Analysis table so make sure to create backup copies of your equations by saving them before merging Analysis and Frequency Analysis Page 12 5 Builder Menu Analysis Equation Builder Line 7 Equation PO intg range find R 2 gt 2 93 find R2 gt 6 9 A0 Quick Functions H es Peal or v Lr o s aose block range Define r Function Builders Statistical Filters Syntax inta argumentl Description Calculates the area under the curve of argument with respect to time lt lt Previous Line Cancel Help Next Line gt gt Figure 12 3 Equation Builder The Equation Builder provides a simple method of creating and editing the contents of the Analysis equation table The Equation edit control is where the actual building of the equation is performed You can type the equation in this text box just as if you were using the standard equation table However what makes the Equation Bui
59. 10 Volts Minor Divisions Minor Divisions 2 Format Default zi id a Show As C Tick Mark Significant Digits fi 3 G None Cance Help Figure 3 34 X Axis Settings With All Values Shown 5 Double click on the X Axis region of the Y X plot located in the lower left corner of the Display window 6 Select the All Major Divisions radio button under the Show Axis Values check box The axis values are now shown at each major division 7 Press the OK button You should now see a value underneath each grid line on the X Axis As you can see there are a number of options available for customizing the Display window Experiment with each setting to determine the best way to present your data E Display Page 1 BEE File Edt View Settings Start Layout Cursor Help 2 3 4 5 J 6 7 Channel AO from A D Demo Al vs Time Ls 1 Time Sec Time Sec Figure 3 35 User Defined Title and Axis Values Page 3 36 Snap Master User s Manual 3 5 Tutorial Using Display Pages Moving a Plot ToA New Display Page Changing The Display Page Title Now that we have customized the individual plots how do we customize the Display layout even further For example how do we make the Y X plot full screen Also how do we rearrange the Y T and Strip Chart plots to appear in
60. Avg is set to 4 The FFT element result will output four frames of data or one for each window width within the frame number of windows window width number of points per frame The first frequency frame has the FFT of the first 250 points the second frequency frame is the average of the FFT of the second 250 points with the first frequency frame the third frequency frame is the average of the third 250 points with the second frequency frame etc FFT Settings Noise Floor Page 14 5 If the waveforms you are analyzing are not periodic within the window phase differences can cause averaging to decrease This is because the Forward FFT has both a real and imaginary part from complex algebra and the magnitude of the data depends on both parts Therefore Averaging should be set to No when the window width does not exactly equal the period of the analyzed waveform Window averaging is available only for the Forward FFT function For all other functions the Avg column is disabled but the Yes or No in the column reflects the operation of the function If averaging is used in the calculation of the function then the Avg column setting is Yes and if no averaging is used the setting is No Partial Frame Specifies how to handle incomplete data frames for the FFT calculation Zero Extend appends a value of zero for the remaining points in the window width then performs the frequency domain calculation Zero extending the data could
61. Chapter 15 Utility Elements ITA A L E A EE E T E Auto Toggle Settings ivi pedum SE ee a i a eas 15 2 15 2 Tutorials Relay sics ccsscsssscoosseosssessssssonssesscenstosedensesonsdssdeensansdensessddensepocoonsassscensdeosdevsasescesassesoesasssccsesses ES Building the Instrument ssc s s 2 3 02 12m Deren de eas er ERE Pere eee IRR De E DEO ERE des 15 4 Gontiguring The Wave Gereratot ii 5 noioh ote te n dede E p terre Rain 15 4 Setting Up The Relay eei ERU eU terit beet ni eibi rre ub cobs e bul ER des 15 5 Specifying The Auto Toggle Settings aiin na R T E A a R aE iS 15 5 Running th Instr ment 2 m saves ao ea aa ae ect aeee a Saag aa S AAi aaa eE Oe RR de rake 15 6 15 3 Thermocouple Linearization eeesssesessoeeessocsessoessssocssssessssoesessoessssoesssoesessoseessoessssossssoesssssesesssessss 157 7 Table Colitis aa a a a ek denm Se a a a ee Siete oat at 15 7 CJG Seton TEE 15 8 15 4 Tutorial Thermocouple Linear ization scsccsscssscsseccsscsecsssccccessscscesssscscesssscsesssscssesssscseees 15 8 Building the DInstr ment 4 oninia aepo tapete preterea 15 8 Configuring The Wave Generato enorer reino onko na eren neret net enne tenet E there tenes aa enne enne 15 9 Linearizing Thermocouple Channels sees aa ennemi enne 15 10 Specifying The CIC Settings iere p eee Ce lanes ATTE IRAE ESEAS CEEA SEAS e P Deo eve Ds 15 11 Ruu nis tlie Instrum ent 5 1 3 05 n sian DRE OO REP Ped
62. DDE In element to the Display element 5 Turn off Pipe Mode with the button or select the Element menu Pipe Mode command 6 Save the instrument with the button or select the File menu Save Instrument As command Save the instrument as DDEIN Page 6 12 Configuring the DDE Conversation Setting The DDE In Frame Settings Snap Master User s Manual 1 Open the DDE In Assignments by double clicking on the element 2 Set the DDE Conversation settings with the button or select the Settings menu DDE Conversation command DDE Client Conversation Data Source J C Local Machine C Network DDE Computer Name V Browse r Server Application C Snap Master Instrument zl I Start Server Instrument Gn Ghent Start I Stop Server Instrument On Client Stop Other Application EXCEL IV Use List To Specify Topics Cancel Help Figure 6 6 DDE In Conversation Settings 3 If the Data Source group appears in the dialog select Local Machine 4 Select Other Application for the Server Application then enter EXCEL in the adjacent text box 5 Make sure the Use List To Specify Topics check box is selected 6 Press the OK button to close the DDE Conversation settings 1 Set the DDE Frame Settings with the button or select the Settings menu Frame Settings command Frame Settings Pacing T Type C Data Driven Auto Generate Sample Rate 10 7 Sec Pacing Units Sec X X
63. DialMeterEndAngle instrument Plot Ch DialMeterStartValue instrument Plot Ch DialMeterEnd Value instrument Plot Ch DialMeterDivisions instrument Plot Ch DialMeterNeedle Width Plot Settings Histogram Plots Topic Item Exec instrument Plot Ch HistogramAppearance instrument Plot Ch HistogramFilled instrument Plot Ch HistogramBarWidth Req AQUA HRS KON Poke ARO RS Format single single string string string string string string single single single single integer integer Format string string single Page D 9 Comments RGB values separated by commas Dial Meter set Needle color RGB values separated by commas Dial Meter set Dial color Decimal Scientific Engineering fill out edit controls as passed Vertical Horizontal any pre defined style from the Style combo except User Defined value between 0 and 360 value between 0 and 360 set the min value set the max value Comments Lines Bars Yes No percentage Cursors And Markers Topic Item Exec instrument Plot NewCursor instrument Plot NewMarker instrument Cursor VeriticalCrossHair instrument Cursor HorizontalCrossHair instrument Cursor SkipRate instrument Marker Label instrument Marker Background instrument Marker FontName instrument Marker FontStyle instrument Marker FontSize instrument Marker HorizontalPosition instrument Marker Ver
64. ET CE NUN 0 to p 1 p to Qp 1 2p to Bp 1 3p to 4p 1 The best way to illustrate the Block function is to provide some examples In the above figure the total frame length for arg1 is n points and the block size for the calculation is p Assume that our equation is RO block 10 AO and the frame length is 40 points numbered from point 0 to point 39 The data from channel AO is decimated into result channel RO which contains 4 points the block size divided into the frame length and the values of RO are as follows At point RO equals 1 point 9 of channel AO 2 point 19 of channel AO 3 point 29 of channel AO 4 point 39 of channel AO For another example assume that our equation is Rl block 10 avg AO and the frame length is 40 points which effectively decimates and smoothes the data in channel AO Remember that at the beginning of each block the contents are the argument are reset so the values of RO are as follows At point RO equals 1 the average of points 0 9 of channel AO 2 the average of points 10 19 of channel AO 3 the average of points 20 29 of channel AO 4 the average of points 30 39 of channel AO Now let s add an overlap of g points to the block function The function is still output at each interval of p points but each calculation after the first looks at the previous g points The start of the interval occurs at each k p q points where k is the point number of the block result and the block en
65. General Inverse FFT Hydraulic Auto Power Spectrum Electrical Auto Power Spectral Density Mechanical Cross Power Spectrum hd Ch 1 Channel A0 Voltage zi Volts Ch 2 not used aA r Scaling Window Result Frame Settings Window Width 300 points Start At Point o Overlap 9 points Spectral Resolution 0 3333 Hz T Include DC Component Type Parabolic A paren I Average Spectra Across 0 frames Rectangular Z Riemann X Partial Frame C Zero Extend Ignore Description Specifies the result channel for the calculation Rap encie line Cancel Help Next Line gt gt Figure 14 2 FFT Equation Builder The FFT Equation Builder provides a convenient way to create and edit the contents of the FFT equation table All of the available functions channels and window types are listed right in the builder All rules that apply to the corresponding table entry also apply to the Equation Builder Frequency Domain Calculation Result Channel Category Function Chl Ch2 Scaling Window Window Width Spectral Resolution Type Specifies the channel number of the result This field is required Select a specific category for the Function list from a variety of engineering disciplines Select a frequency domain function for the result channel The individual functions are discussed later in this chapter Depending on the selected Function determines the numerator and denominator for the calculation Spec
66. Gets 6 15 Running the Instrumert 21er dem et pet ed ee fe teet efe eee tee pe dettes 6 16 Table of Contents Page v 6 5 Tutorial Using Block Mod e ssccsssssssssssssccsscscccssscccsssscscesssccscesssccscessscsssssssscssssccsssssscsseesseees 6 17 Modifying the Instrument sssini openers tet neret ete ee ede pta ed tee p eee eee rada edat Copymg a DDE Data Block airen iie eed e Peer esed el Running the Instrument ee oc e ee estere ge ite teet e a De Mera ea PE qe Re CHEER 6 6 Tutorial Sending Data To A Spreadsheet Over NetDDE Setting Up The NetD DE Servei oerte ete pte peet eer prt ener Prbeet petet erp restet Pet e p ertet e ERE ERN En Setting Up The NetDDE Client eec pte te ee tec eere e eos e eio Toe epo erae Edo reed Running the Instrument MEM 6 7 Tutorial Sending Data To Snap Master Over NetDDE ce eeeeeeee eene eene eese esee eeeseeeesess e 6 21 Building the DDE Client Instrument eeseeesseeeeeeeeee eee nne nen nennen nnne nnne nen eter en tenerent 6 21 Configuring the DDE Conversation ener enne nennen nne enre nnns enne enne en nen eterne 6 21 Setting Up The DDE In Charnels 5e tit eode e ete e et de eee e EDEN PTEA 6 22 Running the Instrument diete p ge den dea a eee a det rends 6 22 Data Acquisition Chapter 7 Sensors amp Signal Conditioning 7 1 Sensor Database 77 Sensor Databas
67. Hair 3 25 Cursor Data 3 19 3 25 3 26 Location 3 19 Cursor Data Hide 3 22 Cursor Data Location 3 22 Cursor Data Settings 3 22 Cursors 3 2 3 3 3 25 3 38 6 4 Cursors Linked 3 22 3 25 Cursors Secondary 3 26 Cursors Unplotted Channels 3 26 Cursosr Linked 3 19 D D A Device 11 1 11 4 Data Pipes 2 4 DDE 6 1 6 11 6 14 Client 6 2 6 3 6 5 Item 6 2 6 6 Link 12 23 Links 6 3 12 26 Server 6 2 6 3 6 5 Service Name 6 2 Text Annotations 3 27 Topic 6 2 6 6 DDE In 2 11 6 5 DDE Out 2 12 6 4 6 8 Decision Rate 13 3 Default Location 3 10 Default Settings Display 2 19 DEFUSER subdirectory 4 13 Device 2 21 8 17 11 2 Dial Meter 3 14 Differentiation 12 15 Digital In 2 11 8 13 8 17 8 21 Digital Meter 3 10 Digital Out 11 3 11 7 Digital to Analog 11 1 Disk In 3 22 4 4 Disk Out 4 8 Save Options 4 9 Display 3 1 6 4 Display Colors 3 32 Display Defaults 3 20 Display Layout 3 23 Display Pages 3 2 3 24 3 36 Snap Master User s Manual Division 12 12 DMA 1 7 2 8 Dynamic Accelerance 14 11 Dynamic Compressibility 14 10 Dynamic Data Exchange see DDE Dynamic Flexibility 14 10 Dynamic Inertia 14 11 Dynamic Stiffness 14 11 E Element Letters 2 3 Data Files 4 3 4 15 4 16 Data Files 4 4 Element List 2 6 Elements 2 10 EMM386 1 6 Engineering Units 7 1 7 4 Enhanced Mode 1 7 8 11 Equation Builder 12 5 12 7 12 29 12 32 12 34 12 37 12 40
68. Location The Default Location check box automatically places the Channel to the left of the value and the Units to the right of the value When the Default Location check box is turned off you can move and size each object by clicking and dragging the object within its plot region Once you have positioned the objects where you want them you can disable further movement by turning on the Locked check box NOTE If the Default Location check box is turned off and you add more channels to the Digital Meter plot from the Display Layout table the new channels may not appear until you turn the Default Location check box back on Rows Specifies the number of rows used in the digital meter for multiple channels When Manual is selected enter the number of rows desired Columns Specifies the number of columns used in the digital meter for multiple channels When Manual is selected enter the number of columns desired Channel Specifies if the channels are shown by Label if assigned using the Sensor or Analysis element or the channel Number consisting of the element letter and channel number Display Channel Settings Page 3 11 Data Specifies if the data is Scaled with any Factor and Offset applied to the data or Unscaled Visible Specifies if the Channel and or Units portions of the digital meter are displayed The data value is always shown Fonts And Colors Fonts and Colors operate the same for Digital Meters as for Y T
69. Master this time you will see the contents of all cells in the column update simultaneously When the next block is transferred the old values are overwritten with the new data If you change the Block Size you will have to perform the Copy Paste Link again to set up the correct number of cells in Excel If you specify fewer cells than your Block Size then Excel truncates the last points because it has nowhere to put the data If you specify more cells than the Block Size an N A appears in the extra cells because there is no data for those cells 6 6 Tutorial Sending Data To A Spreadsheet Over NetDDE Setting Up The NetDDE Server Note This tutorial requires two computers running Windows For Workgroups with sharing enabled on both computers Only one machine needs to be running Snap Master with the other machine running Excel or another DDE aware application With the inclusion of Network DDE or NetDDE in Windows for Workgroups it is now possible to send data in real time between two computers NetDDE is essentially the same as DDE on a local machine except that you can now send data between applications running on separate machines In this tutorial we will use the same instrument created in the previous section The only difference is in our interaction with the Windows Clipbook In the NetDDE scheme the machine that is sending the data in this case the one running Snap Master is called the Server The Server pro
70. Setup dialog box double click on its hot spot There are two types of cursor Absolute and Relative An Absolute cursor indicated by an Abs Type in the Cursor Data window displays the current X axis and Y axis values at the cursor position in the Cursor Data window A Relative cursor indicated by an Rel Type in the Cursor Data window displays the X and Y axis differences and the slope between two data points In Relative cursor mode the original cursor has anchors at the top and bottom of the vertical bar When you click and drag the cursor hot spot a new cursor appears with a line connecting the two cursors To change the appearance of the Cursor you can specify the Cross Hair type The Full Vertical option draws a line across the entire vertical Y axis plane at the cursor location and the Full Horizontal option draws a line across the entire horizontal X axis plane When both options are turned off a short line is drawn at the cursor location Page 3 26 New Marker Snap Master User s Manual The Skip Rate setting determines how many points are skipped when using the left and right mouse buttons to scroll through the data The Cursor Color dialog box opens the Windows standard Color dialog and allows you to set the color of the cursor To delete a specific cursor use the Delete Cursor button on the Cursor Setup dialog box The Channels group defines the Main channel which is the channel where the cursor resides Selectin
71. Spectral Density Coherence Coherent Output Power Transfer Function Hydraulic Function Compliance Impedance Dynamic Compressibility Bulk Modulus Electrical Function Admittance Impedance Mechanical Function Compliance Dynamic Flexibility Mobility Dynamic Accelerance Dynamic Stiffness Impedance Transmissibility Dynamic Inertia Numerator Ch 1 Channel Channel Channel Channel Channel 1 Channel 1 Output Output Output Numerator Chi Flow Pressure Volume Pressure Numerator Chi Current Voltage Numerator Ch1 Displacement Displacement Velocity Acceleration Force Force Force Force Denominator Ch 2 Channel 2 Channel 2 Input Input Input Denominator Ch2 Pressure Flow Pressure Volume Denominator Ch2 Voltage Current Denominator Ch2 Force Force Force Force Displacement Velocity Velocity Acceleration Example Units gpm psi psi gpm gallon psi psi gallon Example Units amp volt volt amp Example Units in Ib in Ib in sec Ib in sec Ib Ib in Ib in sec Ib in sec Ib in sec FFT Forward FFT Inverse FFT Auto Power Spectrum Auto Power Spectral Density Page 14 7 A Forward FFT converts time domain data to the frequency domain to determine the Fourier sinusoidal components of the signal Conceptually the FFT passes the signal through many band pass filters one for each frequency and examines the magni
72. Start Server Instrument On Client Start Stop Server Instrument On Client Stop C Dther Application Iv Use List To Specify Topics Cancel Help Figure 6 19 DDE In Conversation Settings 3 Select Network DDE as the Data Source 4 Enter the name of the computer where the DDE data server the instrument with DDE Out is running If you do not remember the computer name press the Browse button to find it 5 Select Snap Master as the Application 6 Select the instrument DDEBLOCK from the Instrument drop down list 7 Press the OK button to close the DDE Conversation settings Now that the link to Snap Master has been established we can set up the client to receive the data Instead of using the Clipbook as we did for Excel in the previous example Snap Master has already defined what is available to the DDE In element so we can select items directly from the Assignments table 1 Position the selection box in the first row Link Item column 2 Using the drop down list in the upper left corner of the table select channel AO from the list Snap Master automatically selects the data portion of channel AO and defines the remaining items in the table Notice that the Label and Units columns are not editable this is because these settings are transferred directly from the data server In addition if you open the Frame Settings using the button the settings are all grayed out because these are also set from the data serve
73. The Amplitude Correction factor is automatically applied by Snap Master to the FFT data In addition the standard FFT algorithm produces a result where half of the energy is in the positive frequency range and half in the negative frequency range Because most users expect that 1 volt in the time domain should correspond to 1 volt in the frequency domain the FFT element automatically adjusts the output so the results are more easily understandable to the general user The maximum amplitude resolution of the FFT depends on the source of your data For data acquired with the Data Acquisition Module the resolution is determined by the number of bits used in the Analog to Digital conversion If you are using the Wave Generator element or the General Analysis Time function then the resolution is fixed by the 24 bit floating point number The FFT element calculates its values based on a 24 bit floating point number As a result the computer s processing accuracy for the FFT will only minimally affect the dynamic range The following table lists the resolution and corresponding dynamic range in decibels which is equal to 20 log number of values Bits Number of Values Dynamic Range Resolution Bits 20 log Values 1 4 Values 8 256 48 2 dB 0 39196 12 4 096 72 2 dB 0 024 14 16 384 84 2 dB 0 006 16 65 536 96 3 dB 0 0015 24 16 777 216 144 5 dB 0 0000060 Note All data and plots for the FFT windows were obtained directly from Snap Master s
74. The Initialization No Response command is sent once at the start of a frame but it does not wait for a response from the device Use this type for devices which do not respond after commands A Start command informs the equipment to begin collecting data This command also requires a response from the RS 232 device which must contain a terminator The Start No Response command is sent at the start of a frame but it does not wait for a response from the device The Stop command informs the equipment to stop data collection The Query command is used by Snap Master to receive the next set of data The format of the incoming data and frequency of the Query command are specified by the settings in the Instrument Response group Only one Query command string is allowed per string table At the beginning of a frame the string types are sent in the following order Initialization No Response Initialization Start No Response Start Query If the string table contains more than one string definition for a specific command then Snap Master sends each active string in the order found in the table moving from top to bottom Specifies whether or not the command string is sent out by Snap Master YES or if the string is not used NO RS 232 Page 10 5 String Contains the ASCII character sequence sent by Snap Master over the serial port to the external equipment for each corresponding command Type Please refer to the man
75. This label accompanies the Output Channel number for use in the Display element and in data files If Snap Master is the data server application the label from the source instrument is used and this column is not editable Specifies the units of the Channel The default units are Volts If Snap Master is the data server application the label from the source instrument is used and this column is not editable Please refer to Chapter 2 for a description of the common menu commands Dynamic Data Exchange Settings Menu DDE Conversation Page 6 7 DDE Client Conversation Data Source j C Local Machine C Network DDE Computer Name M Browse r Server Application Snap Master Instrument Untitled 8 zj Start Server Instrument On Client Start Stop Server Instrument On Client Stop C Other Application Iv Use List Tio Specify Topics Cancel Help Figure 6 2 DDE Conversation Settings The DDE Conversation defines the source of the data for the DDE In element Each DDE In converses with multiple topics and items within an application If Windows for Workgroups is installed and networking is enabled then Network DDE or NetDDE capabilities are directly supported Data Source The Data Source group only appears when Microsoft Networking is installed and enabled If this group does not appear the setting is assumed to be Local Machine Local Machine The data server application is
76. To get a list of all IDs in the Sensor database use NumIDs to read the number of IDs then RowNum SensorID to read each ID To get a complete calibration history of a particular sensor use SensorID NumHistory to read the number of history entries then SensorID CalHistory RowNum to read the date and SensorID ScalingInfo RowNum to read the scaling data for each calibration entry Page D 14 D 10 A D Device Digital In Counter Timer In Topic Item instrument SampleRate instrument Units instrument Label instrument Duration instrument NumberOfPoints instrument Continuous instrument StopAfter instrument FirstChannel instrument LastChannel instrument SelectedChannels instrument NumSelectedChannels instrument ClockType instrument MinChannel instrument MaxChannel instrument HardwareType instrument OpenConfig instrument DeviceNum instrument ProgRangeType instrument JumperRangeType instrument ChNum ListProgRanges instrument ChNum ListJumperRanges instrument ChNum ProgRange instrument ChNum On instrument ChNum Factor instrument ChNum Offset instrument ChNum Y Label instrument ChNum Y Units Exec R c ACORN EUN e Y Y Y Y Y Y Y Y Y Y Y e x K ASSSSS Format single string string single long int string long int integer integer string integer string integer integer string none integer string string string string string single single s
77. Transfer Function and Coherence Calculating The 1 Open the FFT element by double clicking on the icon in the instrument window Transfer Function f 2 Position the selection box in the fourth row 3 Open the Equation Builder by pressing the button or select the Builder menu command FFT Equation Builder Line 4 r Frequency Domain Calculation Result Channel NO Volts Volts Category Function RIELS CADUA General Compliance Hydraulic Hydraulic Impedance Hydraulic Electrical Dynamic Compressibility Mechanical Bulk Modulus Ch 1 Output DO Volts Ch 2 Input ao zl Volts r Scaling Window Result Frame Settings Window Width 200 points Start At Point Overlap points Spectral Resolution 0 2500 Hz I Include DC Component Type Parabolic Farzon I Average Spectra Across 0 frames Rectangular Riemann X Partial Frame C Zero Extend Ignore Description Specifies the number of points analyzed by the function and the result is output after each width The Spectral Resolution is equal to the sample rate divided by the width lt lt Previous Line Cancel Help Next Line gt gt Figure 14 23 FFT Equation Builder Settings for Transfer Function 4 In the Result Channel text box type NO 5 Select Transfer Function from the Function list 6 Select channel DO from the Ch 1 list FFT Calculating The Coherence Function 7 Select channel AO from the Ch 2
78. Wave Generator in real time If a plot for AO does not appear insert a new plot using the Display Layout table If the plot does appear but the data looks fragmented make sure you are plotting All points in the Plotting Techniques section of the Plot Settings Wave Generator Page 5 13 5 4 Tutorial Using Multiple Stages Now that we have created a simple waveform using the Wave Generator element let s see how to create a more complex waveform using the stages feature For this tutorial we will use the same instrument created in the previous section The waveform we are after looks like this 1 Hz 2V p p Time Breaking the waveform down into pieces it can be described as follows Time Description 0 to 1 sec 0 Volt constant 1 to 3 sec Ramp to 5 Volts 3 to 8 sec 1 Hz 2 Volt peak to peak Sine wave 8 to 10 sec Ramp down to 0 Volts Creating 1 Open the Wave Generator table by double clicking on the element Waveform Stages uj Wave Generator Untitled File Edit View Settings Help ol x Be Coe Ramp Stage Stage Channel Channel Output Active Waveform Channel Length Units Label Units FYES at SINS nnn ml 0000 SEC Ce dud med 05 Figure 5 21 Wave Generator Settings For Multiple Stage Tutorial We will set up the new waveform in channel A1 Using the table we created for the desired waveform we s
79. a minimum each statement must contain at least the IF THEN and END IF key words the ELSE keyword is optional The complete statement can be written either as one line or spread out over multiple lines in the equation table For example the following two statements are equivalent If AO gt 6 Then BO 1 End If If AO gt 6 Then B0 21 End If If the logical value of Comparison is True then the True Action List is processed If the logical value of Comparison is False and the ELSE key word is included then the False Action List is processed When the time comes for the Command element to make a decision which is determined by the Decision Rate set in the Command Settings dialog box the equation table is read sequentially from top to bottom Therefore the order that you list the conditions directly affects the results of the decisions Page 13 4 Subroutines Result Channels and State Variables Snap Master User s Manual You can group Command statements and actions into a named subroutine at the beginning of the equation table Subroutines are executed only when they are called by name from the main text or from another subroutine The format for a subroutine is Sub SubRoutineName statements End Sub Subroutines start with the key word Sub and the single word name of the subroutine The subroutine name is immediately followed by the condition and or action list and ends with the words End Sub If you are u
80. an A D Board etc When you print the contents of the Display window this information is included in the printout Also the Show Element and Show Parameter check boxes determine if the actual DDE Request information is included in the text annotation When another application is used for the DDE Request you will need to fill in the Application Topic and Item edit controls with the DDE information you are requesting Consult the manual for that application for details on requesting DDE data Page 3 28 Clear All Cursors Clear All Markers Clear All Text Exit Cursors Snap Master User s Manual Clear all cursors in the Display Clear all markers in the Display Clear all text annotations in the Display Clear all cursors markers and text 3 4 Tutorial Changing the Display Settings Changing Line Colors and Styles Because there are so many different options and combinations for the Display element the best way to learn how to customize the Display is by using it These tutorials cover the basics of using and customizing the Display window to help get you started While you are exploring remember that you can always try to double click on an object a plot cursor marker etc to change its settings Changing the arrangement of the Display window or the plot types is always done using the Layout menu These tutorials build on the instrument you created in the previous chapter Using the four input channels of the A D Dem
81. an existing sensor in the ID column The information from the original sensor is copied as a new entry in the database with the new sensor ID The Specifications table is resorted and the new entry appears in its proper alphabetical order according to Sensor ID Page 7 6 Snap Master User s Manual Editing A Sensor Edit Sensor Sensor ID 284 532 r Description r Scaling Kind Flow z Factor 421 Type Turbine zl Offset 3 03577e 17 Serial tt B307125 Input Minimum azaz Model ti 284 532 Maximum m4 Manufacturer MAX Engineering Units gpm zl Max Input Frequency 1000 DU Ji r tput 4 joe Minimum 1 1396 Interval 1 days MS 7 54986 Last Cal Date 11 7 10 7 97 mm dd yy Units Volts OK Cancel Help Figure 7 6 Edit Sensor Dialog Box To edit one or more sensors select the sensors in the table and press the Edit Sensor button E This dialog works in the same fashion as the Insert Sensor dialog except that if you change the Sensor ID a new sensor is created in the database Alternatively you can edit the entries directly in the Sensor Specifications table except for the columns specified for Automatic Calculation The changes are written to the database when you move the selection box out of the row of the sensor you are editing or when you close the Sensor Specifications dialog box Calibration History
82. and Y axis set to None for clarity Frame 1 1 A0 Logic 0 0 Time Sec 5 Figure 8 25 Acquiring Digital Data Counter Timer Page 9 1 Chapter 9 Counter Timer 9 1 Counter Timer Input 4 eese eese eese sees seen netten tense s n EE sess sess seen sse sns se snss E ss ssis 072 9 2 Tutorial Measuring Pulse Counts 9 3 Tutorial Frequency Measurements eeeeee eee eese eee eene seen essen esee tns esee en sesso senses ee soss sse sessseessose see eesseseessseece s D LO LE Overview Of TNE 9519 e E P CTH IN Special Wiring Instructions The Counter Timer element performs various counting and timing functions using digital input signals Snap Master addresses hardware that uses a 9513 chip The Counter Timer is useful for measuring a number of events measuring the frequency of an input signal measuring the period of a signal as well as a variety of other uses When using the Counter Timer element you will spend most of your time in the 9513 Configuration dialog This is where each channel of the 9513 is configured for different functionality This dialog is accessed through the Configuration dialog because most changes in a channel s function require rewiring the inputs to the Counter Timer hardware In order to read data from Counter Timer hardware in Snap Master the hardware needs a dedicated pacing clock going in to the In
83. and configure IndustrialSQL Server and the SQL Server ODBC driver Please refer to the documentation provided with IndustrialSQL Server for more information on installation NOTE This Snap Master element can only be used on the Windows 95 or Windows NT platforms This element only operates on Historical data live data can not be imported using this element Use the DDE In element to access live data from other FactorySuite applications 16 1 Connecting to the Server You must connect to an IndustrialSQL Server database before data can be retrieved The first time you attempt to open the IndustrialSQL In element in an instrument or run the instrument you are asked to connect to an IndustrialSQL Server database This connection is maintained until you exit Snap Master Connect to IndustrialSQL Server E Server InSQL Database Runtime Connect Usemame fuser o 2 Heb o asswori xd Figure 16 1 IndustrialSQL In Login Server Name of the IndustrialSQL Server to which you want to connect Database Name of the database to which you want to connect This option may appear dimmed Username User name for your logon account Password Password for the logon account NOTE A user account is comprised of the Login ID and password A user account must be associated with the right to retrieve data or else the log on will fail For more information on user accounts contact your system administrator Page 16 2 S
84. are processed by the computer The resolution of the frequency domain or the spectral line interval is calculated as follows SampleRate SpectralLines Window Width The highest spectral line computed by the FFT element is set to one half the sampling frequency of the time domain data to prevent aliasing of the data This is also because the FFT algorithm produces an equal number of real and imaginary values using complex math Selecting a window width to create the most spectral lines is not always the best solution to providing the most accurate results While some window types force the data to zero on the ends to simulate periodicity which inherently loses some of the original data some do not and the choice of window length has an impact on the results Remember from the discussion about the FFT in the Window Types section that the FFT algorithm assumes that the incoming signal is periodic even if it is not When selecting a width it is important to match the first and last points in the window as closely as possible to increase the accuracy at the end points of the window If the first and last points are not equal then smearing similar to the effect shown in Figure 14 7 in the frequency domain will occur Values Window Boundaries First Pt 50 Hz 0 000 Last Pt 50 Hz 0 000 s FirstPt 60Hz 0 000 Last Pt 60 Hz 0 125 50 70 60 Frequency Hz Figure 14 8 Effect Of Window Width On FFT
85. are used to sample a number of analog channels at the same instant One sample hold per analog channel is required The Signal Conditioner element integrates a database of external signal conditioners such as an amplifiers anti aliasing filters etc Allows control of software programmable units Setup where all input signals share a common ground connection This requires only one amplifier per input Differential inputs are more desirable because they have better noise reduction due to common mode rejection Size Boxes allow you to minimize and maximize the window s size You can also use the mouse to click on a window s size border to make it larger or smaller Variable used in the Command element to keep track of data not available in data channels Place where Snap Master sends operating and error messages along with a time stamp Most operating messages are sent to the queue only when the Status Messages checkbox is activated In general you should keep this option turned off Error messages will always be sent to the Status Log and are indicated by a gt before the log time To find out what error was recorded highlight the log time and read the message on the right A D conversions from a data acquisition board are continuously stored streaming to disk at maximum transfer rates of computer A named list of conditions and actions in the Command element equation table Counter Timer event which occurs when the counter valu
86. arg2 are not single values corr argl arg2 Options o Oversampling u Undersampling Examples RO corr AO A1 RO corr o AO A1 The Correlation function indicates whether arg and arg2 are closely related This function requires that arg not be a single value The function result has a frame length that is twice as long as the frame length set by the Options We recommend that the Oversampling option is always used for the Default Option for this function When arg and arg are different channels the result is called a cross correlation Note that cross correlation is not commutative that is corr arg1 arg2 corr arg2 arg1 When arg1 and arg2 are the same channel the result is an auto correlation Correlation values are at their maximum when the second set of data is lagged to most closely match the first set of data which makes correlation useful in determining the arrival times of signals in noise If the shape of the signal is known it can be entered as the second set of data The lag of the maximum correlation value is most likely the location of the signal in noise Correlation is often used as an alternative to spectral analysis avg argl Example SO avg AO The Average function calculates the arithmetic mean of all points in argl The output of the function is a single point which is produced after all points in argl are processed When used with the Block function one point is produced for each block of da
87. as Points Seconds or X axis units or Frame Length By specifying a Pre Trigger length of the entire frame or 100 it is possible to set up a Trigger To Stop condition With this setting the data will not be available until after the frame is acquired and the trigger condition is satisfied Utility Elements Trigger Condition Page 15 3 Condition Specifies the signal characteristic which generates a positive trigger Condition Levels Above Below Inside Outside Positive Slope Negative Slope 1 Description Trigger occurs when the channel data is above Level One Trigger occurs when the channel data is below Level One Trigger occurs when the channel data is between Level One and Level Two Trigger occurs when the channel data is outside both Level One and Level Two When Level One is selected the Trigger occurs when the previous channel data point is below Level One and the current channel data point is above Level One When Level Two is selected the Trigger occurs when the previous channel data point is below Level One and the current data point is above Level Two When Level One is selected the Trigger occurs when the previous channel data point is above Level One and the current channel data point is below Level One When Level Two is selected the Trigger occurs when the previous channel data point is above Level One and the current data point is below Level Two Level 1 Specif
88. at low speeds or when the data must be exported to an external program The most efficient method of storing data is by writing the file in one of Snap Master s binary formats The binary files have a faster read and write time but they may not be able to be read by external programs In general binary files are used for large data files or for higher acquisition rates Page 4 2 Native Data Files Generic Data Files Snap Master User s Manual Format Data Frame Display While Speed Frequency Type Based Storing Data Standard Binary Yes Yes Med Yes Fast Binary DAT Binary Yes No High No FBDF In Snap Master there are two native binary data file formats Standard Binary and Fast Binary Standard Binary files are sufficient for applications where the aggregate sampling rate is less than 10 KHz or when performing post process analysis on previously acquired data To find the aggregate sampling rate multiply the number of channels by the sampling rate per channel for each input element If you have more than one source of data then add these values together The main advantage of this format is the data is converted to floating point numbers using engineering units if defined by the Sensor for use by all of the Snap Master elements including the Display which allows you to view the data while saving it to disk The Fast Binary data format is optimized for high speed data acquisition The main difference between it and
89. at point 600 000 When you perform a retrace the last 600 000 points are available which would be from point 400 001 to point 1 000 000 Custom Stores a user defined number of data points per channel The same caveats for memory and retrace described for the Complete Frame and Pre Trigger options apply The absolute maximum number of points allowed is 8 million divided by the number of channels Of course the amount of available memory determines how many data points can be retained This is determined by the amount of memory installed in the computer and the amount of memory remaining after loading other applications If an error occurs in the Status Log that not enough memory could be allocated you will need to lower the amount of data retained in memory To maximize the performance of the Memory function in Snap Master close any other applications to increase the available memory As a rule of thumb do not allocate more than 1 4 your installed physical RAM for A D memory without testing to make sure the instrument operates without A D Overruns Use the actual amount of installed memory NOT the amount of available memory reported by Windows which may include virtual memory For example if your computer has 4 MB of RAM is should be safe to allocate up to 1 MB for data approximately 500 000 data points Above this number try running the instrument to verify that it operates correctly Data Acquisition Status Messages Stop On Erro
90. automatically selected In addition Histogram results cannot be stored to disk with the Disk Out element Input Channel Specifies either the Time or Frequency domain channel being analyzed Note that the contents of the Channel list only contains channels of the specified type Calculation Sum Values Adds the value of each data point within a bin Average Values Sums all data values in each bin and divides each by the number of events to produce an average value per bin Count Bin Events Counts the number of data points above the specified Threshold Page 15 18 Histogram Band Analysis Octave Band Analysis Output Type Band Analysis Histogram Output Bins Bin Width of Bins Minimum Maximum Settings Input Channel Calculation Output Bin Snap Master User s Manual Divides the X axis into the specified Bin Width or Number of Bins except for Octave Band Analysis and performs the calculation on each bin The standard Spacing setting is Linear which divides the bin width equally among all bins When a Frequency channel is specified in the Input Channel group you can perform Octave Band Analysis which divides each bin into a octaves which is a doubling in frequency or octave divisions The available octave divisions are 1 Octave 1 3 Octave 1 5 Octave 1 8 Octave and 1 12 Octave Divides the Y axis into the specified Bin Width or Number of Bins and performs the calculation on each bin When selec
91. b4 Time Channel 0 Present 2 Not Present b3 bO Data Type 0 Y vs T data 1 Y vs F rectangular data 2 Y vs F polar data 2 amp 3 b15 b0 Channels Integer 0 65535 4 to all Not used contains 0 value bytes HE If the data file contains frequency domain data then each data point consists of two consecutive four byte values resulting in eight bytes The first value is the magnitude data and the second value is the phase data DATA File Offset 4 Channels bytes Length 4 Channels Sample Points per Channel bytes Sample Group SG 4 Channels bytes Notes Each data point is a four byte single precision floating point value Intel 80x87 format IEEE 754 1985 Each sample group repeats once for each data point of every channel of every frame No frame markers are inserted Time channel values if written are accumulated across frame boundaries Byte Bit Range Description Assignment 0 to 4 all first channel s floating point Range 1 7e38 to 1 7e38 with value minimum precision of 1 7e 38 24 bit floating precision SG 5 to all last channel s floating point Range 1 7e38 to 1 7e38 with SG 1 value minimum precision of 1 7e 38 24 bit floating precision Wave Generator 5 1 WavefOFIs si isdssssccicsessccescocesssdssiecceccessscsusesesccecesesssoseseccsssesdscsesscescaesesescouceeuscousssescaeceSessousssecocesedessenseooceseses 5 2 Menur Commands sessiossa a aa aea eese esas sa
92. button as you move the mouse pointer over it as well as any Snap Master messages from the Status Log These messages include which instrument is running triggering messages and errors that may occur In the lower right corner of the Status Bar the current date and time is displayed The Toolbox located on the left side of the workspace contains the various element icons used to create an instrument When building an instrument simply click on an icon in the Toolbox then drag it over the instrument window and drop the icon Some icons in the Toolbox represent several elements of the same type such as when you have more than one A D driver installed Clicking once on the icon in the Toolbox displays a pop up menu which shows the different elements using the icon The item that has a check mark next to it is the element that will be placed in the instrument when the icon is dragged from the Toolbox and dropped in the instrument window To change the checked item select a new option from the pop up menu Snap Master Basics Instrument Window Comment Field Page 2 3 A C SM DEFUSER PEAKFIND INS olx Integrate Data Between the 3rd and 7th Peak Automatically Detect Peaks Element Icons Wave Generator B Analysis Data Pipes Figure 2 2 Instrument Window The instrument window is where the actual construction of an instrument occurs Element icons are dragged from the Toolbox and dropped in the instrum
93. channels specified in the Ch1 and Ch2 columns from the instantaneous amplitude spectrum output by the FFT algorithm In order to perform the Cross Power Spectral Density function the two channels being analyzed must have the same frame characteristics The result units are the products of the units divided by Hertz such as volts Hz or volts psi Hz This function is similar to the Auto Power Spectral Density except that two different channels are used to calculate the power common to both channels If the same channels are specified in Chl and Ch2 then the Cross Power Spectral Density is equal to the Auto Power Spectral Density of the channel E avg S S df where b the output is the channel listed in the Ch1 column a the input is the channel listed in The mathematical description for the Cross Power Spectral Density is G the Ch2 column G is the instantaneous amplitude spectral density S is the instantaneous amplitude spectrum of b S i is the complex conjugate of the instantaneous amplitude spectrum of a and df is the frequency resolution The Coherence function measures the ratio of how much power in the output signal listed in the Chl column is caused by or related to the input signal listed in the Ch2 column In order to perform the Coherence function the two channels must have the same frame characteristics This function helps to determine whether or not a system is linear at a given frequency Because the
94. collection of samples is based on the sampling frequency The Nyquist Sampling Theorem states that the input signal must be sampled at least twice the frequency of the highest component of interest Page A 8 Sample Hold S H Scroll Bars Sensor Shielded Cable Simultaneous Sample Hold Signal Conditioner Single Ended Size Box State Variable Status Log Streaming Subroutine Terminal Count T C Thermocouple Throughput Rate Token Snap Master User s Manual A circuit which acquires and stores an analog voltage on a capacitor for a short period of time Scroll bars become active when there is too much information for one window The scroll bars enable you to view this information by scrolling the displayed information within the window either up and down vertical scroll bar or left and right horizontal scroll bar The Sensor element integrates a database of the components that measures physical events and converts them to analog electrical signals Contains specifications calibration data and specifies units for the instrument When an instrument contains the Sensor element and one of the assigned sensors is past its calibration interval an error message appears in the Status Log A cable with foil or other sheathing around it to stop radio frequency interference and magnetic fields from generating extraneous signals on cable conductors A data acquisition system in which several sample hold circuits
95. contains a separate database for each set of scaling terms and the date when the calibration took place The key to the Sensor database is the Sensor ID Because this is a relational database the Sensor ID acts as the primary sort index Each sensor MUST have a unique Sensor ID which is created when you insert a new sensor from the Sensor Specifications table Page 7 2 Sensor Database Files Input And Output Values And Units Snap Master User s Manual Figure 7 1 displays the relationship between the two key tables in the Sensor element The Sensor Assignments table takes specific sensors from the Sensor Specifications table and utilizes them in the instrument Therefore the Sensor Assignments table acts as an instrument specific subset of the Sensor Specifications table Snap Master contains only one Sensor database The files containing the database information are located in the SYSDATA directory and are HISTORY DB HISTORY PX SPECS DB and SPECS PX DO NOT delete these files or move them from this directory While there is only one master database you can have multiple assignment files referencing the same database The assignments are instrument specific and always reference the master database Therefore your master database can be large but you will usually assign only a subset of the database in an instrument When you want to move instruments or Sensor Assignment files between computers you must make sure the same Se
96. cooperative multitasking system Glossary Nyquist Sampling Theorem Passive Filter PID Place Holder Polling Pretriggering Pushbuttons Radiobuttons Random Access Memory RAM Range Read Only Memory ROM Real Time Resistance Temperature Detector RTD Resolution Sample Page A 7 States that the sampling rate must be at least twice as a large as the highest frequency of the input signal otherwise aliasing will occur Aliasing is when frequencies appear that are not in the actual signal A filter circuit using only resistors capacitors and inductors No active devices such as integrated circuit amplifiers Proportional Integral Derivative A three mode control algorithm Token used in the RS 232 element to define a special string of characters that is ignored when Snap Master interprets the incoming string from an external piece of RS 232 equipment The length of the Place Holder token is ignored A round robin canvassing of data acquisition inputs synchronized in software to a clock or external trigger One of three methods of transferring data acquisition measurements to the computer s memory the others being DMA and interrupt The technique used on a data acquisition board to keep a continuous buffer filled with data so that when the trigger conditions are met the sample includes the data leading up to the trigger condition Pushbuttons cause an immediate action to be taken If the
97. dialog specifies which Y axis the selected channels are assigned to Show As Specifies if the channels are shown by Label if assigned using the Sensor or Analysis element or the channel Number consisting of the element letter and channel number This setting is also reflected in the Channel list Display Strip Charts Frequency Plots Mag vs F Phase vs F Y vs X Scatter Plots X Axis Settings Page 3 9 A Strip Chart plot simulates the action of a paper roll strip chart recorder The paper scrolls from right to left with new data plotted at the right edge Strip chart mode is most useful for lower speed data acquisition When you are acquiring data at speeds where the strip chart appears to flicker too much use the various Plotting Techniques to increase the plot s throughput and improve the smoothness of the strip chart Other than the on screen appearance of the data Strip Chart plots have the same features as Y T plots and use the same Plot Settings X Axis Settings Y Axis Settings and Channel Settings dialogs There are certain features not available for the Strip Charts which are disabled in the dialogs To use these features change the plot type to a Y T plot Frequency domain plots operate the same as Time domain plots except the X axis is now expressed in the frequency units Hertz Hz Mag vs F plots the magnitude of the frequency component relative to the frequency and Phase vs F plots the phase at eac
98. each Source edge the counter accumulates its value When the counter value reaches 0 a T C is generated and the counter value is reset to the Load register value If a new frame starts before a T C is reached the counter is reset to the Load register value After the T C the count does not begin until the counter is rearmed when a new frame begins Software Triggered Strobe with Level Gating This mode performs the same counting operation as Mode A except that the Source edge is only counted when the Gate condition is met Hardware Triggered Strobe This mode performs the same counting operation as Mode A except that the Source edge is only counted when a Gate edge occurs This differs from Mode B where the Gate condition must be satisfied for each Source edge Mode C requires only one Gate edge to begin counting Rate Generator with No Hardware Gating At the beginning of each frame the Load register sets the initial value of the counter The counter repetitively counts to T C and reloads the Load register value As a result the Load register value determines the time between T Cs When the Output is set to the T C Toggled signal a square wave is generated Rate Generator with Level Gating This mode performs the same function as Mode D except that the counter only counts the Source edges which occur while the Gate condition is satisfied Non Retriggerable One Shot At the beginning of each frame the Load register sets the ini
99. eee en esee esee tns eset ts esee tense see tnus 14 26 Building the Instrument 2 RT DERART ERU RM E ERU RUE REDE etat eig 14 26 Configuring the A D Demo Element eren nne nennen nennen enne en enne 14 27 Calculating he Eorward EET eise epe ee RODA RE 14 27 Running The Instruments 2 posae ER e eui 14 29 14 6 Tutorial Performing an Inverse FFT eese ecce cesse eee eee ee eee en eese enn esee enses etta esee tense se enus 14 29 Calculating An Inverse BET ini rn Peri Dr RO ER Pie rit Bee EPI Ae SEESE 14 29 R rmnes tlie Instrument inea peel poete deter 14 31 14 7 Tutorial Cross Power Spectrum ceres esee eese esee ene eese ena eset esas set ts esset enses etes esee tensa set enus 14 31 Adding The Second A D Dero spent tp dep ede Ute ei b piter 14 31 Calculating the Cross Power Spectrum eeseesseeeseeeeeeeeee eee enne nennen neret ennne 14 32 Runnin the lnstrumehnt tore eive t ee RU eie 14 33 Page x Snap Master User s Manual 14 8 Tutorial Transfer and Coherence Functions sssssssssssssssesssssssesssesssesssessssssesssesssesssessseees 14 34 Calculating The Transfer Functio yiera oeaan ernea imd rh edm enit rede ttg 14 34 Calculating The Coherence Function cceescsscesseessseesseecsscecssecscecsseecseecesaeeesaeesaeessaeesseeseaeeseees 14 35 Running the Instrument dee de De ns ca ut rtp edet ete cei eee nete tese rb Ce 14 36
100. element This is because in the real world the sensor converts real world events into analog voltages which are then converted to a digital signal by the A D element Therefore Snap Master maintains the logical progression of the test signals in the instrument flow chart by illustrating the Sensor as an input to the A D element A D A Sensor B 4 D Demo C Display Figure 7 11 Instrument for Sensor Tutorial 1 Create a new instrument with the button or select the File menu New Instrument command in the Snap Master workspace 2 Place the Sensor A D Demo and Display elements in the instrument If a message box appears on your screen asking you if SHARE EXE is loaded you must exit Windows and run SHARE from the DOS prompt do not run it from a DOS shell within Windows Refer to the Installation section of the manual for more information 3 Activate Pipe Mode with the button or select the Element menu Pipe Mode command 4 Connect the Sensor element to the A D Demo element and the A D Demo element to the Display element 5 Turn off Pipe Mode with the button or select the Element menu Pipe Mode command 6 Save the instrument with the button or select the File menu Save Instrument As command Save the instrument as SENSOR Signal Conditioning Page 7 11 Assigning a 1 Open the Sensor Assignments window Sensor To An In put Chan nel Sensor Assignments Untitled Beles Fie Edi View Settings Help ges e amp
101. file was created The value is enclosed in quotes and follows the mm dd yyyy format String that specifies the time that the data file was created The value is enclosed in quotes and follows the hh mm ss format Numeric value of the sampling frequency per channel Numeric value of the actual Frame Length used by Snap Master Numeric value of the number of channels of data in the data file List of strings specifying the element letter and channels in the data file Entries are separated by a comma All element letters must be the same and must correspond to the last letter in the SM file extension Numeric value of the number of points sampled per channel for each frame of data String specifying the units used for the x axis variable For time domain data the value is the units used such as Sec For frequency data the value is given as Hz String specifying the file type The settings for the different formats are as follows x 30 Interleaved Analog Exponential x 25 Interleaved Analog Binary x 29 Interleaved Analog Binary Raw Numeric value representing the interleave factor of the data points which is equal to the number of acquired channels List of strings specifying the conversion polynomial for each channel in the CHAN array In the Exponential file format the data has already been converted using these equations Each value is separated by a comma Disk I O Exponential Data File Format Pag
102. file with the Disk In element the element letters it produces depends on the format of the file For the native Snap Master formats Standard Binary Fast Binary and Exponential the element letters are the same as when the file was created For example if the data from channels AO A1 and RO was written to disk then they remain AO Al and RO when replayed If there is an element letter conflict with any other element in the instrument Snap Master re letters the elements to use an unused letter For files that are imported into Snap Master including Snap Series and generic file formats the output channels use the same element letter as the Disk In element ASCII File Import When you specify an ASCII data file such as a Comma Separated Variable or ASCII Plotter the ASCII File Import Group is activated These settings determine how Snap Master imports the data from the file in order to make the data compatible with the other Snap Master elements in the instrument Disk I O Replay Options Skip Lines ASCII File Viewer Include Channel Labels Line Auto Detect Total of Points Sample Rate Duration of Points Y Axis Minimum Y Axis Maximum Page 4 5 Specifies the number of lines at the beginning of the file to ignore Useful if the ASCII file contains a header Displays the first 4096 bytes of the ASCII file If the file contains the names of the channels in the line immediately before the data tur
103. format of the string is AppName followed by a mnm more information on sending DDE strings to Snap Master refer to Appendix D Command DDE Execute Command Case Statements Page 13 9 DDEExec DDECommandsString Example If A0240 Then DDEExec Snap Masterltest ins B MaximizeDisplay End If The DDE Execute command allows you to send a command to other Snap Master elements or other programs Most commands sent to a Snap Master element such as FileOpen do not take effect until the instrument is restarted Instead of writing a large number of nested IF THEN ELSE statements you may want to use case statements Using the SELECT CASE syntax with a state variable as the argument data channels are not supported as the argument you can write much simpler Command equations The format for a case statement is Select Case statevar Case valuel statements Case value2 statements End Select Case statements start with the key words Select Case and the single word name of the state variable Each case to be tested for starts with the key word Case along with the value associated with the case followed by a colon Any statements for the case are written after the line with the Case key word The statements for a case are finished when either another Case keyword is encountered or the complete case statement is completed with the End Select key words All case statements must be completed by an End Select
104. function produces a ratio the result has no units The Coherence function is used to characterize a system or device under test by comparing two channels such as input and output or maybe two related parameters like voltage and current or pressure and flow This helps to determine the efficiency of a system whether a system is linear and whether there are extraneous inputs to the system The coherence function is important because it is a way of validating the quality of the transfer function at each frequency FFT Coherent Output Power Transfer Function Page 14 9 The Coherence results are usually averaged over multiple FFT result frames to obtain an accurate representation of the signal A Coherence value of means that all of the output signal s power comes from the input while a value less than 1 means that there are other sources for the output power such as noise If the Coherence value is 0 then the input signal contributes none of the power to the output signal In addition if both the output and input equal 0 then the result is defined as 1 If only the input equals O and the output is non zero then the Coherence is defined as 0 Gap Ga where b the aa bb output is the channel listed in the Ch1 column a the input is the channel listed in the Ch2 The mathematical description for the Coherence function is COH column G is the Cross Power Spectral Density of a and b G is the com
105. in Snap Master When you press the button all of the data is requested from the database server There may be a delay before the data is presented on screen depending on the amount of data requested and the amount of traffic on the network To scale the data as shown above press the Auto Y Scale button Glossary A D A D Board A D Demo Acquisition Active Filter Algorithm Alias Frequency Aliasing Amplitude Analog Analog to Digital Conversion Analysis ASCII Asynchronous Background Bandpass Filter Base Address Page A 1 Appendix A Glossary Abbreviation for Analog to Digital Conversion Reverse of D A Receives data from a plug in A D analog to digital converter card Specifies the sampling rates acquisition times and other card options When this element is placed in an instrument its name changes to the model of the A D card The A D Demo element mimics the operation of a plug in A D board in Snap Master The process by which data is gathered by the computer for analysis or storage An electronic filter that combines active circuit devices usually amplifiers with passive circuit elements such as resistors and capacitors Active filters typically have characteristics that more closely match ideal filters than do strictly passive filters A set of rules or detailed plan with a finite number of steps for solving a problem An algorithm can be used as a model for a computer program
106. instrument instrument instrument instrument instrument instrument instrument instrument instrument D 14 Command Topic Item FileNew FileOpen filename FileSave FileSaveAs filename FileClose OptionsCheckNow ActiveEquation Line Definition Line Active OptionsAutoIndent OptionsAutoCase OptionsAutoCheck DecisionRate Line VariableName instrument instrument instrument instrument instrument instrument instrument instrument instrument instrument instrument instrument instrument instrument instrument Line InitialValue Reg E X c 6 RARER XO SUR Req E X c 6 LAK AANA x Poke RAK RRR RAR Poke LAR RA ASR EN Format integer string string string string string string string string Format integer string string string string string single string single Page D 17 Comments full path and file name full path and file name Left Right On Off Comments full path and file name full path and file name Yes No On Off On Off On Off Replace Line with Command Settings table row number Page D 18 Snap Master User s Manual D 15 FFT Reg Poke Format Comments E X c 6 Topic Item instrument FileNew instrument FileOpen filename full path and file name instrument FileSave instrument FileSaveAs filename full path and file name instrument FileClose instrument Line Ch instrume
107. last exited the Snap Master workspace When you close an instrument from the workspace Snap Master normally checks to see if the file has changed since it was last saved If the instrument has changed you are asked if you want to save your changes To skip the comparison and close the file immediately turn off the check box This is the recommended setting for any programs using the Front Panel Library When selected Snap Master checks for the Windows 95 task bar on the screen when opening windows from the workspace Windows 3 1 users should leave this check box unchecked Shows all Snap Master dialogs with gray backgrounds you must restart Snap Master for the changes to take effect Sets the font for the upper edit bar in all tables you must close any open tables for the changes to take effect Sets the font for the cells in all tables you must close any open tables for the changes to take effect Page 2 8 Instrument Settings Data Acquisition Settings Table Interface for Hardware Elements Number of DMA Boards Snap Master User s Manual When selected all HDI compatible hardware elements use a table interface to set up the channels When turned off the element uses the original dialog based user interface Only used while acquiring data using Hardware DMA mode Determines how much upper memory is allocated for high speed data transfer between the DMA Direct Memory Access acquisition hardware and th
108. list by either double clicking on it or by selecting an item and pressing the OK button the element is placed in the instrument Pressing the Cancel button averts putting a new element in the instrument Turn the Command Bar on or off Turn the Status Bar on or off Turn the Toolbox on or off Status Log Started instrument D SM3 DEFUSER DISPLAY INS ERROR 5 17 94 11 49 44 PM This instrument cannot be started Reason Another instrument is currently running Solution 1 Stop the currently running instrument 2 Start this instrument 5 17 94 11 49 48 PM Stopped instrument D SM3 DEFUSER DISPLAY INS lx Save As Clear Exit Help Figure 2 6 Status Log The Status Log is where Snap Master queues time stamped operating messages and errors Under normal operating conditions you will not need to view the Status Log However if an error occurs in an instrument a message is logged and the Status Log appears automatically Errors are indicated by the keyword ERROR preceding the time stamp followed by the error message Errors might include A D Overruns out of memory sensor out of calibration etc The contents of the Status Log can be saved to a text file using the Save As button This text file may be used by the technical support staff to diagnose problems Pressing the Save As button opens the standard Windows File Save dialog where you can specify the file name When the Auto Arrange function is selected
109. module a pop up menu might appear with a list of installed A D Board drivers If it does select the A D Demo option from the list A check mark indicates which driver is currently selected Position the mouse pointer on the A D board then click and hold the left mouse button When you move the mouse the cursor will change to the outline of the A D Board Drag the A D Board cursor from the Toolbox until it is over the instrument window underneath the comment field then release the mouse button The A D Demo element icon should appear in the instrument window Notice that when you place the A D Demo element in the instrument it is assigned the element letter A This letter is used by Snap Master to distinguish the channels from each element because no two elements can have the same element letter For example channel 0 will be referred to as channel AO by the other elements in the instrument Check to make sure that the text underneath the icon says A A D Demo If it does not press the DEL key to delete the element from the instrument Return to the beginning of this step remembering to select the A D Demo element from the pop up menu on the A D element icon in the Toolbox 2 Place the Display element in the instrument window Position the Display element to the right of the A D Demo element Follow the same instructions given for the A D Demo element Because there is only one Display element no pop up menu will appear 3
110. mouse pointer over the cursor s hot spot the dotted rectangular box where the cursor and data meet Press and hold the right mouse button then move the mouse to the right and left to drag it Here is another method of moving the cursor that works better for large distance moves Notice that with each move the Cursor Data window updates to the value at the current position Finding The Slope Instead of using two cursors and calculations to find the differences between two points let s Between Two Points use a Relative Cursor 1 Double click on the cursor s hot spot to open the Cursor Setup dialog Cursor Setup Channels Main Channel AO List Plotted Channels C All Channels Secondary Iv Full Vertical T Full Horizontal Skip Every 1 v points Set Cursor Color Delete Cursor Cancel Help Figure 3 41 Relative Cursor Setup 2 Change the cursor type to Relative The default mode for a new cursor is Absolute which displays one point at a time The Relative mode displays the differences and slope between two points in the Cursor Data table 3 Press OK to close the Cursor Setup When you return to the Display window the cursor now has two solid circles at the top and bottom of the plot which are called anchors The anchor defines the starting point for all difference calculations 4 Click on the cursor s hot spot and drag the cursor to the right When you drag the curs
111. of data When used with the Range function the standard deviation is calculated over the specified range only Standard Deviation is a measure of the variability or spread of the data in a channel For a normal Gaussian Bell shape distribution the likelihood that any data point will be between the average value plus or minus the value of the Standard Deviation is 68 Approximately 95 of the values fall within plus or minus two standard deviations The result is always equal to or greater than zero var argl Example SO var AO The Variance function outputs the square of the standard deviation of arg1 The output of the function is a single point which is produced after all points in arg are processed When used with the Block function one point is produced for each block of data When used with the Range function the variance is calculated over the specified range only Variance is the measure of the dispersion or scattering of a set of values around the mean While standard deviation is normally used variance is a more basic mathematical function and is used in the statistical F function All of the logical functions treat data as if it were digital in nature which means the value can only be True or 0 False For data that is not digital the function treats all data values greater than or equal to 1 as a True and all values less than 1 as False argl and arg2 Options o Oversampling u Undersampling Examples RO
112. or from the Disk In element try performing a Retrace Now with the button or change to Full Retrace Mode using the Options menu Retrace Options command Each plot can have multiple cursors markers and text annotations To move a cursor click and hold the mouse button on the hot spot indicated by a dotted outline around the selected cursor or marker to drag the cursor across the waveform In addition the left and right mouse buttons move the cursor in the increments given by the Skip Rate value in the Setup dialog box Clicking on the right mouse button moves the cursor in the positive X axis direction while the left mouse button moves the cursor in a negative X axis direction Holding the mouse button down will continue the movement of the cursor in the direction you have chosen You can link multiple cursors and markers together so they move in tandem using the Linked column in the Cursor Data table Up to 8 link groups can be defined Cursor Settings Cursor Setup Channels Main Channel AO List C Plotted Channels All Channels Cross Hair ZN Secondary Voltage A0 Global v Full Vertical T Full Horizontal Max each 10 pts P1 Global Min each 10 pts P2 Global 5 5 Integrate every 10 pts P3 GI Skip Every points Running Avg RO Plotted Running Min R2 Plotted Set Cursor Color Delete Cursor Cancel Help Figure 3 22 Cursor Setup Dialog Box To configure a cursor using the Cursor
113. plots with one exception The Background color applies only to the visible title lines in the plot because each channel has a programmable color background which is set in the Channel Settings dialog box Digital Meter Channel Settings Channel r Colors One Color Infinity To Infinity Number Format S Value J Bona z Sample 1234 123 Volts Tre Coles N A To N A Format Decimal C Scientific Value mmm Bkgnd C Engineering C Three Colors N A ToN A Digits 5 3 Value INN k on z Cancel Help Figure 3 8 Digital Meter Channel Settings The settings are separate for each channel in the Channel list You can change the settings for multiple channels by highlighting more than one item in the Channel list Number Format Format Specifies if the values are displayed as a Decimal 1234 123 Scientific 1 234e 03 or Engineering 1 234 K number Digits Specifies how many numbers are displayed before and after the decimal place Colors One Color Specifies the value and background colors for the selected channels for the range specified When One Color is selected the same colors are used for all data values Two Colors When selected the cutoff value for the visual alarm is entered at the end of the One Color line All data values up to the cutoff value are set by the One Color settings and all data values above the cutoff value are set by the Two Color Settings Three C
114. pulses may have a constant physical unit such as degrees associated with each pulse Use the Units list to select alternate values for the sampling rate or enter your own in the list If you cannot associate physical units to the pacer use a sample rate of 1 and units of Scan X Axis Label Specifies the name for the independent axis Frame Length You can define the size of each data frame by specifying either Duration based on the Sample Rate and the Pacing Units or as an absolute Number of Points The frame length is equal to the number of points divided by the sample rate A frame is analogous to the sweep time of traditional oscilloscopes At the end of each frame the A D element reinitializes itself As a result there is a break between data frames the length of which is affected by a number of factors including the speed of the computer the complexity of the instrument etc Therefore a frame is a contiguous set of gapless data acquired at the specified Sample Rate with an indeterminate gap between frames At lower sample rates the time lapse between frames may be unnoticeable Frames are used to separate the data into logical blocks For example if you only want to acquire 500 points after an error condition occurs set up a Trigger to start a frame on the error and set the frame length to 500 points Otherwise you would have to wade through a large amount of data to only look at the points of interest A frame can range
115. pushbutton is active indicated by a dotted outline around its text press ENTER to select it Press TAB to move between pushbuttons Radiobuttons are small circular buttons in dialog boxes and displays that allow you to select an option from a group of mutually exclusive items Therefore you can make only one selection at a time in a group of related radiobuttons Radiobuttons always appear in groups Use the ARROW keys to move between radiobuttons then press SPACEBAR to toggle the radiobutton Volatile storage its contents are erased when the computer loses power in which you can read and write to any desired location Usually installed as computer chips on the computer s motherboard The maximum allowable full scale signal input or output that yields a specified performance level Computer memory in which data can be routinely read but written to only using special means when the ROM is manufactured ROM is used for storing data or programs on a permanent basis A property of an event or system in which data is processed as it is acquired instead of being accumulated and processed at a later time A metallic probe that measures temperature based upon its coefficient of resistivity The smallest significant number to which a measurement can be determined For example a converter with 12 bit resolution can solve 1 part in 4096 A data point converted by the A D board from an analog signal to a digital signal The accuracy of the
116. running on the same computer as the Snap Master Network DDE The data server application is running on the specified Computer Name You may enter the network computer name of the data server machine or use the Browse button to view the available machines on the Microsoft network Server Application Snap Master Instrument When selected links are automatically created to the specified instrument When the Start Server Instrument on Client Start checkbox is active the client instrument automatically starts the Snap Master data server instrument The Stop Server Instrument on Client Stop stops data collection at the server when the client is finished receiving data over DDE Note Only one Snap Master session can run on a single machine so the Snap Master radio button will be used mostly for instances where the data server is on a separate computer Multiple DDE In data clients can connect to a single DDE Out data server Other Application When selected the specified application such as a spreadsheet or custom program is used as the data server When the Use List To Specify Topics check box is selected Snap Master makes a special DDE request to the System topic and Topics item of the application to fill the Topics column drop down list in the table Page 6 8 Frame Settings 6 2 DDE Out Snap Master User s Manual Frame Settings Pacing Type Data Driven Auto Generate Sample Rate fico 7 Sec Pacing Units
117. software vendor for more information on the technical support services they provide HEM Data offers a valuable extended support program ESP which increases the period of technical support and product maintenance for yearly periods beyond the initial four months Like our software our extended support program is designed to focus on our customers changing requirements For the duration selected the Extended Support Program includes e General support by telephone and fax e Assistance in problem diagnosis and resolution e Free minor software upgrades builds when available to correct a customer s problem or provides needed functional enhancement Upgrades distributed via either our World Wide Web page Attp www hemdata com or by snail mail e Automatic free upgrades to major software upgrades i e from 3 2 to 3 3 or 4 0 released during the support period e A subscription to our technical newsletter e Discounts on training seminars and engineering consultation The price of an Extended Support Programs depends on the software module s and period covered You must be a registered user and own the current version of the software to enroll in a support program You may have to pay an upgrade fee to bring your product up to the current version level Please contact HEM Data for current pricing or if you need more information 1 3 System Requirements In order to use this product you will need the following hardware and software
118. string table would look like the following note that these string sequences are specific to the Hydra consult the manual for your specific equipment for the proper string sequences Initialization __ RST FUNC 0 VDC AUTO n Query SCANL NEXT SCAN 0n If you were to send out this set of commands using a terminal emulator such as the Terminal program included with Windows then the data logger s response to this would look like this 8 0 0 1 1 93 7 939E 0 15 255 00 000E 3 r n gt r n As we can see from the response the Delimiter is a comma The Terminator for this string is either r n gt r n or gt r n If the Terminator was set to r n then the gt r n would be interpreted as the next response and an error condition would occur Because it is not obvious from the response what each of the tokens represent we must consult the Hydra Data Logger s manual It says that the first six tokens are the hour minute seconds month day and year respectively which would be 8 AM on January 1 1993 in the above string The seventh token is the floating point value for Channel 0 The last three tokens are the alarm output digital I O and counter values RS 232 Page 10 9 Because our example is only interested in the data in channel 0 the settings in the Instrument Response group would look like this Format HOUR MINUTE SECOND MONTH DAY YEAR CHO ALARM DIGITAL COUNTER Delimit
119. the File menu New Instrument 2 Place the A D Demo Histogram and Display elements in the instrument 3 Activate Pipe Mode with the button or select the Element menu Pipe Mode command 4 Connect the A D Demo element to the Histogram element and the Histogram element to the Display element 5 Turn off Pipe Mode with the button or select the Element menu Pipe Mode command 6 Save the instrument with the button or select the File menu Save Instrument As command Save the instrument as HISTO 1 Open the A D Demo Settings by double clicking on the element A D Settings r Pacing r Channel List Type Software z el Location CIntemal Cem Sample Rate 100 7 Sec Pacing Units Sec zl X Axis Label Time Triggers Free Running Frame Length Input Ranges 18 to 10 Volts Duration B Sec G 1t of Points po Memory standard Device gt gt Number of Frames C Continuous Sine zi Stop After fi dcs Configuration I Status Messages pec pese Figure 15 28 A D Demo Settings 2 Change the Number of Frames to Stop After 1 frame 3 Press the OK button to close the A D Demo Settings 4 Open the Histogram Settings dialog Page 15 20 Snap Master User s Manual Histogram Settings rAnputChannel Output Type Type C Time C Band Analysis X Axis C Frequency Spacing Linear aA Channel A0 Histogram
120. the Local Clipbook you must specify a Page name for the information and whether or not to share the item 9 Select the Edit menu Paste command Specify a Page name of dde test and make sure the Share Item Now check box is turned on When you are done press the OK button When the Share Clipbook Page dialog box appears use the default options and select OK There should now be a new item in the Local Clipbook window which looks like this iJ dde test The hand underneath the page means the item is shared Page 6 20 Setting Up The NetDDE Client Running the Instrument Snap Master User s Manual Now that the Snap Master data is available on the NetDDE server let s set up the client to receive the data 1 If you have not done so start Excel on the client machine 2 Open the Clipbook Viewer application on the client machine In order to access the Clipbook on another machine we must first connect to it 3 Select the File menu Connect command 4 Enter the Computer Name of the server machine the one running Snap Master or select it from the Browse list When you are done press the OK button You should now see a window that contains the Clipbook contents on the server with the EJ dde_test item This means that a valid connection exists We now need to copy this item to the Clipboard on the client so we can Paste Link it into Excel 5 Highlight the amp J dde test item then select the Edit menu Paste command 6 Swi
121. then press the Plot Settings button E 11 Press the Y Axis Settings button Utility Elements Running the Instrument Outputting All Five Frames Page 15 25 12 Turn off the Default Scale check box then change the Minimum to 30 and the Maximum to 30 13 Press the OK button to close the Y Axis Settings dialog press the OK button to close the Plot Settings dialog then press the Close button to close the Display Layout dialog 14 Switch to the Snap Master window and save the instrument with the button or with the File menu Save command Display Page 1 BEE INL Time Sec I o1 Time Sec Figure 15 39 Results of MultiFrame Tutorial When you run the instrument the data in the plot of AO appears in all frames and the data for BO appears in the fifth frame only This is due to the Output Every 5 frames setting in the Multiple Frame element If you set the value to Output Every 1 frame then you will see data in BO every frame By outputting the data every fifth frame the total amount of data plotted has been reduced from five frames to one frame Multiple Frame Calculation r Input Channel Calculation Type Time Sum i g C Frequency C Average ees Output Rate elo m oen __ Figure 15 40 Output Data Every Frame To see the difference the Output Every setting makes reopen
122. to the Lotus Intel Microsoft Expanded Memory Specification EMS versions 3 0 and higher Snap Master uses Extended Memory not Expanded Memory A plug in circuit board that adds features or capabilities beyond those basic to a computer such as a data acquisition system expansion board Data file format for Snap Master that stores raw data using ASCII text Memory above 640K that is addressable by the PC as part of the normal memory area of the computer but is not used by DOS for user programs Snap Master and Windows use Extended Memory Suffix of the file name Last three characters following the period in a file name such as xyz Can be any one two or three character name The External Box In element is a general element used to represent information that is read from an external hardware device It is most often used for devices that communicate using the RS 232 or GPIB communication protocols The External Box Out element is a general element used to represent information that is sent to an external hardware device It is most often used for devices that communicate using the RS 232 or GPIB communication protocols Calculates the Fast Fourier Transform power spectra transfer and coherence functions The results are output from this element as separate sets of data Glossary FIFO File names Filter Floating Point Numbers Frame Frequency Frequency Analysis Module Gain General Analysis Module General
123. to the line number indicated in the title of the dialog To abort the changes for this line press the Cancel button You may also use the Previous Line and Next Line buttons to navigate through the equation table without leaving the Equation Builder Page 12 6 Snap Master User s Manual Quick Function Quick Function buttons are available in both the main Equation Builder and the Function Buttons builders The available Quick Function buttons are described as follows Insert or replace the selected text with Insert or replace the selected text with Insert or replace the selected text with Insert or replace the selected text with Insert or replace the selected text with and Insert or replace the selected text with or Insert or replace the selected text with xor Insert or replace the selected text with not Insert or replace the selected text with pi Insert or enclose the selected text in EJ EE B EE EE E LE E 9 EO 9 Insert or replace the selected text with Open the Comparison Function Builder gt e Y e Open the Block Function Builder Open the Range Function Builder Define Insert or replace the selected text with define find Open the Find Time of Event Function Builder On Screen Keypad Channet R 1 O Value festa C3 Figure 12 4 On Screen Keypad The Equation Builder and the Function Builders have access to the On Screen Keypad which allows yo
124. warning dialog box will appear Utility Elements Running the Instrument Page 15 21 Before we close the Display Layout we need to configure the Y Axis for the plot of BO for a maximum of 50 data points 9 Position the selection box in the second row then press the Plot Settings button Eg 10 Turn off the Default Scale check box in the Y Axis Settings group then change the Maximum to 50 Plot Settings Histogram Title Counts vs Voltage v Show Title v Use Default Sub Title T Show Sub Title r X Auis Settings r Fonts E Item Title 1 Channel Settings Cabal Sub Title I Show X Axis Label X Label z r Y xis Settings Select Font Label Ea I Show Y Axis Label a Tex n I Default Scale tem Values Minima b o o Y Values z Maximum 50 Select Color Cance Help Figure 15 31 Histogram Plot Settings 11 Press the OK button to close the Plot Settings dialog then press the Close button to close the Display Layout dialog 12 Switch to the Snap Master window and save the instrument with the button or with the File menu Save command E Display Page 1 Be Eile Edi View Settings Start Layout Cursor Help S tss AQ vs Time Counts vs Voltage E E Jd 0 Time Sec Stopped instrument Untitled 12 3 2 5 3 1 7 T 2 S ee 11 11 97 11 47 57 AM Figure 15 32 Results of Hi
125. was conducted who conducted the test etc To create a new line of text in the field press CTRL ENTER The Print button sends the information from the Comments section of the header to the default printer Disk Out Default Settings Figure 4 10 Disk Out Defaults Show Frame Displays the current frame number in the instrument window in the caption Number of the element Show File Path Displays the complete file path in the instrument window in the caption of the element Disk I O Throughput Tester Overwriting Data Files Page 4 11 Throughput Tester Input Parameters of Channels 1 Drive C a c Sample Rate fion Jsec r Test Results Aggregate Throughput 1 94181E 07 sec Maximum Frame Length 116719 sec Maximum of Points 116718592 Test Close Help Figure 4 11 Throughput Tester The Throughput Tester allows you to see how your hard disk will perform for high speed data acquisition and how much disk space you have available For high speed acquisition you must use the Fast Binary format to achieve maximum performance To use the Throughput Tester enter the drive letter you want to write to which is any letter from A to Z and can be either a hard drive floppy drive RAM disk or network drive the of channels you plan to write and the sample rate per channel After the parameters are specified press the Test button Typically the test takes between 5 20 sec
126. wheel rotates at 16 spokes per second the apparent rotation will be reversed at a rate of 14 spokes per second from one cycle above 15 to one cycle below 15 This reversal phenomena is called folding in digital signal processing If the spoke rate is 20 spokes per second the observed phenomena would be backwards at 10 spokes per second from five above 15 to five below 15 Nyquist s The most basic principle of sampling data to produce discrete data points is Nyquist s Sampling Sampling Theorem Simply stated the sampling frequency or the number of times per second a data point Theorem is taken must be at least two times the highest frequency present in the data If there are less than two samples per cycle then there is not sufficient data to accurately define the signal For example if the data contains data up to a maximum frequency of 500 Hz then you would need to sample the data at least 1000 times per second or 1000 Hz Note that the sampling rate is defined by the highest frequency present and not the highest frequency of interest There is some probability that the data stream contains frequencies above the frequency of interest and aliasing can occur from the effects of these higher frequencies In practice sampling rates as much as ten times the maximum frequency of interest are used In many situations the presence and magnitude of high frequency noise is not known Conservative practice assumes that the signal contains data
127. you can receive data from Snap Master running on a different computer z DDE In Untitled ox File Edit View Settings Help ajea ele Z A0 P Channel Active AYES Untitled 8 Gr Mm Bag OTT d Figure 6 1 DDE In In order to receive data over DDE you must include the DDE In element in the instrument However you do not need to include the DDE In element if you are only receiving commands and parameters from another application such as a custom front panel The DDE In element acts as a data client which receives data from a data server such as a Snap Master DDE Out element running on another machine or a different application An instrument can contain multiple DDE In elements or clients to consolidate data from multiple data servers The Command Bar buttons unique to the DDE In element are Button Description Sets the DDE Conversation parameters pos Sets the sample rate and frame length Page 6 6 Table Columns Menu Commands Snap Master User s Manual In the DDE In Assignments table the Data Source set in the DDE Conversation dialog determines when the table columns are editable the Channel column is never editable Columns that are not editable appear with a red column title When the data source is Snap Master only the Active and Link Item columns are editable This is because the inform
128. your WIN INI file NOTE For most installations you will not need to change these settings If you are using any other programs which use the Paradox Database Engine these settings may already be defined In most instances use the default values provided The Network Settings group controls how you are identified on the network when sharing database files The User Name is used to distinguish different computers that are accessing the same database file PARADOX NET controls your access to the different databases only one PARADOX NET file should be available on your path Finally the Network Type defines what type of network you are running on and the Share Local Tables defines if your database files are accessible through the network The Resource Limits group defines other settings for database access In most cases you can use the defaults with the Sensor Database For more information on these settings contact technical support 7 3 Signal Conditioning ap The Signal Conditioning element controls special hardware that amplifies filters and performs other signal conditioning functions In the instrument the Signal Conditioning element is placed before an input element such an A D element In addition you may also want to use the Sensor database to assign names and additional scaling so the Signal Conditioning icon is placed between the Sensor and the input element Like the Sensor a physical connection must exist between the s
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130. 10 15 38 45 ACT FREQ 2 10 ACT SWEEP 1 2 NCHANS 1 4 CHANS 14 A0 A1 A2 NUM POINTS 3 20 CLOCK UNITS 3 Sec T LE INTERLEAVE FACTOR S 2 CONVERSION POLYS 30 UNITSS 26 Volts Vo DEFAULT LABELS 10 1 CHANNEL LABELS 34 V CHANNEL TYPES 4 yt CHANNEL RANGES 38 Sample Exponential Data File DATAINFOS 126 Board T Clock Type Internal Trigger Type Free Running Resolution 12 Bit TR 1 04 21 1992 715 38 45 Oy sae Ee Shes bya ew 0 0195312 2 48047 23 0 0390625 2 460938 1 2 0 0585938 2 441406 1 D 078125 2 421875 1 17 0 0976562 2 402344 1 D IILT7IS8y 2 382812 l1 13 D I36172 2 363281 l 113 0 15625 2 34375 1 0937 0 175781 2 32422 1 074 0 195312 2 304688 1 05 0 214844 2 285156 1 03 0 234375 2 255625 1 0 0 253906 2 246094 0 99 D 273438 2 2206552 0 97 0 29297 2 207031 0 957 D 3125 2 19 75 50 9375 D 332031 2 16797 D 917 0 351562 2 148438 0 89 0 371094 2 128906 0 87 TR 2 4 21 1992 7 15 38 45 Du cem club Hh 0 0195312 2 48047 1 23 0 0390625 2 460938 1 2 0 0585938 2 441406 1 D 0T70125 2 421875 L 17 0 0976562 2 402344 1 D ILTISS 2 382812 1 13 D I3672 2 363281 1 113 D 15625 2 34375 1 09317 0 175781 2 32422 1 074 0 195312 2 304688 1 05
131. 13 13 3 In the second row type the equation PeakCount PeakCount 1 then press ENTER PeakCount is the state variable used to keep track of the number of times we cross our peak threshold Because this count value is not contained in any data channel this is a good use for a state variable 4 In the third row type the equation CurrentPeak 1 then press ENTER The CurrentPeak state variable is used to indicate when we are above the peak threshold If we did not include this variable then each data point above the threshold would cause the PeakCount to increment We are using the value of 1 to indicate the waveform is currently above the threshold and the value of 0 to indicate the waveform is below the threshold 5 In the fourth row type End Sub then press ENTER This completes our subroutine If we wanted to include more subroutines we would write them next However we will continue with the main equations for the Command element 6 In the sixth row type the equation Zf A0 gt 4 5 Then then press ENTER This statement defines our peak threshold When channel AO goes above 4 5 volts the next set of statements are processed 7 In the seventh row type the equation Jf CurrentPeak 0 Then then press ENTER Because we only want to increment the count when we are in a new peak we need to check the value of CurrentPeak If it is equal to 0 which means the previous point was below the threshold we can continue 8 In th
132. 22 Bae ID E Pe re D Savi Pos EUREN D DE eaaa PE Re Fano rego Feu EPA Dee reo dus 5 16 Chapter 6 Dynamic Data Exchange Clipboards frei ios ERE 6 1 Dynamic Data Exchange DDB 2 2 e BERE EPOR ERU eae A N aE 6 1 DDE And Sn p MAster 5 en ie e Ee cove Pe e Ft ba steeds qa Fer Eb E eS o Pie o ERE eig ta 6 3 DDE And Other Applications tete PE pr eO UO DEO Dt EEE REEE ERNIE G 6 5 Command Bar duret ep PE liie c A IR RUPEE EE PATERE 6 5 Table Colum s nnm eri ehe mI aepo cei PED IE i 6 6 Menu Commands zioni aia aden onn eee s 6 6 Settings Menu eam eB uibs iu Eee 6 7 6 3 Tutorial Receiving Data In From A Local Spreadsheet ssscsssssscssscssscsscsseessscseesssccseessseeee OW 11 Building the Instr meht d to eoi rero eom werte ee 6 11 Configuring the DDE Conversation eese nennen nene nnen nenne enenen nns en nes etee enne aa enne 6 12 Setting The DDE In Frame Settings onde UH ea teile tee EE HERE UG te AHORA 6 12 Setting Up Ihe DDE In Chantiel 2 1e nom i e eti ote eee reet edens 6 13 Runnmus the Instr ment 15 9 auo tp re RR EERTSE E ALE 6 14 6 4 Tutorial Sending Data Out To A Local Spreadsheet 4 eeeeeeeeeeeeeeee creen e eere e eeeeees O 14 Building the Instrumeht 225 n cbr RERO e EE EE EEE REM T ORARE EC FERE CEDAR URS 6 14 Configuring the A D Demori eee mtd eee Rete itte i eens et tee uet 6 15 Copying the DDE Link inedia REPRE
133. 4 29 14 7 Tutorial Cross Power Spectrum 4 eeeeeeee eese eene ee eere esee ene sse ten esse sns esee snss esee en sss sesose see ssseseseessesesseseseesss 121 3 1 14 8 Tutorial Transfer and Coherence Functions 14 ecce esee e ee ee esee eene ee seen esse eens esee enss sse sense see eossesessoseseessss 14 34 The FFT element converts time domain data to the frequency domain for further analysis display and storage This is accomplished using the Fast Fourier Transform Besides using the FFT to view the frequency components of a signal which is used as an alternative to conventional frequency spectrum analysis the FFT element also includes other complex mathematic functions such as power spectral densities coherence transfer and transmissibility FFT Untitled BEE Eile Edit View Settings Builder Help seal Es rw x li Function Ch 1 E Window Window Window Starting DC n Frames Avg Partial Ch Type Width Overlap Point Frame Rectangular 300 0 HU No TT EESMERESERS N TRI AO JET Forward FET e FET ohiala ESSE TET Figure 14 1 FFT Equation Table Command Bar The Command Bar buttons unique to the FFT element are Opens the FFT equation builder Table Columns An FFT equation is created by filling in the columns in the FFT equation t
134. 4 9 Analog to Digital 8 1 Cold Junction Compensation 15 8 Analysis 3 8 3 10 3 22 Colors 3 5 3 26 3 28 Enhanced Syntax 12 2 12 7 12 26 Channel 3 8 Original Syntax 12 2 12 7 12 23 Comma Separated Variable see CSV Data User Defined Functions 12 27 Files ArcCosine 12 14 Command 2 11 ArcSine 12 14 Command Bar 2 1 ArcTangent 12 14 Elements 2 14 ASCII File Import 4 4 Workspace 2 4 2 6 14 1 ASCII Plotter Data Files 4 1 4 2 4 4 4 9 4 Comment Field 2 8 21 Comparison 12 19 Auto Layout 3 3 3 10 3 20 Complex Triggers 8 8 Auto Power Spectral Density 14 7 Compliance 14 10 Auto Power Spectrum 14 7 Compression 1 8 Auto Rescale 3 2 3 19 Conditional 13 9 AUTOEXEC BAT 1 6 1 8 CONFIG SYS 1 6 Average 12 16 Configuration 8 12 Running 12 16 Connecting Elements 2 15 Control Panel 2 6 Correlation 12 16 B Cosine 12 13 Bar Meter 3 12 Inverse 12 14 Pictures 3 13 Cosine 4th Power Window 14 18 Binary Plotter Data Files 4 2 4 22 Cosine Tapered Window 14 18 Blackman Exact Blackman Window 14 18 Blackman Window 14 16 Blackman Harris Window 14 15 14 16 14 17 Block 12 16 12 17 12 18 12 23 Page X 2 Counter Timer 2 11 9 1 Gate 9 14 Hold Register 9 15 Internal Pacer 9 12 Internal Pacing 9 9 Load Register 9 9 9 15 Output 9 15 Source 9 3 9 14 Cross Power Spectral Density 14 8 Cross Power Spectrum 14 8 14 34 CSV Data Files 4 1 4 4 4 9 4 21 Cursor Anchors 3 25 Cursor Cross
135. And Servers DDE Service Names Topics And Items Snap Master User s Manual Communication via DDE is accomplished through a link also called a conversation The link is initiated by the program requesting the information and is called the client The application which provides the information is called the server Once the link is established each program can send commands parameters and data to the other program As an example of a DDE conversation assume that a word processing document needs the result from a spreadsheet cell The word processor requests a DDE link making the word processor the client with the spreadsheet cell so the spreadsheet is the server Once the link is established the data is transferred from the spreadsheet cell to the word processing document While the communication occurs between two programs there is nothing preventing a third application from listening in A server can deliver data to multiple clients and a client can receive data from multiple servers If you want a single Windows program to act as both a client and a server to another program there must be at least two separate DDE conversations Because DDE is only a mechanism to transfer information between programs it is up to the destination program to interpret the incoming data Generally a DDE server application will document how the data is retrieved from it and the client application documents what types of information it will accept
136. Axis Label Time Frame Length Duration 20 Sec C t of Points 200 El Number of Frames Continuous C Stop After i Bee NM Figure 6 7 DDE In Frame Settings 3 Specify the Pacing Type as Auto Generate 4 Set the Sample Rate to 10 According to this setting the Auto Generate function generates a new point using the current value in the DDE Link 10 times per second 5 Set the Frame Length Duration to 20 seconds 6 Press the OK button to close the Frame Settings dialog Dynamic Data Exchange Setting Up The DDE In Channel Page 6 13 Now that the link to Excel has been established we must set up the client to receive the data Because we are using the list box for the topic we simply need to select the correct topic from the list and enter the item for the data channel In Excel the topics are defined as the names of the open workbooks and or sheets zz DDE In Untitled ARE File Edit View Settings Help Excel Link pi Link Item R umi i zi I IS Ai Figure 6 8 DDE In Assignments 1 Position the selection box in the first row Active column Using the drop down list in the upper corner of the table select Yes from the list 2 Position the selection box in the first row Topic column Using the drop down list select channel Book1 Sheet1 or the name of y
137. Bar Comment Field Instrument Window Snap Master ow 7 m TTE E A C SM DEFUSER PEAKFIND INS Integrat Data Between the 3rd and 7th Pe Automatically Detect Peaks IC Display Toolbox Status Bar Figure 2 1 Snap Master Workspace Command Bar Most of the windows you will encounter in Snap Master have a Command Bar located directly below the menu Each Command Bar provides buttons for the most commonly used menu commands in that window As you move the mouse pointer over a button the description of the button s function appears in the Status Bar Page 2 2 Status Bar Toolbox Snap Master User s Manual Some of the common buttons you will find throughout Snap Master are w z e 5 Description Starts and stops the active instrument Creates a new window or clears the current settings Opens an existing file Saves the current settings JNE 6 Buttons that are unique to the Workspace are 5 e 5 Description Turns Pipe Mode on or off LS JE T Turns Re Letter Mode on or off Opens the Element list dialog box Arranges the icons in the instrument window Opens the Instrument Settings dialog box Opens the Status Log Opens the Snap Master Help Contents E CU 53 a s Opens the About Snap Master dialog box igus irri b Most Snap Master windows have a Status Bar at the bottom of the screen which shows both the description of a Command Bar
138. CINE eH LT ie Se we eee M ceu d 121 13 1 day 3E 11 1147 928 01 AM Figure 12 1 Analysis Element This element is included with the Snap Master Frequency Analyzer SM FA module The Frequency Analysis element operates on the magnitude portion of frequency domain data channels using the same processing functions available in the Analysis element To convert time domain data to the frequency domain use the FFT element Phase real and imaginary representations of the data channels are not available from this element Only the enhanced syntax is supported and the phase portion of all result channels is set to 0 All references to the Analysis element throughout this chapter refer to both the time domain Analysis element as well as the Frequency Analysis element Page 12 2 Command Bar Table Columns Snap Master User s Manual The Command Bar buttons unique to the Analysis elements are Opens the Equation Builder Checks the equations for errors The button says ox when the table check is successful In the Analysis equation table all columns except the Line Number column are editable If you attempt to edit the column you will be informed that editing is not available The following columns are listed in the Analysis equation table Run Comments Equation Label Units Specifies the line number of the equation This line number is used to reference the contents of
139. Calculation essent ennerenen enne nee Running the Instrument Mm 15 9 MultiFrame 15 10 Tutorial MultiFrame eee esee eee eene eene enses enses sens sons sense snsesnsesnsesnsesnseenseenseeeneeeeeeees 12 722 Building the Instr ment 5 1 n oett Hp de P et pest dioe ebur 15 22 Summing Five Frames Into One Frame eene nennen nerenen ethernet eren eene 15 23 Running the Instrument iere ned hee i eerte ir Hee Pe Fede ee uel edes d 15 25 Outputting All Five Erame s terere tete te tte eter dece tt ee etenim end 15 25 eecccccccccccccccccccccce Table of Contents FactorySuite Chapter 16 IndustrialSQL 16 1 Connecting to the Server ssccssssssssscsscccsscsecssccseessccssessssescesssseseesseees 16 2 IndustrialSQL In Settings cscsscccsscssccsscsecsssssesssscseeessssscssssseseesssees Time Controls and Resolution ccsecccceesseeeeeeeeeeeenneeecseeeeeeseneeeeeenneeeeseas TrES VAGW iens o DR T Ett OR tected CB edat Active TAG Sich usi io e RA GALERIE EINER EIU 16 3 Tutorial Using The IndustrialSQL In Element eere Building the Instrument sss eene nennen nemen nnne Connecting to the IndustrialSQL Server Database see Activating Tags rarene E Selecting the Start and End Dates esee eene Setting the Resolution 5 Readers Running the Instrumen
140. Copy Link To Clipboard Block Mode Data Points Per Block 1 Points Cancel Help Figure 6 12 DDE Out Settings 2 Select channel AO from the Channel list 3 Select data from the Item list The data Item contains the value for each data point in the channel 4 Press the Copy Link To Clipboard button This copies the information necessary for a DDE Link to the Clipboard Page 6 16 Running the Instrument Snap Master User s Manual 5 Press the OK button to close the dialog box 6 Switch to Excel 7 Position the selection box in the cell you want the data to appear in 8 Select the Edit menu Paste Special command Set the Source To Paste Link the Text then select OK The value of the cell should change to N A REF or a number to show that the DDE Link is initialized If you are using any other DDE compatible program an equivalent Paste Link should be available for example in Microsoft Word it is Paste Special then Paste Link Consult your program s documentation for instructions on defining a DDE Link 9 Repeat steps 2 through 7 for the data of channel A1 then the rate of channel A1 Paste link the information into separate cells in Excel File Edt View net Format Tool Data Window Hep PETES Diala aliy x elelc lt le zl niu sle ciel wl ell ele l pu am a ellu ss pes eel s on i t m E Snap MasterT Untitled 2 B AD rate A C
141. E Disk In Settings Snap Master User s Manual The Disk In element read data from a previously stored file into the instrument These data files are usually in one of Snap Master s native file formats Standard Binary Fast Binary or Exponential Disk In also imports data files from Snap Series as well as various generic ASCII file formats Disk In Settings examb1 dat c sm defuser 52110282 dat ETS Cancel E sm S defuser Help zd Replay Options cap B Disk In Defaults File Format Drives Snap Master Data dat 7 c hardly File Comments ASL File Import Skip Lines 0 ASCII File Viewer File Info Iv Include Channel Labels Line 3t of Channels Network Jv Auto Detect Total of Points Sample Rate 1000 Sec Y Axis Minimum 10 Duration B Sec Y Axis Maximum 10 of Pomnts 2000 Figure 4 2 Disk In Settings The Disk In Settings dialog box specifies the data file being replayed and its format The upper half of this dialog operates like the standard Windows File Open dialog boxes The File Name field specifies the data file to be replayed from the specified Directory the default directory is SM DEFUSER To specify the type of file select the appropriate choice from the File Formats list When you select a File Format the extension is automatically placed in the File Name field and the current directory is scanned for files with that extension When you replay a data
142. E 32 Min EL XS Default Plot Templ tes 3 nino HD HH ED E EUER E rash PEDES DERE Reik 3 3 X VS SIE Plots S ood itte visa tA et Eee trt dd 3 3 Strip Charts nune eese ut m estu 3 9 Frequency Plots Mag vs P Phase vs E i iieieie tepore ettet eee EE eri oie 3 9 Y yS XS Catter Plots eso re EE etes dva ifie A AE a d NET 3 0 Digital Meters nione Pese et oe tenet yet emp relenid 3 10 IGI Dolor RIP u E ES Bar Meters Dial Meters Histogram Plots iugo ap n HR PREPARED HER E A EE ER AERA AERE 3 15 3 3 Menu Commands ee eeee esee eese eee e ene sese ena esee en assesses ee sens sse eo sesso snos see soss esos osse ee eesseseessssecessess 3 16 Bile Menu ires etse tete eI eee ics eU ics wah NL Lee oS eMe ee Edit Menu eene EI envi Me I E te View Menu sabes ui x M RE M LIA s Settings Menu 5 Start Menu iie Ie EBD eu NV dip ic IT Layout Meni ooo e tt iet tea tentes tec MN Pa ut base ele A Det d Unt ext eu ot caus Mahan tebe dus Cursor Menu sienes deed ene DP eade ie rH Table of Contents Page iii 3 4 Tutorial Changing the Display Settings cssccssssssscsscsssccsscseecsscsseessscssessssesesssssesesssscssessssees 3 29 Changing Dime Colors and Styles cess ete nep odes seated eit tuted eee ges erates 3 28 Deleting and Inserting Plots ii ee nea D e e pate t E cabe Fee a eee dd ee HR E o 3 30 Overplottins Multiple Chann
143. Equation F ble Columns undrni pude P optato e P RE M epi HE FM E Sai 13 1 13 1 Menu Commands eee ee ee eee eee eese senses sensns etos sense ense ense sn sesnsesnsesnsesnsesnseenseenseeeees 13 2 MIeW3SS Aes toc RM SE EE R ER ROE E a A E A ARE 13 2 Setting AEE EEEE EEE E A E TA E TT 13 2 13 2 Command EquationS sseeessoeosssoessssecessoesessocsessoesssscesssoessssoesssssessssoeesssceessosesssoessssosssssesssssesssssessss 1373 locii iM a e S 13 4 Result Channels and State Variables sss eene nennen 13 4 Comparisons m orones i DIR RI Fences Das sada ena edo Cavs tea dee elo a S e ouk Pols etl e rer easiest 13 5 Losical Functions iin ene Pep eth n pd A REOR eR 13 6 SaN DLO SE E EEES eee tee noc Mn ar rU ANLE LU 13 7 Case Statements tutos A RR RERO OW ES T RA EVE RAAN T RE ERST REV ER LEES 13 9 13 3 Tutorial Creating A Trigger To Stop 14 eeeeeee ecce eese eee eene ee eene esee ees esee esse sees sseseesessees 13 9 Building the Instr ment 23 5 te He d ep eedem ebd 13 9 Writing A Command Routine ite IS ERR eleme ier deel oe ERR e ae 13 10 Turning Off Status Messages For The Instrument essen nennen nennen ener 13 11 Ruining The Instrument eto nde eere t e o eH Dee Deere cort Ee Pep E NEUE RR 13 11 13 4 Tutorial Subroutines and State Variables eere eee eee eee eene een eene enneenneeeeeeees 13 12 Defining The Equation Table ne
144. Error Messages 2 6 Event Counting 2 11 Exact Blackman Window 14 18 Excel 6 11 6 14 Exponential 12 13 Exponential Data Files 4 1 4 2 4 17 Exponential Window 14 19 Extended Cosine Bell Window 14 19 E Fast Binary Data Files 4 2 4 11 4 20 Fast Binary Format 1 8 FBDF see Fast Binary Data Files FFT 14 27 14 29 14 32 14 34 Forward 14 7 Inverse 14 7 FFT Noise Floor 14 5 File Comments 4 7 4 10 File Names Ordinary 4 13 Fill Regions Bar Meter 3 13 Filter FIR 12 20 IIR 12 21 IIR Family 12 21 Smoothing 15 12 Smoothing 12 20 Windows 12 21 Filters 2 11 Find Time Of Event 12 20 12 23 Flat Top Window 14 20 Fonts 3 5 Fraction 12 25 Frame Characteristics 2 16 12 9 Frame Length 2 21 2 22 8 5 12 26 13 2 Frame Time 12 22 Frames 2 16 2 21 4 15 Number Of 2 21 5 9 Frequency Analysis Module 15 17 15 22 Full Retrace 3 22 Function Builder 12 7 Function Defaults 12 8 G Gaussian Window 14 20 General Analysis Module 15 17 15 22 Global Settings Workspace 2 7 Grid Lines 3 7 H Half Cycle Sine Window 14 20 Hamming Window 14 21 Hann Window 14 21 Hanning Poisson Window 14 21 Header 4 1 4 15 HIMEM SYS 1 6 Histogram 2 11 3 15 15 17 15 19 I Icon Spacing 2 6 If Then Else 12 19 Impedance 14 10 Indicators 3 12 Input Ranges 8 9 Installing Software 1 6 Instrument Settings 2 2 Instruments 2 1 2 3 Integration 12 15 Over A Range 12 23 X Y 12 16
145. FT element and the Display element The instrument we will use for these tutorials is shown in Figure 14 9 A D 4 A D Demo B FFT C Display Figure 14 9 Instrument for Frequency Analysis Tutorials 1 Create a new instrument with the ay button or select the File menu New Instrument command in the Snap Master workspace 2 Place the A D Demo FFT and Display elements in the instrument 3 Activate Pipe Mode with the button or select the Element menu Pipe Mode command 4 Connect the A D Demo element to the FFT element and the FFT element to the Display element 5 Turn off Pipe Mode with the button or select the Element menu Pipe Mode command 6 Save the instrument with the button or select the File menu Save Instrument As command Save the instrument as FAEX1 FFT Page 14 27 Configuring the area Pacing gt Channel List A D Demo Element Type Software EZ A0 Al Location Intemal Cem Sample Rate po Sec X Axis Label Time Triggers Free Running peloh EEEE insu Hanges 10 to 10 Volts Duration j Sec C tt of Points 200 Memor standard Device Number of Frames C Continuous Sine zl CStopAfter frames Configuration r Status Messages een ee Figure 14 10 A D Demo Settings 1 Open the A D Demo element by double clicking on the icon in the instrument window 2 Change the Sample Rate to 50 3 Change the Number
146. Function Builder 15 Press the OK button to close the Find Function Builder and return to the Equation Builder 16 Press the OK button to close the Equation Builder 17 Position the selection box in the third row Comments column Using the keyboard type Find Event then press ENTER 18 Position the selection box in the third row Label column Using the keyboard type AO lt 0 then press ENTER 19 Position the selection box in the third row Units column Using the keyboard type Points then press ENTER 20 Switch to the main Snap Master window and save the instrument using the button or the File menu Save Instrument command El Display Page 3 Bee Fie Edit View Settings Start Layout Cursor Help AAMC cn tlele noe e AQ vs Time Frame 1 Digital Meter AD Volts ENS S0 51 000 Points Time Sec 2 11 11 97 10 02 41 AM Figure 12 24 Display Window with Find Results When you Start the instrument you should see the results shown This Display window shows a Y T plot for AO and a digital meter for SO You can verify the point number where channel AO drops below zero using a cursor or marker Analysis and Frequency Analysis Page 12 37 12 7 Tutorial Integrating Over A Specific Range Of Data Building The Equation Performing an integration in Snap Master is a fairly straight forward task When you combine a function with the Ran
147. Generator table all columns except the Output Channel column are editable If you attempt to edit the Output Channel column you will be informed that editing is not available The following columns are listed in the Wave Generator table Output Channel Active Waveform Stage Length Stage Units Channel Label Channel Units The element letter and channel number of the waveform stages Specifies if the data for the Output Channel is sent out of the Wave Generator element Sets the waveform type Double click on this cell to open the Waveform Settings dialog Sets the length of the waveform stage expressed in Stage Units Double click on this cell to open the Stage Length dialog Specifies the units used to set the Stage Length Specifies a long name for the channel This label accompanies the Output Channel number for use in the Display element and in data files Editable only in the first line of the channel Specifies the units of the Output Channel The default units are Volts Editable only in the first line of the channel The following waveforms are available in the Wave Generator element Ae N attt Amplitude Modulation Bessel Constant WANV TW 2 Cosine Frequency Modulation Ramp AVV AWWW Vu Sawtooth Sine Sinc WUUUL Uu ANM Square Trapezoid Triangle White Noise Wave Generator Page 5 3 H Amplitude Modulation Settings A m p l l t u d e Amplitude Modulation Parameters H Carrier Modulator
148. Hardware Settings Selection 1 CIO DAS16 330i __TimeBase _ Model CIO DAS16 330i zl DES Available Modes Software Hardware Input Type Hardware DMA ass Base Address 300 M Calibration DMA Channel 1 zl Mega Filo Interrupt IRQ 5 zl Mux Panels Figure 8 10 Device Configuration For Snap Master to properly communicate with your hardware you must specify the correct Configuration for the selected device For each of the settings available in the dialog each piece of hardware must have its own unique settings The appearance of the Configuration dialog and the available options may differ for your hardware Model Available Modes Base Address DMA Channel Interrupt IRQ Specifies the hardware model for the current device Lists the available pacing modes for the hardware Specifies the base address for the device expressed as a hexadecimal value if applicable Specifies the DMA Channel for the hardware if applicable Specifies the Interrupt Request channels for the hardware if applicable Data Acquisition 8 3 Digital In DIG IN Digital In Settings Page 8 13 The Digital In element reads data from the digital input ports on your acquisition hardware Because you can use multiple acquisition elements in an instrument you can acquire both analog and digital data simultaneously This hardware and all input devices must be properly configured in both hardware
149. Hz aggregate If you attempt to replay a file too quickly you could receive an overrun error from the Disk In element so slow down the replay rate The actual performance is dependent on your computer system and the complexity of the Snap Master instrument Letter Re mapping The Letter Re mapping feature allows you to change the element letters of the incoming data files This is accomplished by assigning an Original element letter to a Mapped letter This can be useful when trying to replay multiple data files that have the same source element letters such as two data sets containing SMA files For example the dialog box shown in Figure 4 3 changes data with the element letter A to use element letter M For example assume the data saved in this file came from the element letter A Using the Letter Re mapping feature of Disk In channel AO appears as channel MO in this instrument This is useful when trying to replay multiple data files that have the same source element letters such as when the A D element is consistently element letter B in all of the instruments used to acquire and store the data Disk I O Page 4 7 Default Settings Carei _ new Figure 4 4 Disk In Default Settings Show Frame Displays the current frame number in the instrument window in the caption Number of the element Show File Path Displays the complete file path in the instrument window in the caption of the element File Comments Read File Com
150. Inverse FFT 4 In the Result Channel text box type GO 5 Select Inverse FFT from the Function list Notice that when you select the Inverse FFT function the Input Signal list shows only the frequency domain channel Also notice that the items in the Window and Result Frame Settings are disabled This is because these selections are invalid for the Inverse FFT function 6 Select channel FO from the Ch 1 list 7 Press the OK button to close the FFT Equation Builder 8 Close the FFT equation table using the File menu Close Equations command 9 Save the instrument with the button or with the File menu Save command FFT Running the Instrument Page 14 31 Display Page 1 BEES Eile Edit View Settings Start Layout Cursor Help AO vs Time Frame 1 2 AO Nolts zi Time Sec GO vs Time Frequency Hz 5 G0 Volts 5 2 Time Sec 4 Figure 14 16 Results of Inverse FFT When you start the instrument the data for channel AO appears on screen in real time When the end of the 200 point window width is reached the FFT is calculated and output in the FO vs Frequency plot in the upper right of the Display window After the FFT is calculated then the Inverse FFT can be calculated which is output in the plot of GO The reconstruction of the waveform in channel GO is identical to the original
151. K Kaiser Bessel Window 14 22 L Letter Remapping 4 6 Linked Cursors 3 19 3 22 3 25 Linked Zoom 3 18 3 23 Locked 3 10 Log Plots 3 3 Logarithm 12 13 M Macro 12 41 Magnitude vs Freq 3 9 Marker Settings 3 26 Markers 3 2 3 3 3 25 3 38 6 4 Page X 3 Maximum 12 17 Running 12 17 Memory 8 9 12 8 12 23 Military Time 3 6 Minimum 12 17 Running 12 17 Mobility 14 11 Modulus 12 25 MultiFrame 2 11 Multiple Frame Calculations 2 11 15 15 15 22 15 23 Multiple Select Tables 3 23 Multiplication 12 12 N Natural Antilog 12 13 NetDDE 6 7 6 18 Network 6 5 6 7 Noise Floor 14 5 Number Format Data Files 4 9 Number Of Frames 2 22 8 6 8 14 9 7 Oo Octave Band Analysis 15 18 Online Help 2 9 On Screen Keypad 12 6 Overplot 3 21 3 31 Overrun 2 6 Oversampling 12 10 Overwriting Data Files 4 11 P Pacing 2 20 Panning 3 2 3 17 Parabolic Window 14 22 PARADOX NET 7 7 Parzen Window 14 22 Paste Link 6 5 6 9 6 16 6 17 Phase vs Freq 3 9 Pi 12 26 PID 1 2 PID Control 12 28 Pipe Mode 2 2 2 18 Plot Defaults 3 3 Plot Settings 3 24 Plot Templates 3 3 Plot Title 3 23 Plot Types 3 3 3 23 Plotting Techniques 4 13 Poisson Window 14 23 Power 12 12 Pre Triggering 3 6 4 17 8 9 Printing 3 2 3 16 3 17 Pulse 12 26 Page X 4 Q QEMM 1 6 Quick Function Buttons 12 5 12 6 R Range 12 16 12 17 12 18 12 22 Read Data Files
152. Letter Mode you can change the element letter for any element icon in the instrument To activate or deactivate Re Letter Mode select the Elements menu Re Letter Mode command or Al press the km button in the Command Bar When Re Letter mode is active the mouse pointer changes to IT To change the element letter of an element use the following procedure Click on the element you wish to change This opens the Re Letter dialog box The current element letter is selected in the dialog and all element letters that are already in use are inactive i CA c8 cr Cp CE CE C amp CH CL CJ CK CL CM CN fo CP Ca CH Cs CI CU CX WI NE X we Cancel Help Figure 2 4 Re Letter Dialog Box Select an available element letter then select the OK button NOTE If you change an element letter then you may need to tell the other Snap Master elements Most elements retain the reference to the original channel in the case that the channel is re used in the instrument If you do not want to use the old element letter you will need to make the reassignments Page 2 6 More Elements View Menu Command Bar Status Bar Toolbox Status Log Settings Menu Auto Arrange Snap Master User s Manual Elements Thermo Couple Linearizer Smoother Command Cancel Help Figure 2 5 Element List The Elements dialog lists all of the available elements installed in Snap Master When you select an element from the
153. Lines Side Lobe Height BSSR Bees BO Best Case 3 6 0 dB 117 7 dB SBSSR Eee SBS Worst Case 14 58 5 dB 56 96 4 dB The Hann window exhibits excellent best case response with a narrow main lobe and 60 dB bandwidth The worst case has a wider main lobe though most of the energy is below 60 dB Side lobe height in both cases is negligible Hanning Poisson Frequency Response 60 dB Bandwidth Spectral Lines Main Lobe Width Spectral Lines Side Lobe Height BSSe Bees BO Best Case 21 131 93 9 dB BSSe Bee eB Oo Worst Case 35 6 dB The Hanning Poisson window has a consistent 60 dB bandwidth between the best and worst cases but the side lobe height in the worst case is much higher than the best case In addition the width of the main lobe is wider in the best case even though much of the energy is below 60 dB Page 14 22 Kaiser Bessel Frequency Response 60 dB Bandwidth Spectral Lines Main Lobe Width Spectral Lines Side Lobe Height BSSR Bees BO Best Case 7 56 4 dB 121 9 dB BSSR Ee eSB OS Snap Master User s Manual Worst Case 6 31 4 16 85 6 dB Like the Hanning Poisson window the Kaiser Bessel window has a similar 60 dB bandwidth between cases The main lobe is wider in the worst case but the difference between the best and worst case is not as great as with other cases Parabolic Frequency Response 60 dB Bandwidth
154. M S etc The output of the sensor when the Input Min value is applied expressed in Output Units The output of the sensor when the Input Max value is applied expressed in Output Units The units for sensor output such as Volts or Amps The class of sensor such as pressure thermocouple etc The type of sensor such as Type K flow etc The next date when the sensor is scheduled to be calibrated If the sensor is used in an instrument past this date an error is sent in the Status Log Please refer to Chapter 2 for a description of the common menu commands View Menu Assigned Shows only those sensors that have been assigned to a channel All Shows all available sensors Settings Menu Sensor Specifications Sensor Specifications E isk ej Insert New Sensor Edit Sensor Delete Sensor Calibration History JL Max ID ee Kind sr Manufacturer Serialit Factor Offset Ir Displacem Encoder E AcceleraticPiezo DAC EPS 35 11 B1F Displacemi Dpitical Dyna 0 00 Dynamics DisplacemDpical i Dl 0 000 EP 2165 load 8 soma GD 2169 270 283 0 330 27 EP2795 Torque 5 8 Delphi Saginaw EP2795 1 740 0 005 a a i AAAS ARAA Automatically Calculate IE Factor ffset Input Range C Output Range ie Figure 7 4 Sensor Specifications Dialog Box The Sensor Specifications is the master table containi
155. Name is also included in the element s icon title To open this dialog select the Configuration button from the Settings dialog COM Port Settings Port Select the serial port the instrument is connected to There can be only one instrument per serial port Baud Rate Specifies the baud rate of the incoming data This setting must match the rate at which the external equipment sends and receives ASCII data and commands Data Bits Specifies the number of data bits the equipment uses for communication Parity Specifies the parity the instrument uses for communication Stop Bits Specifies the number of stop bits the instrument uses for communication Timeout Specifies the maximum amount of time in seconds that Snap Master attempts to communicate with the external equipment If this time period elapses and no communication takes place an error occurs and is recorded in the Status Log This time out should be greater than the Sample Interval Handshakin The RS 232 element provides three methods of serial communication handshaking which can be used alone or in combinations Xon Xoff is a software handshaking technique supported by many instruments and the Xon and Xoff characters supported are Control Q and Control S respectively RTS CTS and DSR DTR are hardware handshaking techniques which require proper cables Consult your equipment s manual for handshaking support Page 10 8 Snap Master User s Manual Modem Support The Mode
156. OEXEC BAT before using the FBDF format 1 6 Start Using Snap Master This manual is designed to give you an overview of Snap Master s components and how they work together Many basic examples are provided along the way to help get you started These tools will help you construct your more complicated tests in less time using Snap Master Enjoy Snap Master Basics Page 2 1 Chapter 2 Snap Master Basics puBUerudep T 2 1 p urna M H 2 10 P Ms e 2 15 2 4 Tutorial Creating Your First Instrument e eeee esee eee ee eee enses etes eset tna a setas sees en asset tenes set ens esee tens esee ees ss eeno 2 16 2 5 A D Demo Element crees ecce e eese eee teen esset en assets assesses estne eset enses sesta assetto asse tens asse senses estes sss tees esse tes assesses ese ena 2 20 2 6 Tutorial Changing A D Demo Parameters 1 eee eee esee eese eene enses teens see tn asset essa set en asse stesse sesta esee sense see enss se eto 2 21 2 1 Workspace When you start Snap Master the main workspace appears The function of the workspace is to hold the instrument windows and to provide an easy way of building new instruments The workspace has its own title bar and menu as well as other key features as shown in Figure 2 1 Command
157. Pass and Band Reject use the f2 parameter The available types are as follows Type Syntax Description Low Pass l Pass frequencies below f1 High Pass h Pass frequencies above f1 Band Pass p Pass frequencies between f1 and f2 Band Reject r Pass frequencies below f1 and above f2 Analysis and Frequency Analysis Page 12 21 Finally the window specifies the scaling function applied to the incoming data to improve the response of the filter The window parameter may be omitted in which case the default window type is used The available scaling windows are as follows Type Syntax Description Hamming M For a complete description on Hann N scaling windows and the response Blackman Harris B of each window type refer to Kaiser Bessel K Section 14 3 Rectangular R IIR Filter iir order type f1 f2 family p1 p2 arg1 Delimiters order Value between 1 and 20 type Frequency response shape f1 f2 Corner frequencies family IR filter performance pl Maximum Pass Band Ripple in Decibels p2 Minimum Stop Band Loss in Decibels Example RO iir 3 L 20 E 1 1 A0 The IIR Filter model is designed to closely match classic analog filters As a result IIR Filters have sharper cutoffs but introduce phase distortion which means the overall shape of the waveform is altered FIR filters do not have phase distortion so the waveform is preserved There are between five and seven parameters depending on the type and family which must be specified
158. Purpose Interface Bus GPIB Graphical User Interface GUI Hardware Hexadecimal Icons IEEE 488 Impedance Instrument Window Page A 5 A First In First Out memory buffer the first data stored is the first data sent to the acceptor Windows uses the MS DOS file system and has the same file naming rules Filenames can be up to eight characters in length and include a three character extension The Filter function removes unwanted frequency components from incoming data Data can be input from disk files acquired using the Data Acquisition Module or generated using the Waveform Analyzer module The results are output as a separate set of data Numbers that contain decimal parts or are presented in scientific notation digits multiplied by a power of 10 Also known as real numbers Integers are a subset of reals containing whole numbers only A contiguous set of data Number of times an alternating waveform goes through a complete cycle in one second measured in Hertz cycles per second Snap Master module which performs Fast Fourier Transforms calculations using complex numbers and digital filtering Data can be input from disk files acquired using the Data Acquisition Module or generated using the Waveform Analyzer module The amplification of a signal often used on AD boards Different A D boards allow for different gains on each channel Always remember to reference the data to the specific gain of the input c
159. R Generic Data E163 dcbet atem tte nite tbt tabicee Data File Naming Conventions 2 pg ise Input e ERO E Pe ER SD ERI EUER PHAR eee lakers 4 2 Disk In eeeeeeeeeee Disk In Settings Disk O f Setting MEC L rH 4 8 Overwrnting D t Files inre Er E ote or epe relatu e 4 11 4 4 Tutorial Saving Data To Disk ceeee esee eene esee eene ee eere esee eene sees ns esee sens esos ossseessseseesesseeess sss Fa 12 Building the Instrumeht tette rere e RH RORIS eateaes Specifying The Data Pile Names nee pr ee e er PER ERES DER Ere RE ERE ER DEEP Runnitig Phe Instrument 3a eoe rq eec RR S Pr Exp es i e bus 4 5 Tutorial Reading Data From Disk Building the Instruments 2 annee ra Rui XR TRA RACE AUS Specifying The Data Pile N m mones enee 2B Rennes hide d kien Peel reed de EE Ee reet Running The Instrument oia rere t ett rr ree er o P ri DRE t tein 4 6 Data File Formats eese eese eee eese estes eene sten sensns senses senses sess ees ses siera terii d 15 Data File Structures sateen seis ave ele enel eere Hu Re lie ines ioo ce eei ERES 4 15 Header Infotfn tion 2 i o eet tte et tine tu tet t eee oett ee E aan eed 4 15 Exponential Data File Format 0 cccccesccccessceeesceeceeseeeeeaeeeceseecesneeeseseeeeseeeeceseeeeesneeeeneeeessneeeeneeeess 4 17 Standard Binary Data File Format 00 ceeseeesee
160. R SIZE x Used only with FBDF files Integer specifying the cluster size of the disk that the file was written to PRE TRIGGER PTS x Specifies the number of points in each frame before the actual trigger event Used for plots to place time 0 of the frame at the trigger event DATAINFO x List of strings that provides the user information about how the data was acquired Exponential data files are saved as text files which can be read by other programs and by people using the TYPE command or a word processor While these files are the easiest to write they also require the most disk space of the file formats and require more time to replay into Snap Master If frequency data is contained in the file the FFT BLOCKSIZE parameter is always 1 for Exponential data files This means that the magnitude part is always followed by the phase part for each data point The data is written as interleaved floating point numbers After the header the Frame Header is written with a TR which indicates a new frame the frame number a carriage return the date the frame was started in mm dd yyyy format enclosed in quotation marks the time the frame was started in 24 hour format of hh mm ss enclosed in quotation marks and a carriage return The data is written using ASCII text and each data value is separated by a comma Page 4 18 Snap Master Data File 17 COMMENT 9 A comment DATES 12 04 21 1992 TIMES
161. Result Page 14 26 Snap Master User s Manual To illustrate the importance of the window width Figure 14 8 shows the results of a Forward FFT of a 50 Hz and a 60 Hz sine wave using the Rectangular window type The sample rate of the source data was 1000 Hz and the window width was 1000 points producing a spectral line at every 1 Hz This corresponds to the best case for the Rectangular window which should produce good results for each waveform For the 50 Hz waveform we see the results we expected There is a sharp peak at 50 Hz with little side lobe intervention However the 60 Hz signal looks more like the worst case If we drag a cursor over the 60 Hz response we see the peak appears at 62 and 63 Hz Looking at the data on the right side of Figure 14 4 8 shows us why the discrepancy exists For the 50 Hz waveform the start and end points are equal This maintains the periodicity assumption of the FFT algorithm For the 60 Hz waveform the start and end points are not equal so there is some frequency smearing present As a result our so called worst case also applies to instances where the window does not force the start and end points to zero 14 5 Tutorial Performing a Forward FFT Building the Instrument In addition to these tutorial sections there are a number of sample equation files included with the Frequency Analysis module that you may use for reference These tutorials use the A D Demo element the F
162. Retrace for Analysis produces the same results as a Buffer Retrace The main drawback of the Full Retrace is that it is slower than a Buffer Retrace Also Analysis equations are not recalculated during a retrace so the information in the Block Size is the only data available In addition you must start the instrument before you can perform a retrace Begin operation of the instrument When the instrument is running only a Stop command appears in the menu When the Display is the active window pressing the SPACEBAR on the keyboard acts as a Start and Stop command Display Page 3 23 Layout Menu 4 m E M Bd Inseit Delete Plot Settings Channel Settings Page Settings FFFRFPPPPB Plot Type Ch 1 Ch 2 Ch 3 Ch 4 Ch 5 Ch amp ys JAD H i On U U u it D D D nel D iu Close Help Figure 3 20 Display Layout The Display Layout table defines the different plots used in the different pages and which channels are assigned to the plots To use the Display Layout table position the selection box on the field or fields you wish to change Pull down the selection list located in the upper left corner of the table to view the available options To select one of the available options double click on it The Title column does not have a selection list so simply type the title for the plot The tab
163. Running Minimum function outputs the last point in argl that was closest to co If the current point is the new minimum then the output of the function is equal to the current point otherwise the output of the function is the previous minimum The output of the function has the same number of points per frame as argl rms argl Example SO rms A0 The RMS function finds the root mean square of argl The output of the function is a single point which is produced after all points in arg1 are processed When used with the Block function one point is produced for each block of data When used with the Range function the root mean square is calculated over the specified range only RMS values are often used to measure the effectiveness of a signal in a system such as the effectiveness in the transfer of power and energy rrms argl Example RO rrms A0 The Running RMS function calculates the current root mean square value based on the current and all previous points in arg1 The output of the function has the same number of points per frame as argl Page 12 18 Standard Deviation Variance Logical Functions AND OR Snap Master User s Manual std arg1 Example SO std AO The Standard Deviation function finds the deviation from the mean of arg1 The output of the function is a single point which is produced after all points in argl are processed When used with the Block function one point is produced for each block
164. Settings Load Register p Hold Register mm Counter UM Count C Down Up Function C Internal Pacer T C Reload Load Only C Load 4 Hold Usage Pulse Count gt Cycle Once Repeat CMode F F Format Binary C BCD C Custom Special Gate Disabled C Enabled Cancel Help Figure 9 2 9513 Setup The 9513 Setup dialog is used to set up exactly how each channel of the available 9513 chips is configured To open this dialog select the Device menu Hardware Settings command and press the 9513 Setup button Because a change in these settings usually requires a change in the hard wiring configuration the 9513 settings are NOT stored in each instrument file they are stored in the hardware configuration file If you want to keep multiple 9513 configurations without setting them up by hand each time you will need to save backup copies of the CNF files the hardware configuration files located in the DEFUSER directory Configuration 9513 Chip Prescaler FOUT Enabled Selects which 9513 chip is being set up in the dialog Some Counter Timer hardware has more than one 9513 chip which increases the number of available counters The Prescaler is a four stage frequency divider called F1 through F5 fed by a master clock located on the Counter Timer hardware for CTM 05 compatibles the clock frequency is 1 MHz The divider is either in Binary divides each stage of the frequency divider by a fa
165. Snap Master Display window and the Excel window so you can view both at the same time To start the instrument switch to the Snap Master Display and press the Start button While the instrument is running switch to Excel and change the value in the cell specified for the link item As you change the values the plot in Snap Master keeps up with your changes Remember that in Auto Generate mode set in the Frame Settings the DDE In element generates a new data value at each interval specified for the Sample Rate In Data Driven mode a new point is generated by the DDE In element only when the data in the link changes Try experimenting by changing the Pacing mode to Data Driven to see this effect 6 4 Tutorial Sending Data Out To A Local Spreadsheet Building the Instrument This tutorial discusses how to create a simple DDE data link sending data from Snap Master to Excel Of course any DDE aware Windows application can be used in place of Excel including other spreadsheets word processors databases or a custom application Before continuing the tutorial make sure that Excel is currently running If you do not have Excel you can use any application that accepts DDE information For consistency this tutorial assumes that Excel is receiving the DDE data A D m 4 A D Demo B DDE Dut Figure 6 10 Instrument for DDE Out Tutorial 1 Create a new instrument with the ay button or select the File menu New Instrument command in t
166. Source Ch Li Ch Label Factor Offset Input Input Eng Output Output Min Max_ Units m B 6 000 119 000 5000 000 5000 000 counts itr oni s 5000 000 5000 000 count A188 7 1193409124 A34 0212 Volt Disnlace finlical 18 8 38 4 11 10 97 3 37 51 PM Figure 7 12 Sensor Assignments Window 2 Position the selection box in the Ch column of the row where the ID is HEM 001 Pull down the list in the upper left of the table and select BO from the list by double clicking on it The Ch column is where you assign the sensor specified by ID to an input channel on the A D Demo Remember that the A D Demo is the B element in this instrument and we are acquiring channel 0 hence the BO assignment When you have multiple channels in an instrument it is not necessary to assign all of the input channels to a Sensor For example if you are using six channels of input data with sensors connected only to channels BO and B3 you only need to assign those channels to the correct sensor in the database The remaining four channels are assumed to be directly input to the A D element 3 Move the selection box to the Label column in the same row and type Sample Ch By assigning a Label to the channel we can now have a more descriptive name for the channel than simply BO This label will be passed to the Displ
167. Technique Mode combo Plot TechniquePoints integer Waveform plots only Plot TechniqueDraw string contents of Plotting Technique Draw combo Waveform plots only Plot TechniqueRate single Single Value plots only Plot ShowLegend string None Inside Grid Right Margin Plot ShowFrameNumber string Yes No Plot IndicatorShape string contents of Shape combo Indicator plots only Plot DefaultLocation string Yes No Single Value plots only Plot LockLocation string Yes No Single Value plots only Plot AutoRows string Yes No Single Value plots only Plot Rows integer Single Value plots only Plot AutoCols string Yes No Single Value plots only Plot Cols integer Single Value plots only DDE Commands and Parameters Item Plot ShowChannel Topic instrument instrument Plot Scaled instrument Plot ChannelVisible instrument Plot UnitsVisible instrument Plot Item FontName instrument Plot Item FontStyle Plot Item FontSize Plot Item Color instrument instrument X Axis Settings Waveform Plots Topic Item Plot XAxisLabel Plot XAxisDefaultLabel Plot XAxisShowLabel Plot XAxisType Plot XAxisAction Plot XAxisAutoClear Plot X AxisChannel instrument instrument instrument instrument instrument instrument instrument Plot XAxisLocation Plot XAxisDefaultScale Plot X AxisMin Plot XAxisMax Plot X AxisFormat Plot XAxisSignifican
168. This closes the If PeakCount 3 condition statement 16 Close the Command equation table using the File menu Close command 17 Save the instrument with the button or select the File menu Save Instrument As command Save the instrument as STATE Display Page 1 of Eile Edit View Settings Start Layout Cursor Help AD vs Time Time Sec 2 11 11 97 10 39 00 AM Figure 13 9 Results of Subroutine and State Variable Tutorial When we Start this instrument it runs for almost two frames before it stops note the Frame number in the upper right corner Our first peak occurs with the first data point because channel AO starts at 5 volts which meets our peak condition of 4 5 volts The second peak occurs at the end of the first frame and spills over into the second frame The reason the next frame does not cause a new peak condition is because the value of CurrentPeak is still 1 Finally when the data goes above 4 5 volts towards the end of the second frame all of our conditions are met and the instrument stops Command Page 13 15 13 5 Tutorial Automatically Starting Another Instrument Building the Second Instrument This tutorial illustrates how to use the Command element to start another instrument based on certain criteria This method may be very useful in instances where you want to use one instrument for monitoring purposes and in th
169. UPC E 1 7 Standard Mode no edo eo eren ono ere m Pe EE eere PE E E a Ee 1 8 WildOWws 955 5 ihe ptatem anh ned E ee dre te e p d Rp AS ead is 1 8 Ma ndows NID ottenendo tea UN cuneate UA 1 8 Using Disk Compression or Caching Software eese neret 1 8 1 6 Start Using Snap Master cereis esee eese eee e teens esee sens esee es sese sns esee eess esee rosos sesse see eosseseesossecess LO Chapter 2 Snap Master Basics pA fdcjpigc E RS E Command Bar eei sessed wa ea ek SUR aha eh EE ITER EEA 2 1 Status B3E ettet teet tette etesee eter Neca ats ooh sse Roo eve its UN AOR ea 2 2 Toolbox ga EAE EEE EAS HER DERI REARBES CE E E 2 2 Instrument Wid OW ia entere eter eoe tergore eee tee e geo ve eee eere eren e eue egeo aap eee ee eges ey dette eee e decet 2 3 Comment Field tics ERIGI RIAM SOROUR RW RON RN WRIT 2 3 File Men eem tee ER to E te Rt atu s A e ors 2 4 Element Menu View Menu NinnpcM iE 2 6 Start Menua ete tinte eene ea emet vetet treo tu veste te orte vt ater e eot d MN exe ue ee ENT 2 9 Window Menirzuueadeatudeedauieeeec tnit tiae idee eiie HIN 2 9 ls M MC sess 2 9 Page ii Snap Master User s Manual PAIN 2 10 Overview of Blements ierit teet scusstedecdecies ccusetedecdscvesccessuededescdesccnstiededecdvesccescoeeds 2 10 Input Elements e EE Analysis Elements Output Elements Men
170. User s Guide Snap Master for FactorySuite Data Acquisition Module Waveform Analyzer Module Frequency Analyzer Module May 1998 Copyright 1991 1998 by HEM Data Corporation 17336 West Twelve Mile Road Southfield Michigan 48076 2123 U S A Voice 248 559 5607 Fax 248 559 8008 http www hemdata com Table of Contents Page i Table of Contents Overview Chapter 1 Getting Started 1 1 Wl COMC eee cds coccsctscoccscsscsscssacctacessecsesssscschetssnveavssenebetisnctdbtacessdocsseashccasecssosessiseasestsdissscosvesctesessscsessseses Lol sample Instruments iisipin ete bite i Te pel lli tede Lea reip ede te bte i idt 1 1 1 2 Technical Support eee e ecce eese eee eee ee eee enne es esee sna esee een esses ense sees ens eso eso sesso seoseseesesseseesesseees 173 RESistratiOn s 5 t sd wk athena en og eae canes eeu 1 3 Customer SUppOrt x x iiti io per irte ipei dete uae ie Revo E E EE A evs 1 3 Where To Go For Help 5 e eee de e RO e CRI UE RAPERE Ete PER FER Lt rs 1 3 When You Call For Support 0 eee eroe e cett e ee Er E PUR SER Pe e ET eee Redes UHR pe 1 4 What Is Technical Support eee meer rem pe tu P REC UHR RE 1 4 Extended Support Progt ms 52 REIR eU Res eet ne eee Maio 1 5 1 3 System Requirements 1 4 Installing Snap Master 1 5 Computer Configuration WNindows 3 15 5i mue ente itii iba mi eere metere 1 6 396 Brhanced Modeen eco CP t PRA PORE HARE RA REDE
171. X Values C Inside Grid Y Values z C Right Margin Fana Number Select Color cmos e Figure 3 33 Y vs T Plot Settings 1 Double click in the center of the Y T plot located in the upper left corner of the Display window This opens the Plot Settings dialog for the Y T plot Notice that we can access the X Axis Settings the Y Axis Settings and the Channel Settings from this dialog This is the same dialog that appears when you select the Plot Settings button in the Display Layout dialog Let s change the title of the plot using this dialog Notice that we can also turn on the Legend and Frame Number in this dialog as well as change the colors and fonts for the different plot components Display Page 3 35 2 Turn off the Use Default check box to the right of the Title text box This allows us to enter out own text for the plot 3 In the Title field type Channel AO From A D Demo 4 Press the OK button The title for the Y T plot should now be changed to our new title Now let s turn on all of the values on the X Axis of the Y X plot X Axis Settings Label Voltage Volts I Show Label V Use Default r Scale r Major Divisions Type Linear Major Divisions 5 l C Logarithmic Show As Vertical Grid T XPT Location Y 0 j M Auto Clear Sl Iv Show Axis Values manos C Minimum and Maximum Iv Default Scale All Major Divisions Minimum 10 Volts Maxi
172. Y Axis Calculation Output Bins C Sum Values Of All Bin Events CBinWidh 2 Vole C Average Values Of Al Bin Events of Bins po Count Bin Events Minimum 10 Volts Threshold 5 Volts Maximum o Volts Lox ce me Figure 15 29 Histogram Settings 5 Set the Input Channel to AO The A D Demo outputs time based data so make sure the Time radio button is selected then select channel AO from the Channel list 6 Set the Calculation to Count Bin Events with a Threshold of 5 Traditional histograms count the number of data points within a certain range so we must specify the Count calculation Because the A D Demo element has an output of 5 Volts set the Threshold to 5 Volts and the minimum and maximum In and Output bins to and 5 volts 7 Press the OK button to close the Histogram Settings dialog 8 Open the Display window then open the Display Layout with the Layout menu Display Layout ej B 6B M Insert Delete Plot Settings Channel Settings Page Settings Figure 15 30 Display Layout Depending on how you have Auto Layout configured you may need to delete the plots for channels A1 A2 and A3 Highlight the plots you do not need then press the Delete button ke Notice that the Plot Type for channel BO the output of Histogram element defaults to Histogram If you try to change the Plot Type a
173. Y T plot for channel AO a Y T plot for channel DO and a Mag vs F plot for channel MO In addition the X Axis for channel MO is set to display from 0 to 5 and the Y Axis is set to display from 0 to 5 The results indicate a power component at 0 5 Hz and zero power in the rest of the spectrum How do we interpret this information Page 14 34 Snap Master User s Manual The result of the Cross Power Spectrum function determines the average amount of power common to both signals If perform a Forward FFT of channel DO you would see frequency components from just past 0 Hz the DC Component all the way to 32 Hz the maximum frequency computed by the FFT in this case This means that the input DO has power at 0 5 Hz where the output AO also has power Because the output A0 has no power elsewhere in the frequency spectrum the remainder of the Cross Power Spectrum is zero 14 8 Tutorial Transfer and Coherence Functions The Transfer and Coherence functions are often calculated together using the Coherence function to indicate the validity of the Transfer function FFT Untitled Of x File Edit View Settings Builder Help gj c E mde amp NO Result Function Ch1 Ch2 Window Window Window Starting DC s Ch Type Width Overla Frames Avg Partial Frame Point Diop Figure 14 22 FFT Settings for
174. able or using the Equation Builder As in Snap Master s other tables the settings for each column are contained in the drop down list in the upper left corner of the table The first step for creating a new FFT equation using the equation table is to create a new result channel by entering a channel number using the element letter and channel number convention in the Result Ch column Note that the result element letter must not be used by any other Snap Master elements Default values are entered in the table for all other settings except the Ch1 and Ch2 columns which you must fill in using the drop down list Page 14 2 Snap Master User s Manual The following columns are listed in the equation table Result Ch Function Ch 1 Ch 2 Window Type Window Width Window Overlap Starting Point DC Avg Frames Avg Partial Frame Line number for the equation The result channel for the frequency domain equation Each result channel contains an element letter and channel number such as TO The element letter must contain only frequency domain data and each element letter can use only one frequency domain function When creating a new equation in the table specify the Result Ch first Specifies the frequency domain function to be performed Specifies the main channel for the function For functions operating on two channels specifies the second channel If only one channel is used this column is not neede
175. activity One of three methods for transferring data acquisition measurements to the computer s memory the other methods being DMA and polling The process of transferring data from or to a computer system including communications channels operator interface or data acquisition and control channels The adherence of a device s response to a straight line relationship Presents all available options or components Some lists allow for the selection of multiple items Lists are represented by a field and a pull down arrow Token used in the RS 232 element to define a special string of characters that must match the incoming string from the RS 232 equipment If the string tokens do not match an error is logged and the RS 232 element stops Companion processor to the microprocessor Contains hard coded programs to carry out fast and highly precise floating point operations along with mathematical functions A coprocessor is recommended for Snap Master to speed processing time Button located in the upper right corner of the window When the button is an up arrow clicking on it expands the window to the full screen size When the button is a double arrow the window is already maximized and clicking on it will return the window to its previous size and location Electronic devices that enable a computer to store and recall information In its broadest sense memory refers to any hardware capable of serving that end e g disk tape or semi co
176. adversely affect the outcome by adding artificial data The Ignore option ignore the extra points when the last FFT window does not a complete set of time domain data Noise Floor None C 12 bit 72 dB C 16 bit 96 dB Custom 100 B CENTS Figure 14 3 Noise Floor Settings The Noise Floor settings gives you an easy way to clean up the output of the FFT element by specifying the dynamic range of your signals When None is selected the raw output of the FFT results are presented to elements downstream The 12 bit 72 dB 16 bit 96 dB and Custom settings have an associated noise floor specified in decibels Any signal whose magnitude is below the noise floor setting has both its magnitude and phase set to 0 Page 14 6 14 2 Functions Summary Snap Master User s Manual The following reference list shows the functions available in the FFT element grouped by engineering discipline The Function column determines the frequency domain operation performed on the channels listed in the Ch1 and Ch2 columns For functions that operate on two channels the two channels being analyzed must have the same frame characteristics sample rate number of points per frame and frame duration Snap Master will not allow you to select channels for these functions that do not have the same characteristics General Function Forward FFT Inverse FFT Auto Power Spectrum Auto Power Spectral Density Cross Power Spectrum Cross Power
177. age Expanded Memory Expansion Board Exponential Extended Memory Extension External Box In External Box Out Fast Fourier Transform Snap Master User s Manual The DMA channel used by the data acquisition board must not conflict with DOS operations or any other devices in your system Disk Operating System Also refers to the command line based interface of PC compatible machines To drag an item click on it and hold down the mouse button While holding the mouse button down move the mouse until the item is at the desired location on the screen Release the mouse button A software routine that translates data to the format required by a particular device An internal Windows method to exchange information between different applications running simultaneously The ratio of the full scale range FSR of a data converter to the smallest difference it can resolve Dynamic Range DR 2n n is the resolution in bits Refers to a specific function or piece of hardware Elements have an associated icon and are located in the Toolbox For example the Display element represents the computer monitor where data can be viewed by the user Identifying letter given to each element when it is placed in the instrument Used with channels Messages that indicate violations of proper operating procedures Memory outside of the normal PC computer memory area May be referred to as bank switched memory This memory type conforms
178. ajea eae Sa lS 2 Al Channel Active Factor Offset Min Max Label Units ee 17 i 1 000 0 000 Di B5535 A0 iCount Figure 9 4 A D Settings 2 Press the button or select the Settings menu Frame Settings command Frame Settings Pacing Frame Length gt gt Type Hardware x C Duration o Sec Location C Intemal External of Points 2000 C Continuous X Axis Label Time Canal Help Figure 9 5 Frame Settings f Stop After 1 frames Sample Rate fi 00 4 Sec E of Frames m 3 Select the Hardware pacing type If your hardware device does not support Hardware pacing use Software pacing and set the Sample Rate in the next step to 10 4 Set the Sample Rate to 100 5 Change the Number of Frames to Stop After 1 frame The default selection for the Number of Frames group is for the instrument to run Continuously Select the Stop After radio button The default value for the Stop After field is 1 which is the setting we want 6 Press the OK button to close the Frame Settings Page 9 8 Snap Master User s Manual 7 Make sure the first channel has a Yes in the Active column 8 Press the 4u button or select the Device menu Hardware Configuration command 9 Press the 9513 Setup button 9513 Setup C
179. al C of Points oo Sample Rate i 27Sec Number of Frames Pacing Units Sec z C Continuous X Axis Label Time C Stop After frames m Figure 8 3 Frame Settings The Frame Settings dialog is used to set up the pacing clock source sample rate frame duration and number of frames for the device Pacing Type Location Software pacing relies on the computer s timer to determine when to acquire a new data point which is limited to a resolution of around 18mS or approximately 55 Hz Snap Master then duplicates measured samples to produce data at the specified Sample Rate Hardware pacing uses the clock specified by the Location which precisely controls the timing of each A D conversion With Hardware pacing the timing between samples is guaranteed The different types of Hardware pacing include IRQ interrupt based DMA direct memory access FIFO on board memory and REP INS repeat input string These are listed in ascending order of throughput DMA is faster than IRQ etc If the Type control does not appear hardware pacing is used Specifies if the pacing clock for the A D hardware Internal uses the timing device on the A D hardware When you specify an External clock you must supply the hardware with a TTL pulse train signal to determine when a sample is acquired Using an External signal for Pacing is also how asynchronous non linear time or without a time basis sampling is accomplished F
180. al The number of days between calibrations for the sensor The default interval is one day Inserting A Sensor Insert Sensor Sensor ID RTFM 421 Description r Scaling Kind T C x Eactor 1 Type J M Offset 0 Serial tt 102768 Input 3 Minimum 0 Model TCJ 001 Maximum 100 Manufacturer Omesa Engineering Units C x Max Input Freguency p Output 34 praon Minimum Interval 1000 zl days Magnum eo Last Cal Date 11 7 10 7 97 mm dd yy Units Was Cancel Help Figure 7 5 Insert Sensor Dialog Box To add a new sensor to the database press the Insert New Sensor button be The key piece of information for any sensor is the Sensor ID so you MUST enter a unique ID from all of the other IDs in your Sensor Database The Serial Model Kind Type Manufacturer and Max Input Frequency is provided solely for informational purposes and does not affect the scaling function This information is useful for keeping track of the identity of specific sensors when you need to order additional items Depending on the selection in the Automatically Calculate group in the Sensor Specifications dialog box one of the Scaling Input and Output groups is disabled This is to prevent you from inadvertently editing a value that Snap Master will calculate for you An alternative way to add a sensor to the database is to enter a new ID number for
181. al appears but it is not what you expected make sure you have the proper signal connection to the hardware If the Status Log appears with an ERROR entry follow the remedy listed If all else fails verify the hardware Configuration and your A D Settings Display Page 1 _ ol x Fie Edit View Settings Start Layout Cursor Help 2 J 3 Ha E ef ede eye e Voltage vs Time Frame IVAVAVAV AY Voltage Volts 10 0 5 11 10 97 4 08 05 PM Time Sec Figure 8 14 Acquiring a 1Hz 5 V Sine Wave 8 5 Tutorial Using Triggers to Start Acquisition Setting Up A Trigger Using triggers Snap Master can define when to begin acquiring a frame of data An example of this is using an input analog channel to define the starting point for data acquisition If your Trigger dialog does not look like the one shown in Figure 8 15 try to follow along we will not set up a complicated trigger in this tutorial 1 Open the A D Settings by double clicking on the A D Board element icon 2 Press the button or select the Settings menu Trigger command If the Trigger command is grayed out then your A D Board does not support any triggering in Snap Master In this case you can skip ahead to the next tutorial Page 8 16 Running the Instrument Snap Master User s Manual Trigger Settings r Trigger Mode ___ Trigger Condition St
182. ame function as Mode G except that the count begins after the Gate condition is satisfied After the second T C the counter waits to be rearmed and a Gate edge occurs to begin counting This differs from Mode H where the Gate is used to stop and start the counter Variable Duty Cycle Rate Generator with No Hardware Gating Output Only At the beginning of each frame the Load register sets the initial value of the counter then begins counting The counter accumulates until it reaches the first T C when it reloads the counter with the Hold register value Counting then proceeds to the second T C when the Load register value is used to reset the counter value The counting repeats in this fashion until a new frame when the counter value is reset by the Load register By setting the Output to the T C Toggled signal the Load and Hold values determine the output duty cycle A high frequency clock on the Source gives high resolution Variable Duty Cycle Rate Generator with Level Gating Output Only This mode performs the same function as Mode J except that counting only occurs on each Source edge where the Gate condition is satisfied This allows the Gate input to modulate the duty cycle because it affects both the High and Low portions of the output waveform Variable Duty Cycle Rate Generator with Level Gating Output Only This mode performs the same function as Mode J except that counting begins after the Gate condition is satisfied The c
183. ample rate These characteristics are determined on a per element basis In other words all channels that share an element letter have the same frame characteristics Also all elements that create any data such as A D Wave Generator Analysis etc must have frame characteristics associated with the element At the end of each frame every element reinitializes itself As a result there is an indeterminate amount of time between data frames Frames are designed for unattended captures of the same type of data such as using a trigger to capture 5 seconds after a particular event occurs If you are trying to acquire continuous data you can set up a long frame up to 2 147 483 647 points so there are no gaps in the data The usage of these frame characteristics becomes important when using the Analysis element to perform calculations using multiple element letters Please refer to the Analysis chapter for more information on how frame characteristics are determined for different equation sets 2 4 Tutorial Creating Your First Instrument This tutorial illustrates the basic tasks for creating an instrument in Snap Master We will create a simple instrument consisting of the A D Demo and a Display these elements are used in most of the tutorials The descriptions given in this section are extremely detailed which is provided for newcomers to the Windows environment Later tutorials contain less detail in regard to the general user inter
184. and return to the Equation Builder 16 Press the OK button to close the Equation Builder 17 Position the selection box in the second row Comments column Using the keyboard type Block Average then press ENTER Snap Master User s Manual Page 12 34 18 Position the selection box in the second row Label column Using the keyboard type Block Avg then press ENTER 19 Position the selection box in the second row Units column Using the keyboard type Volts then press ENTER 20 Switch to the main Snap Master window and save the instrument using the button or the File menu Save Instrument command Running The E Display Page 2 BE Instrument Block Avg vs Time L Time Sec 0 Time Sec Figure 12 19 Display Window with Input and Block Average Result When you run the instrument you should see the results shown in Figure 12 19 This Display window shows two Y T plots one for AO and one for PO 12 6 Tutorial Finding When An Event Occurs There are many instances when it is important to find out not only what the value of an event is but also when the event occurred The Find function produces either the point number or the frame time of an event Bui Iding The Analysis Untitled BE Fie Edit View Settings Builder Help Equation Eje amp amp RF e 7 ion
185. and software for proper data acquisition Please refer to the hardware documentation for information on its features and its use with Snap Master The Digital In Settings table or dialog operates in the same fashion as the A D element Pacing Frame Length Number of Frames and the Channel List have the same meaning for the Digital In as the A D element The main difference between the elements is the type of data acquired with the Digital In element acquiring digital data For more information on the digital input capabilities of your hardware please refer to the hardware s documentation 8 4 Tutorial Acquiring Analog Data Building the Instrument Before beginning this tutorial please make sure that your hardware and software are correctly configured The pictures shown in this example used a 5 V 1 Hz sine wave connected to Channel 0 of the A D configured as Device 1 If you use a different input signal you may see different results than those shown here For simplicity it is best to use a known signal as the input for this tutorial A D 4 4 D Board B Display Figure 8 11 Instrument for Analog Acquisition Tutorial 1 Create a new instrument with the button or select the File menu New Instrument command in the Snap Master workspace 2 Place an A D element and a Display element in the instrument Because you own the Data Acquisition Module you must select which A D element you wish to use When you click once on the A D e
186. andard Custom Settings E 2 C Hardware Dependent Condition ove en Type Analog Software x C iLevel One R Volts Channet A0 E orara 0 Volts I Exclusive Trigger Specify As A D Units C Sensor Units Pre Triggering Complex Triggers Pre Triggering ners T Multiple Stage Triggers Insert ij Specify As C Points C Seconds eet _v 2 Frame Length Delete Down Cancel Help Figure 8 15 A D Triggers Dialog Box 3 Select the Standard Mode Analog Software Type The default setting for the Trigger Type is Free Running which means that the instrument will run without requiring any triggers When you select Analog Software from the list the other groups in the dialog are activated 4 Select the Above Condition and specify a Level One value of 2 Volts This setting means that after the instrument is started the A D element waits for channel 0 to go above 2 volts No data will appear in the Display until after the trigger condition is satisfied Once channel 0 goes above 2 volts the full 5 second acquisition frame is acquired and displayed 5 Press the OK button to accept the changes to the Triggers dialog box 6 Close the A D Settings window with the File menu Close command 7 Save the instrument with the button or select the File menu Save Instrument command Press the button or the Start menu command When you run the instrument this time you will see the Displa
187. ange Syntax block tPoints Q verlap argumentt Description Separates argument into sections of length t Points with optional Overlap and performs the contents of argument for each section The last point in the each section is the output of the Block function lt lt Previous Tine Cancel Help Next Line Figure 12 31 Equation Builder with Block Average Function Definition 4 Press the button to insert the keyword in the Equation edit control 5 Type blockavg input in the Equation edit control 6 Click on the m button 7 Click on the Data Ranges item in the Category list then double click on the Block item in the Function list Analysis and Frequency Analysis Page 12 41 Calling The Function In An Equation Block Calculation block avin O w r Block Size Format Default Points Points Time Points 20 I Overlap E Syntax block Points D verlap argumentl Description Separates argument into sections of length Points with optional Overlap and performs the t contents of argument for each section The last point in the each section is output of the Block function pee Help Figure 12 32 Function Builder for Block 8 Press the button select the Statistical item Single Value item and Average item to open the Average Function Builder Average Single Value Calculation avg input ch ta Quick Functions 7 Syntax avglargument1 D
188. ange frequently write a user defined function to avoid any confusion about the precedence order of the equation To create a range integration function from the previous examples try the following function Define range_intg ch start stop intg range start stop ch Then you can call the function from the main body of the equation table for example RO range_intg AO 100 200 When using the Original syntax the range is specified directly after a function The format for using subranges is Channel function option first point last point If the function has no options then the option does not need to be included For example the equation SO A0a 100 500 calculates the average of channel AO between points 100 and 500 To integrate using Gear s 5th order method the equation would be RO AOi g 5 100 500 block points overlap arg1 Options p Frame Point Number t Frame Time Examples RO block 5 A0 RO block 10 2 A0 RO block t 1 A0 The Block function decimates the contents of arg by producing the last point in each block of length points If arg contains a function such as avg or intg the argument of that function is decimated At the beginning of each new block any equations within arg1 are reset The optional overlap parameter allows you to perform Moving functions by using the same data in subsequent calculations Page 12 24 Snap Master User s Manual gt gt TEL
189. anging the function of the counter For users who are familiar with the 9513 the Mode radio button lets you select one of the modes as defined by the manufacturer Custom enables all settings in the Connections and Registers groups for complete control over how the 9513 When Custom is selected the counter output has units of Ticks The common Usages are as follows Usage Output Units Description Pacer Divides F1 F5 by initial count pulses out each time count Frequency One Shot Pulse Count decrements to 0 Not intended for input channel 9513 Mode D Hz Counts the channel s source pulses Holds count and restarts at initial count each time Gate pulses Use same pulse connected to INT input for Gate input If the input frequency is too large to measure the output of the counter is 0 9513 Mode O Generates a single pulse after channel is started delayed by initial count Not intended for input channel 9513 Mode A Ticks Counts channel s source continuously without reloading initial count 9513 Mode F Page 9 4 Period Sec Rate Gen Rate Gen Gated Connections Snap Master User s Manual Measures time duration of channel s gate input edges If no internal pacer connect Gate input to INT input Otherwise only one pulse will be measured per sample interval If the period is too long so a T C occurs before a Gate edge the output is 0 9513 Mode O Divides F1 F5 source by initial co
190. annels being analyzed must have the same frame characteristics The result units are the output units over the input units such as volts volt or psi Ib The Transfer function H is different from the Coherence function because it represents the response of the system instead of the ratio of inputs to outputs By definition when the output and input both equal 0 then the result is also O If the input is 0 and the output is non zero then the result is infinite which is defined as 1029 by Snap Master The mathematical description of the Transfer function is H ab where b the output is aa the channel listed in the Ch1 column a the input is the channel listed in the Ch2 column G is the Cross Power Spectral Density of a and b and G is the Auto Power Spectral Density of a Page 14 10 Compliance Impedance Dynamic Compressibility Bulk Modulus Admittance Dynamic Flexibility Snap Master User s Manual Compliance is a special transfer function used in both hydraulic and mechanical systems In order to use this function the two input channels must have the same frame characteristics For hydraulic systems the numerator Ch1 of the calculation is a signal measuring flow and the denominator Ch2 is a signal measuring pressure The result units are units for flow over the units for pressure such as gpm psi Compliance is the inverse of Impedance For mechanical systems the numerator Ch1 of the calculation
191. ansferred to the Hold register until T C is reached These Gate edges do not alter the counting function After reaching T C the counter is reloaded with the Load register value and counting begins on the next Source edge after the next Gate edge that satisfies the Gate condition RS 232 10 1 RS 232 Settings Page 10 1 Chapter 10 RS 232 10 2 Tutorial Writing Example RS 232 Strings sscsssccssscssscesssscsseessscssssssssssessssenssecsesecsssessssssesessonssscssseensssees 10 8 e Answers To Commonly Asked Questions The RS 232 element provides an interface between Snap Master and external equipment that communicates ASCII data over the serial ports of your computer The communication can be either one way where Snap Master only reads incoming information from the equipment or two way so Snap Master can send ASCII commands to set up the equipment Like the other acquisition element dialogs such as the A D element the RS 232 element contains information about the equipment being controlled by Snap Master The Strings dialog contains information about how Snap Master interprets the ASCII strings sent by the equipment along with any strings used by the equipment for configuration These dialogs do not determine how the equipment actually operates they only specify how Snap Master communicates with the equipment e How fast does the RS 232 element sample data The rate at which the RS 232 element can read data is
192. ap Master is to accurately write the data to disk the Display may not plot continuously If you are interested in speeding up the performance of the plotting try using the different Plotting Techniques If you run the instrument a second time the File Exists dialog box appears This is because the file C SM DEFUSER TEST DAT already exists so Snap Master is making sure you do not want to overwrite the file To inhibit the File Exists dialog select the Auto Overwrite check box in the Disk Out Settings dialog box Page 4 14 Snap Master User s Manual 4 5 Tutorial Reading Data From Disk Building the Instrument A em A Disk In B Display Figure 4 16 Instrument for Disk In Tutorial 1 Create a new instrument with the command in the Snap Master workspace button or select the File menu New Instrument 2 Place the Disk In and Display elements in the instrument 3 Activate Pipe Mode with the button or select the Element menu Pipe Mode command 4 Connect the Disk In element to the Display element 5 Turn off Pipe Mode with the button or select the Element menu Pipe Mode command 6 Save the instrument with the button or select the File menu Save Instrument As command Save the instrument as DISKIN Specifying The 1 Open the Disk In Settings by double clicking on the element Data File Name Disk In Settings test dat c sm defuser batch000 dat Cy c Cancel batch001 dat batch002 dat I sm
193. are elements When Windows is running in 386 Enhanced Mode Snap Master uses a VxD Virtual Device Driver which is installed automatically with Snap Master to allocate a block of memory for DMA To set the amount of memory allocated for DMA data transfer select the Options menu then the Global Settings command Change the setting for of DMA Boards to the maximum number of DMA based I O hardware devices you will be using simultaneously You must restart Windows to have your changes take effect Page 1 8 Standard Mode Windows 95 Windows NT Using Disk Compression or Caching Software Snap Master User s Manual If you are running Windows 3 10 in Standard Mode you must run the SMSTART program to allocate memory for DMA based data acquisition hardware before running Windows The instructions for using the SMSTART program are as follows e Ifyou are currently running Windows exit Windows DO NOT use the DOS shell within Windows to run the SMSTART program e Change to the SM directory where the Snap Master program resides e Type smstart x win s Press ENTER This command runs the Snap Master support program and runs Windows in Standard mode If Windows does not start try typing the complete path name of your Windows files before the win command for example smstart x c windows win s If you include this command in your AUTOEXEC BAT file the SMSTART program is executed and Windows runs in Standard mode each time you s
194. as follows Condition Levels Description Above 1 Trigger occurs when the channel data is above Level One Below 1 Trigger occurs when the channel data is below Level One Inside 2 Trigger occurs when the channel data is between Level One and Level Two Outside 2 Trigger occurs when the channel data is outside both Level One and Level Two Positive Slope 1 When Level One is selected the Trigger occurs when the previous channel data point is below Level One and the current channel data point is above Level One 2 When Level Two is selected the Trigger occurs when the previous channel data point is below Level One and the current data point is above Level Two Negative Slope 1 When Level One is selected the Trigger occurs when the previous channel data point is above Level One and the current channel data point is below Level One 2 When Level Two is selected the Trigger occurs when the previous channel data point is above Level One and the current data point is below Level Two Specifies the levels for the various trigger conditions Selects if the Level 1 and Level 2 values are specified in A D Units usually volts or Sensor Units if a sensor is assigned to the channel Page 8 8 Pre Triggering Pre Triggering Specify As Complex Triggers Snap Master User s Manual Trigger Event Pre Trigger Data Post Trigger Data Data Frame Figure 8 5 Pre Post Triggering When selected specifies the amount
195. asaa aei 5 3 Tutorial Creating A Sine Wave eesseesseesseesseesoeesoeesoessoeesoeesoesooesooesooesooesosesosesosesosesosesosesoeesoeeseeeseeeseeeseeee 5 4 Tutorial Using Multiple Stages eeeseseseesseesseesoeesoessoessoessoessoesooesooesooesosesosesosesosesosesosesosesosesosesoseseeeseeeeseee or Command Bar Chapter 5 Wave Generator Page 5 1 en 5 2 ens 5 9 e 5 10 5 13 The Wave Generator element provides an easy method of creating both fixed function and arbitrary waveforms By combining the fixed functions using the multiple stage feature a wide variety of arbitrary waveforms are available Data from the Wave Generator can be used for data analysis as well as data output a Wave Generator Untitled BEE File Edit View Settings Help Els js Sy lel lare TES 18pezold Wes Triangle Wes White Noise No SINE 11 10 97 1 30 48 PM Figure 5 1 Wave Generator The Command Bar buttons unique to the Wave Generator element are Button Description Insert a new stage to the current channel Appends a new stage to the current channel Deletes the current stage Sets the sample rate and frame length Sets the waveform parameters Sets the stage length for the current waveform GS E 0 n En Lis Page 5 2 Table Columns 5 1 Waveforms Snap Master User s Manual In the Wave
196. ata File Naming Conventions Page 4 3 When creating a Snap Master native data file using a DAT extension you are actually writing data to more than one file Each DAT file acts as a reference to a number of SM files with the same file prefix The SM files contain the actual data from the elements where the is replaced by the element letter A D A Sensor B Device 1 CIO DAS16 E Display F Disk Qut D Analysis C Device 1 AT MIO 15X Figure 4 1 Sample Data File Naming Instrument For example this instrument is writing data in Standard Binary format to a file named TESTDATA The first file that is created is TESTDATA DAT In addition for each element you are saving data from such as the B and C elements the files TESTDATA SMB and TESTDATA SMC are created TESTDATA SMB will contain the raw data from the A D Board marked element B and the raw data from element C is saved in TESTDATA SMC If the Analysis element is creating new data channels such as RO then a TESTDATA SMR file is created The generic file formats use the extension assigned by the format when writing the data file such as PLT or CSV In addition data from only one element letter can be stored in a generic file This is because it is possible for each element letter to have a different number of points to save so Snap Master imposes this restriction when creating data files with the Disk Out element Page 4 4 4 2 Disk In
197. ation in the remaining columns is automatically filled in by Snap Master When another application is used as the data source all parameter columns are editable The following columns are listed in the DDE In table Channel Active Topic Link Item Label Units Specifies the output channel number for the link Specifies if the data for the Channel is sent out of the DDE In element If the channel is active and the specified Link Item is not available this column contains N A in red text Specifies the data topic for the channel If Snap Master is the data server application then the topic is the file name of the Snap Master instrument specified in the DDE Conversation dialog If another application is being used then this cell is editable by either selecting the topic from the pull down list box when the Use List To Specify Topics check box in the DDE Conversation dialog is turned on or by typing the topic name Specifies the data link for the channel If Snap Master is the data server application then the drop down list contains all available channels from the instrument specified in the DDE Conversation dialog If another application is being used then this cell is editable by typing in the appropriate link or by performing a Paste Link command to this cell Data is usually presented as a Hot Link where the data is updated automatically by the client or DDE In element Specifies a long name for the channel
198. ation on the Edit menu Paste command found in most Windows programs Note Only Time or Frequency domain channels may be copied result channels from the Histogram and Conditional element are not currently supported Also the maximum length of the DDE Topic string which includes the full path and name of the instrument is 100 characters For each channel in Snap Master there are a number of items that can be sent over DDE The available information for each channel is listed in the Items list in the DDE Out dialog box The following items are available data Transfers the data from the channel Time domain data is sent separately as a text string Frequency domain data is sent as magnitude and phase separated by a comma The number of frequency domain data points sent over DDE is equal to half the Window Width setting xLabel Transfers the label of the X axis associated with the channel For example time based signals usually have an xLabel value of Time and frequency based signals have an xLabel of Frequency xUnits Transfers the units of the X axis associated with the channel For example time based signals usually have an xLabel value of Secs and frequency based signals have an xLabel of Hz Page 6 10 points rate frameNumber yLabel yUnits factor offset yMin yMax Snap Master User s Manual Transfers the number of points per data frame for the channel All channels with the same element le
199. ay element Strip Charts and Y X plots 1 Select the Layout command 2 Position the selection box in the second row Plot Type column 3 Select the Strip Chart item from the pull down list Here is another use for the pull down list in the upper left corner of the Settings table When you view the list this time it contains the different plot types instead of the available channels This is because the selection box is located in the Plot Type column and the list is context sensitive We will review how to use this list box again 4 Position the selection box in the third row Plot Type column 5 Change the plot type to Y vs X For the third plot we will try something a little different The Y vs X plot type plots the channels listed in the Display Settings table the dependent variables against the channel used as the basis for the X axis which is specified in the X Axis Settings the independent variable Since we only need to look at one channel here let s delete the first channel 6 Position the selection box in the third row Ch column From the pull down list of channels select None When you delete a channel from the plot the channels shift to the left to keep the row complete In this case channel A1 is now Chl Display Page 3 33 Display Layout ej B 6B M Insert Delete Plot Settings Channel Settings Page Settings Ei Al Page Linked Title On Plot Type Ch 1 a iNo AD iD iy
200. ay element and will replace the reference to BO in the Title of the plot 4 Close the Sensor Assignment window using the File menu Close Assignments command 5 Save the instrument with the button or select the File menu Save Instrument command Running The Before we start the instrument let s remove the other plots from the Display window Instrument 1 Double click on the Display element icon to open the Display window 2 Select the Layout command 3 Highlight the plots of B1 B2 and B3 then press the Delete button amp 4 Press the Close button Page 7 12 Snap Master User s Manual 5 Press the Start button O Display Page 1 Fie Edit View Settings Start Layout Cursor Help odoare b eee Alem e Source Ch vs Time 50 1o x Frame 2 Source Ch C Time Sec 2 Start the instrument 11 10 97 3 39 55 PM Figure 7 13 Plotting Data Scaled With the Sensor Database The plot is titled Sample Ch vs Time which reflects our Label assignment in the Sensor element In addition the data has been scaled and the engineering units applied If you use a cursor on this data you will see that even the Cursor Data window displays the data in engineering units with the Factor and Offset already applied 7 6 Tutorial Updating a Sensor s Calibration History Snap Master allows you to keep track of the calibrati
201. channel AO 14 7 Tutorial Cross Power Spectrum Adding The Second A D Demo The next tutorials use functions that operate on two channels For this we can either use a different channel from the same source or we can add a second input source The next section will add a second A D Demo to the instrument which we will configure to output a sawtooth waveform A D 47D Demo D amp D Demo Figure 14 17 Instrument with Two A D Demos 1 Place the second A D Demo element in the instrument 2 Activate Pipe Mode with the button or select the Element menu Pipe Mode command 3 Connect the second A D Demo element to the FFT element 4 Turn off Pipe Mode with the button or select the Element menu Pipe Mode command 5 Open the second A D Demo element by double clicking on the icon in the instrument window Page 14 32 Snap Master User s Manual A D Settings Pacng gt Channel List Type Software aA Location C Internal External Sample Rate po Sec Pacing Units Sec zl DO D1 D2 D3 KCD Wu Tragers Free Running Frame Lenth 4 h Input Ranges 10 to 10 Volts C Duration j Sec tt of Points 200 Memon standard Device r Number of Frames C Continuous SawTooth zl G Stop After IE frames Erann Status Messages INTE Figure 14 18 A D Settings for Second A D Demo 6 Change the Sample Rate to 50 7 Change the Numb
202. complete the Basic Tutorials before you attempt to employ these examples Once you have become comfortable with Snap Master this section can be used as a reference guide to conventional test systems and their equivalent in Snap Master A D RE i 1 A Analog In B Disk Out This instrument is representative of a system that will acquire real world data and store it to a disk An analog input signal is sampled by an A D with all sampling parameters specified and maintained by Snap Master and the data is stored to a file on a disk By using Snap Master s Fast Binary Data Format you can stream the data to disk at high sampling rates Page 1 2 Digital Storage Oscilloscope Strip Chart Recorder Y X Plotter Meter Waveform Generator Controller Monitoring and Diagnostics Waveform Analyzer Spectrum Analyzer Signal Analyzer Digital Filter PID Control Snap Master User s Manual A D n E D Analog In B Display C Disk Out This instrument is similar to the Data Acquisition System but in addition to sending the data to a disk it is also displayed on the computer monitor The difference between each of the instrument samples is how the Display element graphs the data The Digital Storage Oscilloscope emulates an oscilloscope by plotting from right to left against a stationary set of axes and using time as the X axis The Strip Chart Recorder is similar but both the axes and the data scroll continuously from right t
203. configure the ODBC drivers on the client For more information please refer to the documentation accompanying IndustrialSQL IndustrialSQL Page 16 3 Start Time and The Start Time and End Time controls allow you to set start and end dates for the data requested End Time To set a start date or end date 1 Click the Iz button at the right of the control 3 1997 10 00 00 A E 11 13 97 gt Su Mo Tu We Th Fr Sa 1 kt eh REI TANE 9 10 11 1213 14 15 16 17 18 19 20 21 22 24 25 26 27 28 29 Figure 16 4 Start and Stop Date Selection 2 Select a date from the calendar by clicking on it Use the E and w buttons to move forward or backward in the calendar 3 Select a time using the z arrows You must insert your cursor in the section of the time stamp that you want to control with the arrows Resolution The Resolution setting sets the time spacing in milliseconds for the data in the tags The Sample Rate is calculated for this element based on this setting The maximum resolution that can be selected is 1 millisecond As you request higher resolutions the data transfer takes longer to retrieve the data from the IndustrialSQL database Once the data has been sent to Snap Master new requests are not made until you restart the instrument Tree View The tree view is a graphical representation of the namespaces in the database Each object in the database is listed as an item in the tree view The tree view consists of two pa
204. ct the A D Demo element to the Digital Out element 5 Turn off Pipe Mode with the button or select the Element menu Pipe Mode command 6 Save the instrument with the button or select the File menu Save Instrument As command Save the instrument as DIGOUT Page 11 8 Snap Master User s Manual Configuring the 1 Open the Digital Out Settings by double clicking on the element Digital Out Element Digital Out Settings r Pacing Channel Assignments Type Software zl Location G intemal C External itl x Available Channels en ad Output Rate C Default z Output R ps C Manual oae amt Ranges r Device 5 Prefill uir Hizi Slot 1 CIO DAS16 330i zl Durat 5 sains aga I Status Messages C t of Points Conantin t iP ston DR Ena Figure 11 9 Digital Out Settings 2 Set the Input channel for Out Bit 0 to AO This assigns the data from channel AO the 0 5 Hz sine wave from the A D Demo to output channel 0 If your hardware does not have a bit 0 use bit 1 instead 3 Press the OK button to close the Digital Out Settings 4 Save the instrument with the button or select the File menu Save Instrument command Running the 1 Press the button or the Start menu command Instrument When the instrument runs you should see the LED turn on and off or the meter reads high and low values about 2 times every
205. ctor of sixteen or BCD divides each stage of the frequency divider by a factor of ten FOUT is a special pin output of the Counter Timer hardware When the FOUT Enabled check box is turned on select an available Source along with a Source Divider When the FOUT Enabled check box is turned off the output at the FOUT pins is TTL low Counter Timer Source Source Divider Counter Settings Counter Function Page 9 3 The available Source signals are the frequency dividers F1 through F5 and the Source and Gate inputs of the available counters Note that the current frequency of F1 through F5 depends on both the Prescaler selection as well as the Source Divider Each frequency divider s current frequency based on the Source Divider setting is displayed directly in the Source list so no further math is required A 4 bit number between 1 and 16 which subdivides the Source Selects the counter number being edited in the dialog Internal Pacer designates the channel as the counter used to generate the inputs based on the Sample rate Only one counter needs to be defined as an Internal Pacer Remember to connect the output of this counter to the INT IN pin and connect the Interrupt Enable to ground Several common uses are listed with the Usage radio button When a Usage type is selected predefined settings are filled in the Connections and Register groups Certain controls are also disabled to prevent you from drastically ch
206. ctually plotted on screen If you are not acquiring data at high speeds or plotting large numbers of data points you may not need to use the plotting enhancements The most important item to remember when using the plotting techniques is that they only affect the output on the screen all data is available to any elements that are after the Display element Cursors and markers also follow the original data This means that all of the original data remains intact regardless of the plotting technique used Plotting data on the computer monitor requires many calculations which is one of the reasons a math coprocessor is highly recommended and a Windows video accelerator card should be considered for demanding plotting applications Because the plotting techniques subsample the incoming data it is possible to create a visual aliasing effect Make sure that you plot enough data points to show an accurate representation of the signal For more information on aliasing refer to Appendix C The different plotting techniques are Mode Description All Points The most complete plotting technique which plots every data point While this approach is excellent for slow moving data with relatively few data points or for replaying data from disk it can tend to impede performance during acquisition when more points need to be plotted Skip Plots every nth point where the number of points skipped is specified in the Points field You can specify wheth
207. d Specifies the window type used in the calculation of the frequency domain function Specifies the number of points in each window used for the frequency domain calculation At the end of each window the FFT element outputs a new frame of data Specifies the number of data points from the previous window used for the beginning of the current window Specifies the starting point within a data frame where the function will begin processing The default starting point is point 0 or the beginning of the frame This feature is useful for comparing functions on two channels where the event does not begin on the same point Specifies if the DC Component the value of the spectral line at 0 Hz is kept Yes or not No Specifies if successive result frames are averaged The number of frames is set in the Frames Avg column Averaging helps lower the amount of noise in the result If the Avg is set to Yes specifies the number of result frames averaged Specifies if the final result frame uses Zero Extended data or is Dropped This setting is only used if the number of data points available for the final result frame does not exactly match the window width FFT 14 1 Menu Commands Builder Page 14 3 Please refer to Chapter 2 for a description of the common menu commands FFT Equation Builder Line 1 r Frequency Domain Calculation J Result Channel F1 Volts Category Function a
208. database we need to have the Sensor element in an instrument We do not need to connect the Sensor to anything right now so we can simply include the element in a clean instrument window 1 Open the Sensor Assignments window by double clicking on the Sensor element icon 2 Select the Settings menu Sensor Specifications command Sensor Specifications Es ibe E Insert New Sensor Edit Sensor Delete Sensor Calibration History 284 532 ID in Kind Type Maus sem rape Om E IE PEE 204 532 Flow Turbine MAX B307125 421000 0 001 AC 000613 775 iDisplacemtEncoder Encoder Products 000613886 0 088 0 000 36 AC 000613 775 Displacem Encoder Encoder Products 00061388 0 088 ACCOUI jBcceleraicPiezo d AR 5720 SENSOR Displacemi ptical mI AR 5721 SENSOR Displacemi ptical 1 000 Baldour Er i i i i 10 088 DAC EPS 35 17 B7F Displacem Opitical Dynamics Hesearct oodi EP EE Delphi Saginaw EP 3795 1740 000 17 culate C Input Range C Output Range Lee Figure 7 9 Sensor Specifications Dialog Box Dynamics E Displacemi Optica EP 2165 nin G EP 2755 ES 3 Select Factor Offset for the Automatic Calculation When you add a sensor to the database you need two sets of numbers The Automatically Calculate group tells the Sensor element which numbers you do not have If you try to edit the cells that Snap Mast
209. dependent upon many factors including the type of PC the baud rate the instrument and other factors Many times an experiment must be performed to determine the performance with specific hardware Rates of three samples per second per channel while acquiring 32 channels have been achieved with the IOtech Tempscan 1000 e Can I control more than one RS 232 instrument at the same time The RS 232 element supports up to four pieces of serial equipment operating simultaneously e Does the RS 232 element support RS 485 The RS 232 element can support RS 485 the same way RS 232 specific equipment is supported However Multi Drop is not currently supported e f my RS 232 instrument doesn t support handshaking do I have to use it The RS 232 element does not require software or hardware handshaking e My instrument supports termination but not delimiters How does the RS 232 element support this hardware Even if your instrument does not explicitly support delimiters Snap Master may be able to support it if there is some constant character in the data string that can be specified as a delimiter For example the following data string has the format of time date data without specific delimiters 8 15 21 1 1 93 1 3 Volts Page 10 2 Snap Master User s Manual The year 93 could be specified as a delimiter because it does not change from reading to reading The string will be broken into two parts 8 15 21 1 1 93 and 1 3 Volts th
210. ding commands and parameters from another application such as a custom front panel The DDE Out element is only required if you are sending information from Snap Master to another application Dynamic Data Exchange Page 6 9 DDE Out Settings DDE Items Channel Item a 1 xLabel 2 xUnits points 3 rate frameNumber Z Copy Link To Clipboard Block Mode Data Points Per Block 1 Points Cancel Help Figure 6 4 DDE Out Settings The DDE Out Settings dialog provides an easy method of creating DDE Links between Snap Master and other applications In addition the Block Mode allows you to send data in larger chunks to send data into multiple spreadsheet cells or to increase the throughput of Dynamic Data Exchange DDE Items To transfer data between Snap Master and another application we must create a DDE link For Snap Master this means creating a DDE link from the DDE Out Settings dialog box A DDE link with the DDE Out element consists of two pieces of information the Channel and the Item To create a link select both a Channel from the Channel list and an Item from the Item list then press the Copy Link to Clipboard button The proper DDE information is automatically copied by Snap Master to the Clipboard To complete the DDE link switch to the program you want to share information with and perform a Paste Link command The procedure for this operation varies between programs but it is usually a vari
211. ds at each k p g p 1 This means that the number of points advanced for each block is p 4 points If there is any data remaining at the end of the frame that does not complete a full interval the final interval is dropped Graphically the calculation looks like this p 5 pp qn m 2929 t Gp 24 1 35 _Gp 34 to p 34 1 Lo 4p 4q to Spad Analysis and Frequency Analysis Page 12 25 To illustrate the overlap let s look at the equation RO block 10 3 avg A0 where the frame length is 40 points The result channel RO contains 4 points the block size divided by the frame length of the argument of average and the values of RO are as follows At point RO equals 0 the average of points 0 9 of channel AO 1 the average of points 7 16 of channel AO 2 the average of points 14 23 of channel AO 3 the average of points 21 30 of channel AO 4 the average of points 28 37 of channel AO points 38 and 39 are dropped because the final interval is not complete Miscellaneous Functions Fraction Modulus Round Truncate Channel Information frac argl Example RO frac A0 The Fraction function returns the fractional portion for the current point of arg1 The frame characteristics for the function result are determined by argl argl mod arg2 Options o Oversampling u Undersampling Examples RO AO mod Al RO A0 mod o Al The Modulus function r
212. e Files 4 2 e erre ed ree HH eae tue Fer tai Ree Ie EET eT TE aS eb EREL eeu Input And Output Values And Units Sens r ASSIgnfretitss 2 RI ene neee n e ea a dah vel ntis estes n etch bere irs Table Colutinsa 55 ioo oC AU ER At SERE OR RAE DR BR eR ALB eo MACC Yas 7 2 Sensor Menu Commands Wiew Menu secte ee ne ovt ch d ORE RO EU E OE ges Set ngs Menu secum OS EUH aee tea Rie eats 7 3 Signal Conditioning c eeeeeeeeeeeeeee eene eere 7 4 Tutorial Adding A Sensor To The Sensor Database eeeeee esee etes ee eterne esee enn esee enseeeesoseee 7 8 Building the Instr ment trat ette tter dva vd he tra RR RE Fu OD RE Inserting A New Sensor M 7 5 Tutorial Using The Sensor Element eee ee eee ee e eee eese eee eene esee en esee ens esos enssseesesseseesssseeeesess 7 10 Building Th Instrumente inii nor Ferr E ERR e NUI P tdensdueadebe sup He RE PEPERIT e EAR Assigning a Sensor To An Input Channel Dna ainsi MEEEEEE 7 6 Tutorial Updating a Sensor s Calibration History e eeeee esee eee e e eerte eee eene ese eeesseeeesess 7 12 7 7 Tutorial Additional Sensor Database Hints Copying An Existing Sensor 5 o eee tuit tede ei uete plo tue eee tete rg itus Using The Sensor To Assign Channel Labels esee enne enne Chapter 8 Data Acquisition 8 1 Analog Input A D
213. e Instrument Specifying The Data File Name A D 4 4 D Demo B Display Snap Master User s Manual q C Disk Out Figure 4 13 Instrument for Disk Out Tutorial 1 Create a new instrument with the m button or select the File menu New Instrument command in the Snap Master workspace 2 Place the A D Demo Display and Disk Out elements in the instrument 3 Activate Pipe Mode with the button or select the Element menu Pipe Mode command 4 Connect the A D Demo element to the Display element and the Display element to the Disk Out element 5 Turn off Pipe Mode with the button or select the Element menu Pipe Mode command 6 Save the instrument with the button or select the File menu Save Instrument As command Save the instrument as DISKOUT 1 Open the A D Demo Settings by double clicking on the element A D Settings r Pacing Type Software aA Location Internal C External Sample Rate 100 Sec Pacing Units Sec zl X Axis Label Time E Frame Length C Duration Po Sec t of Points 200 r Number of Frames Trggers Free Running input Ranges 1 to 10 Volts C Continuous Stop After 1 frames Memory standard Device Sine z Configuration Status Messages om em t Figure 4 14 A D Demo Settings 2 Change the Number of Frames to Stop After 1 frame 3 Press the OK button to close the A D Demo Settings
214. e the Integration function shown in Figure 12 5 has a single argument and a list of options the different integration methods to choose from Once you are in a Function Builder you can nest calculations using the button When you press the function button a pop up list appears which contains the built in Analysis functions organized by category using the same Category list from the main Equation Builder Selecting a function from the function pop up opens an additional Function Builder for the new function When you press the OK button in the Function Builder the contents are passed back to the previous Function Builder until you reach the Equation Builder Analysis Settings Equation Format Analysis Table Format RO cos A0 Run All Equations except Comments One Active Equation using Macros C Result Gn Lett RO A c alpen Pyne Iv Show Comments Column Memory Optimization Calculation Speed Slower Faster Result Data Dts 200 points per channel Function Defaults Function PEETS 2 Default Option Undersample Multiplication Division Power m Cancel Help Figure 12 6 Analysis Settings Equation Syntax The Equation Format has two main choices either the Enhanced Syntax for example RO cos A0 or the Original Syntax the equivalent equation would be RO AOc In addition the Original Syntax can specify the result channel either on the Left or Right side of the eq
215. e 1 3 will be read out of the second token e Does Snap Master support multiport RS 232 cards Multiport cards are not currently supported e Can the RS 232 element read Hexadecimal or binary data No the RS 232 element can only read numbers letters and some control characters Only numbers integers or floating point numbers can be interpreted as data e In order to read data from my RS 232 equipment I first need to send one string then based on the response I need to send a second string to retrieve the data Can I do this The RS 232 element does not currently support conditional responses or sending commands based on previous responses 10 1 RS 232 Settings A COM1 TempScan Settings Pacing Channel List Type Software E Location isan ested Sample mewak Secs jn Pacing Units Secs zl a X Axis Label Time Frame Length Duration 30 Secs Strings C of Points 30 bee Configuration Number of Frames 4 Continuous Devicet TempScan gt C Stop After 1 frames suis HEU cnet __ Figure 10 1 RS 232 Settings The Settings dialog informs Snap Master how the external RS 232 equipment is sending data over the serial port and operates the same way the A D Settings dialog works These settings are used by Snap Master only and are not sent to the external equipment Pacing The main pacer for the external equipmen
216. e 4 17 UNITSS x List of strings specifying the engineering units for each channel in the CHAN array as specified by the Sensor element Each value is separated by a comma DEFAULT LABEL x List of integers which specifies the channel label A 1 means the label from CHAN is used and a 0 means the user defined label in CHANNEL LABELS is used Each value is separated by a comma CHANNEL LABEL x List of strings of the user defined labels for each channel in the CHAN array Each value is separated by a comma CHANNEL TYPESS x List of strings specifying the type of channel for each channel in the CHAN array Each value is separated by a comma For time data the channel type is yt For frequency data the channel type is yfp p is for polar frequency format data CHANNEL RANGES x Numerical range of values specifying the upper and lower limits of the data for each channel in the CHAN array The values are usually determined by either the Sensor element or the Input Range of an input element The range is enclosed in parentheses and separated by a comma for example 10 10 Each channel is also separated by a comma FFT BLOCKSIZE x Integer specifying the interleave size for amplitude and phase data If no frequency data is in the file this value is 2048 If frequency data is in the file and the value is 1 then the magnitude value is followed immediately by the phase value CLUSTE
217. e File Name field already exists then Snap Master asks you if you want to overwrite the file or change the file name using the File Exists dialog box To inhibit the File Exists dialog turn on the Auto Overwrite check box to always overwrite an existing data file ASCIl File Export When you select an ASCII File Format such as a Comma Separated Variable or ASCII Plotter the ASCII File Export Group is activated These settings determine how Snap Master writes the data from the file Number Format Specifies the text format of the data in the file The Decimal format specifies an absolute number of digits for the numbers before and after the decimal and results in consistent columns for each data point Using the Scientific format produces numbers that always show the value in terms of an exponent of 10 Engineering units allows the user to set the precision of the data file by specifying the number of places after the decimal Save Time When selected the first channel of the data file contains the elapsed time Freq Channel from the instrument start of each data point If the check box is not turned on then there is no time or frequency channel included Disk Out Save Options Channel List Frame List Vs Iv Save All Frames co Frame it Add To List Delete From List Cancel Help Figure 4 8 Disk Out Save Options The Disk Out Save Options dialog specifies which channels and which frames to save to disk while the in
218. e Snap Master workspace button or select the File menu New Instrument 2 Place the Wave Generator Smoothing and Display elements in the instrument 3 Activate Pipe Mode with the button or select the Element menu Pipe Mode command 4 Connect the Wave Generator element to the Smoothing element and the Smoothing element to the Display element 5 Turn off Pipe Mode with the button or select the Element menu Pipe Mode command 6 Save the instrument with the button or select the File menu Save Instrument As command Save the instrument as SMOOTH Page 15 14 Configuring The Wave Generator uj Wave Generator Untitled File Edi View Settings Help Snap Master User s Manual EEE EE E pa E amp Yes Output Active Channel Waveform Stage Length Stage nel Channel Units Units C TT Figure 15 20 Wave Generator Settings 1 Open the Wave Generator Settings table 2 Activate the first channel by selecting the first row Active column and selecting Yes from the drop down list 3 Open the Frame Settings dialog by pressing the button in the Command Bar or selecting the Settings menu Frame Settings command Frame Settings Sample Rate 100 4 Sec Frame Length Duration 10 See C 4 of Points 1000 E points Number of Frames C Continuous Stop After fi Ej
219. e Type 3 Z Bath Temperature 0 C Electronic Factor cw e Offset f0 c Cancel Help Figure 15 9 Cold Junction Compensation Settings The CJC Cold Junction Compensation settings defines which channel is used as the reference point for all temperature calculations used by the TCLinear element The Units specifies the temperature units used to define the CJC calculations There are two types of support CJC Thermocouple or Electronic The Type of thermocouple is selected along with the current Bath Temperature of the thermocouple For an Electronic CJC enter the Factor along with corresponding scale and the Offset values 15 4 Tutorial Thermocouple Linearization Building the Instrument These tutorials shows how to linearize one thermocouple channel using the TCLinear element Instead of the A D Demo we use for most tutorials we will use the Wave Generator element to generate a very low level sine wave because the TCLinear element normally deals with signals on the millivolt level 5K C A Wave Generator B TCLinear C Display Figure 15 10 Instrument for TCLinear Tutorial 1 Create a new instrument with the g button or select the File menu New Instrument command in the Snap Master workspace 2 Place the Wave Generator TCLinear and Display elements in the instrument 3 Activate Pipe Mode with the button or select the Element menu Pipe Mode command 4 Connect the Wave Generator elemen
220. e Width Spectral Lines Side Lobe Height BSSR Bee SBS Best Case 1 0 dB 42 104 0 dB BSSR Bees BO Worst Case 642 skirted 13 5 dB The Rectangular window is actually equivalent to no windowing at all since all points within the window width are multiplied by 1 The response in the best case is excellent as documented in the examples at the beginning of this section The worst case response is not as good with an absolute attenuation of about 74 dB Riemann Frequency Response 60 dB Bandwidth Spectral Lines Main Lobe Width Spectral Lines Side Lobe Height 8 8 s5H5sSbs5s5 Best Case 26 116 85 0 dB BSSR Bees BO Worst Case 46 101 7 dB With much of the main lobe energy below 60 dB the Riemann window exhibits consistent wide bandwidth response to both cases The side lobes are negligible making this window more appropriate when the frequencies of interest do not fall directly on the spectral lines Page 14 24 Snap Master User s Manual Sine 3rd Power Best Case Worst Case Frequency Response BSSR Bee SBS BSSR Bees BO 60 dB Bandwidth 10 4 10 6 dB Spectral Lines Main Lobe Width 40 9 Spectral Lines Side Lobe Height 108 1 dB 111 4 dB Like the Half Cycle Sine window the Sine 3rd Power window has excellent response in the worst case with an impressive drop off below 60 dB In the best case the wide bandwidth response is adequate because the he
221. e are very good and much of the main lobe energy in the worst case is below 60 dB Cosine Tapered Frequency Response 60 dB Bandwidth Spectral Lines Main Lobe Width Spectral Lines Side Lobe Height Worst Case 18 49 4 dB 31 2 dB A ringing around the main lobe is a characteristic of cosine based windows The main lobe width for both cases is fairly narrow but the side lobes are well above 60 dB This makes the Cosine Tapered window sufficient for cases when the frequencies of interest are well known Exact Blackman Frequency Response 60 dB Bandwidth Spectral Lines Main Lobe Width Spectral Lines Side Lobe Height Worst Case 6 36 7 dB 68 2 dB The Exact Blackman window behaves like other windows sharing its namesake with a narrow main lobe width and a severe drop off below 60 dB The side lobe height in the worst case is not as low as the Blackman Harris window but this is another good window choice when the frequencies being measured fall on or between the spectral lines FFT Exponential Frequency Response 60 dB Bandwidth Spectral Lines Main Lobe Width Spectral Lines Side Lobe Height BSSR Bees BO Best Case 319 skirted 80 0 dB BSSR BBS SEO Page 14 19 Worst Case 695 skirted 73 3 dB The Exponential window has a skirted response for both the best and worst cases This window is a classic wide bandwidth window as evidenced by the
222. e computer If you do not use the Data Acquisition Module OR your acquisition hardware does not require DMA set the number to 0 If you change the number of boards you MUST restart Windows not just Snap Master for the change to take effect Instrument Settings Comments C None COneline ine p Background Select Color Select Picture Picture Location C Upper Left C Centered C Tiled Clear Picture Status Messages Cancel Help Figure 2 8 Instrument Settings The Instrument Settings dialog customizes the appearance of the instrument window Comment Field The Comment Field group determines the number of lines displayed in the Comment Field Any text stored in the Comment Field is retained regardless of the number of lines showing Background The Background settings allow you to specify a new background color or picture for the instrument window Finally the Status Messages check box determines if the Start and Stop instrument messages are sent to the Status Log Turning Status Messages off decreases the number of messages posted in the Status Log Snap Master Basics Status Bar Settings Start Menu Window Menu Cascade Tile Arrange Icons Help Menu Contents How To Use Help Snap Master Tutorial Page 2 9 Status Bar Settings Vs M Date and Time Status Bar Font OK Cancel Figure 2 9 Status Bar Settings Visible Check boxes specify if t
223. e devel sd 12 31 12 5 Tutorial Performing A Block A verage eeeee esee cete eese eene seen ense en esset ense set ts esee teas s ee tous 12 32 Building The Equation ss ss 22 30 1355 diet dede dett dee td der tede eed 12 32 R unmne The Instrut nt so i cedere etr ee pepe sang RH eerte evar re rte tes Pep ecu 12 34 12 6 Tutorial Finding When An Event Occurs e eeeeeeee esee esee eese n seen seta setenta tense enata sse tns seus 12 34 Building The Equati b i2 ine eset te eerte tete ee DPA eet pides 12 34 Running The Instrument tdi E i dede e ert deo derer a Ede dee nee Ped 12 36 Page viii Snap Master User s Manual 12 7 Tutorial Integrating Over A Specific Range Of Data c eeeeeeeeeeeeeeee eene eeneenneeneeeeeees 12 37 Building The Equation 6n entente eene em edet me ete e p ete 12 37 Running The Instrument nid bie E D e RR PUR EUR EHE 12 39 12 8 Tutorial Defining Your Own Functions eese eee ee eene eene eene tenes ens sess se snssesssseesseeessecesses 12 40 Defining A New Functioti icing dedere dere dere edere Pep es 12 40 Calling The Function In An Equation esses nere neret neret nnen nennen rennen ne 12 41 Running the Instrument 2 retinet ne eee ese e ERE nee TRE de eine dae eua qoa 12 42 Chapter 13 Command Command Bars cient endedndactite eredi E002 Fava cask tu Fees Gadd Debe Ao ta eared e done RE PEs 13 1
224. e directly on top of the waveform to place a cursor A new entry appears in the Cursor Data table for the cursor you placed If you are having trouble placing the cursor try retracing the data with the button then place the cursor lDisplay Page 1 Eile Edit View Settings Start Layout Cursor Help CE CH POLES ES C2 J eei ey 8 Marker Label Ch Linked Pt X Value Units Y Value Units Channel Label Type Slope ANT olki Pg Plot n ijS9ec i 599119iVolts Voltage Abs 0 000000 1 Channel Al m Channel A0 from A D Demo Frame 1 J a A0 Nolts e o Time Sec Al vs Time A Nol Time Sec Stopped instrument C SM DEFUSER EXAMPLE1 INS 11 10 97 11 47 15 AM Figure 3 40 Display With Cursor In Upper Plot Display Page 3 39 Moving The Cursor Once the cursor is placed you will usually want to move it to the location where you want to read the data value There are two ways to move the cursor 1 With the mouse pointer located over the upper plot press the right and left mouse buttons to move the cursor forward right mouse button and backward left mouse button in time When you press the mouse buttons the Skip Rate value is used to determine how many points to move By default the Skip Rate is 1 2 Move the
225. e ee pite ep eter de eee etie egere itg 13 12 Running The Instr ment nene et endete eter eo e ead al dbase 13 14 13 5 Tutorial Automatically Starting Another Instrument eee eeee eese eee een ee ee eene eee eeeseeeeeese 13 15 Building the Second Instrument eese Updating The Command Routine Running The Instr ment entere tn eter eese eere esee de ve eee Eee e P eee ed aee os s Chapter 14 FFT Command Bary uen eI Une DINER ROS IG n BAS 14 1 Tabl Colum ie ee eterno ete teer dete etre coe detestatur eee ertet ee e eee gue 14 1 14 1 Menu Commands i ccsescsensssecissssevssansisesicectevsennsssesiesctonnteesssevieessansteasssestetsdansseesssevtesstersssesssesteaseaste 14 3 Builders eee entes ute t tutte ute tette tu e tee 14 3 SUMMA e UM 14 6 Forward EET 63 ne aee ele eet tete te tert ite tee eto uite etae te ete eee te Et ene nd 14 7 Inverse BET aO ARETE ATS ANAL RAN MERE Ate et tat 14 7 Auto POWER Specifu estinse aneng eere ie e ever e eene dep e teneret dete dewey oun dee pede eate ede te ER 14 7 Auto Power Spectral Density 2 cde dere rbd doe ederet edo re Pee eL endo eva ro eec cie RE ed 14 7 Cross Power Spectr tu i set ete ete tete tee etn eee ter E eek saa Rte RE ere e eR e douse coed 14 8 Cross Power Spectral Density eese nennen nennen nenne a r e ara ee ener 14 8 Coh rence Punction e eget Er eei e p e Reiter Te rte epe rss 14 8 Coher
226. e eighth row type IncrementCount then press ENTER Because the statements have determined that the latest data point has just gone above the peak threshold we can now increment the value of PeakCount using the IncrementCount subroutine 9 In the ninth row type End If then press ENTER This ends the If CurrentPeak 0 statement 10 In the tenth row type Else then press ENTER With this Else statement we can process a set of statements when the value of channel AO is less than 4 5 volts 11 In the eleventh row type the equation CurrentPeak 0 then press ENTER When the value of channel AO is less than 4 5 volts we must set the value of CurrentPeak to 0 which corresponds to our definition of the CurrentPeak state variable 12 In the twelfth row type End If then press ENTER We have no more statements for the value of channel AO and the peak threshold so the End If terminates that condition statement Page 13 14 Snap Master User s Manual Running The Instrument 13 In the fourteenth row type f PeakCount 3 Then then press ENTER Now we have finally come to the point where we look at the value of the PeakCount state variable to determine if we have reached the maximum number of peaks 14 In the fifteenth row type Stop then press ENTER If the value of PeakCount has reached its maximum then we want to stop the instrument with the Stop action 15 In the sixteenth row type End If then press ENTER
227. e event of an error use another instrument to log data to disk We will add on to the previous exercise where in addition to stopping the instrument we will start another instrument 4 4 D Demo B Display C Disk Dut Figure 13 10 Instrument for Storing Data Based On A Condition 1 Create a new instrument with the button or select the File menu New Instrument command in the Snap Master workspace 2 Place the A D Demo Display and Disk Out elements in the instrument 3 Activate Pipe Mode with the button or select the Element menu Pipe Mode command 4 Connect the A D Demo element to the Display element and the Display element to the Disk Out element 5 Turn off Pipe Mode with the button or select the Element menu Pipe Mode command 6 Save the instrument with the button or select the File menu Save Instrument As command Save the instrument as CONSTORE INS Page 13 16 Snap Master User s Manual Updating The ee os Command Routine E a Equation Definition 4 Figure 13 11 Command Equations To Start Another Instrument 1 Move the selection box to row 16 and press the button 2 In row 16 type Start CONSTORE INS then press ENTER When you want to start another instrument using the Command element that instrument must already be loaded in the workspace 3 Switch back to the main Snap Master window a
228. e first A D element is still available to the Display and Disk Out elements 6 Turn off Pipe Mode with the button or select the Element menu Pipe Mode command 7 Save the instrument with the button or select the File menu Save Instrument As command Save the instrument as MULTBDS If you are using input elements other than two A D Boards then apply the setup procedures to your specific elements 1 Open the A D Settings dialog box for element A A Device 1 A2D Settings Untitled olx File Edit View Settings Device Help jeje ES als AO Channel 0 Figure 8 17 A D Settings 2 Press the button or select the Settings menu Frame Settings command Frame Settings Pacing Frame Length Type Hardware Duration s Sec Location Internal C External C t of Points 500 C Continuous X Axis Label Time Stop After fi frames Cancel Help Sample Rate 100 Sec E of Frames Figure 8 18 Frame Settings 3 Select the Hardware pacing type 4 Set the Sample Rate to 100 5 Change the Frame Length to a Duration of 5 seconds 6 Change the Number of Frames to Stop After 1 frame Data Acquisition Page 8 19 7 Press the OK button to close the Frame Settings 8 Make sure the first channel or the channel you have your input wired to has a Yes in the Active column 9 Close the A D Settings window with
229. e first row then select channel Yes from the list 5 Position the selection box in the Label column of the first row then enter Area 1 for the label We are not actually measuring any thermocouples in this exercise so you can select any Type you want the tutorial will use type J Utility Elements Page 15 11 Specifying The 1 Press the CJC Settings button CJC Settings Cold Junction Compensation Settings Cold Junction Compensation CJC C3 chamet Were z tome E zd Method Thermocouple Type 3 Bath Temperature 0 C Electronic Factor 1 Offset 0 t Cancel Help Figure 15 15 Cold Junction Compensation Settings 2 Select Electronic in the CJC Type group Because we do not have an actual CJC channel we will use an electronic CJC With a Factor of 1 and an Offset of 0 our source data will not be altered 3 Press the OK button to close the CJC Settings 4 Press the OK button to close the TCLinear dialog box Running the Instrument Display Page 1 File Edit View Settings Start Layout Cursor Help o tss asl Ol x Area 1 vs Time Frame Hl Time Sec WV EV Y Y Time Sec Figure 15 16 Results of TCLinear Tutorial When you run the instrument the original data is channel AO show
230. e most recent value of the pulse count on each interrupt In applications where you want highly accurate readings set the Special Gate to Enabled and connect the Pacing channel which we cover next to the Gate of the counter This way each Gate edge transfers the contents of the counter to the Hold Register and Snap Master reads the value Counter Timer Configuring A Counter As An Internal Pacer Signal Connections Page 9 9 9513 Setup r Configuration Connections 9513Chip i Source F1 1 MHz zl Prescaler Binary C BCD Count On Rising Edge Falling Edge FOUT Enabled Gate None E Source E Output r C Toggle z Source Divider E Registers 1 Counter Settings Load Register Hold Register Counter B M Count Down C Up Function Internal Pacer T C Reload Load Only C Load Hold C Usage c Cycte C Once Repeat CMode D Format Binary BED Custom Special Gate Disabled Enabled Cancel Help Figure 9 7 9513 Settings for Internal Pacer In order to read the values from Counter 1 we need a pacer to define when a hardware interrupt occurs For this tutorial we will use Counter 5 as an Internal Pacer 1 Select Counter 5 from the Counter list 2 Select the Internal Pacer radio button Once a counter is specified as an Internal Pacer no other settings need to be changed The value
231. e of the Carrier and Modulator sine waves DC Offset Specifies the offset from 0 volts for the resulting waveform Phase Specifies the phase shift of the resulting waveform Ramp Settings Stat At Hold Previous Value New Starting Value 0 Volts EndAt 5 Volts Cancel Help Figure 5 7 Ramp Settings The Ramp function produces a straight line waveform that changes at a constant rate from the Start At value to the End At value for the duration of the waveform stage The slope of the waveform is determined by the difference between the Start At and End At values and the duration of the waveform stage Hold Previous Value Uses the last data value from the previous stage for the Start At Value of the function New Constant Value Uses the specified value for the Start At value of the function End At Specifies the value of the last data point in the waveform stage Page 5 6 Sawtooth Sinc Snap Master User s Manual Sawtooth Settings Sawtooth Parameters Frequency a Hz Amplitude 10 Volts DC Offset volts Phase p Degrees ea es Figure 5 8 Sawtooth Settings The Sawtooth function produces a waveform which increases at a constant rate from its minimum value to its maximum value then resets to the minimum value Frequency Specifies the frequency of the sawtooth waveform Amplitude Specifies the peak to peak amplitude of the waveform DC Offset Specifies the offset from 0 volts for th
232. e of the Display window decreases 7 Press the OK button to accept the new settings Page 3 30 Deleting and Inserting Plots Snap Master User s Manual 8 Press the button Display Page 1 o gt Eile Edit View Settings Start Layout Cursor Help o missi AD vs Time 3 Time Sec Time Sec A2 vs Time A3 vs Time Time Sec 0 Time Sec Figure 3 27 Multiple Color and Line Thickness By now you may have noticed that not much happens in the plots of channels A2 and A3 One way to enlarge the plots for channels AO and A1 we can delete the bottom two plots from the Display Layout table 1 Select the Layout command in the Display window 2 Highlight the third and fourth rows in the table by clicking and dragging from line 3 to line 4 3 Press the Delete button ke The Confirm message box appears asking if you want to delete the selected plots This is a safety measure to ensure that you did not press the Delete button inadvertently 4 Press the Yes button in the Confirm message box 5 Press the Close button to close the Layout dialog Notice that the plots of AO and A1 have been enlarged to the maximum size within the Display window Only channels AO and A1 are now displayed This brings up an important concept not all channels of data need to be displayed when the instrument is running There i
233. e or clear the channel list Ch 1 Specifies the channels to be overplotted on the same axes Ch 2 Ch 16 Page 3 24 Insert Delete Plot Settings Channel Settings Page Settings Snap Master User s Manual Inserts a new table entry above the selected plot or plots Removes the selected plot or plots from the layout To alter the appearance of a specific plot position the selection box on the plot you wish to change and press the Plot Settings button The Plot Settings dialog that appears depends on the plot type of the row you selected To change the appearance of the channel colors and line styles press the Channel Settings button Display Page Settings 1 Page Default Title Auto Rows Auto Cols Title Rows Cols No Display AI Piot Types No nS Yes 1 les DiplarPage2 Yes Yes a Aves Display Page 3 Yes NEN CNN Yes Display Page 4 ED NN ies 1 ies Display Page 5 EE LLL ies Yes Display Page 6 Yes Yes Yes Display Page 7 Yes Yes Nes i Display Page 8 Yes i iYes Close Help Figure 3 21 Display Page Settings eoruni como z 2 The Display Page Settings dialog defines the window titles for each Display page and the number of rows and columns used for each page Column Page Default Title Title Auto Rows Rows Auto Cols Cols Description Specifies the Display Page for these settings Define
234. e reaches 0 The T C is used to reload the initial counter value or to control other counters A temperature sensor created by joining two dissimilar metals The junction produces a small voltage as a function of the temperature The maximum repetitive rate at which a data conversion system can operate with a specified accuracy It is determined by summing the various times required for each part of the system and then by taking the inverse of this time Used by the RS 232 instrument to represent information in a string sent by a piece of RS 232 equipment Available token types include Literal Match Place Holder and Channel Data Glossary Toolbox Transducer Transfer Rate Trigger Unipolar Waveform Analyzer Module Window Workspace Page A 9 The Toolbox is located on the left side of the workspace All available element icons are placed in the instrument by dragging the icon from the Toolbox and dropping it in the Instrument window Converts an input electrical or non electrical to an electrical output examples are a strain gauge or thermocouple The rate measured in bytes sec at which data is moved from source to destination after software initialization and set up operations the maximum rate at which the hardware can operate Pulse or signal that is used to start or stop a particular action Triggers are frequently used to control data acquisition processes A signal range that is always positive for examp
235. e refer to Chapter 2 for a description of the common menu commands Add a new stage in the current channel before the current stage Delete the current stage Add a new stage in the current channel after the current stage Frame Settings Sample Rate 1000 Sec r Frame Length Duration 5 Sec C of Points 5000 E points Number of Frames C Continuous c Sm After n B ES Cancel Hei Figure 5 14 Frame Settings The Frame Settings dialog determines the frame characteristics of all channels in this Wave Generator element Sample Rate The Sample Rate defines how many times per second the Wave Generator element generates a value for each channel The X axis units are always defined in Seconds and the X Axis Label defined as Time A high sample rate for the Wave Generator produces high resolution data internally in Snap Master but this does not make the output hardware run any faster If you are outputting data generated by the Wave Generator using D A or Digital Out hardware the output rate of the hardware element determines the final resolution of the data Frame Length Defines the size of each data frame At each frame boundary the Wave Generator element resets and restarts the waveforms from the beginning Number of Frames The Number of Frames group allows you to specify how the element operates in the instrument When the Continuous option is selected the instrument will continuousl
236. e resulting waveform Phase Specifies the phase shift of the resulting waveform Sinc Settings Sinc Parameters Frequency a Hz Amplitude 10 Volts DC Offset 0 vols Phase fe Degrees PeakAt Start End comet ne Figure 5 9 Sinc Settings The Sinc function produces a waveform which is defined as one at time equals zero scaled by the amplitude and is equal to sinx x for the remainder the beginning of each cycle increases at a constant rate from its minimum value to its maximum value then resets to the minimum value Frequency Specifies the frequency of the sine wave portion of the waveform Amplitude Specifies the peak to peak amplitude of the sine wave portion of the waveform DC Offset Specifies the offset from 0 volts for the resulting waveform Phase Specifies the phase shift of the resulting waveform Peak At Specifies if the sinc function is at its maximum relative time equals zero at the Start or the End of the cycle Wave Generator Page 5 7 Square Settings Sq u a re r Square Parameters Frequency 1 Hz Amplitude 9 Volts DC Offset 0 Volts Phase o Degrees Duty Cycle po x ea des Figure 5 10 Square Settings The Square function produces a waveform which oscillates between its minimum and maximum values The oscillation occurs at the specified frequency with the Duty Cycle determining the amount of time the function is at its maximum value within one cycle Frequenc
237. e tret 15 11 15 5 Smoothing 1 ecce eee esee eese eese eene seen esses ene sees ens esee nosse sense see senss sees ense so sossesessseseesesseseeseses 12 7 12 Tabl Columtiis 23 erede ie a see dia ae ie eri Ter ier 15 12 Sinootl ngOptIOIs 2 0 ettet et ete eate tet rte ice tenete tite ete e etes tees 15 13 15 6 Tutorial Smoothing eee eee eee eee eee ee ee eene tense tense tense ense esos se soss esses eessse esse sssesesseesseees 127 13 Building the Instr ment 5 5 onere e eet eret deed iere bed ents e eet pe ee aene 15 13 Configuring The Wave Generator eeesseeseeeeeeneeeeeen nennen enne TENE en neret TN h 15 14 Configuring The Smoothing Element eese eene nennen neret neen nenne nnene nennen 15 15 Specitying The Rise Time oni deep e da ie pe dee baden dee tacet 15 16 Running the Instr merit 5er ei re Pp eg E ret Eu ii ett dee dose hate diee eg gs 15 16 15 7 Iinrici EC 9 E IA HistoBratn uoce Ne tenete tete e t Ote ute dat o ten detestatur M hc 15 18 Band Analysis aieo SH a ER RECHERCHER EE Oe HD 15 18 Octave Band Analysis ie eee pe ee eee deeem 15 18 15 8 Tutorial Histogram censu eee ee ee ee eee ense etes e sees ense see sns sse eenss sees enses ee sesse so ssnsseeeseoseseesssseseeses 15 19 Bildin the Instrument c ced ete teet tee ete etat ee etetelt Let tec ee ors 15 19 Performing A Histogram
238. ecause the frame length of element letter S is one point Line 3 shows the equation TO AO DO The addition function produces an array but the frame characteristics of the channels are different In this case Snap Master checks the default option for the function being used When the Oversampling option is selected which is the recommended option Snap Master oversamples channel AO to match the sampling rates of the two elements In addition the shorter frame length is assigned to the result element letter As a result the result element letter T has a sample rate of 200 Hz from channel DO and a frame length of 100 points from channel AO If Undersampling option was selected then Snap Master would undersample channel DO and element letter T would have a sample rate of 100 Hz and a frame length of 100 points The shortest frame length is always selected Finally the Block function also affects the output length of the frame In this case the frame length for element letter Q is the frame length of element letter A divided by the block size 100 points per frame 10 points per block 10 points per frame for element letter Q The Correlation function also affects the frame length for the result element letter Analysis and Frequency Analysis Page 12 11 Check Now Auto Check 12 2 Functions Function Name Whenever you enter or change an equation in the equation table Snap Master must check the equation for errors before runn
239. econd AII channels in the instrument are available for D A output Hardware pacing outputs a new data point at precise time intervals using a dedicated pacing clock on the D A hardware The output rate of the data then relies on the capabilities of the D A hardware to perform high speed data transfer between Snap Master and the board If this control does not appear software pacing is used Driving Channel When Hardware pacing is used this determines which channels are available for output Only channels that share the same element letter as the Driving Channel can be selected in the Channel Assignments table as listed in the Available Channels list Page 11 2 Snap Master User s Manual Output Rate When a Driving Channel is selected the Sample Rate portion of the frame characteristics are used to set the Default rate You can specify a different update rate using Manual and entering the new rate Buffer Prefill For Hardware Pacing this specifies the amount of data sent to the D A output buffers before actual signal generation begins The size of the buffer may be specified as a Duration or as a Number Of Points This prefill buffer is used to keep a certain amount of data available for the D A while more data is made ready for it If the D A empties the buffer before the driving element can fill it a D A Underrun error is sent to the Status Log Channel Assignments Input Assigns a data channel from Snap Master to the O
240. ed use the equation range S0 S0 100 A0 Page 12 40 Snap Master User s Manual 12 8 Tutorial Defining Your Own Functions Defining A New Function When you have an equation that you want to use for multiple channels you can create a convenient name for the calculation and create a new function for the Analysis element using the Define keyword We will take the Block Average calculation from a couple of sections back and create a simple function call Analysis Untitled lolx File Edit View Settings Builder Help Ejea e Eae be 7 ox P1 blockavg A0 a Run Comments Equation Definition Label Units 1 1 Block Average Fun kavalinput block 20 avafinput Sioa talrange S0 50 1 00 40 AQ Figure 12 30 Analysis Window with User Defined Function 1 Position the selection box in the first row of the equation table 2 Insert a new line in the equation table by pressing the button or using the Edit menu Insert command All user defined functions must be located at the top of the equation table 3 Press the button or select the Builder menu to open the Equation Builder Analysis Equation Builder Line 1 Equation define blockavg input block 20 avo input Quick Functions H E find or Tee Lr O z 5 block range Define Function Builders Category Statistical 4 Function R
241. edo Copy Copy All Insert Delete Append Insert Stage Find Replace View Menu Command Bar Status Bar Table Columns Snap Master User s Manual Saves the current settings in this dialog as the default method When the Print command is issued the default settings are used Closes the element window This does not remove the element from the instrument Reverses the last action performed Reverses the last Undo performed For table based elements copies the current row as text Copies the entire contents of the table as text Adds a new row in the table at the current row shifting all rows below the current row down Deletes the currently selected rows from the table Appends a new row in the table Add a new stage before the current stage Finds the next instance of the specified text Replaces the next instance of a text string with the specified text Turn the Command Bar on or off Turn the Status Bar on or off Column View View Name iit Columns xl New View Visible Columns Hidden Columns Output Channel Active t Stage Length Stage Units gt Channel Label Channel Units n Cancel Help Figure 2 13 Table Columns View The Table Columns View settings configures which columns are visible in each table by View name Each table has its own separate views and visible columns Creating A New View e Select the New View button e Enter the name of the new view Snap Mas
242. ee Psp eer Time Sec Al vs AD Frame 1 1 Time Sec 5 o Al Nolts N E 0 Voltage Volts 10 Stopped instrument C SM DEFUSER EXAMPLE1 INS 11 10 97 11 39 45 AM Figure 3 32 Displaying Multiple Plot Types The Display window should now include all three plot types Notice that the titles reflect the different plot types by indicating the dependent and independent variables for each set of axes To further customize the appearance of the Display window you may want to alter the title of the plot manually set the range of displayed values display a legend change the grid lines and tick marks and change the colors of the different plots These settings are controlled with the Plot Settings X Axis Settings and Y Axis Settings dialog boxes Remember that you can right click on the plot to select these dialog boxes or double click on the item you wish to change We will change some of these settings to show you how to use the dialog boxes nmm Plot Settings Y vs T Title Channel A0 from A D Demo Iv Show Title I Use Default Sub Title I Show Sub Title Plotting Technique Fonts F X Axis Settings de i Item Title n Draw Lines zl Select Font Channel Settings r Show r Colors T Legend Item Text a S
243. ee that we need a total of four stages for the complete waveform The first step is to add the stages we need 2 Position the selection box in the second row for channel A1 Waveform column then press the button three times or select the Edit menu Append Stage command Page 5 14 Configuring Each Waveform Stage Snap Master User s Manual Now that we have added new stages to the channel we can set up the waveform and duration for the different stages 1 Position the selection box in the second row Waveform column From the pull down list select Constant 2 Press the button select the Settings menu Waveform Settings command or double click on the Waveform table entry for the first stage of channel A1 Constant Settings C Hold Previous Value New Constant Value o Volts cmt Figure 5 22 Stage 1 Constant Settings 3 Change the New Constant Value to 0 4 Press the OK button to close the Constant Settings According to the table we want the value to remain at 0 for one second so let s set the duration 5 Position the selection box in the second row Stage Length column and enter 1 Now let s set up the ramp from 0 to 5 volts which happens between 1 and 3 seconds This makes our stage length 2 seconds 6 Position the selection box in the third row Waveform column From the pull down list select Ramp 8 Press the button select the Settings menu Waveform Settings command or double click
244. eese ee eene esee enses ee ens esee eos sese esse see sessesessssseeese 7713 7 1 Sensor Database er The Sensor element performs linear data scaling conversion to engineering units and assigning of channel names for incoming data The integrated Sensor Database provides a central location where you keep track of all of your in house sensors and transducers their properties and a calibration history The Sensor element is also useful for scaling the output of linear non programmable signal conditioning NOTES You only need one Sensor element per instrument DO NOT delete all of the Sensors from the database If you do not want to use the default sensors that come with Snap Master add at least one of your own sensors before deleting the default sensors from the database Sensor Assignment Table Sensor Specifications Table Figure 7 1 Relationship between Sensor Specifications and Assignment Tables The Sensor element consists of a relational database containing all of the sensors that you own This database is separated into three tables the Sensor Assignments table the Sensor Specifications table and the Calibration History table The Sensor Assignments table assigns the sensors from the database to input channels in the instrument applying the scaling terms and engineering units to the data The Sensor Specifications table is where you insert modify and delete sensors from the database Finally the Calibration History
245. efinition coii ionis wmn RE 11 11 97 10 25 49 AM Figure 13 4 Command Element Table Equations 1 Position the selection box in the Equation Definition column of the first row With the keyboard type Zf A0 lt 0 Then then press ENTER If an arrow appears in the text do not worry This means the Auto Check option is turned on and Snap Master is telling us that we have entered an incomplete statement which is true We will finish the statement on the next lines 2 Position the selection box in the Equation Definition column of the second row With the keyboard type Message Channel AO below 0 Stop test then press ENTER 3 Position the selection box in the Equation Definition column of the second row With the keyboard type Stop then press ENTER 4 Position the selection box in the Equation Definition column of the second row With the keyboard type End If then press ENTER Now that our statement is complete there should be no errors in the table If there are double check the equations 5 Close the Command equation table using the File menu Close command 6 Save the instrument with the button or with the File menu Save command Command Turning Off Status Messages For The Instrument Running The Instrument Page 13 11 In order to get our error message text to appear in the Display window s Status Bar we need to turn off the Status Messages for the instrument window Th
246. ements eeee esee eene eee nete ee eee ens esee en esse sens esee sens sso sose see sssesessssseeess sss 10 Configuring A Counter To Measure Frequency eeeeeeseeeeeeeeeeeereeneneen eene neret nene enne nnne 9 10 Signal Connections 5 2 uo rufa e D e Sos REED ERE FORET TERR FEE EE E OPERE EDD ERE 9 11 Running The Instrument e a er ep t t LO DERE P EESE EEA REA 9 12 Alternate Frequency Measurement Method essere nennen nennen nennen enne 9 12 9 4 Overview Of The 9513 e eeeeeeee eese eee eee tentent en sten sen sens senses senses seen senses seen sen sseseseoseeeneeeseeess Dn 14 Source Gate and Outputs ernia E e Tee HE e E tret ea Ro e d REI Ded 9 14 Load and Hold Registers 2 ote aeter pt e Hr erst a e RE eR E 9 15 TerminialCount GE RnB ERES 9 15 MoOde8 i reri pedet tete ea eese Fete reet iet le eie mein heii PRU Bd ai cide vente 9 15 Chapter 10 RS 232 Answers To Commonly Asked Questions eese enne nenen nne enenr enne enne 10 1 RS 232 Settings ceres String Assignments cin eie cede HR Te E EHE av aio e etis e elec ses er teer Contigur ti nic ied bet eb tete te ete ve ete tex sub ted ek sate e rire ete Ree er ee AAE 10 2 Tutorial Writing Example RS 232 Strings Table of Contents Page vii Chapter 11 Data Output 11 1 Analog Output D A sisisscsssscestsctscseassdscovassesescesesssassssssseccssesvasesseveas
247. ements in the instrument 3 Activate Pipe Mode with the button or select the Element menu Pipe Mode command 4 Connect the A D Demo element to the Analysis element and the Analysis element to the Display element 5 Turn off Pipe Mode with the button or select the Element menu Pipe Mode command Analysis and Frequency Analysis Page 12 29 6 Save the instrument with the button or select the File menu Save Instrument As command Save the instrument as GAEXI The remainder of this tutorial deals with the Analysis element only If you want to change any of the parameters for the other elements please refer to the tutorials in the related chapter The figures shown in this text will be formatted to best illustrate the results of the tutorial Building The 1 Open the Analysis element by double clicking on the icon in the instrument window Equation Analysis Untitled File Edit View Settings Builder Help amp es amp e E aee be E ox Addition Sample Comments Equation Definition Al Addition Sample R onin ien e ico 9i se i 2 i E 2 TT Figure 12 10 Analysis Window with Addition Equation These tutorials concentrate on using the Equation Builder which is best used with a mouse or other pointing device If you are only using the keyboard you can enter the equation directly in the equation table Position the
248. en when the instrument is On Start run When turned off the table remains visible Table Height Sets the amount of space allocated for the table When the table is Cursor Link shown in its own window that window is sizable Determines if linked cursors and markers move Time Aligned using Movement the same X Axis value for all linked cursors and markers or Relative Difference where the delta between X Axis values is maintained as the cursors or markers are moved In the Display element there are two Retrace Modes Buffer Retrace and Full Retrace A Buffer Retrace uses the data stored in the temporary data buffers used by Snap Master The size of this buffer depends on the element producing the data For most acquisition elements such as an A D element the buffer size is 16 384 aggregate points divide by the number of channels For the Disk In element the buffer size is 4096 points If the Analysis element is calculating values the Block Size located in the Element Parameters table determines the buffer size For large data sets especially from the Disk In element the Full Retrace option is useful Full Retrace goes out to the data file in Disk Out and essentially replays the data file to display the complete viewing area Also if the data is from an acquisition element a different buffer is read that provides more data than the Buffer Retrace The Analysis element only has the Block Size data stored in memory so a Full
249. ent Output Power 2 n rede uen RI es ts ieee ds ee ies eek deve side teeta oe 14 9 ran ster Function sees e ueste c nol en eel eei As BO cee hs cata A EUM sank ee otusl s putida 14 9 Table of Contents Page ix Conipliance 2 3 angi edt ieee bec ag p GP ee p HO Reihe gp dpi 14 10 Iinpedan e is 4d eco d ee eoe e ette tee e tet e T o 14 10 Dynamic Compressibility 2 eee Shee Bye Se eret ee Pe Peer i erae ede ed 14 10 Bulk Modul S ere dete e edocti edite e eee tee d c tet d re e ete tet RT RE EG 14 10 Admittance MEM 14 10 Dynainc Elexibility eee rtt i e EU ee Pei dte Pete i ied 14 10 Mobility E S 14 11 Dynamic Accelerance iu ete tete ete e tea t e e te a ted EXE ee x ee ee eng 14 11 Dynamic Stiffniess toii eO Hg eO EGO E RELIER d 14 11 Transimissibilty i edet ete eie e ee ete eee Fete eu e edet eet e dede meg 14 11 IER EUCOLNE 14 11 14 3 Window eer 14 11 Selecting A Window Type ost aee a tas bested eda E doa 14 12 ANndow Widtli Respornse eee repere perte e t e eere te eeetet i beet etit ete tren 14 13 Window Effects Hhustrated ccccesccccsssseccesssccessnceceesssesceessseseseesseceneeseecsnnssesssensseceesnsescsenteeeenses 14 14 Bl ckin anz ee eee eet tee A e tene Ue ex etie d De RI EX A eee 14 16 Blacknian Harris ote iei ertt tir ie eie i dte e re ert rete dens 14 17 Bohman usen enden Ree dedit dede
250. ent to the Display element 5 Turn off Pipe Mode with the button or select the Element menu Pipe Mode command 6 Save the instrument with the button or select the File menu Save Instrument As command Save the instrument as WAVEGEN Wave Generator Setting Up A Page 5 11 Waveform 1 Open the Wave Generator table by double clicking on the element uj Wave Generator Untitled Elle Edi View Settings Help Els js Sj oY o x Sine a Output Active Waveform Stage Stage Channel Channel Channel Length Units Label Units A0 iYes 10 000 Sec oltage Volt Edit current frame acquisition settings Figure 5 17 Wave Generator Settings Before we set up the sine wave let s change the sample rate and frame duration for the element 2 Press the button or select the Settings menu Frame Settings command Frame Settings Sample Rate 100 Frame Length Duration 10 Sec C t of Points 1000 fH points Number of Frames C Continuous Stop After 1 E frames INE Sec Figure 5 18 Wave Generator Frame Settings 3 Change the Sample Rate to 100 4 Change the Duration to 10 seconds 5 Press the OK button to close the Frame Settings If you look in the first row for Channel AO the Waveform is already set to Sine Let s see what the parameters are for the sine wave 6 Position the selection box in t
251. ent window then they are connected together with data pipes With the arrangement of the elements under your control it is easy to see where the flexibility and power of Snap Master comes together An instrument is a flow chart diagram where each element represents a specific function and the data pipes show how the data moves between elements Each piece of the test setup is represented by a unique element icon such as the monitor of the computer which is represented by the Display element The flow chart represents an overview of the instrument s functionality To look at the details behind each element simply double click on the icon to open up the settings When you include a new element in the instrument notice that each element is assigned a unique element letter which appears in brackets before the element name These letters are used to distinguish between elements of the same type for example if two A D Boards are used in the same instrument and to designate data channels to and from each element Channels are always referenced by their element letter and channel number in Snap Master for example channel AO is channel number 0 from element letter A The workspace can have multiple instruments open but only one instrument is running at one time When you press the Start button or select the Start menu command the active instrument window is the one that is started You can view the contents of the other instruments loaded in the w
252. er Terminator gt n The first six tokens HOUR through YEAR and the last three tokens ALARM through COUNTER are Place Holders and are ignored by Snap Master which is indicated by the single quotes used to describe them The characters between the single quotes are not important and could have been called anything such as A B C etc However we have opted to include a meaningful description of the token The seventh token CHO indicates that this is a value to be assigned to channel 0 of this element By including this CHO token the channel list in the Settings dialog will contain AO or whatever the element letter of this element is Each time a Query is sent the response is read and this token will be converted to a new data point for channel 0 of the element If the channel is selected in the Channel list then other elements in the Snap Master instrument have access to this data Because the Hydra Data Logger only returns one point of data per query in this configuration the Multiple Query check box is turned on This means that the Query string is sent at the interval specified in the Sample Interval text box in the Pacing group of the Settings dialog Data Output Page 11 1 Chapter 11 Data Output 11 1 Analog Output D A wssssiscedssccsesssscssoacsscossansaseusntensstonssvsucascessuestesaneessssusuestessaussdeusanseseesassedevsassseuosaessaussseasavesseseceasee 11 1 11 2 Digital OUt e
253. er is calculating a message box tells you that the cells can not be edited Signal Conditioning Page 7 9 4 Press the Insert button Insert Sensor Sensor ID HEM 001 Description r Scaling Kind T C ej Factor 1 Type J zi Offset 0 Serial 1t oo Minimum 0 Model Maximum 50 Manufacturer Engineering Units C z Max Input Frequency x Outpt r Calibration Minimum 10 Interval 100 days Eie 10 Last Cal Date 11 7 10 7 97 mm dd yy Units Volts Cancel Help Figure 7 10 Insert Sensor Dialog Box 5 Enter HEM 001 in the Sensor ID field Remember that the Sensor ID is required because it is the primary sort key for the Sensor Database This ID must be unique from all other sensors in the database 6 Set the Kind to T C Thermocouple and the Type to J For this example we are going to set up a type J thermocouple that converts a voltage to a temperature These items are included in the drop down list or you can enter your own information The Kind and Type information has no effect on the actual scaling of the data but it does help us keep track of the different entries in the database 7 Set the Calibration Interval to 700 days This interval along with the Last Cal Date sets the Next Cal Date for the sensor which is listed in the Sensor Assignments window If this sensor is used past the Next Cal Date without being recalibrated the Status Log will ap
254. er of Frames to Stop After 1 frame 8 From the Device list selecting SawTooth The SawTooth function calculates its period from the Sample Rate and Number of Points and these settings only use a fraction of the cycle As a result the output for this example is an increasing ramp function 9 Press the OK button 10 Save the instrument with the button or select the File menu Save Instrument command Calculating the Tamem Cross Power File Edi View Settings Builder Help sjm E J Spectrum EH SUMI S MO Result Function i Ch2 Window Window Window Starting DC o Frames Avg Partial Ch Width Overla Point Frame Figure 14 19 FFT Settings for Cross Power Spectrum 1 Open the FFT element by double clicking on the icon in the instrument window 2 Position the selection box in the third row 3 Open the Equation Builder by pressing the button or select the Builder menu command FFT Running the Instrument Page 14 33 FFT Equation Builder Line 3 Frequency Domain Calculation Besult Channel MO Volts Category Function Forward FFT Z General Inverse FFT Hydraulic Auto Power Spectrum Electrical Auto Power Spectral Densit Mechanical Cross Power Spectrum hd Ch 1 Channel A0 Volts Ch 2 Channel Do Vots r Scaling Window Result Frame Se
255. er to draw just the data points using the Draw Points option or to connect the data points using Draw Lines Display X Axis Settings Page 3 5 Average Averages every n points and plots the average value where the number of points skipped is specified in the Points field You can specify whether to draw just the data points using the Draw Points option or to connect the data points using Draw Lines Automatic Finds the minimum and maximum values in successive blocks of n points and draws a vertical line between the two points The number of points in each block is calculated based on the current resolution of your video i e 800x600 which is measured in pixels Min Max Finds the minimum and maximum values in successive blocks of n points and draws a vertical line between the two points The number of points in each block is specified in the Points field Show Each plot may contain its own Legend located either inside the plot grid or in the right margin outside the grid If the Legend is located inside the grid it can be moved freely within the grid If it is located in the margin the Legend cannot be moved When Frame Number is selected it appears in the upper right corner of the individual plot window Fonts And Colors Different elements of each plot can have unique Font and Color settings To change from the current setting select the item from the provided list and press the appropriate button The standard Windows dial
256. erence between the elements is the type of data output with the Digital In element outputting digital data Channel Assignments Input Assigns a data channel from Snap Master to the Output bit Output Specifies the output bit on the device This column is not editable The output bits appears as entries in the table in the order of Least Significant Bit LSB to Most Significant Bit MSB When the value of the input channel is greater than or equal to 1 the digital bit is set to 1 True When the value is less than 1 then the digital bit is set to 0 False Inactive State Specifies the state of a digital output bit between frames and when the instrument stops The available options are 0 False 1 True and HOLD which retains the last state of the digital output bit when the frame ends or the instrument stops Page 11 4 Snap Master User s Manual 11 3 Tutorial Outputting Analog Data Building the Instrument In this tutorial we will output the simple 0 5 Hz sine wave from the A D Demo element over a D A channel To verify the signal output through the D A we will acquire the output of the D A using the A D function of the hardware If you do not have A D hardware you could hook up an oscilloscope or meter to the D A output A D A D e D R 4 4 D Demo B 4 D Device C Display D D A Device Figure 11 3 Instrument for Analog Output Tutorial 1 Create a new instrument with the g button or select the File menu N
257. es One Range For All Channels Programmable input ranges JL To Channel Range Sensor Units Cancel Help Figure 8 7 A D Input Ranges Separate Range Per Channel If your A D hardware supports programmable input ranges the Input Ranges button opens one of the Input Ranges dialog boxes For hardware that has one programmable input range for all channels the dialog box shown in Figure 8 6 is used to set the range For hardware that allows a separate range per channel the dialog box shown in Figure 8 7 is used with the range selected from the table s drop down list in the upper left corner If your A D hardware s input range is set by hardware jumpers a dialog box appears informing you of the current settings Memory Allocation Points Per Channel Standard 8192 Complete Frame 500 C Pre Trigger Data 100 C Custom 1000000 om em on Figure 8 8 Memory Allocation Settings The Memory Allocation settings determines how many data points per channel are stored in memory This setting affects the Pre Triggering function in the Triggers dialog as well as the Retrace function in the Display element NOTE The Memory Allocation settings are included for advanced users If you are unsure how to use the different options the safest selection is to use the Standard setting Page 8 10 Snap Master User s Manual There are four options to set the number of da
258. es to load the counter with a value other than the Load Register Also a 16 bit value Count Determines if the counter counts Up or Down on a Source edge A Terminal Count T C occurs when the Counter reaches 0 In the Up case 0 is the next value after 65535 T C Reload Determines which register is used to reset the counter Load Only uses the value of the Load Register and is the most commonly used option Load Hold toggles between the Load and Hold registers and is used mostly for frequency shift keying and variable duty cycle rate generation Cycle Determines what happens when the counter is reset Once lets the counter reach Terminal Count T C once then disables itself until the next data frame Repeat resets the counter to the appropriate register after each T C and restarts the counting function Format Determines the counting method for the counter as either Binary each 4 bit group counts from 0 to 15 where the groups are either the lower or upper half of the 8 bit word or BCD each 4 bit group counts from 0 to 9 Binary is the option used in most cases Special Gate When Enabled the Gate input interacts with the Reload and Cycle settings depending on the mode 9513 Modes N O Q R S V and X This sets up a hardware latch that provides extremely accurate readings lt 1uS error When Disabled a software latch is used to respond to an interrupt pulse There is an indeterminate time delay between the time an interrup
259. esceesseecseecsseecseescecseecesecseecesaeeeaesesaeecsaeesaeesseeeessaes 4 19 Fast Binary Data File Format ssrin ciet eie tenderet eros EE E eder deb eoe nee ea abdo Deed 4 20 Comma Separated Variable Data File Format sees ener nennen 4 21 ASCII Plotter Data File Format 20 0 0 ces cesceseccesceneceesececsscesceecsncecenecsscecenaeensecesesecsasereeessanecseereneesene 4 21 Binary Plotter Data File Format 0 cccccccesccceesececeeeeceeneeeceaeeecensneecsaceeeeseaeecnneeeeeeaeeesnaeeesseneeeseneeeess 4 22 Page iv Snap Master User s Manual Chapter 5 Wave Generator Command ERR 5 1 Table Golumns 235 5 Is git else ev a RENI dad 5 2 EE RATS II MAE Amplitude Modul tion 3 11 1 ect tei tate nere peores eH Eon eee dis eor eee te EE Le Hd 5 3 Besselae ense e stel e toe ete totales ec ete tese texte aus oan ts nto ue tU oe eee end ue m LUE UH et UN eS 5 3 Settings Menu 5 3 Tutorial Creating A Sine Wave Building the Instrument Setting Up A Waveform Running the Instrument 5 4 Tutorial Using Multiple Stages eese eee e eese e ee eee ee eerte esee een esee sens esee enses eeoss see eessesessssseeeseese 97 1 3 Creating Waveform Stages sut egit tec dieri oul t get edet met medo gei ania trt Eee Ss 5 13 Configuring Each Waveform Stage esses eene enne enne nne AEREA a R a 5 14 Ru nng the Instrument
260. escribe hardware I O elements that are the core of Snap Master s Data Acquisition module All of the hardware elements A D Digital In D A Digital Out and Counter Timer share similarities in their user interface There are two possible user interfaces for hardware elements a table interface and a dialog interface used in older versions of Snap Master You can select which interface you want to use from the Global Settings dialog in the Snap Master workspace The table interface is preferred but there are some older hardware drivers which do not support the table interface 8 1 Analog Input A D m The A D element converts analog voltage signals from the real world into digital numbers that can be processed by the computer Snap Master allows you to use multiple A D devices in an instrument This hardware and all input devices must be properly configured in both hardware and software for proper data acquisition Please refer to the hardware documentation for information on its features and its use with Snap Master A Device 1 A2D Settings Untitled G x Fie Edi View Settings Device Help 0 000 Channel Active Factor Min Max Label Units AD Ye al 30 TO trenne Mol Ad Veg 30 7 710 Channel 1 alts A2 Yes 430i WiChannel2 Volts ages 10 Channel 3 Ad No hs No Ab No No Figure 8 1 A D Settings
261. escription Returns a single point which is the average value of all points in argument1 OK Cancel He Figure 12 33 Function Builder for Average 9 Type input as the argument for the Average function The function argument in this case is input which we will supply when we call the function 10 Press the OK button to close the Average Function Builder 11 Type 20 in the Points edit control 12 Press the OK button to close the Block Function Builder and return to the Equation Builder 13 Press the OK button to close the Equation Builder 14 Position the selection box in the first row Comments column Type Block Average Function then press ENTER 15 Switch to the main Snap Master window and save the instrument using the button or the File menu Save Instrument command Now that our function has been defined we can call it in any other calculation even other function definitions just like one of the built in functions 1 Position the selection box in the sixth row Equation Definition column 2 Using the keyboard type P blockavg AO then press ENTER Our function blockavg has one argument which is the input channel The syntax looks identical to other functions in Snap Master which have a single argument Note the Equation Builder is only used for the built in functions of the Analysis element so you must type any user defined functions directly in the equation table Page 12 42 Running the Instrument
262. esults argl arg2 Result False AND False False False AND True False True AND False False True AND True True OR argl or arg2 Example If AO gt 40 or Al gt 50 Then D3 1 End If The OR function compares the current point in arg with the current point in arg2 producing the following results argl arg2 Result False OR False False False OR True True True OR False True True OR True True XOR argl xor arg2 Example If A0 gt 40 xor A1 gt 50 Then D3 1 End If The XOR function compares the current point in arg with the current point in arg2 producing the following results argl arg2 Result False XOR False False False XOR True True True XOR False True True XOR True False Command NOT Actions Set Result Channel Value Set State Variable Value Page 13 7 not arg1 Example If not A0 gt 40 Then D3 1 End If The NOT function produces the logical opposite for the comparison of the current point in argl producing the following results argl Result NOT False True NOT True False The AND OR XOR and NOT operators can be combined in the same IF statement such as If C1 gt 40 and C2 gt 60 or not C3220 xor C4 lt 3 Then D3 21 End If Once the Command element has made a decision an action is performed based on the decision The following actions can be executed by the Command element result channel result constant Examples If A0 gt 40 Then D3 AO Else
263. etc At a sample rate of 10 Hz the resolution is 10 Hz so you can resolve all multiples of 10 10 20 1000 1010 etc An alternate method of measuring frequency requires using the output of an additional counter to gate the frequency channel instead of the Internal Pacer channel The advantage to this method is the resolution of the frequency measurement is independent of the sampling rate As with the first method an Internal Pacer counter is required and its output is tied to the Interrupt Input In this case the output of the Pacer counter is not tied to the gate of the frequency measurement counter Counter Timer Page 9 13 9513 Setup r Configuration Connections 9513 Chip Source F1 1 MHz zi Prescaler Binary C BCD Count On Risma Edge Falling Edge I FOUT Enabled Gate None E muss Z output Hi T C Pulse zl Source Divider g Registers Counter Settings Load Register 10000 Hold Register Counter Count Down C Up Function C Internal Pacer T C Reload C Load Only C Load Hold Usage Pacer xi Cycle C Once Repeat CMede p F Format Binary C BED C Custom Special Gate Disabled C Enabled Cancel Help Figure 9 11 Configuring a Pacer Channel The additional counter assume counter 2 should be configured as a Pacer by setting the Usage to Pacer Set the Load Register for co
264. eturns the remainder portion for the current point of arg1 divided by the current point of arg2 The frame characteristics for the function result are determined by the Options We recommend that the Oversampling option is always used for the Default Option for this function round arg1 Example RO round AO The Round function returns a whole number where the fractional portion of the current point of argl is rounded to the nearest integer The frame characteristics for the function result are determined by argl trunc arg1 Example RO trunc A0 The Truncate function returns the integer portion for the current point of arg1 The frame characteristics for the function result are determined by argl info type arg1 Delimiters type A frame characteristic of arg Example RO info t AO The Channel Information function returns a constant containing the value of the specified frame characteristic for arg DO NOT use the output of the Channel Information function to define the frame characteristics of a result element letter Page 12 26 Pi Pulse Snap Master User s Manual For the Analysis element the available types of information available Type Syntax Description Sample Rate S Sample rate of arg1 Points Per Frame p Frame duration in points of arg1 Total Time Per Frame t Frame duration in seconds of arg1 For the Frequency Analysis element the available types of information available Type Syntax Description Re
265. ew Instrument command in the Snap Master workspace 2 Place the A D Demo element an A D element a Display element and a D A element in the instrument You will need to use the pop up menu in the Toolbox to place both the A D Demo and an A D device in the instrument The menu selection that has a check mark by it indicates which A D board will be placed in the instrument when the icon is dragged to the instrument window To change the selection click on the desired driver 3 Activate Pipe Mode with the button or select the Element menu Pipe Mode command 4 Connect the A D Demo to the A D hardware element the A D hardware element to the Display element and the Display element to the D A hardware element Remember that data flows through elements so we will still be able to plot the A D hardware information 5 Turn off Pipe Mode with the button or select the Element menu Pipe Mode command 6 Save the instrument with the button or select the File menu Save Instrument As command Save the instrument as D2A Data Output Page 11 5 Configuring the 1 Open the A D Demo Settings by double clicking on the A element A D Demo A D Settings Pacing Channel List Type Software E E Location CIntemal C External ra Sample Rate 100 7Sec Pacing unis ee z X Axis Label Time Triggers Free Running dim p Input Ranges 10 to 10 Volts 1t of Points po Hemneyis Standard Number of Frames
266. ew connection must be made There are three types of DDE links a Cold or Manual link a Warm link and a Hot link The different links define how and when the DDE transfer of data occurs The conversation contents for all types are the same but the Client requesting application controls the link type When the link is a Cold link the client requests the data from the server only In other words the client application polls the DDE server for the data If the data changes in the server application between requests the client does not receive the new data until an update command is made by the client A Warm link is similar to a Cold link because the Client application must manually request the new data The difference is in a Warm link the server notifies the client that the data has changed but does not actually send the data until the client requests it The most automated DDE link type is the Hot link When the data changes in the server application the server automatically sends the new information to the client This way the data is consistent between the two applications This is the most automatic of the DDE types but it also requires the most processing time by the operating system to complete Now that we have seen how DDE works in general let s look at how it works with Snap Master At the highest level Snap Master acts as both a client requesting information from other applications and a server sending data to other appl
267. eyboard users you must open the Display Layout table move the selection box in the table to the desired plot then open the Channel Settings dialog 1 If the Display window for the instrument EXAMPLE is not open double click on the Display icon in the instrument window Let s change the color of the channel in the upper left corner Y T plot 2 Move the mouse pointer over the upper left plot labeled AO vs Time and click with the right mouse button Select the Channel Settings item from the popup menu Another quick way to access the Channel Settings dialog is to hold down the CTRL key and double click on the plot If you do not hold this key down when you double click the Plot Settings dialog opens 3 Select a new color for the waveform from the Line Color list Notice that you can only have one color per waveform 4 Press the OK button to accept the new color If you do not want to accept the new color press the Cancel button to retain the previous selection Before we start the instrument to see the effect of our changes let s change the appearance of another channel For those of you using a monochrome screen the color selection might not make much difference but the thickness will 5 Open the Channel Settings dialog for the upper right plot labeled A1 vs Time 6 Change the line Thickness to 2 The Thickness setting determines how wide the line is drawn If you make the line too thick the performanc
268. f the row you want to copy then back again Remember that changes are written either when you move to a new row or close the Sensor Specifications dialog box with the OK button 1 Move the selection box to the ID cell of the sensor you want to copy 2 Enter the new ID number for the sensor you want to add to the database then press ENTER The new sensor is entered and the database is resorted so the new sensor appears in its proper alphabetical order Hints If you own a sensor that has multiple uses or input units specify a different ID number for each function For example if you use one sensor to measure PSI for one test and kPa for another test you could use HEM 101A and HEM 101B respectively as ID numbers For non linear sensors such as thermocouples connected to external signal conditioning modules specify the input range of the sensor and the output range of the signal conditioning module Itis possible to use the Sensor element simply to scale the Y Axis values and assign units and names for plotting using the Display element All that is needed to accomplish this are a few mythical sensors in the database We will set up sensors with a Factor of 1 and an offset of 0 which results in no scaling of the data Follow the same instructions given for adding a sensor to the Select Factor and Offset for the Automatic Calculation then set up these values ID Specify a separate ID number for each input channel We suggest that
269. face R EXAMP ojx Sample Instrument AD A A D Demo B Display Figure 2 15 Your First Instrument Snap Master Basics Creating a New Instrument Page 2 17 1 If any instruments are open in the workspace close them using the File menu Close Instrument command 2 If the Toolbox containing the element icons is not visible select the View menu Toolbox command This places the Toolbox containing the available element icons on the left side of the Snap Master workspace When the Toolbox is open a check mark appears next to the Toolbox menu item 3 Create a new instrument with the button or select the File menu New Instrument command in the Snap Master workspace This opens a clean untitled instrument window in the workspace 4 Type Sample Instrument in the Comment Field The Comment Field is a place where you can type information about the instrument To type comments use the mouse to position the arrow cursor over this field then click the left mouse button A flashing vertical bar will appear in the comment field When this vertical bar is present you can type the information in to the comment field Instrument Settings r Comments C None C One Line r Background Select Color Picture Location C Upper Left C Centered C Tiled Clear Picture Iv Status Messages pe Help If the Comment Field is not visible double click in the instrument window o
270. for an IIR filter The order specifies defines the number of filter coefficients used which affects the slope in the filter s transition bands For IIR filters this order value is analogous to the order of an analog filter The higher the order the steeper the slope of the filter in the transition band the range of frequencies between the pass band and stop band frequencies However higher filter orders require longer processing time The type specifies the response type of the filter This setting also affects if the f2 parameter is used only Band Pass and Band Reject use the f2 parameter The available types are as follows Type Syntax Description Low Pass l Pass frequencies below f1 High Pass h Pass frequencies above f1 Band Pass p Pass frequencies between f1 and f2 Band Reject r Pass frequencies below f1 and above f2 The family parameter specifies the characteristic of the IIR filter in the pass band and the stop band When there is ripple in either the pass band or the stop band the transition band is much smaller in other words the filter has a steeper rolloff This setting also affects if the p1 and p2 parameters are used to specify the amount of ripple The available families are as follows Family Syntax Description Butterworth b Flat pass band rolloff not as steep Chebyshev t Pass band ripple p1 Elliptic e Pass band ripple p1 and stop band loss p2 Inverse Chebyshev i Stop band loss p1 Page 12 22 Time Functi
271. frames m cont te Figure 15 21 Wave Generator Frame Settings 4 Set the Sample Rate to 100 Hz 5 Set the Duration to 10 seconds 6 Select the OK button to close the Frame Settings 7 Open the Waveform Settings dialog by pressing the button in the Command Bar or selecting the Settings menu Waveform Settings command Utility Elements Configuring The Smoothing Element Page 15 15 Sine Settings Sine Parameters 7 Frequency C Constant ONE Hz Linear Sweep Initia I Hz Log Sweep Final 5 Hz Amplitude 10 Volts Rectify Damping Off Linear C Exponential Coefficient 2 DC Offset 0 Volts Phase Degrees Cancel Help Figure 15 22 Waveform Settings for Swept Sine Wave 8 Select the Linear Sweep mode 9 Select the OK button to close the Sine Settings 10 Close the Wave Generator element by selecting the File menu Close Wave Generator command 1 Open the Smoothing dialog box by double clicking on the element Smoothing Settings z Yes Figure 15 23 Thermocouple Linearization Settings 2 Set the Driving Channel to AO This lets us scale all channels with the element letter A in the Input Channel column 3 Position the selection box in the Input Channel column of the first row Select channel AO from the list 4 Position the selection box in the Active column of the first row then select channel Yes from
272. g additional channels from the Secondary list lets you see the corresponding Y axis values for overplotted waveforms at the same X axis value The Secondary list shows either the Plotted Channels those that are on the same plot or All Channels all channels coming in to the Display element When Select All Secondary Channels is turned on in the Default Settings dialog for the Display all channels are selected when you drop the cursor Placing and using a marker uses similar procedures to a cursor When placing a marker the mouse pointer changes to Markers are similar to cursors except that instead of being able to view the relative difference between points a marker can have a text description of the point The data for the marker appears in the Cursor Data window Marker Settings Labet Mare Label Appearance Background Transparent zl Label Font Position Horizontal C Left C Center Right Vertical Top Center Bottom Symbol Appearance J Fill Solid Symbol Color Shape C Rectangle Ellipse Height 3 width 3 Skip Every 1 points Delete Marker OK Cancel Help Figure 3 23 Marker Settings Dialog Box The Marker Settings dialog box configures the appearance of both the marker symbol and the attached label The Skip Rate and Delete Marker controls are the same as in the Cursor Setup dialog box but each cursor and marker has its own settings The symbol s general appearance is con
273. g box e Serial numbers from the Snap Master installation disks If at all possible you should have immediate access to your computer and Snap Master while you are calling This helps the technical support representative quickly determine if a proposed solution is valid as well as gather additional information as needed You may be asked to send additional information to help us assist you such as copies of the Snap Master instrument files data files or photocopies of the original Snap Master diskettes As indicated previously technical support for Snap Master is a service provided by the party from whom you purchased the software In combination with the user s manuals for the software and hardware technical support is intended to assist you to attain useful operation of Snap Master While not a complete list the following paragraphs should give you an idea of the services to expect from HEM Data s Technical Support staff e Answers to General Usability Questions HEM Data s Technical Support staff will answer general usability questions which are defined as non programming issues including product features menu commands formatting and aspects of the user interface use of the windows dialog boxes etc We will also answer general installation questions for both the software and any I O hardware sold directly by HEM Data e Resolution of Repeatable Problems While Snap Master has endured thousands of hours of testing and millio
274. g their response Use this figure as a guideline in comparing the different window types for use in your particular application Each window type is described in more detail in the following sections and includes pictures of the frequency response for each window The Main Lobe Width is expressed in terms of Spectral Lines where the resolution of the frequency domain result is a function of the sample rate of the source data and the window width In general the larger the number of spectral lines in the main lobe at the frequency being measured the larger the bandwidth of the window If skirted is listed in the table which means there are no appreciable side lobes then the window has a wide bandwidth The Side Lobe Height lists the peak amount of attenuation at the first side lobe from the main lobe Attenuation of the side lobes affects the amount of energy shown at frequencies adjacent to high strength signals which becomes important for signals with signal components that are close together For windows that are skirted the lowest amplitude response is listed If any window type other than the Rectangular window is used some of the energy from the time domain is eliminated As a result the apparent magnitude in the FFT would appear to be less than the magnitude in the time domain Therefore if a 1 0 volt sine wave is the input the results should be corrected so that the amplitude at the frequency of the sine wave is 1 0 volt
275. g2 and produces a value of 1 if the comparison is true or a value of 0 is the comparison is false The frame characteristics for the function result are determined by the Options We recommend that the Oversampling option is always used for the Default Option for this function The valid comparisons are as follows Comparison Syntax Description lt argl lt arg2 Less than lt arg lt arg2 Less than or equal to argl arg2 Equal to gt arg gt arg2 Greater than or equal to gt argl gt arg2 Greater than lt gt argl lt gt arg2 Not equal to if argl true result false result Example RO if A0 gt 5 A0 0 RO if A0 5 and A1 lt 2 A0 0 The If function performs the contents of arg1 and treats it as a Boolean result If arg1 is equal to 1 the result of the function is the contents of true result If argl is equal to 0 the result of the function is the contents of false result Page 12 20 Find Event Filters Smoothing Filter FIR Filter Snap Master User s Manual find argl Options p Frame Point Number t Frame Time Analysis or Frequency Frequency Analysis Examples SO find A0 gt 5 SO find t A0 gt 5 The Find function locates the first data point where the contents of arg1 are satisfied and produces either the point number in the frame or the X axis location time or frequency of the event The output of the function is a single point The contents of arg will usually be a Comparison o
276. ge and Find functions you can use Snap Master to intelligently process your data In this tutorial we will see how to integrate over a specific range of points where the range is determined by looking at the incoming data values Analysis Untitled Beles File Edit View Settings Builder Help ajla e Eee e 7 ox Al intgfrange S0 S0 100 A0 Run Comments Equation Definition Label Units Sample Al Added i 0 j find 0 lt 0 i Fii intajranae 5 SO Toan i 11 11 97 10 05 24 AM Figure 12 25 Analysis Window with Integration Over A Range 1 Position the selection box in the fourth row of the equation table 2 Press the button or select the Builder menu to open the Equation Builder Analysis Equation Builder Line 4 Equation ri intg range S0 S0 100 A0 a Quick Functions E nd or e Lr O z A05 block range Define Function Builders Statistical Filters Syntax intg argumentl Description Calculates the area under the curve of argument with respect to time Previous Line Cancel Help Next Line Figure 12 26 Equation Builder with Integration Over A Range 3 Position the mouse pointer over the Equation edit control and press the right mouse button to open the On Screen Keypad 4 Select the Channel radio button 5 Select the letter R fr
277. gent Differentiation Integration Y X Integration Correlation Average Maximum Minimum Root Mean Sqr Std Deviation Variance Running Avg Runing Max Running Min Running RMS AND OR XOR Comparison NOT If Then Else Find Time Of Event argl arg2 argl arg2 arg arg2 argl arg2 arg arg2 abs arg 1 sqrt arg1 exp arg log arg1 In arg1 cos arg1 sin arg1 tan arg1 acos arg1 asin arg1 atan arg 1 diff arg1 intg arg1 intgyx argl arg2 arg1 corr arg2 avg argl max arg1 min arg1 rms argl std arg1 var arg 1 ravg arg1 rmax arg1 rmin arg1 rrms argl argl and arg2 argl or arg2 argl xor arg2 argl compare arg2 not arg1 if argl true res false res find arg1 Oversampling Undersampling Degrees Radians Grads 2 Point 3 Point 5 Point 1st Order Taylor 2nd Order Taylor 4th Order Taylor Rectangular Simpson s Rule Trapezoidal a order Adams Bashforth 1 6 g order Gear s 1 6 area under the curve of arg with respect to arg2 Oversampling Undersampling produces single point result produces array result o Oversampling u Undersampling compare lt lt gt gt lt gt true 1 false 0 values gt 1 are true arg gt 1 produces true res arg 1 produces false res p Frame Point Number t Frame Time Page 12 3 FIR Filter IIR Filter Frame Time Time Shift Fraction Round Tru
278. ger 1 ScreenCopy Display Page 2 ScreenCopy Desktop 3 High Res Black amp White 4 High Res Color string Yes No string Yes No string Yes No instrument DefaultPrintHiResSepLines instrument DefaultPrintHiResWindowTitle instrument DefaultPrintHiResDateTime instrument DefaultPrintLeftMargin instrument DefaultPrintRightMargin instrument DefaultPrintTopMargin instrument DefaultPrintBottomMargin single single single NOR CNN RRR RRR RUN UR single Page D 6 Snap Master User s Manual Layout Page Settings Topic Item Exec Req Poke Format Comments instrument Page PageDefaultTitle string Yes No replace Page with Page and number in column i e Pagel Pageft Title string Page AutoRows string Yes No Page Rows integer Page AutoCols string Yes No Page Cols integer Layout Display Layout Topic Item Exec Req Poke Format Comments NumPlots integer number of plots defines in the layout table Plot Page integer replace Plot with Plot and number in column i e Plot5 None or 1 8 Plot PlotType string Plot ChList string CSV list of channels in plot Topic Item Exec Req Poke Format Comments Plot Title string Plot TitleState integer 0 Show No Title 1 Show Default Title 2 Show User Supplied Title Plot SubTitle string Plot ShowSubTitle string Yes No Plot TechniqueMode integer contents of Plotting
279. gits set the number of digits on either side of the decimal point The Time Of Day 12 hr and Time Of Day 24 hr formats show the wall clock time of the frame Times are entered as hr mm ss with and AM or PM radio button for the 12 hour format When the Time Fraction checkbox is selected the fractional portion of the seconds is shown When you plot data that was acquired using Pre Triggering the actual trigger point is located at time 0 on the display Any pre trigger data appears before time 0 This works either with data coming directly from the acquisition element or from a data file read by the Disk In element Display Y Axis Settings Page 3 7 Major Divisions Major Divisions Defines the appearance of the values grid lines and tick marks on the plot The major divisions are spaced equidistantly from the Axis Location Show As Vertical Grid displays a line across the entire plot region at each major division Tick Mark shows only a small line along the axis at each major division None does not display the locations of the major divisions Show Axis When selected displays the value at either the Minimum and Values Maximum of the axis or at All Major Divisions Minor Divisions Minor Divisions Defines the number of subdivisions for each major division Show As Tick Mark shows a small line along the axis at each minor division None does not display the locations of the minor divisions
280. gs 7 Open the Waveform Settings dialog by pressing the button in the Command Bar or selecting the Settings menu Waveform Settings command Page 15 10 Snap Master User s Manual Linearizing Thermocouple Channels Sine Settings r Sine Parameters Frequency Constant ho Hz C Linear Sweep Initia e C Log Sweep Final bo Hz Amplitude o 05 Volts Rectify Damping Off Linear C Exponential Coefficient 2 DC Offset 0 02 volts Phase f Degrees Cance Help Figure 15 13 Waveform Settings for Sine Wave 8 Set the Amplitude to 0 05 Volts 9 Set the DC Offset to 0 02 Volts 10 Select the OK button to close the Sine Settings 11 Close the Wave Generator element by selecting the File menu Close Wave Generator command 1 Open the TCLinear dialog box by double clicking on the element Thermocouple Linearizer Settings Driving Channel 0 Voltage CJC Settings Area 1 4 Result Active Input Type Temperature Label Un Channel Channel Units B Voltage K s Figure 15 14 Thermocouple Linearization Settings 2 Set the Driving Channel to AO This lets us scale all channels with the element letter A in the Input Channel column 3 Position the selection box in the Input Channel column of the first row Select channel AO from the list 4 Position the selection box in the Active column of th
281. h frequency between plus and minus pi The Plot Settings X Axis Settings Y Axis Settings and Channel Settings dialogs for frequency domain plots function the same as the dialogs used for Y T plots Because the X axis basis is different you cannot overplot time domain with frequency domain data The Y vs X and Scatter plot types are similar to the time domain plots except that they use an input channel as the basis for the X axis These plot types are considered to be a time domain plots because all channels have the time variable in common Y X plots use the same Plot Settings Y Axis Settings and Channel Settings dialogs as Y T plots X Axis Settings Labet Voltage Volts M ShowLabel Use Default Scale Major Divisions Type Linear Major Divisions 5 E Logarithmic Show As Vertical Grid a Location v 0 x M Auto Clear None Iv Show Axis Values r Range Minimum and Maximum T Default Scale C All Major Divisions Minimum 5 Volts DES 5 Volts r Minor Divisions Format Default zl inis Hi g Significant Digits i 3 T VES Cancel Help Figure 3 6 X Axis Settings Y vs X Axis X Axis Channel Defines the channel used for the basis of the X axis Each channel specified in the Display Layout table is plotted against the X Axis Channel using the same time reference the value of the channel at time t versus the value of the X Axi
282. hange the values back to 50 Hz and 200 points before continuing FFT Untitled Beles File Edi View Settings Builder Help EG j ra 8j Go a Result Function Ch1 Ch2 Window Window Window Starting DC Avg Frames Avg Partial Type Width Overla Point Frame TTT Figure 14 14 FFT Settings for Inverse FFT Tutorial 1 Open the FFT element by double clicking on the icon in the instrument window 2 Position the selection box in the second row Page 14 30 Snap Master User s Manual 3 Open the Equation Builder by pressing the button or select the Builder menu command FFT Equation Builder Line 2 Frequency Domain Calculation Result Channel G0 Volts Category Function General Inverse FFT Hydraulic Auto Power Spectrum Electrical Auto Power Spectral Density Mechanical Cross Power Spectrum E Chi Chomer A vo Ch 2 not used g r Scaling Window Result Frame Settings Window Width 1024 fHpoints Start At Point Overlap points Spectral Resolution 0 0039 Hz F Include DE Component Type Parabolic FS Foren Average Spectra Across 0 frames Riemann Partial Frame Zero Extend Ignore Description Specifies the first channel used by the function lt lt Previous Line Cancel Heb Next Line gt gt Figure 14 15 FFT Equation Builder Settings for
283. hannel see Waveform Analyzer Module The standard bus used for controlling electronic instruments with a computer Also called IEEE 488 bus An intuitive easy to use way of communicating information to and from a computer program by means of graphical screen displays GUIs can resemble the front panels of instruments or other objects associated with a computer program The physical components of a computer system such as the circuit boards plug in boards chassis enclosures peripherals cables etc A numbering system to the base 16 An icon is a symbolic representation of active applications that are not in their full window form For example to open the Snap Master program double click on its icon Also each Snap Master element has an associated icon which acts as an indicator of the element s functions See GPIB Resistance to flow of alternating current measured in ohms reactive The Instrument window is where elements are connected together with data pipes Each of the elements settings are accessible by double clicking on their icon in the Instrument Window Page A 6 Interrupt Input Output I O Linearity Lists Literal Match Math Coprocessor Maximize Box Memory Menu Command Buttons Menus Microsoft Windows Minimize Box Multiplexer Mux Multitasking Snap Master User s Manual A computer signal indicating that the CPU should suspend its current task to service a designated
284. hannel A10 is the third channel in the list which is item 2 in a 0 based sequence If ChOffset is replaced by the value 1 the complete header string is returned for all channels Page D 12 D 7 Disk Out Topic Item Exec instrument NamingStyle FileName FileSaveAlIChannels FileSaveChannel instrument instrument instrument FileComments FileFormat instrument instrument StartAtFrame StopAtFrame Continuous PauseAfter Paced PlaybackSpeed instrument instrument instrument instrument instrument instrument D 8 DDE Out Item Exec DDEOut ChNum data DDEOut ChNum xLabel DDEOut ChNum xUnits DDEOut ChNum points DDEOut ChNum rate DDEOut ChNum frameNumber DDEOut ChNum yLabel DDEOut ChNum yUnits DDEOut ChNum factor DDEOut ChNum offset DDEOut ChNum yMin DDEOut ChNum yMax Topic instrument instrument instrument instrument instrument instrument instrument instrument instrument instrument instrument instrument Notes Req SORUN XU zx 2 KA RR aK Poke SNARK KK Poke Format string string string string string string long int long int string long int string integer Format string string string string string string string string string string string string Snap Master User s Manual Comments DateTime SeedName Ordinary full path and file name Yes No space delimited list of valid channels for example A0 A1 A2 RO S0 Exponential
285. hannel AD gt Channel A1 gt 0 000812 1 View Seng Start Window Heb ie Element Lo B IA A D Demo IB DDE Out Figure 6 13 DDE Data Transfer from Snap Master to Excel Try to size the Snap Master window and the Excel window so you can view both at the same time To start the instrument switch back to Snap Master and press the Start menu command About once every second a new value appears in the Excel cells you linked to This information is passed from the A D Demo element through the DDE Out element and finally to Excel Dynamic Data Exchange Page 6 17 6 5 Tutorial Using Block Mode Now that we have seen how one data point is transferred into a cell how do we paste data into a column One way in Excel is to write a macro using the ON DATA function This function performs a set of commands when a new data point is sent over a DDE Link But that requires learning how to write Macro code Luckily there is an easier way to move data into a column Using the Block Mode capability of the DDE Out element and the same Copy Paste Link function from the previous section we can send entire blocks of data to Excel Modifying the xi Instrument m amp D Demo B DDE Out Figure 6 14 Instrument for Block Mode Tutorial We will use the same instrument from the previous section changing only one parameter in the instrument Before we continue let s save the instrument as a new fi
286. he Relay element s output frame is completed the Relay element appends zeros to complete the frame Channel List Channels which are highlighted in the Channel List are passed through when the Relay is activated The element letter for the output channels is the element letter of the Relay element and the channel number is the same number as shown in the Channel List Auto Toggle Settings r Toggle When r Trigger Condition Type Channel Value zi Condition Channel AO zl Above zi jpbrezmnogerng Level One 2 Volts Triggering 0 T Bre Triggering s C Level Two 0 Volts Specify As Points C Seconds C Frame Length Cancel Help Figure 15 2 Auto Toggle Settings Toggle When The Toggle When Type setting determines the criteria used to activate the Relay element so it activates and passes data to other elements The Channel Value selection uses the Channel and Trigger Condition settings to emulate an analog trigger like the one used by the Analog Input element The DDE Command selection activates the Relay element when a ToggleNow command is sent to the Element Refer to Appendix D for more information on using DDE commands with Snap Master Pre Triggering Pre Triggering When selected specifies the amount of data included in the data frame that occurred immediately before the trigger condition was satisfied Specify As Selects if the Pre Triggering amount is specified
287. he Snap Master workspace 2 Place the A D Demo and DDE Out elements in the instrument 3 Activate Pipe Mode with the button or select the Element menu Pipe Mode command Dynamic Data Exchange Configuring the A D Demo Copying the DDE Link Page 6 15 4 Connect the A D Demo element to the DDE Out element 5 Turn off Pipe Mode with the button or select the Element menu Pipe Mode command 6 Save the instrument with the button or select the File menu Save Instrument As command Save the instrument as DDEOUT 1 Open the A D Demo Settings by double clicking on the element A D Settings Pacing 3 Channel List 1 Type Software E Pel Location Internal C External ra Sample Rate 1 7 Sec Pacing Units Sec zl X Axis Label Time Tiriggers Free Running Frame Length Input Ranges 18 to 10 Volts Duration 200 Sec 1t of Points po Memory stondura Device r Number of Frames C Continuous Sine z Stop After fi frames Configuration Status Messages oe temm _ no Figure 6 11 A D Demo Settings 2 Change the Sample Rate to 1 3 Change the Number of Frames to Stop After 1 frame 4 Press the OK button to close the A D Demo Settings 1 Open the DDE Out Settings by double clicking on the element DDE Out Settings DDE Items Channel Item a 1 xLabel 2 xUnits points 3 rate frameNumber Z
288. he current Date and Time or any Status Messages from the Status Log appear in the bar When you are debugging an instrument s operation you may want to turn on the Status Messages check box to display all messages such as Waiting for Trigger etc The Font Selection button select the font and point size for that window s Status Bar Begins operation of the active instrument When the instrument is running the menu changes to include only the Stop command Show all instrument title bars Show all instruments Immediately arranges the icons in both the instrument window and the workspace according to the Icon Spacing setting Open the Snap Master Help contents How to use the Windows Help program Open the Snap Master Help tutorials Page 2 10 About Snap Master 2 2 Elements Overview of Elements About Snap Master Snap Master User s Manual 1391 1997 HEM Data Corporation r Libraries Demo Elements v3 20 Disk 1 0 v3 20a Display v3 20a DDE 1 0 v3 20 Wave Generator v3 20 Relay v3 20a Sensor Database v3 20 RS 232 v3 20 Smooth v3 20 Thermocouple Linearizer v3 20 Analysis 3 20a Event Counting 3 20a MultiFrame v3 20 Command v3 20 FFT v3 21 2 Freq Analysis v3 20a x Product Information User Name Fred Brown III rganization HEM Data Corporation Version 32 Build 2 r System Information Version DOS 7 0 wFw 3 95 Windows Mode 386 Enhanced Free Memory 32 252 kB Free Syste
289. he edge of the Gate to determine when to count and reset the counter Reload Source At the beginning of each frame the value of the Gate determines if the initial value of the counter is set to the Load register or the Hold register If the Gate is Low then the counter is set to the Load register value and if the Gate is High then the counter is set to the Hold register value The counter then accumulates to the first T C and reloads the value as determined by the gate Counting continues until the second T C after which the counter is disarmed until the next frame occurs Frequency Shift Keying This mode performs the same function as Mode S except that the counter is reloaded after every T C Again the Gate determines which register is loaded Low Load High Hold Frequency shift keying is accomplished by setting the Output to the T C Toggled signal The frequency switching occurs by modulating the Gate At the beginning of each frame the value of the Gate determines if the initial value of the counter is set to the Load register or the Hold register If the Gate is Low then the counter is set to the Load register Hardware Save This mode is available only with Counter Timer hardware based on the Am9513A At the beginning of each frame the value of the Load register is transferred to the counter Counting begins on the first Gate edge where the Gate condition is satisfied Each subsequent Gate edge causes the counter value to be tr
290. he first row then press the button select the Settings menu Waveform Settings command or double click on the Waveform table entry for channel AO Page 5 12 Running the Instrument Snap Master User s Manual Sine Settings r Sine Parameters Frequency Constant S Hz C Linear Sweep Initial a Hz ClogSweep Fini gt He Amplitude 10 Volts Rectify Damping Off Linear C Exponential Coefficient 2 DC Offset o Volts Phase o Degrees teca e Figure 5 19 Sine Settings 7 Set the Frequency to 5 Hz 8 Press the OK button to close the Sine Settings Now that out sine wave is configured we need to assign a channel name and activate the channel 9 Position the selection box in the first row for Channel AO Channel Label column and enter Sine Wave 10 Position the selection box in the first row for Channel AO Active column From the pull down list select Yes to activate the channel 11 Close the Wave Generator table using the File menu Close Wave Generator command Display Page 1 Jol Fie Edit View Settings Start Layout Cursor Help Voltage vs Time Frame 1 z Ss 2 S E Time Sec Switch to Display Page 1 11 10 57 2 03 54 PM Figure 5 20 Results of Wave Generator Tutorial When you run the instrument the sine wave appears as data comes in from the
291. he phase part for each data point When Snap Master writes the data file the FFT BLOCKSIZE is equal to the number of data points in the frame The data in the file is written according to the following format Section Contains File Header Introduction Parameter Name and Value List Data Frame Frame Header Magnitude Part Phase Part Data Frame Frame Header Magnitude Part Phase Part Data Frame Frame Header Magnitude Part Phase Part Page 4 20 Sample Standard Binary Data File Fast Binary Data File Format Snap Master Data File 17 COMMENT 9 A comment DATES 12 04 21 1992 TIMES 10 15 38 45 ACT FREQ 2 10 ACT SWEEP 1 2 NCHANS 1 4 CHANS 14 A0 Al A2 A3 NUM POINTS 3 20 CLOCK UNITS 3 Sec FILE TYPES 25 Interleaved Analog Binary INTERLEAVE FACTOR 2 4 CONVERSION POLYS 30 0 1x 0 1x UNITSS 26 Volts Volts Volts DEFAULT LABELS 10 1 1 1 1 CHANNEL LABELS 34 Voltage Voltage CHANNEL TYPES 14 yt yt yt CHANNEL RANGES 38 10 10 10 10 DATAINFOS 126 Board Type DAS 16 Clock Type Internal Trigger Type Free Running Resolution 12 Bit TR 1 04 21 1992 15 39245 TR 2 04 21 1992 L53738 746 Snap Master User s Manual Introduction Comment Line Parameter Variables and Values 0 1x 0 1x Voltage Voltage LO yO 20y DOF Frame Header Binar
292. he reason is that Snap Master s equation syntax is designed to work in the same fashion as you think In general you build the equation exactly as you would speak it perform a block average Block Calculation block ava A0 ees Block Size Format Default Points el Points Time Points 2o T Overlap 10 g Syntax block Points D verlap argumentt Description Specifies the amount of data per block as either a number or a calculated result Cancel Help Figure 12 17 Function Builder for Block Now that we have the Block Function builder open we need access to the Average Function Builder It is easy to nest functions in the Equation and Function Builders using the button 11 Press the Fal button select the Statistical item Single Value item and Average item to open the Average Function Builder Average Single Value Calculation avg A0 es Quick Functions x Syntax avg argumentl Description Returns a single point which is the average value of all points in argument Lox ce me Figure 12 18 Function Builder for Average 12 Press the button and click on channel AO This is all we need for the Average function so we can close it and return to the Block Function Builder and set the number of points per block 13 Press the OK button to close the Average Function Builder 14 Change the Points to 20 15 Press the OK button to close the Block Function Builder
293. he signal connected to the selected Gate input is High Available for either the previous counter the current counter or the next counter Lo Level Gate n means the gate condition is satisfied when the signal connected to the current Gate input is Low Hi Edge Gate n means the gate condition is satisfied when the signal connected to the current Gate input changes from Low to High Lo Edge Gate n means the gate condition is satisfied when the signal connected to the current Gate input changes from High to Low Also the Special Gate setting in the Registers group determines if the Gate is used to retrigger the count by resetting the counter with the value from the appropriate register Defines the signal sent to the output of the counter Always Hi means the output is a constant TTL high Always Lo means the output is a constant TTL low Hi T C Pulse means the output is normally low and changes to high when the Terminal Count event occurs Lo T C Pulse means the output is normally high and changes to low when the Terminal Count event occurs T C Toggle means the output inverts high to low or low to high when each Terminal Count event occurs Page 9 6 Snap Master User s Manual Registers Load Register Register for a 16 bit value 0 to 65535 used to set the initial count for the counter on a Terminal Count Hold Register Register used by Snap Master to read the current value of the counter Also used for certain mod
294. he size of the page Function Snap Master Function Definition Secant Define sec x 1 cos x Cosecant Define cosec x 1 sin x Cotangent Define cotan x 1 tan x Hyperbolic Sine Define hsin x exp x exp x 2 Hyperbolic Cosine Define hcos x exp x exp x Hyperbolic Tangent Define htan x exp x exp x exp x exp x Hyperbolic Secant Define hsec 2 exp x exp x Hyperbolic Cosecant Define oe 2 exp x texp x Hyperbolic Define hcotan ae exp x exp x exp x exp x Cotangent PID Define pid in out P I D P in out I intg in out D diff in out in input channel out output channel 12 4 Tutorial Adding Two Channels Building the Instrument This series of tutorials assume that the has a working knowledge of Snap Master In addition to these tutorial sections there are a number of sample equation files that you may use for reference or to begin customizing your own equations All of these tutorials are based on the Analysis element If you only own the Frequency Analyzer module you can substitute an FFT element between the A D Demo element and the Frequency Analysis element to generate frequency domain data to follow along 4 4 D Demo B Analysis C Display Figure 12 9 Instrument for Analysis Tutorials 1 Create a new instrument with the E button or select the File menu New Instrument command in the Snap Master workspace 2 Place the A D Demo Analysis and Display el
295. hile the Clipboard is useful for fairly static information it is still a manual operation for the user to move information from one application to another Another Windows mechanism for sharing information is Dynamic Data Exchange DDE which communicates using links Dynamic Data Dynamic Data Exchange or DDE is a step beyond the Clipboard because it automates the Exchange DDE transfer of information between applications This communication is based on a link between two applications which acts as a personal clipboard between the applications DDE is built into the Windows operating environment so any program that has built in DDE capabilities can share information with another DDE capable program DDE is a communication standard for software programs just as RS 232 and GPIB allows different hardware to communicate Thus far the generic term information has been used to describe what is being passed between programs With Snap Master and DDE we can now split this out into three distinct categories commands parameters and data Using DDE one program can send commands such as load the instrument start the instrument etc to control how another application is used Parameters such as sample rate data file name equation number etc can be changed via DDE to customize the application Finally actual data from an input element analyzed channels cursor information etc can be sent between applications Page 6 2 DDE Clients
296. his is also used to set the Label in Snap Master for the channel Type Specifies the type of data stored in the tag In Snap Master you can only read numeric type data 16 3 Tutorial Using The IndustrialSQL In Element Building the Instrument This tutorial discusses how to access data from and IndustrialSQL Server database Before continuing the tutorial make sure that the IndustrialSQL Server is running and that you have the proper access rights to the database A Industrial QL In B Display Figure 16 5 Instrument for IndustrialSQL In Tutorial 1 Create a new instrument with the button or select the File menu New Instrument command in the Snap Master workspace 2 Place the IndustrialSQL In and Display elements in the instrument 3 Activate Pipe Mode with the button or select the Element menu Pipe Mode command 4 Connect the IndustrialSQL In element to the Display element 5 Turn off Pipe Mode with the button or select the Element menu Pipe Mode command 6 Save the instrument with the button or select the File menu Save Instrument As command Save the instrument as ISQLIN IndustrialSQL Connecting to the IndustrialSQL Server Database Activating A Tag Running the Instrument Page 16 5 1 Open the IndustrialSQL In Settings by double clicking on the element 2 Login to the database using the appropriate Server Database Username and Password entries If the connection is successf
297. iation in phase shift or time delay between channels It is important to note that digital filtering does not help alias because the data as already been converted from the analog to the digital domain aliasing and all The digital filter cannot separate a legitimate component from an aliased one because it has no idea what the original signal was As a result anti aliasing filters must be analog filters DDE Commands and Parameters Page D 1 Appendix D DDE Commands and Parameters IS rare EU PC D2 WOLKSPACe e ires S Fra DI TERRITI ITI TEE D4 A D D000 PEEE D 5 Display D 6 Disk In RWW bd DSTI ge MR D 10 A D Device Digital In Counter Timer In eee eeee eese eee eene eee eene eee ene sees ens sesso sse esnss see seose see eesseseesosseeesssss LA DES D A DOViCC qc PM dO ub IEO EE AE DVS El E M i ler Menit RE L7 INI Jp IS LO D 17 Histogram DDE Su pport This appendix lists the DDE commands and parameters available in Snap Master This information is intended for users who are knowledgeable about DDE and who want to use these capabilities in their own macros and programs The service name for these commands is Snap Master with the items listed by topic The standard technical support for Snap Master DOES NOT i
298. ications The three different types of DDE information supported by Snap Master include commands parameters and data For a complete list of DDE information supported by Snap Master refer to Appendix D Commands are used to control the operation of another program Typical commands in Snap Master include load the instrument start the instrument stop the instrument and others Using these DDE commands into Snap Master the user can control how and when Snap Master operates Page 6 4 Snap Master User s Manual Parameters in Snap Master are divided up by each element Essentially a parameter is equivalent to a value defined in a settings dialog box These include the sample rate data file name data file format as well as others The available parameters accepted by Snap Master are also listed in Appendix D When commands and parameters are sent to Snap Master the other application acts as the client because it initiates the conversation Note that we often think of the server as the sender of information but in this case the server is the recipient of the parameter information When you combine commands and parameters in another application you can create a custom human interface to replace Snap Master s standard element icon and dialog box interface This is most useful for presenting the user with a familiar interface The external application could even automate the operation of Snap Master by defining a sequence of events and sendi
299. ice 1 Digital In Settings Untitled Beles File Edi View Settings Device Helpl 11 10 97 4 19 22 PM Figure 8 23 Digital In Settings 2 Press the button or select the Settings menu Frame Settings command Page 8 22 Running the Instrument Snap Master User s Manual Frame Settings r Pacing Frame Length Type Software Duration b o Sec Location C Internal C External C of Points o Sample Rate o Sec Number of Frames Pacing Units Sec H Continuous X Axis Label Time CStopAfter frames Cancel Help Figure 8 24 Frame Settings 4 Set the Sample Rate to 10 5 Change the Frame Length to a Duration of 5 seconds 6 Press the OK button to close the Frame Settings 7 Make sure the first channel or the channel you have your input wired to has a Yes in the Active column 8 Close the Digital Settings window with the File menu Close command 9 Save the instrument with the button or select the File menu Save Instrument command 1 Press the button or the Start menu command If all is well the Display window opens and begins plotting your input signal If the Status Log appears with an ERROR entry follow the remedy listed If all else fails verify the hardware Configuration and your A D Settings The plot shown below has the Major Divisions in both the X axis
300. ies the levels for the various trigger conditions Level 2 Page 15 4 Snap Master User s Manual 15 2 Tutorial Relay Building the Instrument Configuring The Wave Generator This tutorial shows how to control data flow while the instrument is running using the Relay element Instead of the A D Demo we use for most tutorials we will use the Wave Generator to generate a ramp wave So it is easy to see when the Relay element is triggered 4 Wave Generator B Relay C Display Figure 15 3 Instrument for Relay Tutorial 1 Create a new instrument with the E button or select the File menu New Instrument command in the Snap Master workspace 2 Place the Wave Generator Relay and Display elements in the instrument 3 Activate Pipe Mode with the button or select the Element menu Pipe Mode command 4 Connect the Wave Generator element to the Relay element and the Relay element to the Display element 5 Turn off Pipe Mode with the button or select the Element menu Pipe Mode command 6 Save the instrument with the button or select the File menu Save Instrument As command Save the instrument as RELAY a Wave Generator Untitled Biel es Fie Edi View Settings Help ES GS RS a el Ramp Output Active Waveform Stage Stage Channel Length Units iY 1 000 Sec iv i OOS 1 000 Sec 1 000 Sec Channel Channel
301. ies with time and frequency domain analysis and near real time plotting all without programming From high speed data acquisition display and storage to monitoring and control Snap Master has the power to meet the needs of a wide variety of applications Snap Master is divided into three modules Data Acquisition SM DA Waveform Analyzer SM WA formerly known as General Analysis and Frequency Analyzer SM FA Each is a fully functional stand alone package that includes data display storage retrieval and Dynamic Data Exchange DDE capabilities By integrating the different Snap Master modules you can create a complete software solution to meet your total needs NOTE Some chapters and tutorials may contain additional features not included in your Snap Master software For more information on how to obtain these additional features please contact the vendor from whom you purchased Snap Master Included with Snap Master are sample instruments that demonstrate different features of the program To open these files run Snap Master then select the File menu Open Instrument command The Open dialog box will appear with a list of the Instrument files that you can use Try using the Viewer button in the Open dialog to see the contents of each instrument In addition to the instruments included on disk the following instruments represent the Snap Master equivalents for many pieces of conventional equipment It is highly recommended that you
302. ifies the number of points used for the calculation When you leave the text field the Equation Builder checks to make sure the width is valid If it is not a dialog appears asking you to select a valid window width Alternatively use the spin buttons to the right of the text field to scroll through the valid window widths Indicates the frequency separation of each spectral line in the result calculation The resolution is determined by the window width and the sample rate of Ch1 and Ch2 Select a scaling window for the calculation The individual windows are discussed later in this chapter Page 14 4 Snap Master User s Manual Result Frame Settings Start At Point Overlap Remove DC Component Average Spectra Across Frames Determines the first time domain point evaluated by the FFT function This feature is helpful when analyzing an event that does not start at the beginning of a frame or when aligning two separate events Changing the starting point may affect both the magnitude response and phase response of the data This is because in the frequency domain shifting a waveform in time changes the real and imaginary parts of the frequency domain result in such a manner that the magnitude remains constant but the ratio of the imaginary part to the real part varies It is this change in ratio that affects the phase of the result Determines the number of data points from the previous window used in the current window Fo
303. ighlight the current value and enter 3 This setting automatically stops the instrument after collecting three frames of data 4 Press the OK button to accept the changes 5 Save the instrument with the button or select the File menu Save Instrument command 1 Press the button or the Start menu command If you allow the instrument to run its complete course it should stop after the third frame of data Notice that the X Axis labels in the Display window constantly reset themselves to represent the frame time and not the elapsed test time In addition the frame number appears in the upper right corner of the plots to indicate the current frame for the data being displayed Display Page 3 1 Chapter 3 Display 3 1 Display Window sccccsscsssccsscssscsscscessscsseesssccesssscccescsscscessssscssssccsesssccsssssccessssscsssscsscssssssscsssssscssssssscsssssscssssssees OU SQ PlOt Ty Pes csesscscntscacccsscsosssatssesscousssvssansentscacssavesscsenssceccsesotatsensssecsseuecseauassseaseesecavensssaaeseavesesasssacssenscecessessarsoeusdecssaceness OO 3 3 Menu COMMANAG ssccsssrosssscsssecsssevsesscsccsssnsssesssscnssesssssssssssnsssssssscnsssssnsssssesscnssscsssscnsssssssssessssosssscsesscsssssssssseseseO7 LO 3 4 Tutorial Changing the Display Settings 4 eee eee ee eres eese eene eene ennt ets sess sess ss sens se sns se snsse sense esseesns sess s 7 LO 3 5 Tutorial Using Display Pages
304. ight of the side lobe is negligible Triangular Best Case Worst Case Frequency 2 Response 60 dB Bandwidth 3 7 8 28 Spectral Lines Main Lobe Width 3 124 Spectral Lines Side Lobe Height 26 9 dB 85 3 dB As seen in the examples at the beginning of this section the Triangular window has very different responses depending on the location of the frequencies with respect to the spectral lines This window is better suited towards the worst case where the frequencies of interest and the spectral lines do not coincide 14 4 Window Width The other window parameter we can adjust is the window width The window width affects the resolution of the frequency calculation the spectral lines and also affects accuracy of the windowing function by enclosing a complete period of the source waveform The FFT element produces a result frame after the specified number of data points are input from the data channel For example if you have one time domain frame with 10 000 points of data and are performing an FFT function on 4096 points you will output either two or three frames of data depending on the Partial Frames setting If Partial Frames is set to Zero Extend the FFT element produces one frame for the first 4096 point one for the second 4096 points and one for the remaining 1808 points If Partial Frames is set to Drop only the first two result frames are produced FFT Available Widths Frequency Resolution and Spectral Line
305. ignal conditioning hardware and the input hardware the data pipe sends only the scaling information through the instrument For information on your specific hardware please consult the documentation that accompanied your hardware Page 7 8 Snap Master User s Manual 7 4 Tutorial Adding A Sensor To The Sensor Database Building the Instrument Inserting A New Sensor Before we use the Sensor element to scale the data of an incoming channel and assign a label let s add a sensor to the database All editing of the actual Sensor Database occurs from the Sensor Specifications table Once the sensor is included in the database you can assign it any time without having to reenter it When you are done entering your sensors in the master list press the OK button This will save the changes to the last row you have edited Also moving the selection box off of a row writes the last row edited to the database file The Cancel button cancels only the changes made on the last row you have edited 1 Create a new instrument with the button or select the File menu New Instrument command in the Snap Master workspace 2 Place the Sensor element in the instrument If a message box appears on your screen asking you if SHARE EXE is loaded you must exit Windows and run SHARE from the DOS prompt do not run it from a DOS shell within Windows Refer to the Installation section of the manual for more information To add a new sensor to the
306. igure 14 13 Results of Forward FFT Tutorial When you Start the instrument the plot of AO appears in real time but the frequency plot waits until the entire window length is acquired before displaying the information If the plots do not appear you have Auto Layout turned off Configure a y vs t plot for AO and a mag vs f plot for FO Figure 14 13 has been formatted to show the plot of FO from 0 to 5Hz on the X axis with tick marks instead of gridlines To verify the frequency of the input channel place a cursor on the frequency plot using the button At 0 5 Hz an amplitude of 4 998727 volts is displayed and at all other frequencies the magnitude is approximately 0 If you are interested in investigating the effects of window width on the accuracy of the FFT try changing the window width to 180 points or the A D Demo sample rate to 51 This changes many of the window parameters such as the spectral lines making the start and end points unequal and analyzing less than two complete cycles of the source waveform Less accurate results should be displayed in the plot of FO 14 6 Tutorial Performing an Inverse FFT Calculating An Inverse FFT Now that we have a signal in the frequency domain we can convert it back to the time domain and compare it with the original signal The conversion from frequency to time is accomplished using the Inverse FFT function If you changed the A D Demo sample rate or the FFT window width be sure to c
307. imulate analog gauges Histogram Histogram Plot event counting data To customize the appearance of any plot click on the plot with the right mouse button A popup menu lets you select the area of the plot you want to change You can also double click in the center of the plot to open the Plot Settings dialog box If you have any cursors or markers on the plot you must hold down the Shift key and double click the mouse To change the appearance of this and other plots in the Display Layout dialog box select the plot or plots you want to alter and press the Plot Settings button To gain quick access to only the X axis Settings or the Y axis Settings you can also double click on the appropriate axis Each plot type has a default template that consists of all settings for the plot except for the channels assigned to the plot These settings include the channel colors line styles X and Y axis settings plotting techniques fonts etc To make the settings for an existing plot the default click on the plot with the right mouse button and select the Save As Default command from the pop up menu To apply the current default settings for the plot type to a plot right click on the plot and select the Apply Default menu command To automatically apply the defaults each time you create a plot in the Layout turn on the Apply Defaults For New Plots check box in the Default Settings dialog Note that there is only one default template for each plot ty
308. in length from 1 point up to 2 147 483 647 points Page 8 6 Trigger Snap Master User s Manual Number of Frames The Number of Frames group allows you to specify how Snap Master will run the instrument When Continuous is selected the instrument continuously acquires data frames until the user presses the Stop button To have the instrument acquire a specific number of data frames select Stop After and enter the number of frames For example if Stop After is selected with a value of 5 Snap Master will acquire five frames of data and automatically stop the instrument At any time the user can stop the instrument manually Trigger Settings Trigger Mode Trigger Condition Standard Custom Settings 5 C Hardware Dependent Condition 5 4 ide Type Analog Software I C Level One 8 Volts Semmes I 6 Level two 5 Volts T Exclusive Trigger Specify As A D Units C Sensor Units Pre Triggering rc Complex Triggers Iv Pre Triggering po x I Multiple Stage Triggers Insert Uu Specify As C Points C Seconds eser eus Frame Length Delete Down Cancel Help Figure 8 4 Trigger Settings Triggers are used to start a frame based on a specific characteristic of the incoming data There are many different options for triggering which may differ between A D hardware Please refer to the documentation accompanying your hardware for informat
309. in space less than 100 leaves space between each bin When selected the bars are filled with the Color When not selected only the outlines of the bars are drawn or the lines are connected Please refer to Chapter 2 for a description of the common menu commands Immediately prints the current Display page using the default settings Using the keyboard press CTRL P to perform this command Print Setup Print Method Screen Copy High Resoultion Print Display Print Method j Save As Default C Screen Copy Print Areas Display Page Desktop High Resolution Output As Black amp White C Color Include v Separator Lines Iv Window Title IV Date amp Time Print Margin 00000000 Left 1 inches Top fi inches Bight 1 inches Bottom 1 inches Figure 3 16 Print Display Settings Prints a bitmap image of either the current Display Page or the entire Desktop useful for including the Cursor Data window or the workspace The resolution of this printout is the same resolution as your display which is approximately 72 dots per inch Prints the current Display Page using the actual resolution of the printer as either Black amp White all data printed in black against a white background or Color using the colors as they appear on screen In addition the printout can contain Separator Lines between plots the Window Title for the Display Page and the current Date amp Time Display
310. in the Display Page Settings dialog is the number of rows and columns for the page This is where we can change how the plots are arranged in the Display window 1 Position the selection box in the first row Rows column Right now Page 1 has two plots in it By default Snap Master arranges these side by side in one row or two columns If we want each plot to take up the full width of the Display window we can override the default by entering a new number of rows NOTE If you change these settings and add plots to the page at a later time the plots may not appear where you expect them to Make sure the Page Settings match the number of plots configured for the page 2 Enter 2 for the number of Rows With this setting Page 1 will always have two rows when laying out the plots Because we only have two plots each will be placed in its own row 3 Press the Close button to close the Display Page Settings 4 Press the Close button to close the Display Layout dialog box 1 Press the button When you run the instrument notice that Page 1 uses the full width for both plots If you switch between pages while the instrument is running using the buttons only the new data is plotted the full displays do not appear until a new frame begins Hekk Channel AD from A D Demo At Noks Time Sec 2 Al vs Time Frame
311. ind Time Of Event function to define the Start and Stop parameters and similar functions The Analysis element stores between 100 and 16 000 points per channel based on this setting There is a tradeoff between the number of points stored in memory and the speed of the calculations In general the less the number of points stored in memory the slower the calculations will occur and the greater the number of points the faster the calculation We recommend setting the number of points to around 1000 for optimal performance Function Defaults For built in functions that have multiple processing options you may specify the default option used when the function is specified by itself The current default option is indicated by an outlined check mark To change the default select the function from the Function list and double click on the desired option All instruments and Analysis elements share a common set of Default Options This means that is you have two Analysis elements in an instrument or two instruments open each with an Analysis element then they all must have the same default options for each function The Frequency Analysis element has its own default settings which are separate from the Analysis element When you save the instrument or equation file the current default options are also saved When you open an instrument or equation file Snap Master checks the current function defaults in the Analysis element against the defaults
312. indow is where you specify which sensor is connected to an input channel and the label for the channel You can only enter information in the Ch Channel and Label columns the remainder of the information is read from the Sensor Specifications Table columns with a red title can not be edited To assign as sensor from the database find the ID of the sensor you want to assign then move the selection box to the Ch column Pull down the list in the upper left corner of the table and select a channel from the list If the channel you want to assign is not listed it is probably already assigned to a sensor Channels may only be assigned to one sensor at a time and each sensor can only be assigned to one channel at a time If you assign a sensor that is past the date listed in the Next Cal Date column an error message appears in the Status Log informing you that a Sensor ID is out of calibration along with the sensor ID The instrument will operate correctly but your data may not be accurate due to the possibility that the sensor is out of calibration Recalibrate the sensor and enter its new values in the Sensor Specifications table along with a new Cal Date In the Assignment table only the Ch and Label columns are editable If you attempt to edit any other column you will be informed that editing is not available for the cell you have selected To change the value of the other columns use the Sensor Specifications table The following co
313. ine waves or sawtooth waves Use the Device list to select the wave type Selecting the Status Messages check box tells the A D Demo element to send operating messages to the Status Log Under normal operation this option should be turned off If an error is encountered during operation of the instrument the message will be sent to the Status Log regardless of the Status Messages setting 2 6 Tutorial Changing A D Demo Parameters Changing the Sample Rate Let s change the operation of the instrument we built in the previous tutorial by altering the A D Demo parameters This example illustrates the concept of frames in Snap Master and how all of the A D Demo element s parameters interact with each other to form a frame A D Settings Pacing Channel List j Type Software E Ap Location CIntemal Cem Sample Rate 50 4 Sec Pacing Units Sec zl X Axis Label Time Triggers Free Running r Frame Length Input Banges 10 to 10 Volts Duration g Sec C tt of Points po Memory Standard 1 Device 7 r Number of Frames C Continuous Sine z 3 c B Configuration I Status Messages Stop After frames oen tm Figure 2 18 A D Demo Settings 1 If the instrument EXAMPLEI INS or the file name you gave the instrument is not open in the workspace open it using the File menu Open Instrument command 2 Open the A D Demo Settings dialog box by double clicking o
314. ing When the Stop On Error check box is selected any errors underruns or overruns encountered during operation of the instrument causes the instrument to stop immediately When the check box is turned off the element continues operating in spite of the error Data Output 11 2 Digital Out DIG OUT Page 11 3 The Digital Out element controls the digital output channels or bits of digital I O hardware Snap Master allows you to use multiple Digital Output devices in an instrument This hardware must be properly configured in both hardware and software for proper operation Please refer to the hardware documentation for information on its features and its use with Snap Master Digital Out Settings r Pacing r Channel Assignments Type Software zl Location Gintemal Extemal Driving Channel 3 Available Channels Output Rate Default Output Ranges C Manual Hz Device n uita Kizil Slot 1 CIO DAS16 330i a Duration Bee I Status M latus Messages C H of Points SURE iets E OE Cancel Help Figure 11 2 Digital Out Settings The Digital Out Settings dialog operates in the same fashion as the D A Settings dialog box Pacing Buffer Prefill and Device groups have the same meaning for the Digital Out as the D A element If the Pacing and Buffer Prefill groups do not appear assume that the Pacing Type is Software The main diff
315. ing the instrument If you attempt to start the instrument without checking the equations a message box tells you that you must do so before starting the instrument If any errors are encountered while checking an equation one of the following symbols appears in the Run column of the equation table When you double click on the symbol a dialog box appears which explains the error and lets you edit the equation The error symbols and the severity of the error are as follows Symbol Severity Description Warning Does not prevent starting the instrument but the results may e not be what you intended 9 Error Does not allow you to start the instrument without fixing the error o Fatal Error Does not allow you to start the instrument and indicates a critical error Occurs very rarely so you should contact technical support if you receive a Fatal Error message Automatically check the equation table each time it changes Each function is presented in the following format Syntax used to write the equation with the function shown in bold functions that are italicized are replaced as described for the function any required delimiters enclosed in brackets and written in bold italics and the equation arguments Delimiters Any required function delimiters are explained Delimiters always appear in brackets following the function If no delimiters are available this entry is not shown in the user s manual Options The syntax and descr
316. installation program asks for them The installation program will add an icon for the latest installation of Snap Master When installation is completed double click on the new icon to start the program 1 5 Computer Configuration Windows 3 1 Snap Master operates under Microsoft Windows 3 1 If you are using Windows 3 0 you must upgrade to Windows 3 1 before you can run Snap Master The About Snap Master dialog box contains information about Snap Master and the support libraries as well as information about your computer This information can be recalled at any time from the Snap Master workspace with the Help menu About Snap Master command After Snap Master is installed you may need to check the CONFIG SYS and AUTOEXEC BAT files located in the root directory of your startup drive If any of these files are found please read the following information for further details HIMEM SYS This is the extended manager program distributed with MS DOS and Windows All Windows programs use extended memory to access the memory above 640 KB Therefore Snap Master is designed to work with HIMEM SYS Make sure that the following line is contained in the CONFIG SYS file substitute the directory where your copy of HIMEM SYS is stored DEVICE C NWINDOWSWVIIMEM SYS EMM386 EXE This program emulates expanded memory using the installed extended QEMM SYS memory Some non Windows applications use expanded memory but all 386MAX SYS Windows programs
317. ion pl Window Width t Maximum Frequency single value 3 14159 array of 1 at center 0 elsewhere Page 12 4 Snap Master User s Manual 12 1 Menu Commands File Menu Open Settings Merge Equations Please refer to Chapter 2 for a description of the common menu commands When you open a Snap Master equation file the Analysis element checks the current function defaults against the defaults stored in the CLC file or the FCL file for the Frequency Analysis element If they are different a message box appears asking if you want to change the function defaults to the ones stored in the file In order to duplicate a previous test exactly you should accept the changes Importing Snap Calc Files Input Channels 0 becomes 0 Result Channels RO becomes R 0 SObecomes S 0 Cancel Help Figure 12 2 Channel Mappings for Importing Snap Calc Files For SnapShot users Snap Calc files can be imported using the Original Syntax option refer to section 12 1 0 for more information on the syntax options When importing a Snap Calc file the Channel Mappings dialog box defines the input result R and single value S element letters You can change these to the element letters in your particular instrument using the appropriate text boxes Semicolons are not supported in Snap Master Instead you must use parentheses to compose the equation Also if the Time function is used to generate a signal
318. ion on its triggering capabilities The standard software based is best used at lower acquisition rates The response of the triggering function depends on the A D hardware used the speed of the computer the complexity of the instrument as well as other factors If the trigger condition is not sensed try lowering the sample rate or using A D hardware with hardware based triggering capabilities Trigger Mode Standard Software based triggering available for all hardware types Hardware Dependent Special triggering capabilities included by the manufacturer specific to this hardware such as hardware based triggering To access the special settings for these trigger types press the Custom Settings button Type Snap Master Standard trigger types include Free Running the frame begins as soon as Snap Master is ready essentially no trigger and Analog Software uses a trigger condition on an incoming analog input channel to determine when a frame starts Channel Specifies the channel used to look for the trigger condition Exclusive Trigger When selected this element suspends operation of all other elements in the instrument until the trigger condition is met To bypass any trigger conditions while the instrument is running press the Esc key Data Acquisition Trigger Condition Condition Level 1 Level 2 Specify As Page 8 7 Specifies the signal characteristic which generates a positive trigger The standard conditions are
319. ion on the intermediate result When using the Range function you can receive different results based on where you place the range Remember that the function zeroes out all data outside of the range For example the equation RO range 100 200 intg A0 first integrates channel AO then zeroes out the data before point 100 and after 200 At point 100 the integration starts at the value of the integration which may not be 0 This is because of precedence order of the equation A powerful option is to use the Find Event function to automatically determine the start_at and stop_at parameters based on user defined conditions The Find function can be nested directly in the Range arguments or a result channel which uses the Find function to locate an event may be referenced If data appears to be missing from the Range function after the Find function detects the event increase the number of points stored in memory using the Options menu Analysis Settings command Memory Optimization control When a DDE link is used to define the start_at and stop_at parameters the DDE link should not change while the instrument is running After the instrument has stopped the current value in the link is used when a the Display element receives a Retrace command This makes it easy to use Display cursors to define the range over which a calculation occurs and recalculate the results by hitting the Retrace button Hint If you have a specific function that uses a r
320. iption for any optional methods Options are always enclosed in brackets following the function If no options are available this entry is not shown in the user s manual Examples Example equations using the function are illustrated A brief description of the function follows the general information Any further information on the delimiters and options are also described Page 12 12 Arithmetic Functions Addition Subtraction Multiplication Division Power argl arg2 Options o Examples Snap Master User s Manual Oversampling Undersampling R0 A0 Al RO A0 0 Al The Addition function adds the current point in arg to the current point in arg2 The frame characteristics for the function result are determined by the Options We recommend that the Oversampling option is always used for the Default Option for this function argl arg2 Options o u Examples Oversampling Undersampling R0 A0 Al R0 A0 o Al The Subtraction function subtracts the current point in arg2 from the current point in arg The frame characteristics for the function result are determined by the Options We recommend that the Oversampling option is always used for the Default Option for this function arg arg2 Options ee Examples Oversampling Undersampling RO A0 Al RO A0 o Al The Multiplication function multiplies the current point in arg1 by the current point in arg2 The frame characteris
321. is a signal measuring displacement and the denominator Ch2 is a signal measuring force The result units are units for displacement over the units for force such as in Ib The Compliance function is equivalent to Dynamic Flexibility and is the inverse of Dynamic Stiffness Impedance is a special transfer function used in hydraulic electrical and mechanical systems In order to use this function the two input channels must have the same frame characteristics For hydraulic systems the numerator Chl of the calculation is a signal measuring pressure and the denominator Ch2 is a signal measuring flow The result units are units for pressure over the units for flow such as psi gpm Impedance is the inverse of Compliance For electrical systems the numerator Chl of the calculation is a voltage signal and the denominator Ch2 is a current signal The result units are volt amps Impedance is the inverse of Admittance For mechanical systems the numerator Ch1 of the calculation is a signal measuring force and the denominator Ch2 is a signal measuring velocity The result units are units for force over the units for velocity such as Ib in sec The Impedance function is equivalent to Transmissibility and is the inverse of Mobility Generally Impedance is used for parallel combinations of interconnected mechanical elements Dynamic Compressibility is a special transfer function used in hydraulic systems In order to use this function
322. is connected to the same pulse source as the INT IN lead which is our Pacing clock from counter 5 Counter Timer Signal Connections Page 9 11 Each time the INT IN pulse source has a rising edge the counter value is transferred to the Hold Register which Snap Master reads This value is then scaled by the Sample Rate in the Counter Timer Settings dialog to produce a frequency value In this example we are sampling at 100 samples per second so the counter value is multiplied by 100 Note that the best frequency resolution that you can measure is the same as the Sample Rate In this example we can measure no finer an increment in frequency than 100 Hz 7 Select Source 1 from the Source list Since we already have the input signal coming in on Source 1 select it as the input for Counter 2 This means we do not have to make another physical connection for the input channel we still do for the Gate of Counter 2 8 Close the 9513 Settings dialog by pressing the OK button 9 Press the OK button to close the Configuration dialog 10 Close the Counter Timer Settings window with the File menu Close command 11 Switch to the Snap Master window and save the instrument with the button or with the File menu Save command Counter 1 Input Counter 2 Gate Counter 5 Output Digital Common Interrupt Enable The same connections from the previous section are used with one addition The Counter 2 Gate must be connected to
323. is is so the instrument s default messages do not overwrite our own 1 Open the Instrument Settings dialog with the button or with the Settings menu Instrument Settings command Instrument Settings Comments xi C None C One Line C Two Line Background gt gt gt Select Color Select Picture Picture Location C Upper Left C Centered C Tiled Clear Picture Figure 13 5 Command Element Table Equations 2 Turn off the Status Messages check box 3 Press the OK button 4 Save the instrument with the button or with the File menu Save command Before we run the instrument let s clear the Status Log so it will be easier to find our message from the Command element 1 From the Snap Master main window open the Status Log by pressing the button or select the View menu Show Status Log command 2 Press the Clear button then the Exit button 4 Press the button or the Start menu command IE Display Page 1 G x Fie Edi View Settings Start Layout Cursor Help AD vs Time Time Sec 2 Channel AO below D Stop test 11 11 97 102710 AM Figure 13 6 Results of Command Element Tutorial Page 13 12 Snap Master User s Manual When the instrument is started the Display which has been formatted here to show only channel AO shows that the value of channel AO starts at 5 volts When the data
324. ite i oet loe dte 14 17 lent 14 17 Cosine thi POWetr quitte REN RISE e ORA RA IR RR testis 14 18 Cosine T pered iu ene Rn Ee ee ae D E Dna 14 18 Exact Blackitiati sd ne rod t eee tae dC ER ORE EO PORE ER 14 18 EXpOnen tials unie UR tei a ae see eo Seek I gn EACUS 14 19 Extended Cosine Bell nete RA E RE be n S 14 19 Flat TOP E 14 20 CIauS SIdBz o tree tinte n Dv bite due Pvt rd Ota les vedo 14 20 Halt Cycle Sine i Basak len Se Bes ebd s 14 20 lEnnwilpsmc ELEME 14 21 AMD PETAT ILIUM 14 21 H rnning Polssonc c verte DO eg ee ede o cR 14 21 KaiserzBessel zia p siesta cee ce ee nd a Tau 14 22 Parabolic tc xo Dt te eR DAR ete 14 22 wu E H 14 22 POISSOD e nv tird ventre tire tir Dv a D vedi oven Dur v en ub DR Ress 14 23 Derbi EES 14 23 RIG Manny tbt Dtm e titii 14 23 Sire 3rd PoWer 5 T rr RE REA EIE E XE GNIS XE ER TERRE te dus Ene RP Oed NR ARE GNR ER edt 14 24 TEriangularzi eire emer Er ER EP ORE OU ro ER REGERE 14 24 nnno A 14 24 Available Widtliss secat a ER RA RR RM RM CRM o METRE RARUS 14 25 Frequency Resolution and Spectral Lines eeesesesseeeeeeeeeeee eren enne entere neret 14 25 Forcing Periodicity nih ei n o n PPP eei PR RR LER RP ORE 14 25 14 5 Tutorial Performing a Forward FFT Lees esee eese eene esee
325. k Border Figure 3 12 Correct and Incorrect Fill Regions for Bar Meters To define the fill regions click on the Define Fill Regions button Move the mouse pointer into the region where you want the bar meter drawn and click the mouse button To fill more than one area continue clicking in the desired fill regions When you are done press the Exit Define Fill Regions button The Fill Direction setting determines how the bar meter moves in relation to the screen When Vertical is selected the boundaries in the Axis Settings dialog define the Top and Bottom values For Horizontal the boundaries define Left and Right Dial Meter plots display single values using a familiar needle and gauge type display This plot type is useful for data where the value is best displayed in relation to its overall range or when users want the familiar analog gauge look Alarm conditions are indicated by the color bands on the dial itself The majority of the Dial Meter Settings operate the same as the equivalent settings for a Digital Meter The Channel Value and Units are displayed in the bezel underneath the dial meter to show not only the relative value but the actual data value as well The resolution of the Value is fixed to show two numbers after the decimal for more control over the display of the values try using a Digital Meter plot type Fonts and Colors operate the same for Dial Meters as for Digital Meters with one exception The Backg
326. l Equal Not Equal Rising Edge Falling Edge instrument TriggerUnits string Sensor A D instrument TriggerLevels string SAT instrument TriggerLevell Analog single Digital string of binary bit mask instrument TriggerLevel2 Analog single Digital string of binary bit mask instrument TriggerExclusive string Yes No instrument TriggerPreTrigger string Yes No instrument TriggerPreTriggerAs string Points Seconds Frame Length instrument TriggerPreTriggerValue single Notes Hardware Dependent trigger settings are identical to the list items in the Trigger dialog D 11 D A Device Topic Item Exec Req Poke Format Comments instrument NumberOfChannels integer instrument Ch channel string ChannelNumber None instrument Ch nactiveState string value HOLD D 12 Digital Out Topic Item Exec Req Poke Format Comments instrument NumberOfBits integer instrument Ch channel string ChannelNumber None instrument Ch InactiveState string 0 1 HOLD DDE Commands and Parameters D 13 Analysis Topic Item FileNew FileOpen filename FileSave FileSaveAs filename FileClose OptionsCheckNow ActiveEquation Line Comments Line Definition Line Label Line Units OptionsResultOn OptionsAutoCheck ResultLetter Label ResultLetter Units instrument instrument instrument instrument instrument instrument
327. l response would be a single straight line at 100Hz and zero elsewhere FFT Page 14 15 The Rectangular window produces the closest result to the ideal due largely to the fact that the main signal falls on a spectral line In this best case scenario the Rectangular window has a single spectral line at the frequency of interest with an amplitude of 82 dB at 99 and 101 Hz the adjacent spectral lines The Blackman Harris window produces a similar result but the width of the main lobe is greater than the Rectangular window As a result it appears that energy is measured at 3 Hz on either side of the main frequency The Main Lobe Width for the best case is 7 spectral lines for the Blackman Harris window regardless of the frequency resolution so 3 Hz is the net result with our resolution Because the remainder of the spectrum is below 100 dB the overall response is adequate Finally the Triangular window shows the same frequency component at 100 Hz with spill over energy at 1 Hz but it also shows energy at 3 Hz 5 Hz etc In the best case the Triangular window has a small main lobe width of 3 spectral lines but the Side Lobe Height is only 27 dB down from the peak which is much less than the other window types For the case where there is a strong frequency component on a spectral line the Triangular window does not provide the most accurate results Now let s look at a case where the frequencies are far apart bu
328. large number of spectral lines in the 60 dB Bandwidth This window zeroes out the latter part of the time domain data which would otherwise be composed of noise and is often used for stimulus response testing of mechanical structures Extended Cosine Bell Frequency Response 60 dB Bandwidth Spectral Lines Main Lobe Width Spectral Lines Side Lobe Height BSSR Bees BO Best Case 19 45 8 dB 19 50 6 dB BSE Ee ee BO Worst Case 26 51 4 dB 10 34 5 dB Another cosine based window type with ringing around the main lobe Like the Cosine Tapered window the Extended Cosine Bell window has high side lobes with a relatively narrow main lobe width Page 14 20 Snap Master User s Manual Flat Top Best Case Worst Case Frequency Response p 60 dB Bandwidth 9 15 9 dB 187 Spectral Lines Main Lobe Width 26 skirted Spectral Lines Side Lobe Height 109 2 dB 84 7 dB In the best case the Flat Top window often used for calibration purposes has a wider main lobe but most of the energy is below 60 dB In the worst case the response is skirted As a result where the frequencies of interest fall in respect to the spectral lines determines if this window is classified as a wide or narrow band window Gaussian Best Case Worst Case Frequency 2 2 Response 3 60 dB Bandwidth 21 415 Spectral Lines Main Lobe Width 115 2 Spectral Lines Side Lobe Height 88 8 dB 28 4 dB The Gaussian wind
329. lder useful is that you can build the equation by clicking on the Quick Function buttons and double clicking on the Function list items When you click on the button located at the right side of the Equation edit control a pop up list appears which contains the defined channels in the instrument If a channel has been assigned a label then the label also appears in the pop up list To insert a channel in the Equation Line at the current cursor position select the channel from the pop up list The Quick Function buttons are used to insert the most commonly used functions into the Equation edit control or to open the Function Builder where applicable All of the available Quick Function buttons appear in the main Equation Builder In the Function Builders Quick Function buttons that best apply to the function are shown The Category and Function lists organize the functions alphabetically into different groups The All Functions category lists all available functions in the Function list Alternatively you can select a specific category to narrow down the items shown in the Function list When you click once on a function in the Function list the proper Syntax along with any options for the function is shown along with a description about the function To open the Function Builder for the item double click on the list item When you are finished using the Equation Builder press the OK button to write the contents of the Equation edit control
330. le 1 Save the instrument with the File menu Save Instrument As command Save the instrument as DDEBLOCK Copying a DDE 1 Open the DDE Out Settings by double clicking on the element Data Block DDE Out Settings DDE Items Channel A0 Item data a xLabel xUnits points rate frameNumber Z Copy Link To Clipboard Data Points Per Block 10 Points Cancel Help Figure 6 15 DDE Out Settings Block Mode 2 Select channel AO from the Channel list 3 Select data from the Item list 4 Set the Data Points Per Block to 10 points 5 Press the Copy Link To Clipboard button 6 Press the OK button to close the dialog box 7 Switch to Excel 8 Highlight 10 rows in a column then select the Edit menu Paste Special command Set the Source To Paste Link the Text then select OK The DDE Links shown in each cell will look identical Page 6 18 Running the Instrument Snap Master User s Manual Microsoft Excel Book1 SS Fie Edt View Insert Format Tools Data Window Help la x Dele els selee ole zla s gea z obe el Ede l pa Am Aelia sl als O ud A E 1 Snap MasterTCASMIDEFUSERIDDEOUT INSTB AD data D E F G H H C SM DEFUSER DDEGUT INS a IB DDE Out 11 Er i d dg ay ts a a amp Figure 6 16 Block Data Transfer from Snap Master to Excel When you run the instrument from Snap
331. le instrument Condition string Above Below Inside Outside PositiveSlope NegativeSlope instrument Level string One Two instrument LevelOne single instrument LevelTwo single DDE Commands and Parameters D 17 Histogram Topic Item instrument InputChannelType instrument InputChannel instrument CalculationType instrument Threshold instrument OutputBin instrument BinWidth instrument NumberOfBins instrument MaxLimit instrument MinLimit D 18 MultiFrame Topic Item instrument InputChannelType instrument InputChannel instrument FrameCalculationType instrument NumberOfFrames Exec x 2 KSS ALK KAS Page D 19 Y e ke Format Comments string Time Frequency string valid channel number None string Summing Averaging Counting SCR single string BandAnalysis Histogram single integer single single RR ARARAK Poke Format Comments string Time Frequency string valid channel number None string Sum Average long int instrument OutputRate integer PC Computer Information Page E 1 Appendix E PC Computer Information Interrupts IRQ The following table describes the standard PC interrupts listed in order of priority Check the documentation for your computer system and all add in hardware to determine the available interrupts for your computer Priority Interrupt Ty
332. le 0 to 10 V Snap Master module which performs time domain calculations Data can be input from disk files acquired using the Data Acquisition Module or generated using the TIME function A window is a framed rectangular area on a computer screen where you view data Each window contains space to display the window title controls for resizing the window menus and space for a program to run and display data The selected front most window is referred to as the active window The Workspace is also known as the main Snap Master window This is where instrument windows are placed and where the Toolbox resides When you exit Snap Master the current contents of the workspace are saved in a separate file Bibliography Page B 1 Appendix B Bibliography Bendat Julius S and Piersol Allan G Random Data Analysis and Measurement Procedures John Wiley amp Sons New York Brigham E Oran The Fast Fourier Transform Prentice Hall Inc Englewood Cliffs New Jersey 1974 Enochson Sound amp Vibration March 1987 Ewins D J Modal Testing Theory and Practice Research Studies Press 1986 Hamming R W Digital Filters Second Edition Prentice Hall Inc Englewood Cliffs New Jersey 1983 Hewlett Packard Application Note 140 0 How the Fourier Works a Guided Tour of Some Basic Operations Hewlett Packard Application Note 140 1 Detecting Sources of Vibration and Noise Using HP Fourier Analyzers Hewlett Packard Applicatio
333. le Rate field defines how many times per second the A D Demo element generates a value for each channel The maximum sample rate for the A D Demo element is 1000 samples per second Snap Master Basics Frame Length Number of Frames Channel List Device Status Messages Page 2 21 You can define the size of each data frame by specifying either the amount of time or number of data points per frame The frame length is equal to the number of points multiplied by the sample rate A frame is analogous to the sweep time of traditional oscilloscopes At the end of each frame the element reinitializes itself As a result there is a break between data frames This is not as important with the A D Demo element as with other elements The Number of Frames group allows you to specify how Snap Master will run the instrument When the Continuous option is selected the instrument will continuously acquire data frames until the user presses the Stop button To have the instrument acquire a specific number of data frames select the Stop After option and type the number of frames in the Stop After text field For example if Stop After is selected with a value of 5 Snap Master will acquire five frames of data and automatically stop the instrument The A D Demo element always outputs four channels of data numbered 0 through 3 Any selection made in the Channel List field is ignored The A D Demo element can output one of two types of waveform s
334. le allows you to make multiple selections by highlighting more than one cell at a time When you make multiple selections you are allowed to change parameters for more than one plot at one time The table only allows you to select columns that make sense For example you can select multiple Channel selections but you cannot select the Plot Type and Channel column Use the mouse to click and drag the selections you want or use with the CTRL key to make discontinuous selections Column Description Indicates the plot number used for DDE communication with the Display element Refer to Appendix D for more information Page Specifies the Display Page on which this plot appears The N option means the plot is not shown Linked Specifies the linked zoom group for the plot When the plot is included in a link group and you zoom in on one of the plots included in the group all plots zoom in to the same settings Up to 8 zoom groups can be defined Title Allows you to type your own title for a plot Press the F2 key to edit the title On Specifies the title used in the plot D means the Default Title is used U shows the User Defined Title and N means that no title is shown Plot Type Specifies the type of plot being used If you assign a new plot type to channels with a different y axis basis for example changing the plot type to a Mag vs F with time domain channels specified a message appears asking if you want to cancel the chang
335. lect an axis in the Current Axis the Y axis settings change to the ones used for that axis The final step is to assign a channel to a specific axis using the Channel Settings dialog box Major Divisions Rotate Axis Allows you to turn the values on the Y axis sideways so they read Values vertically up the screen as opposed to horizontally across the screen Usually works best with True Type fonts Channel Settings r Options Line Color Line Style Thickness n B YAris fi z Show As C Label Number Esai Help Figure 3 5 Channel Settings Y vs T Channels The Channel Settings dialog sets the colors and line style of the channels within a plot If the plot type supports multiple Y axes this dialog also assigns each channel to an axis Channels The channels highlighted in the list are being edited in the Options group Line Color Specifies the color of line used for the selected channels Line Style Specifies the type of line used for the selected channels If you select a dotted style the dots may appear to be connected together due to the high resolution of plotting in Snap Master To make the different styles appear more distinct try changing the X axis Minimum and Maximum values Thickness Specifies the width of the line used for the selected channels Higher thickness values tend to slow the performance of the Display Y Axis If Multiple Y Axes is selected in the Y Axis Settings
336. lement in the Toolbox a pop up menu appears that lists which A D drivers are currently installed The A D Demo element is listed in this pop up menu because it uses the same icon The menu selection that has a check mark by it indicates which A D board will be placed in the instrument when the icon is dragged to the instrument window To change the selection click on the desired driver 3 Activate Pipe Mode with the button or select the Element menu Pipe Mode command 4 Connect the A D element to the Display element 5 Turn off Pipe Mode with the button or select the Element menu Pipe Mode command 6 Save the instrument with the button or select the File menu Save Instrument As command Save the instrument as ANALOG Page 8 14 Snap Master User s Manual Configuring the 1 Open the A D Settings by double clicking on the element A D Element A Device 1 A2D Settings Untitled icf x File Edit View Settings Device Help s e ere Sa T pn 5 Channel Active Factor Offset Min 000 0 000 Ej ED es 1 100 AT o Max Label Units 0 10 A0 EE Figure 8 12 A D Settings 2 Press the button or select the Settings menu Frame Settings command Frame Settings Pacing 4 r Frame Length Type Hardware j Duration s Sec Location Internal C External C of Points
337. list 8 Set the Window Width to 200 9 Press the Next Line button to create a new equation io oo FFT Equation Builder Line 5 Page 14 35 Frequency Domain Calculation Result Channel PO Category Function Cross Power Spectrum a General Cross Power Spectral Densit Hydraulic Coherence Electrical Coherent Output Power Mechanical Transfer Function ha Ch 1 Output DO Volts Ch 2 Input AD Volts Scaling Window Result Frame Settings Window Width 200 E points Start At Point Overlap points Spectral Resolution 0 2500 Hz I Include DC Component Type Parabolic arzen Poisson I Average Spectra Across 0 frames Rectangular Riemann v Partial Frame C Zero Extend Ignore Description Specifies the number of points analyzed by the function and the result is output after each width The Spectral Resolution is equal to the sample rate divided by the width lt lt Previous Line Cancel Help In the Result Channel text box type PO Select channel DO from the Ch 1 list Select channel AO from the Ch 2 list Set the Window Width to 200 Select Coherence Function from the Function list Press the OK button to close the FFT Equation Builder Next Line Figure 14 24 FFT Equation Builder Settings for Coherence Function Close the FFT equation table using the File menu Close Equations command
338. lose the On Screen Keypad 8 Click on the button The equal sign appears after RO in the equation line The next step is to select the Addition function and use the Function Builder to define or calculation 9 Double click on the Addition item in the Function list to open the Addition Function Builder Addition Calculation A0 fal Options lt Default Oversample gt Oversample Undersample Syntax argument argument2 Description Adds each point of argument and argument2 Cancel Help Figure 12 13 Function Builder for Addition 10 For the first argument on the left side press the button and click on channel AO 11 For the second argument on the right side press the button and click on channel Al This defines the two arguments required for the function If you forget to fill in both arguments you will not be allowed to exit the Function Builder using the OK button 12 Press the OK button to close the Function Builder When you return to the main Equation Builder notice that the text A0 A1 has been inserted automatically 13 Press the OK button to close the Equation Builder When you return to the equation table the equation is entered in the first row Equation Definition column Analysis and Frequency Analysis Page 12 31 Running the Instrument 14 Position the selection box in the first row Comments column Using the keyboard type Addition Sample then press ENTER The Comments c
339. ls State variables do not include the leading apostrophe which distinguishes them from data channels Unlike result channels you can perform some arithmetic on a state variable in the Command element The allowed operations are addition subtraction multiplication division and modulus 46 returns the remainder of the number divided by the divisor State variables can only be assigned integer values from constants or other state variables To initialize the starting value of a state variable use the Command Settings dialog If you do not initialize the state variable value it is automatically set to 0 when the instrument is started The following example illustrates the power of using a state variable Suppose you want to stop the current instrument the fifth time the value of channel AO exceeds 3 volts To perform this count you can use a state variable The statements would look like the following assume the initial value of our state variable PeakCount is 0 Command Page 13 5 If PeakCount lt 5 AND AO gt 3 Then PeakCount PeakCount 1 Else Stop End If Comparisons Before executing a series of actions the IF portion of the statement must be true The value of the IF statement which can only be either true or false is determined using comparative operators The available operators and their Command element symbol are as follows Symbol Comparison Description Equals The left variable has the same val
340. ltiple A D Devices Figure 8 16 shows an instrument that contains two A D devices a Display element and a Disk Out element For this example we will use different sampling rates and frame times for the A D elements overplot certain channels and only save data from one A D element button or select the File menu New Instrument 1 Create a new instrument with the command in the Snap Master workspace 2 Place two A D elements or the two input elements you want to use for this tutorial a Display element and a Disk Out element in the instrument If you do not have a second A D Board installed you can select the A D Demo element from the pop up menu When the second board is placed in the instrument it will address the same board as the first one What we need to do is change the slot assignment for the board 3 Open the second A D Board Settings dialog box select device 2 from the Device menu then press the OK button This changes the device number for the B element Notice that the text underneath the element changes to reflect device number 2 4 Activate Pipe Mode with the button or select the Element menu Pipe Mode command Page 8 18 Configuring the Input Elements Snap Master User s Manual 5 Connect the first A D element to the second A D element the second A D element to the Display element and the Display element to the Disk Out element Remember that data flows through elements so the data from th
341. lumns are listed in the Assignment table Ch Specifies the channel which the sensor is connected to The channel is expressed with the element letter and channel number Select the channel from the drop down list in the upper left corner of the table Only one channel may be assigned to each sensor and a channel may only be assigned once in the table Label Specifies a long name for the channel This label accompanies the default channel designation such as AO B4 etc This label is used for the default title in the Display element and is saved in data files ID The Sensor ID from the database Factor The multiplier for the channel to convert from Output units to engineering units Also known as the m term for the linear scaling equation mX b Offset The adder for the channel to convert from Output units to engineering units Also known as the b term for the linear scaling equation mX b Input Min The minimum value that the sensor can have as an input signal expressed in Eng Units Used to define the default Y axis minimum for the Display element Input Max The maximum value that the sensor can have as an input signal expressed in Eng Units Used to define the default Y axis maximum for the Display element Page 7 4 Eng Units Output Min Output Max Output Units Kind Type Next Cal Date 7 2 Sensor Menu Commands Snap Master User s Manual The engineering units for the sensor such as C PSI
342. m Resources GDI 41 User 59 Video Resolution 1024x768 256 Colors Math Co processor Present DMA Buffer 192kB Help Figure 2 10 About Snap Master Dialog Box The About Snap Master dialog box provides important information about the libraries loaded by Snap Master and the configuration of your computer This information is important to know when calling for technical support so please be prepared to provide this information HINT To make a screen copy of this dialog box or any window hold down the ALT key and press PRINT SCREEN You can then paste the image as a picture in other applications such as a Word processor or graphics program If you want to copy the complete list of libraries and version numbers to the Clipboard as text double click in the version list box The building blocks of a Snap Master instrument are the elements which represent a specific piece of hardware or a software process When you combine elements into an instrument you have a customized setup that gives you maximum control over each facet of a test setup Each element can be classified as either an Input Element an Analysis Element or an Output Element An Input Element brings newly acquired or previously stored data into the instrument An Analysis Element processes the data to extract specific information as defined by the user Output Elements allow you to store and view the data or send data to external equipment Inp
343. m Support group provides modem support for remote instruments connected to a Hayes compatible modem When the Dial button is pressed Snap Master sends a modem initialization string ATZEOV1 S0 0 r n and dial command string ATDTphonenumber r n Once a connection has been established the element works as usual When acquisition has been completed the modem connection should be closed by pressing the Hang up button which sends the hand up command string ATH r n to the modem If the Hang up command is not issued the serial port will remain open and unavailable for use to other applications even after closing Snap Master Phone Number Specifies the phone number to be dialed with the Dial button Modem Timeout Specifies the amount of time in seconds Snap Master waits for a connection carrier detect before failing the Dial command Note that this check is done in hardware by checking the status of the Carrier Detect pin pin eight on a 25 pin connector pin 1 on a 9 pin connector If you are not using a modem to make a dial up connection set this value to 0 or you will receive timeout error messages 10 2 Tutorial Writing Example RS 232 Strings The Hydra Data Logger by John Fluke Manufacturing is an external piece of equipment which communicates over RS 232 This equipment can be configured to return a single channel of data in response to a query string To accomplish the task of returning the data from channel 0 on the Hydra the
344. m and the discrete Fourier Transform properly called a DFT commonly called an FFT The analog Fourier Transform produces a continuous waveform where all possible frequencies are represented with zero side lobe interference In the discrete world of the computer the DFT is inherently less accurate than its analog counterpart The DFT only allows a finite number of frequencies to be calculated for which introduces some error The purpose of the windowing functions is to approximate the result of an analog Fourier Transform using discrete data and the selection of a window type depends on a wide variety of factors This discussion is intended to give you an understanding of the practical results of using a DFT to help you select the best window type and width for your data When performing a calculation in the frequency domain the choice of window type affects the magnitude and accuracy of the result To maximize the accuracy a scaling window is applied to the original signal to obtain a new but related time function Page 14 12 Selecting A Window Type Snap Master User s Manual In addition to the input signal the window width also has an effect on the selection of the window type The window width affects the number of spectral lines the frequency resolution of the calculation which is equal to the sample rate of the input channel divided by the window width as well as the start and end points of the data in the window they should be eq
345. manuals are designed to provide answers to the questions most commonly asked about the program If you have access to the World Wide Web check out Attp www hemdata com which contains a section with Application Notes with advanced uses of Snap Master as well special hints and tricks If you purchased the software directly from HEM Data you may call our Technical Support Staff at 248 559 5607 Technical Support hours are between 8 00 AM and 5 00 PM Eastern Time Zone Or you can fax us your questions 24 hours a day at 248 559 8008 Faxing technical support questions is preferred since it is an efficient way to define and illustrate situations or problems This also allows the support staff time to research the problem before contacting you with solutions If you purchased the software through a third party contact them directly for technical support Page 1 4 When You Call For Support What Is Technical Support Snap Master User s Manual Please register your software before calling for technical support You may be asked to fax in your registration card if you have not already registered The amount of information needed depends upon the complexity of your question Minimal information generally required for efficient technical support includes e Version and build numbers from the Help menu About Snap Master dialog box or the Snap Master installation disks e System information from the Help menu About Snap Master dialo
346. mat Comments Plot Ch Channel string replace Ch with Ch1 Ch2 etc valid channel Plot Ch ChannelColor string RGB values separated by commas Plot Ch LineStyle integer item selected in combo list Plot Ch Thickness integer Plot Ch Y AxisNumber integer Plot Ch ShowAs string Label Number Channel Settings Single Value Plots Topic Item Exec Req Poke Format Comments Plot Ch NumColors integer 1 2 or 3 valid for DigitalMeter Indicator DialMeter plots Plot Ch ColorOneMin single Plot Ch ColorOneMax single Plot Ch ColorOneValueColor string RGB values separated by commas Dial Meter set Needle color Plot Ch ColorOneBkgndColor string RGB values separated by commas Dial Meter set Dial color Plot Ch ColorTwoMin single Plot Ch ColorTwoMax single Plot Ch ColorTwoValueColor string RGB values separated by commas Dial Meter set Needle color Plot Ch ColorTwoBkgndColor string RGB values separated by commas Dial Meter set Dial color DDE Commands and Parameters Topic Item Exec instrument Plot Ch ColorThreeMin instrument Plot Ch ColorThreeMax instrument Plot Ch ColorThree ValueColor instrument Plot Ch ColorThreeBkgndColor instrument Plot Ch DigitalMeterFormat instrument Plot Ch DigitalMeterDigits instrument Plot Ch BarMeterDirection instrument Plot Ch BarMeterPictureStyle instrument Plot Ch DialMeterStartAngle instrument Plot Ch
347. me Calculation Type Sum Continuously sums each point in the frame until the number of frames specified have been processed at which time the calculation restarts Average Continuously averages each point in the frame until the number of frames specified have been processed at which time the calculation restarts Output Every Specifies the rate at which a frame is output from the Multiple Frame element A value of 1 means that a result is produced every frame For large calculations you can reduce the number of output frames by raising this number The Output Every n frames value must be less than the number of frames that are operated on as specified in the Frame Calculation Type group 15 10 Tutorial MultiFrame Building the Instrument This tutorial shows how to add five frames of data and output the result as either a single frame of data or as five separate frames R D A D Demo B MultiFrame C Display Figure 15 34 Instrument for MultiFrame Tutorial 1 Create a new instrument with the button or select the File menu New Instrument command in the Snap Master workspace 2 Place the A D Demo MultiFrame and Display elements in the instrument Utility Elements Page 15 23 3 Activate Pipe Mode with the button or select the Element menu Pipe Mode command 4 Connect the A D Demo element to the MultiFrame element and the MultiFrame element to the Display element 5 Turn off Pipe Mode with the button or select
348. ments Date 11 10 1997 Time 12 10 02 Internal Pacer 00 Hz Figure 4 5 Read File Comments The File Comments button allows the user to read the file comments stored in the data The File Comments can only be read from native Snap Master file formats and are not editable from this dialog box The Print button sends the information from the Comments section of the header to the default printer File Information Data File Info p Header Information Data Info Board Type Demo A D Date 05 07 1992 Time 17 13 08 Clock Type Internal 2 A Trigger Type Free Running File Format Standard Binary Resolution 16 Bit tt of Channels 4 Data Scaled _ Dala Type Time WaveForm Sine SES IEEE Channel Information Total it of Points 800 Channel A0 __ Voltage 1t Pre Trigger Points 0 Units Volts Frequency 100 Conversion 0 1x Frame Length 8 Minimum 10 Clock Units Sec Maximum 10 w Figure 4 6 Data File Info The File Info button shows detailed information about the data file from the file header This command is only be available when a native Snap Master data file is selected The Data File lists the SM files associated with the DAT file specified in the File Name The Header Information Frame Information and Data Info shows the parameters that apply to the entire data file The Channel Information shows the available channels along with any channel specific information Page 4 8 Snap Maste
349. ments piped after the Relay might not process their data new result frames will not be produced and the instrument can only be stopped manually In these cases you will need to restructure your instrument so all Analysis processing occurs before the Relay element and the Relay passes only the results Page 15 2 Snap Master User s Manual Auto Toggle Settings Configuration The Driving Channel setting for this element determines which channels with a given letter description are available for the Channel list When you select a driving channel all channels using the same element letter can activated using this element To automatically switch channels from more than one element letter such as more than one A D element you will need to use multiple Relay elements or combine the elements into one element letter using Analysis Frame Settings The output channels from the Relay element has their own frame characteristics but the Frame Settings are based upon those of the Driving Channel The Sample Rate is always the same as the Driving Channel s sample rate but the Duration of the frame can be changed This allows you to operate on smaller sections of data than the entire frame To use the same frame duration as the Driving Channel select the Use Defaults checkbox To create sub frames turn off the Use Defaults check box and enter either the new Duration or of Points If the Driving Channel reaches the end of its frame before t
350. mes must be enclosed in quotation marks If the Time or Frequency channel is saved then it will be the first column in the data file Whether or not the Time Channel is included in the data file is specified by the Save Time Channel checkbox in the Disk Out dialog box For frequency domain data each data point is a set of two floating point numbers separated by a space the magnitude part and the phase part If the Time channel is saved then the frequencies in Hertz are written to the file VLIIME Sec CHO CHL CH2 CHS 0 000000 5 000 0 0000 0 0000 0 0000 0 02000 4 990 0 0197 0 0000 0 0000 0 04000 4 961 0 0785 0 0000 0 0000 0 06000 4 912 0 1754 0 0000 0 0000 0 08000 4 843 0 3089 0 0000 0 0000 0 10000 4 756 0 4770 0 0000 0 0000 0 12000 4 649 0 6769 0 0000 0 0000 0 14000 4 525 0 9056 0 0000 0 0000 etc Page 4 22 Binary Plotter Data File Format Snap Master User s Manual Binary Plotter data files are similar to the ASCII Plotter format except that the data values are stored as interleaved binary floating point numbers As with the ASCII Plotter format the first line contains header information and raw data begins on the second line HEADER File Offset 0 bytes Length 4 Channels bytes Header End HE 4 st Channels 1 Note If only one channel is contained in the data file then the header ends after byte 3 Byte Bit Range Description Assignment 0 b7 bO File Type OxCC 1 b7 b5 Reserved X
351. ming Method C Date And Time ceu C Numbered Sequence File Seed ss TER Ordinary Auto Overwrite File Name Directories Help fonechdat eNsmMefuser 52110282 dat a exe Save Options 62511152 dat C3 sm File Comments batch000 dat batch001 dat E defuser batch002 dat capture dat Disk Out Defaults examb1 dat aA junk dat Throughput Tester File Format Drives Standard Binary dat c hardly E Network ASCII File Export Number Format C Decimal 6 4 Volts F Saye Time Freq Channel Scientific xX 4 esXXVolts C Engineering ox 4 kVolts Figure 8 20 Disk Out Settings 2 Save the data file using the Ordinary naming method and set the File Name to ONECH 3 Press the Save Options button Disk Out Save Options Channel List r Frame List Save All Channels Iv Save All Frames Frame yO Add Tio List pere romae From List Le Cancel Hel Figure 8 21 Disk Out Save Options 4 Turn off the Save All Channels check box The Save AII Channels check box automatically selects all available channels for storage to disk By turning the check box off you can write specific channels to disk Disk Out only saves data from the channels that are highlighted in the channel list 5 Highlight the BO channel in the Channel List 6 Press the OK button to close the Save Options dialog then press the OK button to close the Disk Out Se
352. mining Frame Characteristics To illustrate how frame characteristics are determined for the Analysis element assume that element A has 100 points per frame and a frame length of 1 second a sample rate of 100 Hz Also assume that element D has 400 points per frame and a frame length of 2 seconds a sample rate is 200 Hz The equation table in the Analysis element has the following equations Run Comments I Equation Definition Label Units RO AO i D X a E TO 40 DO G0 block 10 A0 uini The simplest equation is shown in line 1 RO AO The output of the equal function is an array with the same number of points per frame as element AO The result element letter R inherits the frame characteristics of element A so all subsequent uses of element letter R will have a sample rate of 100 Hz and a frame length of 100 points per frame Element letter R would have the same frame characteristics for other array functions using only element letter A such as RO A0 Al RO cos AO0 etc Channel SO is defined as the average of channel AO In this case the Average function produces a single point so element letter S has a frame length of one point Any other equations using element letter S also have a frame length of one point As a result if you define an equation later in the table as S1 AO A1 you will only see the result of the first data point b
353. mmand AO vs Time BO vs Time Time Sec Time Sec If all is well the Display window opens and begins plotting both the output of the A D Demo as well as the same signal from the A D hardware Notice that after two seconds the signal on the A D hardware channel goes to 0 This is because the A D Demo has finished its frame and produces no more data and the Inactive State of the D A channel is 0 If the test does not go as expected make sure you have the proper signal connections and software settings If the Status Log appears with an ERROR entry follow the remedy listed If all else fails verify the hardware Configuration 11 4 Tutorial Outputting Digital Data Outputting data with the Digital Out element uses the same steps as sending data out using an D A element Let s use a similar approach as before this time without reacquiring the data For a digital signal try connecting the Digital Output to an LED or meter to indicate digital high on and low off Building the Instrument AND DIGOUT 47D Demo B Digital Qut Figure 11 8 Instrument for Digital Output Tutorial 1 Create a new instrument with the button or select the File menu New Instrument command in the Snap Master workspace 2 Place an A D Demo element and a Digital Out element in the instrument 3 Activate Pipe Mode with the button or select the Element menu Pipe Mode command 4 Conne
354. moothing filter If you set a shorter rise time you will see less effect at higher frequencies because the amount of transition within the moving average window or the Rise Time setting is less so the averaging does not cancel out as much information Utility Elements 15 7 Histogram ath Page 15 17 This element is included with both the Waveform Analyzer and Frequency Analyzer Modules The Histogram element counts the number of instances a specified event occurs The element can count events occurring in either the X or Y axis In addition the element also sorts data into bands bins intervals or ranges this text uses the term bins to represent all of these terms The main uses for the element include histograms and band analysis Histogram Settings Input Channel Output Type Type Time C Band Analysis X Axis C Erequency Spacing Linear A Channel A0 Histogram Y Axis Calculation Output Bins C Sum Values Of All Bin Events C Bin Width 2 Voile C Average Values Of All Bin Events H of Bins po Count Bin Events Minimum po Volts Threshold 5 Volts Maximum o Volts Cancel Help Figure 15 26 Histogram Settings Dialog Box When you calculate a new channel with this element the output is channel 0 using the element letter of the Histogram element When the channel is plotted with the Display element the Histogram plot type is
355. n Builder Settings for Forward FFT 3 In the Result Channel text box type FO 4 Select channel AO from the Ch 1 list 5 In the Window Width text box type 200 If you enter an invalid Window Width a message box appears asking you to select a valid width The closest values to the one you entered are listed According to our rules for window width we must try to match the start and end points of the data within the window width Channel 0 of the A D Demo contains a 0 5 Hz cosine wave At 100 Hz the waveform will repeat every 2 seconds so four seconds contains two periods Therefore because the start and end points are the same and we are capturing 2 complete periods of the waveform our results will be good Our frequency resolution is also good which is equal to 50 Hz 200 points a spectral line every 0 25 Hz 6 Press the OK button to close the FFT Equation Builder When you return to the FFT equation table the settings from the Equation Builder are entered in the first row of the table which is where the selection box is 7 Close the FFT equation table using the File menu Close Equations command 8 Save the instrument with the button or with the File menu Save command FFT Running The Instrument Page 14 29 E Display Page 1 Bee Eile Edit View Settings Start Layout Cursor Help LO Drar EJ alae b AO Nolts Time Sec F
356. n Note 140 4 Digital Auto Power Spectrum Measurements Hewlett Packard Application Note 243 The Fundamentals of Signal Analysis February 1985 Microsoft Visual Basic Programmer s Guide Microsoft Corporation Redmond Washington 1991 Microsoft Windows Resource Kit For Operating System Version 3 1 Microsoft Corporation Redmond Washington 1992 Mitchell John S An Introduction to Machinery Analysis and Monitoring Penwell Books 1981 MOS Microprocessors and Peripherals 1987 1988 Data Book Advanced Micro Devices 1987 Oppenheim Alan V ed Applications of Digital Signal Processing Prentice Hall Inc Englewood Cliffs New Jersey 1978 Potter R W Compilation of Time Windows and Shapes for Fourier Analysis Hewlett Packard Palo Alto Calif 1970 Ramirez Robert W The FFT Fundamentals and Concepts Prentice Hall Inc Englewood Cliffs New Jersey 1985 Roberts Richard A and Mullis Clifford T Digital Signal Processing Addison Wesley Publishing Company Reading Massachusetts 1987 Talor James L Computer Based Data Acquisition Systems Instrument Society of America Research Triangle Park North Carolina 1986 Tompkins W J and Webster J G Design of Microcomputer Based Medical Instrumentation Prentice Hall Inc Englewood Cliffs New Jersey 1981 Aliasing Page C 1 Appendix C Aliasing Aliasing is a phenomenon that occurs where high frequency components are shifted to a lower frequency which pr
357. n and before the function arguments If an options is not specified the default option set in the Analysis Options dialog is used User defined functions provide an easy way to create your own function for use in the Analysis element equation table Function definitions look similar to equations except that e User defined functions must appear at the top of the equation table before they are referenced in any equation e A user defined function always begins with the keyword Define followed by the name of the function e User defined function names and function arguments can only contain alphabetic characters no numbers allowed and must not match any of the intrinsic function names built in to the Analysis element e After the function name the arguments for the function are enclosed in parentheses and separated by commas If the function does not contain any arguments such as when defining a constant you must include the parentheses in the function definition e The function arguments are followed by an equal sign and the definition of the function All function arguments must be included in the function definition Page 12 28 Common Functions Snap Master User s Manual The following is a list of commonly used functions in the Analysis element Enter these at the top of the equation table before using the function in an equation All definitions should be on one line any line breaks shown here are only to accommodate t
358. n eese eee eee ee eee e esee een esee sns stesso ss ese ssss see sssesesoseeeessssess 3 9 13 4 Tutorial Subroutines and State Variables c eeee eee e eese eene eese eere e esee eene see sns esee sss sesose see sessesesseseseesess 13 12 13 5 Tutorial Automatically Starting Another Instrument ceeee eese e eese esee eene eee ena sees ens esses enses eseossesesssseseess 13 15 Page 13 1 The Command element allows the user to make decisions and perform actions based on data from other Snap Master elements such as an A D Board or the Analysis element Actions include setting the value of a Digital Out or D A element channel starting and stopping instruments and displaying messages Command Untitled File Edit View Settings Help Ejea gt a 3 I lox Run Equation Definition i Sub IncrementCount M 1 2 i PeakCount PeakCount 1 3i i LurrentPeak 1 4 Ls jEnd Sub 3 i 6 lE A0 4 5 Then rd df CurrentPeak 0 Then 8 IncrementCount 78 1 Endi DEAE eee lli LumenPesk 0 2 12 1 ENGI v 3 1 ER w 14 1 i PeakCount 3 Then baled satis ginaiaaatatn AASE AERE N 15 End If i 11 11 97 1021 40 AM Figure 13 1 Command Element Window The Command Bar buttons unique to the Command elemen
359. n is automatically placed in the File Name field and the current directory is scanned for files with that extension File Naming Method Date and Time Creates a data file based on the date and time when the instrument is started using the current month day hour minute and fraction of minute to name the file The month is indicated by a single number for the months January 1 through September 9 with October O November N and December D using the first letter in the month name The day year and minute use two digits each including any necessary leading zeroes For the fraction the minute is divided into 10 equal sections of six seconds each For example if you start the instrument at 11 32 30 AM on October 27 the data file will be named O2711305 DAT Disk I O Page 4 9 Save Options Numbered Creates a data file series by appending the File Seed with a sequence of Sequence numbers to create an eight character file name For example assume the File Seed is TEST The first time the instrument is run the first file created is called TESTOO00 DAT The next time the instrument is run the new data file is called TESTO001 DAT The next time the file is called TESTO002 DAT after that TESTO003 DAT and so on This allows the user to run the same test multiple times without creating a new file name for each run Ordinary Creates a data file using the File Name If the instrument is run and the file name specified in th
360. n on the left the Y axis scaling shown was achieved using the lal or Auto Scale button On the right the equivalent thermocouple data is shown in degrees C The scaling shown is the default range for the thermocouple type used When you are measuring actual thermocouples repeat the exercise replacing the A D Demo with an actual A D device Page 15 12 15 5 Smoothing e Table Columns Snap Master User s Manual This element is included with the Data Acquisition Module The Smoothing element provides a simple Low Pass averaging filter similar to the one found in the Analysis element For low level signals such as thermocouples which may be noisy the Smoothing element makes the data more presentable for display and storage purposes Smoothing Settings DrivingChannek A0 Voltage Smoothing Options zx Yes 4 Result Active Figure 15 17 Smoothing Settings The Driving Channel setting determines which channels are available for the Input Channel table selection When you select a driving channel all channels using the same element letter can be smoothed using this element To smooth channels from more than one element letter such as more than one A D element you will need to use multiple Smoothing elements In the Smoothing Settings table you can edit any column except the Result Channel and Process columns which display their column headings in red The following c
361. n selected the Display clears the plot window each time a new frame begins If you want to overplot the contents of multiple frames turn off the Auto Clear check box When Auto Clear is turned off the plot mode is Stationary so only the data in the range set by the Minimum and Maximum is shown Defines where the X axis is drawn relative to the Y axis By default the X axis 1s drawn so it crosses the Y axis at Y 0 Y Min draws the X axis at the bottom of the plot with the values and ticks below the axis Y Max draws the X axis at the top of the plot with the values and ticks above the axis None means the X axis is not drawn at all If your Y axis range does not include 0 you may see tick marks extending beyond the plot boundaries especially if the Axis Location is set to Y 0 To correct this select a different Axis Location Sets the times displayed in the plot and the format of the axis labels Default Scale Minimum Maximum Format When selected the Minimum and Maximum settings are configured to show the entire data frame for the first channel defined in the Display Layout Sets the start and end time for the X axis Remember that for Moving mode the difference between the Maximum and Minimum is used to set the increment amount Specifies how the time labels are displayed The Default Scientific 1 00e 03 Engineering 1K and Fixed 1000 000 formats display the relative frame time along the axis Significant Di
362. n the A D Demo element icon in the instrument Page 2 22 Changing the Frame Length Stopping the Instrument Automatically Running the Instrument Snap Master User s Manual 3 Double click in the Sample Rate field to highlight the current value then type 50 The Sample Rate of the A D Demo element defines how many times per second a sample is taken In other words the sampling rate represents the number of data points per second for your instrument In addition to the Sample Rate we can specify the length of each data frame in either seconds or as the number of points For normal sampling with Time as the X axis the number of points per frame equals the sample rate multiplied with the frame length in seconds For this example we will specify the length using the time field 1 Select the Duration radio button in the Frame Length group 2 Double click in the Duration field to highlight the current value and enter 5 This setting makes each frame five seconds long If you select another item in the dialog either by clicking on it or by pressing TAB notice that the of Points entry is automatically recalculated In the previous example you had to manually stop the instrument using the Stop button or menu command This section will automatically stop the instrument after three frames of data have been processed 1 Select the Stop After radio button in the Number of Frames group 2 Double click in the Stop After field to h
363. n the Registration Card as directed Along with information on your software use and needs the data you provide helps us to serve you more efficiently if you require technical support Please be sure to read the Software License Agreement for any warranty and disclaimer information regarding the use of this product Unless otherwise warranted by your vendor registering your software entitles you to basic customer support coverage of e Free telephone support for four 4 months from date of purchase duration of support period may vary according to whom you purchased this product from e Free product upgrades for thirty 30 days from date of purchase An Extended Support Program ESP for continued technical support and software upgrades can be purchased after the standard support policy expires Please contact an HEM Data sales representative for more information If you purchased the software from a third party reseller your Customer Support terms including extended support may differ Please contact the company you purchased the software from for further information HEM Data reserves the right to withhold customer support service at any time from unregistered users or from anyone who abuses the service We also reserve the right to change the support fee structure support policies and procedures without notice To save time please refer to the applicable software and hardware documentation before calling technical support Our
364. nap Master User s Manual The first time you make a connection to an IndustrialSQL database you are asked to verify the ODBC settings You should only enter or modify the Network Address all other settings for the ODBC DSN Data Source Name are created automatically Nanok tusr I Mur Traxted Connection Figure 16 2 ODBC Settings for Snap Master to IndustrialSQL DSN 16 2 IndustrialSQL In Settings IndustrialSQL In Settings Statt Time 11 13 1997 10 00 00 zl End Time 11 13 1997 10 05 00 v Resolution 1000 ms All Groups All Analog Tags Active Tags CERE Fae Fe E Toe GA System Objects lA cid am ies Tags EA SysActivellsers m Al Discrete Tags EA SysCrtEwCnt eG allSting Tags JE SysDateDay GQ AllEvent Tags JE SysDateMonth 1 9 InTouch Nodes EA SysDateYear a System Status Tags JEA SysEnEmCnt mi H Private Groups E SysEmorRate E SysFatalEnCnt EA SyslODriverBytes E SyslODriverCPS i SysMinutesRun Ei E SysSpaceAlt AO SysMinutesRun zi Remove Current Tag Remove All Tags Cancel Hep Figure 16 3 IndustrialSQL In Settings The IndustrialSQL In Settings dialog specifies which tags are activated for use by Snap Master The format and usage of this dialog is similar to the IndustrialSQL Trend program except that instead of dragging tags to a trend plot you double click to send them to the Active Tags table Before using this element you must install the IndustrialSQL Server and
365. nap Master s standard file format at least two files are created a DAT file and one SM file for every element saving data The actual data including headers is stored in the SM files and the DAT file acts as a pointer to all SM files with the same file prefix The last letter in the file extension must correspond with the element letter in the CHANS array for proper operation All SM files consist of two major sections the file header and the data frames The file header defines the parameters used in the data file and the values for these parameters Each frame of data consists of two parts the frame header and the raw data The beginning of a new frame header is specified by a TR followed by the frame number The next line contains a date and time stamp for the start of the frame Section Contains File Header Introduction Parameter Name and Value List Data Frame Frame Header Data Data Frame Frame Header Data Data Frame Frame Header Data etc for the remaining frames Some important items to note when writing a Snap Master data file e Spaces are ignored when reading the data file except after an equal sign 2 that defines a numerical value where there must be no spaces e Snap Master only understands its own internally declared parameters The file header contains information used by Snap Master to determine the parameters applicable to all data frames contained in the file If the data file does not corre
366. nate EGA VGA adapter 2D0 to 2DF Alternate EGA VGA adapter 2E0 to 2EF Serial port COM4 2E0 to 2E7 not used 2F0 to 2FF Serial port COM2 2F0 to 2F7 Reserved 300 to 31F Prototype or network board 310 to 31F Prototype or network board 320 to 32F 330 to 33F 340 to 34F 350 to 35F 360 to 36F PC network 370 to 37F Parallel port LPT1 370 to 377 not used 380 to 38F SDLC Bisynchronous communications secondary 390 to 39F Cluster 394 to 39F not used 3A0 to 3AF Bisynchronous communications primary 3B0 to 3BF Monochrome display and printer adapter 3C0 to 3CF EGA VGA adapter 3D0 to 3DF CGA MCGA adapter 3E0 to 3EF Serial port COM3 3E0 to 3E7 not used 3F0 to 3FF Floppy disk 3FO to 3F7 Serial port COMI 3F8 to 3FF Index Page X 1 Appendix X Index Overlap 12 24 Block Mode 6 11 6 17 Block Size 3 22 B Bode Plots 3 7 386MAX 1 6 Bohman Window 14 17 Boolean Operators And 12 18 2 Not 12 19 9513 Chip 9 14 Or 12 18 Xor 12 19 13 6 13 7 Buffer Retrace 3 22 A Buffers 1 7 2 8 3 22 A D 2 11 Bulk Modulus 14 10 A D Demo 2 20 A D Device 8 1 8 13 8 17 11 4 C A D Overrun 8 11 About Snap Master 1 6 2 2 2 10 Cache 1 8 Absolute 12 13 Cauchy Window 14 17 Addition 12 12 Channel Settings 3 8 3 24 3 28 Admittance 14 10 CIC 15 8 Aggregate Sampling Rate 8 5 Clipboard 3 17 6 1 6 9 Aliasing 3 4 Clipbook 6 1 6 19 Analog Input 8 1 Coherence 14 8 14 36 Analog Output 11 1 Coherent Output Power 1
367. ncate Modulus Channel Information fir order type f1 f2 window arg1 iir order type f1 f2 family p1 p2 argl time time Zpts dur time arg1 z pts argl range format start stop arg1 block format pts overlap arg1 frac arg1 round arg1 trunc arg1 arg mod arg2 info type arg1 order 1 to 400 type 1 Low Pass f1 h High Pass f1 p Band Pass f1 f2 r Band Reject f1 f2 fl cutoff frequency 1 f2 cutoff frequency 2 window M Hamming N Hann B Blackman Harris K Kaiser Bessel R Rectangular order 1 to 400 type 1 Low Pass f1 h High Pass f1 p Band Pass f1 f2 r Band Reject f1 f2 cutoff frequency 1 cutoff frequency 2 b Butterworth t Chebyshev p1 e Elliptic pl p2 i Inverse Chebyshev p2 Pass Band Ripple in dB Stop Band Ripple in dB pts points per frame dur frame length in seconds produces current time of frame pts points to shift positive or negative format optional p Points t Time start start point stop stop point array values 0 outside of range format optional p Points t Time pts size of block overlap optional amt of overlap fractional portion only rounded integer integer portion only 0 Oversampling ul Undersampling remainder portion of division Time Domain s Sample Rate pl Frame Duration in Points t Frame Duration in Seconds Frequency Domain s Resolut
368. nclude applications programming of Snap Master via DDE The Snap Master Front Panel Library provides example source code for developing custom programs and it carries a separate support policy Please contact HEM Data for more information on this and other programming tool kits for Snap Master Execute DDE Commands are sent by the client application to the server using the DDE Execute method The Service Name and Topic strings are separated by a vertical bar ANSI character 124 or SHIFT on an extended keyboard and the Topic and Item strings are separated by an exclamation point The format of a DDE Command is as follows Service Name Snap Master Topic Name Instrument Name Item Name ElementLetter ExecuteCommand Data If any data accompanies the command a comma and the data are appended to the Item In the tables listing the available commands the data column specifies the data that must be sent with the command If there is no data specified then the comma and data are not sent The following examples illustrate a DDE Execute without data and a DDE Execute with data Assume that the instrument name is TEST INS and the Sensor is element letter A Without Snap Master l TEST INS A FileNew With Snap Master TEST INS A FileOpen C SM NEXT ASN Page D 2 Snap Master User s Manual Request For a DDE Request the client application asks the server what the current value of the DDE Item is This text is always returned as a stri
369. nction directly into the Range parameters using the Quick Function button 14 Press the OK button to close the Range Function Builder 15 Press the OK button to close the Integration Function Builder and return to the Equation Builder 16 Press the OK button to close the Equation Builder 17 Position the selection box in the fourth row Comments column Using the keyboard type Integrate Over A Range then press ENTER 18 Position the selection box in the fourth row Label column Using the keyboard type Area then press ENTER 19 Position the selection box in the fourth row Units column Using the keyboard type Volts then press ENTER 20 Switch to the main Snap Master window and save the instrument using the button or the File menu Save Instrument command G Display Page 4 Beles Eile Edit View Settings Start Layout Cursor Help 9 ceterae AQ vs Time Area vs Time A0 Volts o Time Sec Time Sec 11 11 57 Figure 12 29 Display Window with Integration Over A Range When you Start the instrument you should see the results shown This Display window shows a Y T plot for AO and R1 Notice that the integration does not begin until the value of AO goes below 0 volts and stops second after that the sample rate for AO is 100 Hz so 100 points is equal to 1 second If you want to see the signal being integrat
370. nd save the instrument as CONSTART using the File menu Save Instrument As command Running The When you start the CONSTART instrument you see the same results from our last tutorial Instrument However when the third peak is found a new Display window opens showing us data from the CONSTORE instrument Remember that by default the Disk Out element uses the Date amp Time file name so you have a new Standard Binary data file in the DEFUSER subdirectory with the current date and time as the file name FFT Page 14 1 Chapter 14 FFT 14 1 Menu Commannds ssscccssssscssccsccssscccccsssccescsscsccsssscscssssccscsssscsssssscccesssscssssssscssssssccsssssscssssssccsssssscssssssscssessscssees 14173 14 2 Functions iret oes re ore EVER ENS E VEN ENS RUE SEEN USER ES EN UK LENS ER RS N NUR EVO RN SUR ERA ESTA Ee a UNES Ee NN EUER Fes eV vau eas aaa ves sevevseseres 4 0 14 3 Window Types 1 1 ee ceres esee eene ee eterne esee enses ee ens eset enses sets asses senos ses bisako senso see soss sapori siseses suoran caions sesoses La 11 14 4 inmvinim e pP LA 2A 14 5 Tutorial Performing a Forward FFT eeeeeeeee sees eese sees eee etes seen s teens sess sess se eens cesse se sssesesseessseesseeesees 14 26 14 6 Tutorial Performing an Inverse FFT 1 eeeee esee eese eene eese eee een esee en esses osse ense sesso sesso soseseesessesesseseseesssss 1
371. nductor storage Items followed by an exclamation point in the title bar When selected these command buttons immediately initiate an action In contrast menus must be pulled down and an option selected before an action is initiated Menus allow access to Snap Master functions commands and options Once you select a menu you can then select the command you want from the menu If a menu item is grayed its action is not appropriate at that time Some menu items are used to indicate a system state such as on or off in which case a check mark is used to indicate the current state Microsoft Windows is a graphically based user interface for PC compatible computers Windows allows you to run more than one application at a time and transfer information between applications Snap Master is a true Windows application and operates in the Windows environment Button located in the upper right corner of the window to the left of the Maximize Box If the button exists it will contain a down arrow Clicking on the Minimize Box shrinks the window to its associated icon and sends the icon to the bottom of the screen By double clicking on the icon the window will be restored to its previous size and location A set of semiconductors or electromechanical switches with a common output that can select one of a number of input signals The characteristic of an operating system that allows a processor to perform several operations at once Windows is a
372. ne followed by the function name and arguments an equal sign and the function definition Although it is not required the text in this manual always capitalizes element letters and uses lower case letters for functions This is also how the Equation and Function Builders construct equations We recommend that you use this same form when entering your own equations for improved readability Analysis and Frequency Analysis Page 12 27 Equation Format User Defined Functions The Enhanced Syntax uses an intuitive approach to writing equations If you are having problems creating an equation try using the Equation Builder to get started Note These rules apply only when using the Enhanced Syntax option For information on writing equations using the Original Syntax please refer to the online help file e Equations always begin by defining the result channel specified as element letter and channel number e All result element letters inherit frame characteristics number of points per frame and duration based on the function used by the first equation which creates the result element letter e The result channel is followed by an equal sign and the calculation being performed e Function arguments are always enclosed inside parentheses and appear after the function and any parameters and options Arguments may contain nested functions e Function parameters and options are always enclosed in brackets immediately after the functio
373. nes The left most pane shows the overall tree view groups When you select an object in the left pane of the tree view all objects lower in the namespace hierarchy will appear in the right pane leaves To search for a tag in the right pane of the tree view type the tagname in the Filter Mask box As you type the desired tagname tags starting with the letters you have typed will immediately appear in the tree view The tree view displays all objects that are visible to all clients This grouping is also called the public namespace You can navigate in the tree view as you would any typical Windows based browsing application Page 16 4 Active Tags Snap Master User s Manual The tag list displays information about all tags included from the database and their status in Snap Master To include a tag in the instrument double click on an item in the tree view The tag is then added to the end of the list and a new channel is created If you remove a tag from the Active Tag list using the Remove Current Tag button the channel numbers are renumbered to always be contiguous If you are using a specific tag as a channel in downstream elements such as Analysis or Display you will need to manually change those elements to reflect the change in the tag to channel numbering The table columns in the Active Tags table are Channel Specifies the Snap Master channel designation for the tag Name Specifies the tag name of the channel T
374. ng and the following tables list what type of information is returned by Snap Master The Service Name and Topic strings are separated by a vertical bar ANSI character 124 or SHIFT on an extended keyboard and the Topic and Item strings are separated by an exclamation point The format of a DDE Request is as follows Service Name Snap Master Topic Name Instrument Name Item Name ElementLetter RequestItem The following examples illustrate three DDE Requests to the A D Demo element one that returns a number one that returns a string and one that returns a predefined answer Assume that the instrument name is TEST INS and the A D Demo is element letter A Number Snap Master l TEST INS A SampleRate Returns 100 String Snap Master l TEST INS A Units Returns Secs Answer Snap Master TEST INS A Continuous Returns YES Poke For a DDE Poke the client application tells the server the new value of the DDE Item This text is always sent as a string and the following tables list what type of information Snap Master is expecting The Service Name and Topic strings are separated by a vertical bar ANSI character 124 or SHIFT on an extended keyboard and the Topic and Item strings are separated by an exclamation point The format of a DDE Poke is as follows Service Name Snap Master Topic Name Instrument Name Item Name ElementLetter PokeItem New Value The following examples illustrates three DDE Pokes to
375. ng the commands and parameters over DDE If you are interested in creating your own custom user interface refer to Appendix D or contact HEM Data for the availability of the DDE Programmer s Toolkit to help develop your application Finally we come to the actual data acquired from or calculated by the Snap Master elements There are many reasons to transfer data out of Snap Master because of the many features offered in other applications For example the user may need to store a special value in a central database or perform report generation Many of these and other specialized needs are better met by a dedicated program which is why Snap Master has the capability to share data with other programs In Snap Master data can be further categorized into two types channel data and Cursor Marker data Channel data is generated by the input and analysis elements and is transferred using the DDE out element This includes data from A D Boards the Analysis element and others The Cursor and Marker data come from the Cursor Data table in the Display element which can be transferred over DDE to other applications The following table summarizes the DDE conversations supported by Snap Master Info Type Direction S M Method S M Role Link Parameters In Main S M Server Cold Commands In Main S M Server Cold Acquired Out DDE Out Server Hot Warm Calculated Cold Channels Cursor Marker Out Cursor Data Server Hot Values Table Warm Technically
376. ng the complete Sensor database From this table you can insert new sensors into the database modify the parameters for existing sensors and delete sensors from the database If you change the parameters and update the calibration date the data is stored in into the database and update the calibration history for each The table is sorted alphabetically by ID When inserting or editing a sensor the Automatically Calculate group determines which values Snap Master calculates for the Y mX b calculation The item selected can not be edited by the user because Snap Master is calculating the value for you When you have a sensor or transducer you usually know two sets of numbers either the Factor and Offset the Input Minimum and Maximum or the Output Minimum and Maximum Select the set you do not have in the Automatically Calculate group Sensor Database Page 7 5 The additional table columns available in the Specifications table are Model The manufacturer s model number for the sensor Kind The class of sensor such as pressure temperature etc Type The type of sensor such as thermocouple flow etc Manufacturer The name of the sensor manufacturer Serial Specifies the manufacturer s serial number of the sensor Freq Max The maximum input frequency for the sensor Last Cal Date The last date the sensor was calibrated The Next Cal Date is equal to the number of days specified in the Interval plus the Last Cal Date Cal Interv
377. ngs Hold Previous Value New Constant Value g Volts eese sena Figure 5 4 Constant Settings The Constant function produces a straight line waveform that maintains a specific value for the duration of the waveform stage This function is useful when defining the hold stages of a custom ramping waveform Hold Previous Value Uses the last data value from the previous stage for the duration of the current waveform stage New Constant Value Uses the specified value for the duration of the current waveform stage Sine Settings r Sine Parameters Frequency Constant 1 Hz ClimearSweep Initia THe C Log Sweep Final bj Hz Amplitude 10 Volts Rectify Damping Off Linear C Exponential Coefficient 2 DC Offset 0 Volts Phase fe Degrees Cancel Help Figure 5 5 Sine Settings The Cosine and Sine functions generate the traditional trigonometric waveform There are a number of settings to modify the resulting waveform including swept frequencies and damping Note To produce a Cosine wave from a Sine Wave the Phase is shifted by 90 Constant Specifies a single frequency for the duration of the waveform stage Linear Sweep Specifies a swept frequency from the Initial to the Final frequency The net frequency sweep occurs as a linear function of time for the stage length Log Sweep Specifies a swept frequency for the function from the Initial frequency to the Final frequency The net frequency swee
378. ning on this check box to automatically assign the channel names in the instrument When selected the Disk In element counts the number of CRLF Carriage Return Line Feeds to estimate the number of data points in the file Use this value to set up the points per frame by dividing the total number of points in the data file by the number of frames you wish to subdivide the data into Defines the sample rate for the data Required to set the frame characteristics Defines the time duration for each frame of data Required to set the frame characteristics Defines the number of points per frame of data Defines the duration for each frame of data Required to set the frame characteristics Specifes the default minimum value used by the Display element when configuring a plot Specifes the default maximum value used by the Display element when configuring a plot Replay Options r Frames Letter Re Mapping C All Frames LA T Frame Range Original Mapped Start At 3 Stop At 5 t Replay Mode E f C Conti E i c D H oich Pause After 1 frames p NN Iv Paced Replay 5x Actual v Slower Faster HN Speed jf em IM M I Ean Help Figure 4 3 Disk In Replay Options The Replay Options button is only available when replaying native Snap Master data files Using the different selections you can control how the file is replayed in the inst
379. nnels is separated by a comma Each collection of data points is separated by a CRLF Carriage Return Line Feed In most cases the first line in the file is the header which consists of the channel names for each of the channels stored in the file Each channel name is contained in quotation marks The remaining rows contain floating point data from the instrument separated by a space If the Time or Frequency channel is saved then it will be the first column in the data file Whether or not the Time Channel is included in the data file is specified by the Save Time Channel checkbox in the Disk Out dialog box For frequency domain data each data point is a set of two floating point numbers separated by a space the magnitude part and the phase part If the Time channel is saved then the frequencies in Hertz are written to the file TIME Sec CHO CH1 CH2 CH3 0000 5 0000 0 0000 0 0000 0 0000 0200 4 9900 0 0197 0 0000 0 0000 0400 4 9610 0 0785 0 0000 0 0000 0600 4 9120 0 1754 0 0000 0 0000 0800 4 8430 0 3089 0 0000 0 0000 1000 4 7560 0 4770 0 0000 0 0000 1200 4 6490 0 6769 0 0000 0 0000 1400 4 5250 0 9056 0 0000 0 0000 etc 0 00 0 Oy 100 5 c2 ASCII Plotter files are similar to CSV files except that the data is separated by spaces In addition the number of spaces usually tries to make the data look columnar when printed out Also if the Plotter file contains a header line to provide names for the channels the na
380. ns may contain only contain floating point numbers Each token type along with the syntax used to specify the token type is described in detail Page 10 6 Snap Master User s Manual Literal Match ABCDEFG A Literal Match character or character sequence is enclosed in double quotes If the characters in the incoming string do not match the Literal Match characters an error is logged in the Status Log and the RS 232 element is stopped This can be used for error condition checking for some instruments Place Holder 123ABC A Place Holder character or character sequence is enclosed in single quotes Any information in the incoming string interpreted as a Place Holder is ignored by Snap Master The length of the text in the Place Holder is ignored Channel Data A Channel Data token is indicated using a CH where the is replaced by the channel number to be used by Snap Master Valid channel numbers range from 0 to 31 The incoming string is interpreted as a floating point number Table 10 2 RS 232 Tokens Format Describes the tokens in each ASCII string Multiple Query When selected the Query string is sent out by Snap Master multiple times at every pacing interval When turned off the Query string is sent only once If the external equipment is being used as the pacer then the Multiple Query checkbox should be turned off This means that the Query string is sent only at the beginning of each frame If you want to use Sna
381. ns of hours of use there are times when you may encounter a repeatable problem with the software When you call technical support with a description of the problem please have a complete description of the problem and related circumstances which means that more information than Snap Master crashes when I run it is required You may be asked for copies of the instrument data or configuration files for Snap Master and for the sequence of events leading up to the problem including anything that has changed since the instrument last ran successfully Whenever practical HEM Data will assist in the timely resolution of such problems However the only way we can fix such a problem is if we can duplicate it Your assistance in this area is greatly appreciated e Application and Instrument Design Is NOT Included HEM Data s technical support service does not include the detailed applying of Snap Master to the design of a customer s specific application support customer written code in any language to access the features or files created by Snap Master or provide support for hardware not sold directly by HEM Data For assistance in these areas contact HEM Data for information on our consulting engineering services Getting Started Extended Support Programs Page 1 5 Because your contact point for technical support is the company you purchased the software from these technical support services may differ from HEM Data s Please contact your
382. nsor IDs exist on both computers One way to do this is to copy these four files from SYSDATA and transfer them along with the instrument files Input Y Output X Engineering Units Volts Amps PSI GPM C etc Figure 7 2 Applying Input and Output Ranges to a Sensor The Sensor element performs linear scaling to incoming channels assigned to a sensor from the database Expressed mathematically linear scaling is Y mX b where Y is the result of applying the Factor m to the value X and adding the Offset b Given two of the three sets of numbers m and b count as one set you can calculate the unknown values using simple algebra In linear scaling there are three sets of numbers to keep track of the Factor m and Offset b the Input Range Ymax and Y min and the Output Range Xmax and Xmin These values are all listed in the Sensor Assignments and Sensor Specifications tables But how do these apply to the physical sensor The key is to look at the values from the perspective of the sensor The purpose of the sensor or transducer is to convert some physical event measured in terms of engineering units to an electrical value to be read by an A D converter usually a voltage So the input corresponds to the physical events and engineering units and the output corresponds to the value coming out of the sensor Applying this further to the Sensor Database the Input Minimum is the value going in to the sensor in enginee
383. nt Line Function instrument Line Op1 instrument Line Op2 instrument Line WindowType instrument Line Width instrument Line StartingPt instrument Line DC instrument Lines Avg instrument Line Overlap instrument Line FramesToAvg string valid channel number None string string Numerator string Denominator string integer long int string Yes No string Yes No long int long int RRR RK RR KAA RARR RA RR D 16 Relay 2 gt e Format Comments string On Off string channel number single number of seconds per frame long number of points per frame string Yes No single Yes No integer comma separated list of channel numbers instrument ToggleNow activates Relay element instrument Triggered string Yes if Relay element is activated No if it is not instrument TriggerPoint long Point number where Relay element was last activated instrument TriggerType string TriggerOnChannel Value DDECommand instrument TriggerChannel string channel number instrument PreTriggering string Yes No instrument SpecifyAs string Points Seconds PercentageFrameLength Topic Item Exec R instrument InitialState instrument DrivingChannel instrument Duration instrument Points instrument UseDefault instrument StatusMessages instrument ChannelList e EP NES ASA KAR X instrument PreTriggerValue sing
384. ntheses and quotation marks You must stop the current instrument using the Stop command before you start another instrument Error message text Example If A0 40 Then Error Machine 1 Too Hot End If The Error command allows you to alert the user of a certain condition or keep track of a test s status The Error command writes the message text to the Status Log which adds a time and date stamp to the message In addition an Error causes the Status Log to open automatically to alert the user If the Display element is included in the instrument turn on the Status Bar to displays all Status Log messages Message message text Example If A0 lt 40 Then Message Machine 1 OK End If The Message command is similar to the Error command except that it is not interpreted as an error so the Status Log does not automatically open Messages are still displayed in the Display element s Status Bar DDEPoke DDECommandString Example If A0240 Then DDEPoke Snap Masterltest ins C Page 3 End If The DDE Poke command allows you to send a static DDE string from the Command element to other Snap Master elements or other programs Most values sent to a Snap Master element such as SampleRate do not take effect until the instrument is restarted You can only use a static value for the Value parameter you may not send out the value of a state variable or Command result channel When sending a DDE command string the
385. nts Main DisplayConfirmDelete string Yes No note Topic is Main instrument DefaultAutoLayoutMode integer 0 Off 1 One Channel Per Plot 2 Overplot Same Element Letter 3 Overplot Same Channel Number 4 Overplot With Same Units AutoLayoutOverplotMultipleY Axes Y Y string Yes No AutoLayoutOverplotWarnUnits Y Y string Yes No AutoLayoutOverplotNumChs Y Y integer AutoLayoutOverplotWarnDelete Y Y string Yes No DefaultCursorsSelectAllChs Y Y string Yes No DefaultCommandBar Y di string Yes No DefaultScrollBar Y Y string Yes No DefaultStatusBar Y Y string Yes No DefaultAutoRetrace Y Y string Yes No DefaultRetraceMode Y Y string Buffer Full DefaultPlotTechnique Y Y string AlN Automatic Printing Topic Item Exec Req Poke Format Comments instrument PrintMethod integer 1 ScreenCopy Display Page 2 ScreenCopy Desktop 3 High Res Black amp White 4 High Res Color string Yes No string Yes No string Yes No instrument PrintHiResSepLines instrument PrintHiRes WindowTitle instrument PrintHiResDateTime instrument PrintLeftMargin instrument PrintRightMargin instrument PrintTopMargin instrument PrintBottomMargin single single single NOS ON OK RRR SONUS UE NU single Default Print Settings Topic Item Exec Req Poke Format Comments instrument DefaultPrintMethod inte
386. o some results may vary from the theoretical responses The results were obtained by generating the data with the Analysis element performing a Forward FFT with the FFT element and measuring the response using the Display element with a dB 20x scale on a Mag vs F plot Page 14 14 Window Effects Illustrated Snap Master User s Manual Window Type Main Lobe Width Side Lobe Height dB Amplitude Spectral Lines Correction Factor Cosine 4th Power 29 100 267 NEN RUNE skirted skirted Bet Cosine BA 1 3 tt Parzen Joo 8 36 26 Riemann ue 8 ro Sine Sed Fower 340 Triangular 124 Figure 14 4 FFT Window Types To illustrate the effects of selecting a window type three examples are presented with the Forward FFT calculated using three different windows Rectangular Triangular and Blackman Harris The spectral lines are set to be at every 1 Hz the sample rate is 1000 and the window width is 1000 Rectangular o Blackman Harris TS ee FO dB 100 Frequency Hz Figure 14 5 Response of FFT Windows on a Single Frequency Figure 14 5 shows the effects of the different window types on an input signal with a single 100 Hz sine wave Each window type shows a strong frequency component at 100 Hz but on either side of the main frequency the windows differ Remember that the idea
387. o Toggle button Auto Toggle Settings Toggle When r Trigger Condition Type Channel Value zl Channel A0 Voltage zi Eondon Above x Pre Triggering Level One 3 Volts Triggering 0 T Pre Triggering uL C Level tun 0 Volts Specify As Points C Seconds C zz Frame Length Cancel Help Figure 15 6 Auto Toggle Settings 2 Select Channel Value from the Type combo box This means that the value of the Channel and the Trigger Condition determines when the Relay element is activated Page 15 6 Running the Instrument Snap Master User s Manual 3 For the Trigger Condition select Above 4 Set the Level One value to 3 volts 5 Press the OK button to close the Auto Toggle Settings dialog box 6 Press the OK button to close the Relay Settings dialog box IE Display Page 1 Eile Edit View Settings Start Layout Cursor Help E E Time Sec Figure 15 7 Results of Relay Tutorial When you run the instrument the original ramp wave channel AO is displayed in the left Y T plot and the Relay output channel BO in the right Y T plot If no plots appear then you have Auto Layout turned off Either change the Auto Layout method with the Options menu Default Settings command or add plots in the Display Layout table Utility Elements
388. o element we will configure the plots currently in the Display window along with creating new ones The majority of activity in this section will take place in the Display Layout dialog which is opened with the Display window s Layout menu command Ej fw Insert Delete Plot Settings Channel Settings Page Settings 0 Page Linked Tite On Plot Type Ch 1 Ch 2 Ch 3 Ch 4 Ch 5 Ch 6 o YST U iyvst JAD H H hi Ga VRRENI Baga ERE i gt j Figure 3 25 Display Layout Dialog Box The first thing you may want to change is the color of the waveforms in the Display window This will help differentiate the channels from each other as well as contrast both the color of the grid and the background The default colors for the Display window are configured by the Control Panel Color settings but we can alter the color of different portions of the plot from the Plot Settings dialog box To change the colors of the channels we use the Channel Settings dialog box shown in Figure 3 26 Display Page 3 29 Channel Settings Options Line Color BEEN Line Style Thickness g Show As C Label Number CEN Help Figure 3 26 Channel Settings Dialog Box Channels Y Axis tt There are a number of different ways to open the Channel Settings dialog box This tutorial shows you the quickest way there For k
389. o left The Y X Plotter uses the same configuration as the Oscilloscope but the X axis is now referenced against one of the input channels not as a function of time To emulate a portable volt meter the Display element plots the numeric data values using the Digital Meter display type A D D R DIG OUT A Sensor B Analog In C Analysis D Analog Out E Digital Qut The important feature about this instrument is its ability to output both analog and digital signals according to the system s input signal The input data is analyzed and monitored resulting in automatic decision making that will initialize subsequent actions for the test system Sensor B Analog In C Analysis D FFT E Display This Instrument configuration allows for analysis and manipulation of data in the digital domain The Analysis element uses digital filtering to remove unwanted noise from the signal and the FFT element performs a Fourier analysis on both the original and the filtered signals A D D R A Analog In B Analysis C Analog Out This instrument configuration allows for PID proportional integral differential Control The A D is used to acquire the incoming data the Analysis element calculates the Error and the PID output equations then outputs a value using the D A element Getting Started Page 1 3 1 2 Technical Support Registration Customer Support Where To Go For Help Please take the time to fill out and retur
390. oduces an inaccurate representation of the data This can occur in many different processes including converting analog continuous data to digital discrete data using Plot Techniques in to subsample the Display etc However there are two techniques used to controlling the effects of aliasing Nyquist s Sampling Theorem and anti aliasing filters The phenomenon of aliasing can be seen in Western movies as described by Enochson Sound amp Vibration March 1987 A slowing stagecoach wheel will appear to rotate backward stop and then rotate forward at a decreasing speed as the stagecoach comes to a stop According to Nyquist s Theorem the maximum rotational rate we can observe is one half of the 30 frames or samples per second frame rate or 15 spokes per second If the rate of the spokes exceeds this then the film cannot properly reproduce the continuous image of the rotating spokes The result of this aliasing is the apparent backward rotation of the image This occurs because the frame speed of the film is slower than the time taken for a spoke to rotate into the position occupied by the adjacent spoke when the previous frame was exposed When the speed of the spoke s rotation matches the frame speed the wheel appears to stand still Then as the wheel continues to slow the frame speed becomes high enough to picture the spokes accurately and the wheel appears to turn in the right direction at the right speed For example when the
391. oeeo eean e epearen etse ete ee teneret tenente Terate apaau eeh nnb ee a dnte nnt Saving Data From Only One Channel eese eere nennen enne nne enne eter enne Running The Instt tnent eec ee eret ede te ee eee en ES pe eere ene c ead 8 7 Tutorial Acquiring Digital Data eeeee esee cete eee e eene e eee eene eene ese eons esee ense sesso ssssesssseseesesse S 21 Buildime the Instr ment 5 nee pete ee rte e p eti e ep ect pente et Dr euet es 8 21 Configuring the Digital In Elem nht 2 nite id dinate 8 21 R n ning the Instr merit co etre ee FO te Ante RR Leno Ce bust aee Aa etes ostenta ts 8 22 Chapter 9 Counter Timer Special Wiring IDStructiols 3 4 epe RR RO RH REPRE PERDRE IEEE e rend 9 1 Counter Timer Input PANNI EET 9 2 Tutorial Measuring Pulse Counts eere esee etes ee eee eese eee eene sees esee sns sso eeoss see ssssesessssseeessssee AO Building the Instr trent i 5 ene ere ome ee e ees 9 6 Configuring A Counter For Pulse Counting eese nennen nennen ennne enne en eren 9 7 Configuring A Counter As An Internal Pacer eeseeeseeseeeeeeeeeeneen eene nenene nennen nnne 9 9 Signal Connections iei e t Re EE os OP e PEE EREMO RET e RIS peda S N e PO LEER OO ETT eir os 9 9 Running The Instrument 5 nero ent eee petu de fpatio etu eet ete te 9 10 9 3 Tutorial Frequency Measur
392. of Frames to Stop After 1 frame 4 Press the OK button to close the A D Demo Settings 5 Save the instrument with the button or with the File menu Save command Calculating The IST File Edit View Settings Builder Help eens F0 Result Ch Figure 14 11 FFT Settings for Forward FFT Tutorial 1 Open the FFT element by double clicking on the icon in the instrument window 2 Open the Equation Builder by pressing the button or select the Builder menu command Page 14 28 Snap Master User s Manual FFT Equation Builder Line 1 r Frequency Domain Calculation Besult Channel Category Function General Inverse FFT Hydraulic Auto Power Spectrum Electrical Auto Power Spectral Density Mechanical Cross Power Spectrum Ch 1 Channel AU Volts Ch 2 not used E r Scaling Window Result Frame Settings Window Width 200 E points Start At Point Overlap points Spectral Resolution 0 2500 Hz T Include DC Component Type Parabolic Farzon I Average Spectra Across 0 frames Rectangular Riemann X Partial Frame C Zero Extend Ignore Description Specifies the number of points analyzed by the function and the result is output after each width The Spectral Resolution is equal to the sample rate divided by the width lt lt Previous Line Cancel Help Next Line Figure 14 12 FFT Equatio
393. of data included in the data frame that occurred immediately before the trigger condition was satisfied Selects if the Pre Triggering amount is specified as Points Seconds or X axis units or Frame Length The remaining points in the frame that appear after the trigger event is called Post Trigger Data By specifying a Pre Trigger length of the entire frame or 100 it is possible to set up a Trigger To Stop condition With this setting the data will not be available until after the frame is acquired and the trigger condition is satisfied The amount of memory specified in the Memory dialog may affect how much Pre Trigger data is available If you ask for more pre trigger data than is available in memory Snap Master will use the maximum amount of data available The Complex Triggers group configures more detailed trigger conditions by cascading multiple stages using the standard types When the Multiple Stage Triggers check box is turned on each stage trigger must be satisfied before the acquisition frame begins Pressing the Insert button adds a new stage to the list with the current settings The Up and Down buttons rearranges the selected stage in the list and the Delete button removes the selected stage Data Acquisition Ranges Memory Page 8 9 Programmable input ranges Input range STOPES CATES M Sensor Range for All Channels 10 to 10 Volts M Cancel Help Figure 8 6 A D Input Rang
394. of the Load Register is calculated automatically from the Sample Rate defined in the Counter Timer Settings dialog 3 Close the 9513 Settings dialog by pressing the OK button 4 Press the OK button to close the Configuration dialog 5 Close the Counter Timer Settings window with the File menu Close command 6 Save the instrument with the button or select the File menu Save Instrument command Counter 1 Input Counter 5 Output Digital Common Interrupt Enable For our connections the Output pin of Counter 5 must be connected to the Interrupt Input pin and the Interrupt Enable signal must be tied to ground so the pacer pulses generate a hardware interrupt and cause Snap Master to sample the data Our input signal for Counter 1 is connected to the Source 1 pin Pin numbers shown for CTM 05 compatible hardware Page 9 10 Running The Instrument Snap Master User s Manual Al vs Time Frame 0 Time Sec 20 Figure 9 8 Results of the Pulse Count Tutorial When you run the instrument a waveform of Ticks vs Time appears in the display this input signal is a TTL square wave which was varied from 900 to 4500 Hz Note that the count wraps around from 65535 to 0 because the count range is 65536 and the Cycle is set to Repeat If you do not see any data make sure you have an Internal Pacer defined and the correct physical connections are made to generate a hardware interrupt 9 3 Tutorial F
395. ogs for each item appear on screen X Axis Settings Labet 1 I Show Label V Use Default Axis Major Divisions Types Liner Major Divisions 5 amp Logarithmic Show As Vertical Grid Action Moving gt Auto Clear C Tick Mark cC Location Y 0 x Hone v Show Axis Values Minimum and Maximum Iv Default Scale C All Major Divisions Minimum 0 Sec Mca Po o See Minor Divisions Minor Divisions 2 Format Default M ASE S z Show As C Tick Mark Significant Digits 1 E EN None comet _ uev Figure 3 3 X Axis Settings Y vs T Label You can define the label shown along the X axis using either the default or by turning off the Use Default check box and entering a custom label in the field If you do not want to show a label at all turn off the Show Label check box Page 3 6 Auto Clear Location Range Snap Master User s Manual Determines if the axis scale is either Linear or a Logarithmic base 10 Determines how the axis behaves when using the Linear axis and the Default Scale check box is turned off Moving mode waits until the Minimum value is reached plots the time between the Minimum and Maximum then clears the graph and displays each increment thereafter Stationary mode displays only the time between the Minimum and Maximum values Sweep mode uses the same time increment except that it does not clear the graph before plotting the new data Whe
396. olors When selected the cutoff values for the visual alarm are entered at the end of the One Color and Two Color lines These Three Color settings determine the colors used for the specified range of values Page 3 12 Indicators Indicator Settings Channel Settings Bar Meters Bar Meter Settings Axis Settings Snap Master User s Manual The Indicator plot type simulates a status lamp or an LED to represent relative values This plot type is well suited for visual alarms because you can set up each indicator to have multiple colors for the indicator and the background based on the current value The majority of the Indicator Settings operate the same as a Digital Meter Each indicator can be moved and sized within its own region when the Default Location is turned off A new Shape control lets you select the shape of the Indicator as either an Ellipse or a Rectangle The Channel Settings uses the same visual alarm color settings used by the Digital Meter plot type Bar Meter plots display single values using a vertical or horizontal colored bar This plot type is useful for data where the value is best displayed in relation to its overall value The bar meter can be customized by including user defined pictures directly in the display The majority of the Bar Meter Settings operate the same as the equivalent settings for a Digital Meter Fonts and Colors operate the same for Bar Meters with one exception the Background color set
397. olumn is a place where you can assign enter information about the equation line These comments are included for your convenience If this column is not visible you can turn it on in the Analysis Settings dialog 15 Position the selection box in the first row Label column Using the keyboard type Added Result then press ENTER The Label column assigns a channel label to each result channel defined in the equation line When this channel is referenced in this and other elements the channel label will appear along with the element letter and channel You can only label result channels with this column 16 Position the selection box in the first row Units column Using the keyboard type Volts then press ENTER The Units column assigns the units for each result channel defined in the equation line These units are used by the Display element to define the y axis units and are also stored by the Disk Out element when saving the result channel You can only assign units to result channels with this column 17 Switch to the main Snap Master window and save the instrument using the button or the File menu Save Instrument command Display Page 1 of x Eile Edit View Settings Start Layout Cursor Help LIZA SEIZE e Al ee ley amp 10 AO vs Time Frame 1 10 Al vs Time Frame i Added Result vs Time Frame 1 y Ss A0 Volts AY Nolts Added Result olts
398. olumns are in the table Result Channel Specifies the result channel for the smoothing Active Specifies if smoothing is performed on the channel Input Channel Specifies the channel being smoothed Process Specifies the process used by the element Label Specifies a unique channel name for the result channel Units Specifies the units for the result channel Utility Elements Page 15 13 Smooth i ng Smoothing Options i Result Channel B0 z Options Bise Time oz Specify As Seconds C Points C Frame Length Cancel Help Figure 15 18 Smoothing Options The Smoothing Options dialog defines the filter rise time for each channel This setting also affects the fall time for the filter Because the filter uses the equivalent of a block averaging filter the Rise Time setting actually controls the amount of data used for the block a larger rise time uses more data points for the block size Each channel can be configured with a different rise time by selecting each channel in the Result Channel list 15 6 Tutorial Smoothing This tutorial shows how to smooth two channels using the Smoothing element Instead of the A D Demo we use for most tutorials we will use the Wave Generator element to generate a square wave Building the Instrument Wave Generator B Smoothing Filter C Display Figure 15 19 Instrument for Smoothing Tutorial 1 Create a new instrument with the command in th
399. om Input and Analysis elements to another medium such as a plot data file or external signal 2 J ZA ge 5 lt Digital to Analog Output i Digital Output T Disk Output 1 S DDE Out Displays data on the computer monitor in a variety of formats Outputs analog data using D A hardware When placed in an instrument the element name changes to the model of the hardware Some hardware may use another icon Outputs digital data using Digital Output hardware When placed in an instrument the element name changes to the model of the hardware Some hardware may use another icon Writes data files to a floppy hard or RAM disk in binary and ASCII formats Outputs data from the Snap Master instrument to another DDE aware application Each of the window and table based elements share a common set of menu commands and associated Command Bar buttons The common Command Bar buttons their function and the equivalent menu commands are as follows 5 z e 5 E ae a a 5 w EB Description Clears all element settings Opens an existing element settings file Saves the current element settings to a file Undo the last command Cut the selected cells and send to the Clipboard Copy the selected cells and send to the Clipboard Pastes the Clipboard contents to the selected cell in the table Snap Master Basics File Menu New Seitings Open Settings Save Settings Save Settings As Print Table
400. om the list box The Integration function returns an array that has the same frame characteristics of the input function Because we already have a result channel RO with these frame characteristics let s assign a new channel to this element letter 6 Press the number 1 on the On Screen Keypad 7 Press the OK button to close the On Screen Keypad 8 Click on the i button Page 12 38 Snap Master User s Manual 9 Select the Calculus item in the Category list then double click on the Integration item in the Function list to open the Function Builder Integration Calculation intg range S0 S0 100 A0 Quick Functions m Options lt Default Rectangular gt p Rectangular Simpson s Rule be Syntax inta argument Description Calculates the area under the curve of argument with respect to time om em onm Figure 12 27 Function Builder for Integration In the Block Average example we first opened the Block function then the Average But for this example we are using the Integration function first and then the Range function Remember that the syntax follows how you would speak the function block average integrate over a range etc 10 Press the button to open the Range Function Builder Range Calculation range AB eje r Calculation Range Format lt Default Rectangular gt E Points Time Start Point s0 ch Ta mna End Point S0 100 enfo ina Syntax
401. omes into the instrument When the Histogram element is included in the instrument the Plot Type is automatically configured as a Histogram plot Plot Settings Plot Settings Histogram Title Histogram Iv Show Title Use Default Sub Title T Show Sub Title X xis Settings r Fonts ee 8 Z _Shannet Settings Labet Sub Title I Show X Axis Label X Label z r Y xis Settings Select Font Label SSS r Colors I Show Y Axis Label PHI ma Item Texi T Default Scale X Values ee po Y Values i Maximum 200 Select Color OK Cancel Help Figure 3 14 Histogram Plot Settings The Plot Settings for the Histogram plot are similar to a Y T plot with the addition of the X Axis Settings and Y Axis Settings to set the labels and ranges of data displayed Page 3 16 Channel Settings Main Color Appearance Filled 3 3 Menu Commands File Menu Print Display Snap Master User s Manual Histogram Channel Settings Channel Assignment Options Main D0 Color Appearance C Lines Bars Cancel Help Figure 3 15 Histogram Channel Settings Relative Bar Width 60 x Iv Filled Specifies the Histogram channel being plotted Specifies the color used for the data The Lines option plots thin vertical lines for each bin The Bars option uses the Relative Bar Width value to determine the width of the bars 100 fills the entire b
402. on history of each sensor in your sensor database If you run an instrument with an assigned sensor that is past its next calibration date an error message appears in the Status Log to inform you that Sensor is out of calibration 1 Open the Sensor Specifications table using the Specs menu command 2 Select the appropriate Automatic Calculation variable When you recalibrate a sensor you usually know the new Input and Output ranges from which the Factor and Offset are calculated In this case select the Factor and Offset as the dependent variables 3 Update the independent variables in their respective columns 4 Enter the new calibration date in the Last Cal Date column The calibration history for the sensor is updated when you move the selection box out of the row you are working on or when you press the OK button To view the updated calibration history for a sensor position the selection box in the row of the sensor then press the Calibration History button Signal Conditioning Page 7 13 7 7 Tutorial Additional Sensor Database Hints Copying An Existing Sensor Using The Sensor To Assign Channel Labels If you already have a prototype sensor in the database and you want to copy its settings simply enter a new ID for the sensor Instead of changing the ID a new entry is created in the database To make sure any new settings you have made are written to the database move the selection box off o
403. onds depending on the parameters during which time your hard disk light will turn on The values given by the test should not be viewed as absolute performance characteristics Rather they should be used to gauge performance of your hard disk with Snap Master NOTE Disk caching software such as SMARTDRV which comes with Windows will affect the actual performance of the hard disk Be sure to disable any cache software before using the Fast Binary data format File Exists C Overwrite Current File C Continue Without Saving Data OK Cancel Help Figure 4 12 File Exists Dialog Box If you start an instrument containing the Disk Out element and the file name already exists Snap Master will alert you with a dialog box before starting the instrument To inhibit this dialog and always overwrite the existing file select the Auto Overwrite check box in the Disk Out Settings dialog box Use Date Time File Name Saves the current data to a file using the current date and time as the file name Opens the Disk Out Settings dialog to change the file name When you press the OK button to close the Disk Out Settings the instrument will start Rename File Overwrite Deletes the existing file and writes the new data to that file name Current File Disables the Disk Out element for this run of the instrument so no data is written Continue Without Saving Page 4 12 4 4 Tutorial Saving Data To Disk Building th
404. onfiguration Connections 9513 Chip 1 Source Source 1 zl Prescaler Binary C BCD Count On Rising Edge C Falling Edge T FOUT Enabled Gate SETS j output Aways Lo a Source Divider A Registers Counter Settings Load Register 0 Hold Register mm Counter Count C Down Cp Function Internal Pacer T C Reload Load Only Load Hold Usage Pulse Count Cycle C Gnce Repeat CMode D F Format Binary C BED Custom Special Gate Disabled C Enabled Cancel Help Figure 9 6 9513 Settings for Pulse Count 10 Select Counter 1 from the Counter list 11 Select the Usage radio button then select Pulse Count from the Usage list For Pulse Counting the counter measures the rising edge of TTL pulses on the Source 1 input which is the input pin to counter 1 on the termination panel each time the INT IN pin receives a rising TTL edge The counter counts up from 0 to 65535 then it Repeats the counting until the end of the frame 12 Set the Gate to None We do not need a Gate signal so set that to None The Mode changes from F to D because we are not using a Gate signal Notice that there are few settings we can change when the Usage is defined as Pulse Count This is to prevent you from drastically changing the functionality of the Usage Of course you can set the Usage to Custom if you want to control all of the settings For this example we are assuming that you do not need th
405. ons Frame Time Z Transform Time or Frequency Data Ranges Shift Range Snap Master User s Manual time time points duration time pacing_channel Delimiters points Points per frame duration Frame duration in seconds Examples RO time RO time 500 5 RO time A0 This function should only be used with the Analysis element The Time function produces an array of points which are the relative frame time of the result element letter The result channel must always have frame characteristics sample rate points per frame and duration already assigned to use the time function without any parameters To generate a new point in the result function based on another channel use the pacing_channel parameter This also assigns the frame characteristics of the pacing channel to the result channel For example to monitor the frame time of channel AO the function would be written as time A0 If the frame characteristics for the channel have not been set anywhere else you may use the points and duration to assign them Note that this does not produce a paced result where the data appears in real time but rather fills the result array as quickly as possible z points arg1 Delimiters points Number of points shifted within the frame positive or negative shift Example RO z 1 A0 The Z Transform or Shift function produces an array of points which is identical to the contents of argl with the data shifted in
406. or a new cursor appears the anchored cursor remains in place and a line is drawn connecting the two cursors to represent the slope between the points Notice that the values in the Cursor Data table are showing the difference between the points and the Slope column is calculated automatically You can also click on the anchored cursor and move it independently of the relative cursor Page 3 40 Using Linked Cursors Snap Master User s Manual Display Page 1 Bee File Edit View Settings Start Layout Cursor Help pae D E US telele v 8 Marker Label Ch Linked Pt X Yalue Units Y Yalue Units Channel Label Type Slope Pg Plot ni NENNEN SO No 1168 106 Sec 4222063 Volts Voltage Pel 3999839 1 Channel Al Channel AO from A D Demo Time Sec Al vs Time Frame 1 Stopped instrument C SM DEFUSER EXAMPLE1 INS 11 10 97 11 48 37 AM Figure 3 42 Display With Relative Cursor Now that we have a cursor on the upper plot let s add a cursor to the lower plot and link them together so they move in tandem 1 Press the button or select the Cursor menu New Cursor command 2 Move the mouse pointer over the lower plot and press the right mouse button A cursor now appears on the strip chart of channel A1 You should see two entries in the C
407. or information on how your hardware uses External Pacing refer to the documentation accompanying your hardware Data Acquisition Page 8 5 Sample Rate Specifies how often the A D hardware reads data With an Internal pacing clock Snap Master selects the closest sampling rate supported by the hardware One of the most perplexing issues for newcomers to analog to digital conversion is the selection of a sampling rate Nyquist s Sampling Theorem see Appendix C states that for an accurate representation of the original signal the sampling rate must be at least twice that of the highest frequency being sampled For example if you were trying to sample signals in the range of human hearing 20 20 000 Hertz you would have to specify a sampling rate of at least 40 000 Hertz in order to accurately represent the entire range In practice sampling rates up to 10 times the desired frequency range are used to acquire data with good resolution In the real world there is a limitation to how fast each channel of data can be sampled This is related to the maximum sampling rate of the A D board and the number of channels being scanned referred to as the aggregate sampling rate Max Hardware Sample Rate Max Sample Rate per Ch 2 Y_ Number Chs Sampled Pacing Units Specifies the X axis units for the element When the Pacing Units are seconds the Sample Rate is measured in Hertz When an External pacing clock is used the pacer
408. or noise to infinite frequency but in some cases you may know the upper limit When the sampling rate exceeds the minimum defined by Nyquist s Theorem the data is said to be oversampled Conversely if the sampling rate is less than two times the frequency of interest the data is undersampled Aliasing is most noticeable when undersampling occurs In an ideal world you would conservatively assume that a certain amount of high frequency noise is present so you would use an infinite sampling rate In the real world an infinite sampling rate is not possible so you must always undersample and risk a controlled amount of aliasing When you are acquiring data with the Data Acquisition Module then the sampling rate of your input device defines the maximum frequency you can measure Adjust the sampling rate to either maximize the frequency response of your data higher sampling rate or to minimize the number of data points read and possibly stored to disk lower sampling rate When generating signals with the Wave Generator element make sure that the frame characteristics of the result element have a sufficient resultant sampling rate for the frequency of the signals you are generating Page C 2 Anti Aliasing Filters Snap Master User s Manual One way of minimizing aliasing with practical sampling rates is to use an anti aliasing filter Anti aliasing filters are low pass analog filters whose cutoff frequencies are set at or below one half
409. orkspace while another instrument is running but you cannot start another instrument until the first instrument is stopped The Comment Field in the instrument window is a text box where you can enter any additional information about your instrument Helpful text might include a title for the instrument or a specific use of that particular configuration Page 2 4 Snap Master User s Manual File Menu New Instrument Create a new instrument window Open Instrument Open a saved instrument Instrument Viewer Instrument Viewer File List Instrument Contents FFT of Sawtooth and Inverse FFT of result Double click On FFT icon for calculations A WaveGen B FFT C Display FILTERS INS GAEXAMPL INS HISTOGRM INS LONGTE 1 INS LONGTE 2 INS PILOT INS Figure 2 3 Instrument Viewer In the Open Instrument dialog there is a Viewer button which opens the Instrument Viewer The Instrument Viewer lists all of the instruments in the current directory set in the File Open dialog When you click on an instrument in the File List an overview appears in the Contents picture box including the icons and comments in the instrument Pressing the Close button automatically enters the name of the instrument in the File Open dialog Save Instrument Save the instrument Save Instrument As Save the instrument as a new file Close Instrument Closes the active instrument Exit Program Exits Snap Maste
410. ort None Vertical Grid Tick Mark None Minimum and Maximum All Major Divisions None Tick Mark Page D 8 Snap Master User s Manual Y Axis Settings Waveform Plots Topic Item Exec Req Poke Format Comments Plot Y AxisDefaultLabel Plot Y AxisType string Yes No string Y T Linear Logarithmic db 10x db 20x string Yes No string contents of Location combo string Yes No string contents of Format combo string None Vertical Grid Tick Mark string None Minimum and Maximum All Major Divisions string Yes No string None Tick Mark string replace Axis with the axis number being edited 1 10 string Yes No single single string fill out edit controls as passed integer string aK SS Plot Y AxisMultipleY Axes Plot Y AxisLocation Plot Y AxisDefaultScale Plot Y AxisFormat Plot Y AxisShowMajorDivisions ANCUS KASS X x Plot Y AxisAxis Show Axis Values Plot Y AxisAxis Rotate Values Plot Y AxisShowMinorDivisions Plot Y AxisAxis Label AK SESS Plot Y AxisAxis ShowLabel Plot Y AxisAxisZ Min Plot Y AxisAxis Max Plot Y AxisAxis SignificantDigits Plot Y AxisAxis MajorDivisions Plot Y AxisAxis MinorDivisions KASSAN KASSA Channel Settings Waveform Plots Topic Item Exec Req Poke For
411. ount proceeds until the second T C when the counter reloads the Load register value and waits for the next Gate condition before restarting This differs from Mode K where the Gate is used to affect the duration of the High and Low times Software Triggered Strobe with Level Gating and Hardware Retriggering At the beginning of each frame the Load register sets the initial value of the counter The count accumulates on a Source edge only when the Gate condition is satisfied Upon reaching T C the counter reloads the Load register value and disarms itself until the next frame begins If a Gate edge occurs so the condition is not satisfied before T C is reached the next Gate edge where the condition is satisfied causes the counter to be reloaded from the Load register on the next Source edge Counting resumes on the second Source edge while the Gate condition is still satisfied Each Gate edge causes the counter value to be transferred to the Hold register Counter Timer Mode O Mode Q Mode R Mode S Mode V Mode X Page 9 17 Software Triggered Strobe with Edge Gating and Hardware Retriggering This mode performs the same function as Mode N except that counting only occurs after the Gate condition is satisfied and the Gate level does not modulate the counting function All Source edges that occur after the Gate condition is satisfied are counted until the T C is reached After T C the counter reloads the Load value and waits fo
412. our spreadsheet document from the list If no items appear in the list make sure that Excel is running If you are using a different spreadsheet and the topic names do not appear in the list turn off the Use List To Specify Topics checkbox in the DDE Conversation dialog and enter the topic name manually 3 Position the selection box in the first row Link Item column and type R C or the cell where the data is located 4 Position the selection box in the first row Label column and type Excel Link 5 Close the DDE In Assignments using the File menu Close DDE In command 6 Save the instrument with the button or select the File menu Save Instrument command Page 6 14 Running the Instrument Snap Master User s Manual X Microsoft Excel Bookt oi 18 x bor File Edi View Inset Format Took Data Window He oela eps aspe ola zla esu us epo A One nal us EIE foo wl zl sisse ese sel 2 ti mid 2 1 2 3 4 5 6 7 8 3 14 4 gt N Sheett Sheet 7 Sheel3 Z Sheet Sheets Sheets Sheet f Sheet Sheel3 Z Sheerl 5 4 mie Ready m 2 NUM ay EO ES ET E iJ Jal nomm e i Excel Link vs Time Frame i Excel Link Volts a0 Time Sec Figure 6 9 DDE Data Transfer from Excel to Snap Master Try to size the
413. ow behaves better in the best case but not much In the best case the main lobe width is wide with most of the energy is below 60 dB In the worst case the main lobe width is very narrow but the side lobe is not attenuated very much and the result is virtually skirted Half Cycle Sine Best Case Worst Case Frequency Response s 60 dB Bandwidth 31 2 2 1 dB Spectral Lines Main Lobe Width 115 13 Spectral Lines Side Lobe Height 82 7 dB 111 3 dB The Half Cycle Sine window responds impressively in the worst case with a severe drop off in the main lobe below 60 dB The best case shows most of the main lobe energy below 60 dB with a virtually skirted response FFT Hamming Frequency Response 60 dB Bandwidth Spectral Lines Main Lobe Width Spectral Lines Side Lobe Height BSSR Bee SB Oo Best Case 3 7 4 dB 109 7 dB BBSR Bee SB 11 1 Page 14 21 Worst Case E A 95 42 7 dB The Hamming window is another case where there is a large difference in response depending on where the frequencies of interest lie The best case scenario has excellent response with a narrow main lobe and good attenuation below 60 dB In the worst case the response is almost skirted with a relatively high side lobe Note that the side lobe rises about 20 dB from the bottom of the main lobe before the skirting begins Hann Frequency Response 60 dB Bandwidth Spectral Lines Main Lobe Width Spectral
414. p Master as the pacer to request a new data point at the rate specified by the Sample Interval turn the Multiple Query check box on Delimiter Defines the character sequence separating each data token May include the Escape Sequences described above Only one Delimiter definition is allowed and cannot change between data packets In addition the Delimiter must be different than the Terminator and the Terminator cannot be a subset of the Delimiter For example if the Terminator is v vi then the Delimiter cannot contain this sequence Termination Defines the character sequence separating each data packet May include the Escape Sequences described above Only one Termination definition is allowed and cannot change between data packets In addition the Delimiter must be different than the Terminator and the Terminator cannot be a subset of the Delimiter RS 232 Configuration Page 10 7 RS 232 Configuration Name TempScan r Handshaking r COM Port Settings ed Xon Xoff RTS CTS DSR DIR Port COM1 Baud Rate 9600 pistes ai sat El b sj ue Data Bits 8 zi Phone Number DO O None rj i Parity NONE Modem Timeout po MT Tees D me me neve Cancel Help Figure 10 3 RS 232 Configuration The Configuration dialog defines the serial communication parameters for up to eight separate devices Each device can be assigned a unique name using the Name text box The
415. p occurs as a logarithmic function of time for the stage length Amplitude Specifies the peak to peak amplitude of the waveform Rectify Takes the absolute value of the waveform Any values below zero are negated so the result is positive Damping Varies the amplitude as a Linear amplitude increases or Exponential amplitude decreases function of time The damping Coefficient determines the relative damping speed for the stage length Wave Generator Frequency Modulation Ramp Page 5 5 DC Offset Specifies the offset from 0 volts for the resulting waveform Phase Specifies the phase shift of the resulting waveform A Phase change of 90 produces a cosine wave Frequency Modulation Settings r Frequency Modulation Parameters Carrier Modulator Frequency fo Hz b Hz Amplitude fio Volts P o Volts DC Offset j0 Volts Phase fe Degrees eel Eee prz Figure 5 6 Frequency Modulation Settings The Frequency Modulation function varies the frequency of a single frequency sinusoidal wave the Carrier as a function of the magnitude of another single frequency sinusoidal wave the Modulator To ensure that all of the information in the Modulator signal is retained in the modulated result the frequency of the Carrier signal should be much higher than the frequency of the Modulator signal Frequency Specifies the frequency of the Carrier sine wave and Modulator sine wave Amplitude Specifies the peak to peak amplitud
416. pe and the template settings from one plot type can not be applied to another plot type Displays the data from left to right with a stationary X axis based on time For time channels with more than one point per frame Y vs T is the default plot type for the Auto Layout function This is the best general purpose display type and is best suited for display during both data acquisition and replay Page 3 4 Plot Settings Snap Master User s Manual Plot Settings Y vs T Title Y vs T Iv Show Title Use Default Sub Title T Show Sub Title r Plotting Technique r Fonts X Axis Settings ide i Item Title n c Mode Automatic x Sub Title Diaw Lnes Ef Select Font Channel Settings r Show Colors Legend Item Text e X Values Inside Grid Y Values z C Right Margin moia Select Color OK Cancel Help Figure 3 2 Plot Settings Y T Title Each plot can have up to 2 rows of text for a Title The main title of the plot is located in the Title field and is the same as the title in the Display Layout table For time domain plots the Default title consists of the Channel Number or Label vs Time The Sub Title field lets you enter additional text that appears on a line between the title and the plot grid Plotting Techniques Snap Master includes several Plotting Techniques which can improve the performance of the Display window by changing the number of points a
417. pear and tell you that Sensor HEM 001 is out of calibration 8 Set the Input Minimum to 0 the Input Maximum to 50 and the Engineering Units to C With these settings sensor HEM 001 converts voltage to temperature measured in degrees C With the values we have entered the factor is 2 5 and the offset is 25 9 When you are done press the OK button When you return to the Sensor Specifications table the database is resorted with the new sensor and it appears in the table in its proper alphabetical order If you want to edit the sensor you can use the Edit Sensor button E which uses the same dialog as the Insert Sensor dialog Alternatively you can edit the settings directly in the table the F2 key lets you modify the value without retyping it entirely 10 Press the OK button to close the Sensor Specifications dialog Page 7 10 Snap Master User s Manual 11 Select the File menu Close Assignments command to close the Sensor Assignments table 12 Select the File menu Close Instrument command to close the instrument file You do not need to save your changes 7 5 Tutorial Using The Sensor Element Building The Instrument Now that we have included our new sensor in the database we can use the Sensor element to scale data from the A D Demo into engineering units as well as assign a label to the channel In an instrument the Sensor element is configured as an input to an acquisition element usually as an A D
418. peus mesa sine J Stop After fo hanar Configuration c Status Messages Cancel He Figure 11 4 A D Demo Settings 2 Change the Number of Frames to Stop After 1 frame 3 Press the OK button to close the A D Demo Settings Configuring the Make sure you have a physical connection on the hardware s termination panel for the output of A D Hardware D A channel 0 or channel 1 to A D channel 0 or channel 1 1 Open the A D Settings by double clicking on the B A D element B Device 1 A2D Settings Untitled of File Edit View Settings Device Help Figure 11 5 A D Hardware Settings 2 Press the button or select the Settings menu Frame Settings command Page 11 6 Configuring the D A Snap Master User s Manual Frame Settings Pacing _ Frame Length gt gt Type Hardware zl Duration g Sec Location Internal C External C t of Points 500 Sample Rate 100 4 Sec ES of Frames Pacing Units sec m C Continuous X Axis Label Time Stop After fi frames Cancel Help Figure 11 6 A D Frame Settings 3 Set the Type to Hardware 4 Change the Sample Rate to 100 5 Change the Frame Length to a Duration of 5 seconds 6 Change the Number of Frames to Stop After 1 frame 7 Press the Frame Settings 6 Save the instrument with the button or select the File menu Save Instrumen
419. pical Usage 1 Parity Error Detected 2 IRQO Interval Timer Output 0 3 IRQI Keyboard IRQ2 Interrupt for IRQ9 IRQ15 4 IRQ8 Real Time Clock 5 IRQ9 6 IRQIO 7 IRQ11 8 IRQ12 9 IRQ13 Math Coprocessor 10 IRQ14 Fixed Disk Drive Controller 11 IRQ15 12 IRQ3 Serial ports COM2 and COM4 13 IRQ4 Serial ports COM1 and COM3 14 IRQ5 Parallel port LPT2 15 IRQ6 Floppy Disk Drive Controller 16 IRQ7 Parallel port LPT1 DMA Channels The following table describes the standard usage for DMA channels in the PC Check the documentation for your computer system and all add in hardware to determine the available DMA channels for your computer Channel NAYAANBRWNK CO Typical Usage Unavailable on some PCs Floppy Disk Controller XT only Hard Disk Controller Cascade for DMA channels 5 to 7 PS 2 only Hard Disk Controller Page E 2 Snap Master User s Manual The following table describes the standard PC AT base address usage expressed as hexadecimal values Check the documentation for your computer system and all add in hardware to determine the available addresses for your computer Base Address Address Range Typical Usage 200 to 20F Game I O 208 to 20F not used 210 to 21F Expansion Unit 218 to 21F not used 220 to 22F Reserved 230 to 23F Reserved 240 to 24F Reserved 250 to 25F 260 to 26F 270 to 27F Parallel port LPT2 270 to 277 not used 280 to 28F 290 to 29F 2A0 to 2AF 2B0 to 2BF Alternate EGA VGA adapter 2C0 to 2CF Alter
420. plex conjugate of Gp Gaa is the Auto Power Spectral Density of a and G is the Auto Power Spectral Density of b The Coherent Output Power function produces a specialized power spectrum that reports how much of the power in the output signal listed in the Ch1 column is caused by the input signal listed in the Ch2 column The two channels being analyzed must have the same frame characteristics The result units are the output units squared over the input units such as volts2 volt or psi2 Ib By definition if the output and input both equal 0 then the result is also 0 If the input is 0 and the output is non zero then the result is infinite which is defined as 102 by Snap Master This Coherent Output Power is different from the Auto Power Spectrum which produces the power spectrum of the output without regard to the input source GG The mathematical description for the Coherent Output Power function is COP aa where b the output is the channel listed in the Ch1 column a the input is the channel listed in the Ch2 column G is the Cross Power Spectral Density of a and b G is the complex conjugate of G and G is the Auto Power Spectral Density of a The Transfer function represents the frequency response of a system with an output Ch1 and an input Ch2 The magnitude and phase response ratios comprise a complete frequency domain representation of the system In order to perform a Transfer Function the two ch
421. r Element Menu Pipe Mode When creating an instrument the flow of data between elements is defined by the connection of data pipes These pipes are directional and include an arrow indicating the direction of flow To activate or deactivate Pipe Mode select the Elements menu Pipe Mode command or press the button in the Command Bar Connecting Elements To connect two elements together use the following procedure e When the Pipe Mode cursor is UE the arrow points to the upper left click once on the source element or the element where the data is coming from e When the Pipe Mode cursor is ES the arrow points to the lower right click once on the destination element or the element where the data is going to The elements are now connected so that data flows between them in the direction shown e Repeat for as many connections as your instrument needs Snap Master Basics Re Letter Mode Page 2 5 Disconnecting Elements To disconnect the pipe between two elements use the same procedure used for connecting the elements e When the Pipe Mode cursor is UE the arrow points to the upper left click once on the source element e When the Pipe Mode cursor is ES the arrow points to the lower right click once on the destination element The pipe between the elements is cleared Each element in a Snap Master instrument has an associated element letter which is used to distinguish the different elements Using Re
422. r Custom Commands Device Menu 1 8 Device Overview Page 8 11 If you are running Windows in 386 Enhanced Mode try not to allocate so much memory that Virtual Memory is used This is because virtual memory uses the hard disk which has a slower access time than RAM which may cause A D Overrun problems at higher acquisition rates If an A D Overrun occurs try lowering the number of points stored in memory lowering the sample rate or optimizing even removing other elements in the instrument such as Display try using the Automatic Plot Technique or Disk Out try using a binary file format When the menu option is checked run time information about the element is sent to the Status Log Under normal operation this option should be turned off If an error is encountered during operation of the instrument the message will be sent to the Status Log regardless of the Status Messages setting When the menu option is checked any errors underruns or overruns encountered during operation of the instrument causes the instrument to stop immediately When the menu option is not checked the element continues operating in spite of the error Some drivers add special menu commands to configure a unique hardware feature Please refer to the documentation accompanying your hardware or any help files supplied by the hardware manufacturer Specifies the device used for this element All installed hardware is listed by device number in this menu
423. r 3 Close the DDE In Assignments using the File menu Close DDE In command When you start the data client instrument the one with the DDE In the client checks to see if the data server is running If the server is not running the client asks if you want to start the server When you answer Yes the server instrument is started and the data is sent to the Display on the client machine If you answer No then no data will be transferred If the server is already running the Display on the client begins plotting data from the actual frame position of the server For example if the server is 5 seconds in to a 20 second frame then the client begins plotting data at 5 seconds Sensor Database Page 7 1 Chapter 7 Sensors amp Signal Conditioning 7 1 Sensor BET UE A E E EER 771 7 2 Sensor Menu Commands 7 3 Signal Conditioning sccscccssscssssccsscssssecssssesssscssessssssssssssnsssssssscnssesssssssssscnsscsssscnssssscsssescssosssscscsscscssssssssesses J 7 4 Tutorial Adding A Sensor To The Sensor Database scssssssscsssecsssscssssscsssscsssscsssessssssssssosssscsssscssssssssssssees 7 8 7 5 Tutorial Using The Sensor Element eee eee eee eee eee ee neenon stones esos se sns sess sess see enssesnssesossesnsseesseessseeseee 7 10 7 6 Tutorial Updating a Sensor s Calibration History 7 12 7 7 Tutorial Additional Sensor Database Hints eee esee crees esee
424. r 2 2 13 8 Elements 2 14 Workspace 2 6 Status Log 1 7 2 2 2 6 2 8 2 9 2 21 7 3 8 11 8 15 8 20 8 22 10 6 11 2 11 7 11 8 13 11 Status Messages 2 8 2 21 8 11 11 2 Strip Charts 3 9 3 32 Subroutines 13 4 13 12 Subtraction 12 12 Support 1 3 Sweep Graphs 3 3 3 6 Sweep Time 2 21 8 5 System Requirements 1 5 T Table Columns 2 14 Printing 2 13 Tangent 12 14 Inverse 12 14 TCLinear 2 11 Temperature 15 7 Templates 3 3 Terminal Count 9 4 9 6 9 14 9 15 Text Annotations 3 2 3 27 Thermocouple 2 11 Thermocouples 15 7 Thickness 3 29 Throughput Tester 4 11 Tick Marks 3 7 Time Function 12 4 Time Of Day 3 6 Time Shift 12 22 Toolbox 2 3 2 6 Transfer Function 14 9 14 36 Transmissibility 14 11 Triangular Window 14 15 14 16 14 24 Trigger To Stop 8 8 15 2 Triggers 8 15 Bypass 8 8 Complex 8 8 Truncate 12 25 Index U Undersampling 12 10 V Variance 12 18 W Wall Clock Time 3 6 Wave Generator 2 11 When 12 20 Window Width 14 24 Windows FFT 14 11 14 24 14 29 Windows 95 1 8 Windows NT 1 8 Workspace 2 1 13 8 Write Data Files see Disk Out X X Axis Label 2 20 5 9 Y Y vs X Plots 3 9 3 32 Y Axis Settings 3 7 Z Z Transform 12 22 Zoom 3 2 Zoom Linked 3 18 3 23 Zoom Out 3 18 Page X 5
425. r User s Manual 4 3 Disk Out The Disk Out element writes data from the instrument to a disk file You can use any disk drive 1 supported by Windows to store your data including hard disks and RAM disks Disk Out writes files in Snap Master native formats as well as exports data to ASCII files Disk Out Settings C Date And Tine C ence File Seed c eum e B ixi Overwrite eme File Name Directories Help ftestdata dat exsmMdefuser 52110282 dat Save Options 62511152 dat amp sm batchODT dat i defuser File Comments batch002 dat capture dat Disk Out Defaults examb1 dat junk dat he Throughput Tester File Format Drives Standard Binary dat x c hardly E Network ASCII File Export Number Format Decimal 6 4 Volts f Save Time Freg Channel Scientific x 4 exXX Volts C Engineering 3oo 4 kVolts Figure 4 7 Disk Out Settings The Disk Out Settings dialog box specifies the name of the data file and the format it is written to A number of file naming methods are available as well as the native and generic Snap Master data file formats The middle of this dialog operates like the standard Windows File Open dialog boxes The File Name field specifies the data file to be replayed from the specified Directory the default directory is SM DEFUSER To specify the type of file select the appropriate choice from the File Formats list When you select a File Format the extensio
426. r example if a value of 100 is specified then the last 100 points used for the previous FFT result frame are used as the first 100 points of the current FFT result frame The default value for the Window Overlap is zero points Determines if the spectral line at 0 Hz is included in the result The DC Component is often removed when it is large in comparison to the remainder of the frequency spectrum Removing the Oth spectral line is equivalent to subtracting the average of all data in the window while in the time domain If you perform a Forward FFT and later plan to perform an Inverse FFT on the data removing the DC Component will cause the Inverse FFT to present the data centered around 0 The DC option is not available for the Inverse FFT function Determines if successive FFT result frames are averaged and the number of frames averaged Averaging is used to lower the noise margin by minimizing random noise between result frames If the number of frames averaged is larger than the number of FFT result frames produced by a time domain data frame the window averaging function averages frequency data across different time based data frames To average all frequency result frames within a time domain data frame enter 0 or A in the Frames Avg column so the entry is Auto For example assume you are performing a Forward FFT on one time frame with 1000 points using a window width of 250 points Window Averaging is turned on and Frames
427. r programs via Dynamic Data Exchange or DDE If you are on a Microsoft Network computer such as Windows for Workgroups you can also receive data from other computers running Snap Master Analysis elements process data from Input elements and output the results to other Analysis elements or Output elements a e al t as Relay Thermocouple Linearizer Smoothing Analysis MultiFrame Histogram Command Acts as a data controlled switch to turn data pipes on and off while the instrument is running Converts the voltage input from a thermocouple into temperature units Performs a low pass smoothing filter on the selected channels Performs time domain calculations and outputs the results as new data channels Performs summing or averaging in either the time or frequency domain over multiple frames of data Performs summation averaging or counting on data to produce data grouped into bins Performs commands based on logical decisions using IF THEN ELSE statements Page 2 12 Output Elements Menus And Command Bar ed RET sae Frequency Analysis Snap Master User s Manual Converts time domain data to the frequency domain using Fast Fourier Transform power spectra transfer and coherence functions and outputs the results as new data channels Performs calculations on the magnitude portion of frequency domain data using the same tools as the Analysis function Output elements send data fr
428. r sample rate of the element letter A would be A SampleRate For a complete list of DDE Items for all Snap Master elements please refer to Appendix D To illustrate the relationship of the components of a DDE conversation let s draw an analogy between DDE and a telephone number The Service Name is equivalent to the area code which determines the region of the country the Topic is the phone number which specifies the actual phone location and the Item is the information discussed with the person on the other end of the line Dynamic Data Exchange DDE Link Types DDE And Snap Master Page 6 3 As an example assume that you want to change the Sample Rate of element A to 100 Hz For the telephone equivalent say you are calling HEM Data with the instruction Change the Sample Rate of element A in the instrument TEST INS to 100 Hz The conversations would look like this Service DDE Snap Master Phone 810 Topic DDE TEST INS Phone 559 5607 Item DDE A SampleRate 100 Phone Change the Sample Rate Conversation DDE Snap Master TEST INS A SampleRate 100 Phone 810 559 5607 Change the Sample Rate DDE is similar to a phone system because there is a standard method to contact someone the area code and phone number but the actual information discussed depends on the parties involved The items discussed in the conversation can change but if you want to change the phone number you are talking to a n
429. r scaling equation mX b If you have a sensor assigned to this channel using the Sensor element this column is not editable Offset Specifies the adder for the channel to convert from volts to engineering units Also known as the b term for the linear scaling equation mX b If you have a sensor assigned to this channel using the Sensor element this column is not editable Min Shows the minimum value that can be acquired for this channel based on the input range setting and the Factor and Offset values This column is not editable Max Shows the maximum value that can be acquired for this channel based on the input range setting and the Factor and Offset values This column is not editable Data Acquisition Dialog Interface Page 8 3 Label Specifies a long name for the channel This label accompanies the channel number for use in the Display element and in data files If you have a sensor assigned to this channel using the Sensor element this column is not editable Units Specifies the units of the channel The default units are Volts If you have a sensor assigned to this channel using the Sensor element this column is not editable A Device 1 CIO DAS16 A D Settings r Pacing Type Hardware DMA Location Internal C External Sample Rate 1000 7Sec Pacing Units S ec z X Axis Label Time Triggers Free Running p Frame Length Input Ranges 0 to 10 Volts C Duration
430. r select the button in the Command Bar to open the Instrument Settings dialog Select the Two Line Option in the Title group then press the OK button 5 Save the instrument as EXAMPLE with the button or select the File menu Save Instrument As command File Save As x File Name Directories example ins c sm defuser 091 71p01 ins a aes Cancel analysis ins Cy sm block ins Gy defuser Network compare ins faexl ok ins fft ins filters ins File Type Drives Instrument hd c hardly m Because this is the first time the instrument is being saved the File Save As dialog box appears The File Name field is highlighted so all we have to do is type EXAMPLE Page 2 18 Placing and Connecting the Elements Snap Master User s Manual It is not necessary to type the INS extension in the file name because Snap Master will automatically add it for you It is not recommended that you specify an extension other than INS The default directory for your instruments is the DEFUSER subdirectory which is what we will use for this example NOTE It is important to save your files frequently so that no information is lost The tutorials are designed to remind you to save the data at the end of each section A D 1 Place the A D Demo element m in the instrument window Position the mouse pointer over the A D Board icon in the Toolbox Click on the left mouse button If you own the Data Acquisition
431. r some other function that produces a Boolean result filter arg1 Example RO filter AO The Smoothing Filter also called a Hanning filter function is a simple low pass or averaging 2nf 14 cos smoothing filter The frequency response of this filter at a frequency f equals ____ s _ where f is the sample rate of argl fir order type f1 f2 window argl Delimiters order Value between 1 and 400 type Frequency response shape f1 f2 Corner frequencies window Scaling Window Example RO fir 10 L 20 R AO The FIR Filter model is a purely digital filter so it has no analog filter counterpart FIR filters simulate the impulse response of the filter which is equal to the inverse Fourier Transform of the filter s frequency response An FIR filter produces a waveform with a linear phase response which means that overall shape of the waveform is preserved There are either four or five parameters depending on the type which must be specified for the FIR filter The order specifies defines the number of filter coefficients used which affects the slope in the filter s transition bands The higher the order the steeper the slope of the filter in the transition band the range of frequencies between the pass band and stop band frequencies However higher filter orders require longer processing time The type specifies the response type of the filter This setting also affects if the f2 parameter is used only Band
432. r the next Gate edge If a Gate edge occurs before T C is reached the next Source edge when the Gate condition is satisfied causes the counter to reload the Load register value and counting resumes on the second Source edge Unlike Modes C F I and L the Gate input causes the counter to restart the count Rate Generator with Synchronization Event Counter with Auto Read Reset At the beginning of each frame the Load register sets the initial value of the counter The count accumulates on a Source edge only when the Gate condition is satisfied Upon reaching T C the counter reloads the counter with the Load register value If a Gate edge that satisfies the Gate condition occurs before reaching T C the contents of the counter are transferred to the Hold register and the next Source edge while the Gate condition is still satisfied transfers the Load register value to the counter Counting resumes on the second Source edge after the retriggering Gate edge Retriggerable One Shot This mode performs the same function as Mode Q except that the Gate edge only determines when to start counting Upon reaching the T C the counter is reloaded with the Load register value All Gate edges retrigger the process by moving the counter value to the Hold register resetting the counter with the Load register value on the next Source edge and accumulating on the second Source edge after retriggering This differs from Mode Q which uses the level rather than t
433. range Start amp t EndAt argumenti Description Specifies the start of the range You can use the Find function to automatically locate the start of the ran d Cance Help Figure 12 28 Function Builder for Range 11 Press the button in the argument and click on channel AO The argument for the Range function is the channel we want to examine Remember that the Range function sets all data before the Start Point and all data after the End Point to zero For the Integration function in this example this means that the integration does not appear to begin until the start point the integration of zero is zero If the Range function were put before the Integration there would be an offset at the start point because the function is looking at a range of the integration 12 Press the button in the Start At point and click on channel SO In the previous example we defined channel SO as the data point where AO goes below 0 We can use this result for the Range function parameter as if it were a constant If you already know the point number where you want to begin the range you could enter that number directly Analysis and Frequency Analysis Page 12 39 Running The Instrument 13 Press the button in the Stop At point and double click on channel SO then add 700 after the channel This says that the Range function ends 100 points after AO is less than 0 the contents of channel SO It is possible to enter the Find fu
434. re not enough spectral lines between the frequencies for a sufficient drop The Triangular window suffers from its large side lobe height which interferes on either side of the main frequencies to produce inaccurate readings at the off frequencies There are other combinations of frequency cases but these three provide a good illustration of the interdependence between the window type the width of the main lobe and the number of spectral lines The following sections discuss each window type and its response in both the best where a single frequency falls on a spectral line and worst where a single frequency is between spectral lines cases Best Case Worst Case Frequency gt gt Response hs gt eM PR Pt ony yh 60 dB Bandwidth 5 20 4 dB 10 Spectral Lines Main Lobe Width 5 47 Spectral Lines Side Lobe Height 129 1 dB 100 0 dB The Blackman window works well in both the best and worst cases In the best case the main lobe is narrow with an extreme drop off after the main lobe In the worst case the main lobe width is wider but most of the energy is below 60 dB FFT Page 14 17 Blackman Harris Best Case Worst Case Frequency Response 60 dB Bandwidth 7 35 7 dB 8 54 8 dB Spectral Lines Main Lobe Width 7 10 Spectral Lines Side Lobe Height 122 3 dB 02 9 dB The Blackman Harris window profiled in more detail in the examples from the previous section is an excellent window in both the best and worst cases
435. rentiation Integration diff arg1 Options 2 2 Point Method 3 3 Point Method 5 5 Point Method t 1 1st Order Taylor t 2 2nd Order Taylor t 4 4th Order Taylor Examples RO diff AO RO diff t 2 A0 The Differentiation function calculates the change between points in arg as a function of the x axis For the Analysis element the change is calculated with respect to time a For the Frequency Analysis element the change is calculated with respect to frequency on This function requires that argl not be a single value The available options specify the number of points used to perform the differentiation the two point difference 2 the three point central difference 3 or the five point polynomial fit 5 or a Taylor differential The two point method uses the current and previous data points and is the closest approximation to an ideal differentiator The three point method uses the previous current and next data points and the five point method uses the previous two current and next two data points The Taylor differential methods are similar to the other methods with the advantage of additional logic to help reduce end effects at the beginning and end of the calculation The order of Taylor differential is expressed as one value less than the number of data points used for the calculation We recommend using one of the Taylor differential methods in most cases intg arg1 Options r Rectangular s
436. requency Measurements Configuring A Counter To Measure Frequency This example builds off our setup in the last tutorial In addition to the Pulse Count measurement we will measure the frequency of the same incoming signal 9513 Setup Configuration Connections zl 9513Chip F Source M Prescaler Binary C BCD Count On C Rising Edge Falling Edge FOUT Enabled Gate HiEdge Gate2 E ums E output Always Lo z Source Divider O a Registers r Counter Settings Load Register Hold Register mm Counter Count C Down 6 Up Function C Internal Pacer T C Reload C Load Only C Load Hold C Usage Frequency Cycle Once Repeat CMode 0 Format Binary C BED C Custom Special Gate C Disabled Enabled Cance Help Figure 9 9 9513 Settings for Frequency Measurement 1 Open the Counter Timer Settings by double clicking on the element 2 Set the Active column to Yes for channel A2 3 Press the 4u button or select the Device menu Hardware Configuration command 4 Press the 9513 Setup button 5 Select Counter 2 from the Counter list 6 Select the Usage radio button then select Frequency from the Usage list To measure the frequency of an input channel the counter counts the number of pulses which occur between successive rising edges on the Gate input This configuration assumes that the Gate input
437. ring units that produces the Output Minimum value Conversely the Input Maximum is the value going in to the sensor that produces the Output Maximum value From these values the Factor and Offset values can be calculated by setting up a simple matrix algebra calculation using the Y mX b equation Snap Master automatically performs this calculation for you in the Sensor Specifications table Sensor Database Sensor Assignments Table Columns Page 7 3 Sensor Assignments Untitled Beles File Edit View Settings Help EEG amp Big Tank a Ch Label ID Factor Offset Input Input Eng Output Output Output Kind Type Next Max Min Max Units Cal Date 17 Flow Turbine 11 20 96 iDisplace Encoder 5 29 98 Displace Encoder 5 29 98 celera Pi 8 8 000 06 360000 0 Counts Displace Optical 14 2 88 0 000 Nm 0 000 10 000 iCounts Displace Optical 7 30 38 J 360 000 Degrees 4096 000 4096 000 Counts H 19 6 97 1 360 000 iDegrees 360000 0 360000 0f Volts Displace Opitical 15 30 98 AD Balak CAR LAB BE2O 0 001 TAR 5721 1000 Badou Er 0 088 TORCEPS OUI 0 000 Dynamics E 0 001 0 000 360 000 iDegrees 360000 0f 360000 0t Counts Displace Optical 5 30 98 hd 11 10 57 3 23 36 PM Figure 7 3 Sensor Assignments Window The Sensor Assignments w
438. ring with each data point separated by a CRLF For example if the Block Size is 20 the DDE Out sends a string containing the 20 previous points when the 20th point arrives If the Block Size is not an integral multiple of the frame length the overflow points at the end of the frame are filled with a zero value The Block Size setting is used for all DDE communications within the DDE Out element If you include more than one DDE Out in the instrument each element can have a unique Block Size setting 6 3 Tutorial Receiving Data In From A Local Spreadsheet Building the Instrument This tutorial discusses how to create a simple DDE data link sending data from Microsoft Excel to Snap Master Of course any DDE aware Windows application can be used in place of Excel including other spreadsheets word processors databases or a custom application Before continuing the tutorial make sure that Excel is currently running If you do not have Excel you can use any application that sends DDE information For consistency this tutorial assumes that Excel is sending the DDE data i 4 DDE In B Display Figure 6 5 Instrument for DDE Out Tutorial 1 Create a new instrument with the command in the Snap Master workspace button or select the File menu New Instrument 2 Place the DDE In and Display elements in the instrument 3 Activate Pipe Mode with the button or select the Element menu Pipe Mode command 4 Connect the
439. rmat but the data is stored as interleaved floating point binary numbers Generally this type of data file will replay about four times faster than the Exponential file After the header the Frame Header is written with a TR which indicates a new frame the frame number a carriage return the date the frame was started in mm dd yyyy format enclosed in quotation marks the time the frame was started in 24 hour format of hh mm ss enclosed in quotation marks and a carriage return Immediately before the first data point in each frame a Sync Byte Hex value AA is written Each data point is then written as a four byte single precision floating point value Intel 80x87 format IEEE 754 1985 Each Sample Group contains one data point per each channel and the channels are written in ascending order Length 4 Channels Sample Points per Channel bytes Sample Group SG 4 Channels bytesO Byte Bit Range Description Assignment 0 to 4 all first channel s value Range 1 7e38 to 1 7e38 with minimum precision of 1 7e 38 24 bit floating precision 5to8 all second channel s value same etc all subsequent channels up to last same channel minus one SG 5 to all last channel s value same SG 1 If the data file contains frequency domain data then the data file contains both the magnitude and phase values for each data point For an FFT BLOCKSIZE of 1 the magnitude part is always followed by t
440. rom 0 to 31 To define which channels are processed in Snap Master select the channel or group of channels from the list Note that this does not turn channels on and off on the actual piece of equipment it is only used by Snap Master to determine which channels of data will be available to the other elements in the instrument Device The Device group contains the Configuration button and the Device List The Configuration button opens the Configuration dialog which specifies the settings for the computer s serial ports also called COM ports Finally the Device List selects the Configuration to be used for this element RS 232 String Assignments el Bj b fs New Open Save Insert Delete hd Inititialization ES Type Use String Inititialization NO jet us m Inititialization NO 60 0 uO ae Inititialization si YES 1Y44 g2220 1 ux 2 Start AYES ji00 00 01 0 00 0001 0 uO Start AYES ed CR 01 8 1 ux Stat i YES iYO10000 ux Start iYES 4 1 1 0 1 ux Start LLL ES UE MR 4 Instrument Response Format chich2ch3ch4ch5ch6ch7ch8 Multiple Query Delimiter Terminator iin Con Help Figure 10 2 RS 232 String Assignments The String Assignments dialog defines the different ASCII strings sent and received by Snap Master from the external equipment The string table specifies the strings used for specific events and if they are used by Snap Master in
441. round color sets both the back color for the plot as well as the colors of the virtual meter s bezel The bezel colors are automatically set to contrast with the Background color so the bezel is always visible Display Page 3 15 Channel Settings Dial Meter Channel Settings Dium Io End Angle feao i fsoo i Divisions fo El Range 10 po Needle Width NIS Colors C One Color Infinity To S Needle MB via EN C Iwo Colors 5 T5 Needle MIB oia NNI Three Colors 5 To Infinity Dia BN Preview Needle Figure 3 13 Dial Meter Channel Settings Appearance Angle Defines the Start and End angles for the dial meter d which range from 0 degrees to 360 degrees D 270 Divisions Specifies how many ticks appear in the meter and also defines where the meter values are displayed Range Specifies the corresponding data values for the Start and End angles Needle Width Specifies the width of the needle Colors Uses the same visual alarm methodology as the Digital Meter color settings by allowing up to three different color sets for the Needle and Bar on the dial meter Histog ram Plots Histogram plots are used in conjunction with the Histogram element to display data in terms of event bins instead of simply events Like the other plot types in Snap Master the histogram plot is updated as the data c
442. rs from the analog oscilloscope which continuously follows an analog voltage The advantage of the digital oscilloscope is that the data points collected can be used for further analysis as input to other computer programs The accuracy of the digital oscilloscope is based on the frequency of sampling data Outputs digital data from the computer to an external destination This feature is sometimes included on a plug in A D card A method of writing data from an A D board into a predefined memory block Information is transferred from the computer memory to a device on the bus while the processor does something else Also one of three methods of transferring data acquisition system measurements to computer memory the other methods being polling and interrupt Refers to either a floppy disk drive a hard disk drive or a RAM disk drive Reads data stored in a file on a floppy hard or RAM disk Can input files written in binary or exponential ASCIT formats and Snap Series files Writes data to a file on a floppy disk hard disk or RAM disk Can write files in binary or exponential ASCII formats or as a Snap Series binary file Displays data on the computer monitor The display options include y t and y x plotting and strip chart emulation Up to 10 plots per channel can be displayed on each set of axes Page A 4 DMA Channel DOS Drag Driver Dynamic Data Exchange DDE Dynamic Range Element Element Letter Error Mess
443. rsor displays all channels in the Cursor Data window When turned off only the primary channel is displayed When selected the item is visible by default When selected Auto Retrace is enabled by default When selected the default plot template settings are applied to all new plots created in the Layout The selected mode is used when a new Display element is included in an instrument Plot Technique The selected mode is used when a new Display element is included in an instrument Open the Status Bar Settings dialog box Operates the same as the Status Bar settings dialog in the Snap Master workspace Page 3 22 Cursor Data Table Retrace Mode Start Menu Snap Master User s Manual When you right click over the Cursor Data table the pop up menu contains a Settings command Selecting this menu command opens the Cursor Data Window Settings dialog Data Window Settings Cursor Data Table Table Height In Display Window Rows C Separate Window C Pixels o T Hide Window On Start r Cursor Link Movement C Relative Difference Time Aligned cot ee Figure 3 19 Cursor Data Window Settings In Display Shows the Cursor Data table in the Display window below the Window Command Bar and above any plots Separate Shows the Cursor Data table in its own window which always appears Window on top of the Display window Hide Window When selected the Cursor Data table is hidd
444. rument Page 4 6 Snap Master User s Manual Frames All Frames Replays all of the frames in the data file Frame Range Replays only the frames between the Start At and Stop At frames inclusive Replay Mode Specifies how the selected frames are replayed Continuous replays the entire selection without stopping between frames while Pause After specifies how many frames are replayed before stopping the instrument Restarting the instrument continues from the next frame until the Frame Range is exhausted in which case Disk In starts over from the starting frame For example the settings in Figure 4 3 are set to replay from frame 3 to frame 5 and pause after each frame The first time you run the instrument frame 3 replays then the instrument stops When you start the instrument again frame 4 replays then the instrument stops Another start replays frame 5 then the instrument stops If you restart the instrument after it has replayed all of the frames defined in the Replay Options dialog box then the Disk In element returns to the beginning of the frames defined in this case frame 3 Paced Replay When selected the data file replays at the original acquisition speed of the file This means that a five second frame in the data file takes five seconds to replay The Speed scroll bar adjusts the replay rate to faster or slower using the scroll bar Paced Replay works best with Standard Binary files acquired at slower rates under 1000
445. s Forcing Periodicity Page 14 25 The time delay for the first FFT result frame is equal to the sample rate of the input channel multiplied by the window width with a small amount of additional time required to process the data In this sense the FFT element does not produce real time results which would update the frequency domain calculation as each new data point is acquired but the results are presented after all points in the window are processed so they appear during acquisition The FFT element allows window widths between 2 and 16 384 points The width must be an even multiple of 2 3 5 and or 7 This means that it is as simple to specify a 1000 point FFT as a 1024 point FFT Odd valued window widths are not allowed so the width must always be divisible by 2 Window widths that are not an integral power of 2 take longer to process than widths that are multiples of 2 only The effect is more pronounced at higher window widths which is why a 16 000 point FFT takes longer to calculate than a 16 384 point FFT As illustrated when describing the best and worst case scenarios for the various window widths the number and location of the spectral lines has a tremendous impact on the accuracy of the frequency domain calculation This conversion of the continuous frequency spectrum into equally spaced spectral lines is the frequency domain counterpart of time domain sampling where time is separated into discrete slices which
446. s however a tradeoff The more channels Snap Master must handle the more horsepower needed to handle all of them As a rule you should use the fewest number of channels needed to complete your task Simply being able to delete a plot is not of much use if you can not insert a new one when you are interested in viewing more data In fact you can even view the same data in two different plots Display Overplotting Multiple Channels Page 3 31 Using the overplotting feature of Snap Master you can display up to 16 different channels of data on the same set of axes This is useful when comparing similar data sets 1 Select the Layout command Display Layout Ej sf E 4 amp Insert Delete Plot Settings Channel Settings Page Settings 0 Al Page Linked Tite On Plot Type Ch 1 Ch 2 Ch 3 Ch 4 Ch 5 Ch 6 1 No M vsTme D ee 01 LL s l1 H7 Ne TAT vs Time T f 2 i A f AQ vs Time TM CNN CUR Figure 3 28 Overplotting Display Settings 2 Move the selection box to the third row then press the Insert button E A new plot appears as Untitled 3 Notice that the default plot type is y vs t and that no channels are assigned yet 3 Move the selection box to the Ch1 column in the third row Click on the pull down arrow located in the upper left corner of the table and double click AO This pull down list is an important feature of all tables in Snap Master The content
447. s Channel at time f Page 3 10 Digital Meters Digital Meter Settings Snap Master User s Manual The Digital Meter plot type is also a time domain plot but only one data point is displayed at a time This plot type is useful for data that does not change rapidly such as temperatures or statistical values from the Analysis element For time channels with only one point per frame Digital Meter is the default plot type for the Auto Layout function Digital Meter Settings Title Digital Meter Iv Show Title v Use Default Sub Title I Show Sub Title r Plotting Technique r Fonts d ae E Item Title zx ettings Mode Rate 0 2 S N i Label z Appearance Location V Default Locked Rows Default C Manual i B Columns Default C Manual i B r Colors Item Text Channel C Label Number Background Data Scaled C Unscaled o elect Font Visible v Channel v Units Select Color Cancel Help Figure 3 7 Digital Meter Settings Plotting Technique Mode Auto mode displays the most recent data value when an update occurs Interval displays the data at every time interval specified by the Rate setting similar to the Skip mode for a Y T plot Average displays the average data value for all points in the previous interval Rate Specifies the update rate for the digital meter in seconds Similar to the Points setting for a Y T plot Appearance
448. s if the title for each Display page uses the Snap Master defined name or the user defined name When Default Title is Yes the window is named Display Page where the is the page number When Default Title is No the contents of the Title cell defines the window name User defined title for the page When set to Yes Snap Master arranges each plot automatically to provide the maximum size for each set of axes When set to No the number of Rows specified is used User defined number of rows for the page Entering a value here automatically changes Auto Rows to No To have each graph appear in a single row set the number of Rows to 1 When set to Yes Snap Master arranges each plot automatically to provide the maximum size for each set of axes When set to No the number of Cols specified is used User defined number of columns for the page Entering a value here automatically changes Auto Cols to No To have each graph appear in a single column set the number of Cols to 1 Display Cursor Menu New Cursor Page 3 25 Cursors are used to view the actual data values for a specific point or the relative difference between two data points When you are placing a cursor the mouse pointer changes to Move the center of the mouse pointer over the waveform you wish to place a cursor on and press the mouse button The data for the cursor appears in the Cursor Data window If the data you clicked on is not available in memory
449. s of this list depend on the current position of the selection box We will use the list often in these tutorials to give you an idea what options are available 4 Move the selection box to the Ch2 column in the third row and select channel A1 Use the pull down list to specify the channels as done in previous steps These additional channel columns are the overplotted channels 5 Press the Close button Page 3 32 Snap Master User s Manual Strip Charts and Y X Plots 6 Press the button E Display Page 1 of Eile Edit View Settings Start Layout Cursor Help rs AD vs Time Frame s Time Sec Time Sec AD vs Time Frame 1 Time Sec 2 Stopped instrument CASM DEFUSER EXAMPLE1 INS Figure 3 29 Overplotting Channels The new set of axes contains the same information from the top two graphs plotted simultaneously However notice that the colors and line thickness are different from what you specified for the original two plots of AO and A1 This is because the colors and line type settings apply only to a specific plot and not globally for all plots Use the Channel Settings dialog box for the channels in the third plot to change the colors and line style Now that we have looked at some ways to change the Y T plots we can now look at the other plotting types in the Displ
450. s the color for the background of all default bar plots If a user defined picture is included the Background color setting does not change the background color of the picture as it appears in the Display Bar Meter Axis Settings Label 0 Volts Iv Show Label v Default Label r Scale TUNIS Major Divisions Iv Default Scale Divisions 4 x Tick Mark C N Top 10 Volts Ue Show Axis Values Bottom 10 Volts G Min Max C All I Show Axis Divisions 4 H Tick Mark C None Ee J Cancel Help Figure 3 9 Bar Meter Axis Settings Even though the bar meter displays a single value it does so in relation to an axis The Bar Meter Axis Settings dialog operates in the same fashion as the X Axis or Y Axis Settings for a Y T plot The direction of the bar meter which is set in the Picture Settings dialog determines if the scale is measured from Top to Bottom Vertical or Left to Right Horizontal Display Channel Settings Picture Settings Page 3 13 Bar Meter Channel Settings comet Ho Figure 3 10 Bar Meter Channel Settings The Channel Settings for a bar meter defines the fill color for the bar There are no alarm conditions for the bar meter so only one color needs to be defined if you want to include special alarm displays in a bar meter try including them in a user defined picture Any channels highlighted in the Channel list are set to
451. s the factor You can compensate for the factor by multiplying the value by 100 using either the Analysis or Sensor elements Page 9 14 Snap Master User s Manual 9 4 Overview Of The 9513 Source Gate and Output SOURCE OUTPUT GATE 9 13 Counter Inputs Outputs and Registers The Am9513A chip from Advanced Micro Devices Inc provides a variety of counting sequencing and timing functions Most dedicated Counter Timer hardware uses this chip to perform such tasks as frequency synthesis pulse generation event counting duty cycle measurements and many others Because the Counter Timer hardware is heavily influenced by the operation of the 9513 this section presents a brief overview of the 9513 and its nomenclature For a more comprehensive discussion of the chip s capabilities we encourage the user to refer to the Am9513A System Timing Controller description available from Advanced Micro Devices Inc 800 538 8450 or an AMD dealer Each counter has a Source Gate and an Output signal as indicated by the thick lines in Figure 9 13 These signals are available for each counter at the termination panel for the Counter Timer hardware The Source input is the signal used to determine when to perform a counting action The count occurs on either a rising or falling edge There are sixteen different signals that can be used as the Source the five SOURCE inputs from the termination panel the five GATE inputs from the
452. second If the test does not go as expected make sure you have the proper signal connections and software settings If the Status Log appears with an ERROR entry follow the remedy listed If all else fails verify the hardware Configuration Analysis and Frequency Analysis Page 12 1 Chapter 12 Analysis and Frequency Analysis IAWOUUESDIICI C C R H LOMA 12 2 Functions Leer eee eee eee ee seen enses sets setas stessa etos s essa esses senes senes esos sess sess stesse sess se sns se sense ees sse esna a a 127 11 12 3 Equation Syntax eee eee eee ee eese tees sees seen sets set en sse en sse sns sess sets sess sse sns se sns se sons esses eene se snssesssesesseessseesseees2s 12 26 12 4 Tutorial Adding Two Channels eeeeee eese eese eese sees eee en netos s stesse ens s esos sess seen see ens sess se sossesesseessseeeseees 12 28 12 5 Tutorial Performing A Block Average eese eene eee e eese nenne einen sse ens se sns sess sees se eens se snssesessesesseeesseesesees 12 32 12 6 Tutorial Finding When An Event Occurs eese eee sees eene seen etes seen sse ens sess s eese s senes ess se sossesesseessseesseeess 12 34 12 7 Tutorial Integrating Over A Specific Range Of Data eeeeeee eese sees eese essen senes s seessnsseenseeeseeeises 12 3 7 12 8 Tutorial Defining Your O
453. see Disk In Rectangular Window 14 15 14 16 14 23 14 26 Registration 1 3 Re Letter Mode 2 2 2 5 Replay Options 4 5 Retrace 3 2 3 20 8 9 Retrace Mode 3 22 Riemann Window 14 23 RMS 12 17 Running 12 17 Root Mean Square 12 17 Round 12 25 RS 232 2 11 8 17 10 1 Configuration 10 7 Delimiter 10 5 10 8 Hydra Example 10 8 Initialization 10 4 Multiple Query 10 2 10 9 Query 10 4 10 5 10 9 Response 10 5 Response 10 9 String Assignments 10 3 String Table 10 4 10 8 Termination 10 5 Terminator 10 8 S Sample Instruments 1 1 Sample Interval 10 6 10 9 Sample Rate 2 16 2 20 2 22 5 9 8 5 12 26 Asynchronous 8 4 Scatter Plots 3 9 Scroll Bar 3 2 3 17 Secondary Cursors 3 26 Sensor 1 7 2 11 3 8 3 10 7 1 7 7 Automatic Calculation 7 4 7 8 Database Configuration 7 7 Out Of Calibration 7 3 7 12 Sensor Assignments 7 3 7 11 Sensor Calibration History 7 6 Sensor Specifications 7 4 7 8 SHARE EXE 1 7 7 8 7 10 Signal Conditioner 2 11 Signal Conditioning 7 1 7 7 Sine 12 13 Inverse 12 14 Sine 3rd Power Window 14 24 Skip Rate 3 26 Slope 3 39 12 15 SMARTDRVYV 4 2 4 11 Snap Master User s Manual Smooth 2 11 SMSTART 1 8 Snap Calc 12 4 12 7 Spectral Analysis 12 16 Spectral Lines 14 25 Square Root 12 13 Standard Binary Data Files 4 2 4 19 Standard Deviation 12 18 Standard Mode 1 7 1 8 Start 2 9 State Variables 13 2 13 4 13 13 Stationary Plot 3 6 Status Ba
454. see data for channel AO every frame but data will be displayed for channel BO the output of the MultiFrame element only on the fifth frame 8 Press the OK button to close the MultiFrame dialog box 9 Open the Display window then open the Display Layout dialog box with the Layout menu Display Layout Delete Plot Settings Channel Settings Page Settings Figure 15 37 Display Layout Depending on how you have Auto Layout configured you may need to delete the plots for channels Al A2 and A3 Highlight the plots you do not need then press the Delete button g Y Axis Settings Label B0 Volts Axis Type Linear C dB 10x C Logarithmic C dB 20x T Multiple Y Axes Current Axis Location x 0 x FREE T Default Scale Minimum 30 Volts Maximum 30 Volts Format Default zi Significant Digits i 3 Iv Show Label IV Use Default r Major Divisions was Diis F8 Show As Horizontal Grid C Tick Mark C None Iv Show Axis Values Minimum and Maximum C All Major Divisions I Rotate Axis Values r Minor Divisions Minor Divisions 2 4 Show As C Tick Mark None Cance Help Figure 15 38 Y Axis Settings for MultiFrame Output Before we close the Display Layout we need to configure the Y Axis for the plot of BO with a minimum of 30 and a maximum of 30 10 Position the selection box in the second row
455. see eene seen sse se essseseeeseseesssseeees 6 21 One of the major advantages of Windows is a number of integrated methods for different applications to communicate and share information The most common methods are the Clipboard and Dynamic Data Exchange DDE Both of these methods are supported by Snap Master Clipboard The Clipboard is the focal point for all data exchange between applications When you select the Copy Cut and Paste commands the Clipboard becomes the holding place for the information For the Copy and Cut commands the currently selected information is sent to the Clipboard while the Paste command places the contents of the Clipboard in the current application The Clipboard supports the basic types of Windows information text and pictures also called bitmaps For example you can select the Edit menu Copy command in the Display window to copy the contents of the Display which is stored in the Clipboard as a picture When you Paste the picture in another program such as a word processor spreadsheet paint program etc the Clipboard sends the stored picture to the application requesting it This makes it easy to include information from a number of programs into a central document In Windows 3 1 the Clipboard contains only one item at a time However in Windows for Workgroups the Clipboard metaphor is extended to the Clipbook The Clipbook stores multiple Clipboards as separate pages similar to a scrapbook W
456. selection box in the first row Equation Definition column type RO AO AI then press ENTER To continue the tutorial skip ahead to Step 14 2 Press the button or select the Builder menu to open the Equation Builder Analysis Equation Builder Line 1 Equation Ro A0 A1 E Quick Functions I x z Pea Or Jofre L t j A05 book range Define Function Builders 4 Function Absolute a Arithmetic Addition Trigonometric And Calculus ArcCosine Statistical ArcSine Filters T ArcTangent x Syntax argument argument2 Description Adds each point of argument and argument2 Previous Line Cancel Help Next Line gt gt Figure 12 11 Equation Builder with Addition Equation The first item needed in the equation is the result channel We have two options for entering the channel either typing it in manually or using the On Screen Keypad To illustrate its functionality these instructions show how to open the On Screen Keypad and use it to define a channel Page 12 30 Snap Master User s Manual 3 Position the mouse pointer over the Equation edit control and press the right mouse button to open the On Screen Keypad Channel R 0 o Value sista c3 Figure 12 12 On Screen Keypad 4 Select the Channel radio button 5 Select the letter R from the list box 6 Press the number 0 on the On Screen Keypad 7 Press the OK button to c
457. sing multiple subroutines you must end the previous one with an End Sub before declaring a new subroutine The Command element produces two types of variables result channels and state variables Result channels are variables that are used by the Digital Out and D A element to set the values of digital and analog outputs State variables are internal to the Command element and cannot be referenced by other elements Neither result channels nor state variables can be stored to disk with the Disk Out element This is because the Command element treats all incoming data as a continuous frame there is no Frame Duration setting with the Decision Rate in the Command Settings dialog One exception to this rule is you can use the Digital Meter plot type of the Display element to display Command element result channels but not state variables A result channel is written with a leading apostrophe just like the Original Syntax in the Analysis element The value of a Command result channel can be set to either a constant or the value of another data channel You can not perform any arithmetic on Command element result channels The element letter used for a Command element result channel must be the same as the Command element letter in the instrument If you try to use a different element letter an error appears in the equation table A state variable is used only within the Command element to store data that is not available from other data channe
458. sity is G column S is the instantaneous amplitude spectrum of a S i is the complex conjugate of S and df is the frequency resolution Page 14 8 Cross Power Spectrum Cross Power Spectral Density Coherence Function Snap Master User s Manual The Cross Power Spectrum determines the average power common to two signals which are listed in the Ch1 and Ch2 columns This function is identical to the Auto Power Spectrum In order to perform the Cross Power Spectrum function the two channels being analyzed must have the same frame characteristics The result units are the products of the units such as volts or volts psi This function is identical to the Auto Power Spectrum except that two different channels are used to calculate the amount of power common to both channels If the same channels are specified in Ch1 and Ch2 then the Cross Power Spectrum is equal to the Auto Power Spectrum of the channel The Cross Power Spectrum is the frequency domain equivalent of Circular Cross Correlation in the time domain The mathematical description for the Cross Power Spectrum is avg S i where b the output is the channel listed in the Ch1 column a the input is the channel listed in the Ch2 column S is the instantaneous amplitude spectrum of b and S is the complex conjugate of the instantaneous amplitude spectrum of a The Cross Power Spectral Density function calculates the normalized power contained in two
459. skip step 2 2 Select the Options menu Default Settings command to open the Default Settings dialog Display Defaults Auto Layout Options Vv Gn IV Command Bar One Channel Per Plot IV Status Bar C Overplot Same Element Letter Scroll Bar C Overplot Same Channel Number v Auto Retrace C Overplot Channels With Same Units I Apply Defaults For New Plots Overplot l Use Multiple Y Axis Retrace Mode I Warn If Different Units C Buffer Retrace Max Channels n C Full Retrace T Delete All Plots Before Auto Layout plot Technique T Confirm Delete Before Auto Layout C All Points Cursors l Select All Secondary Channels Automatic Cancel Help Make sure the On check box is on the One Channel Per Plot setting is selected and the Delete All Plots Before Auto Layout check box is turned on When you are done press the OK button If four plots do not appear select the Options menu Auto Layout command 3 Press the button or the Start menu command Page 2 20 Snap Master User s Manual Display Page 1 Eile Edit View Settings Start Layout Cursor Help PIG JE Joe dcn AD vs Time olx Al vs Time Frame 1 A0 Nolts Se Time Sec A2 vs Time Time Sec 3 A3 vs Time Frame AQ Nos Time Sec Time Sec Figure 2 16 Display Window That s all
460. so called FBDF for short and Exponential In addition Snap Master can import and export data in a number of generic formats including Plotter and Comma Separated Variable or CSV files Each format has its own advantages and there are some general rules to follow when selecting the proper format for your instrument The difference between the native Snap Master data file formats and the generic file formats is how the file is organized Snap Master native files use a format which contains a header and separate data frames The header provides information on the data file that is used by the Disk In element to accurately recreate the data for post processing Generic data files do not contain this header and the data is presented as one large series without any frame divisions Text based data files including the Exponential ASCII Plotter and CSV formats files store the data as a standard ASCII text file that can be read by most programs Also the file can be read by humans using the DOS TYPE command The main advantage of this universal data type is that the file can be read by most programs including word processors spreadsheets and databases There are two disadvantages when using an ASCII file format the files require a large amount of disk space up to eight times more than a binary file and the files take proportionally longer to write to disk up to ten times longer Therefore ASCII files should be used when the data is acquired
461. solution s Resolution of arg1 Points Per Frame p Frame duration in points of arg1 Frequency Range t Maximum frequency in Hz of arg1 pi Example S0 pi The Pi function returns a single value of the trigonometric constant 7 3 14159265359 pulse Example RO pulse The Pulse function returns an array of points with a value of at the middle point in the frame and 0 elsewhere This function is often used in conjunction with the FFT element to find the frequency response of a filter or scaling window 12 3 Equation Syntax Entries in the equation table fall under one of four categories equations references DDE links or user defined functions These are characterized by the following keys e Equations start with a result channel defined using the standard element letter channel number convention followed by an equal sign and the equation definition e References do not contain an equal sign and are used for frequently used equation fragments or constants To include a reference in another equation use the symbol and the line number of the reference e DDE links are contained in curly brackets and represent a cold link DDE links can be used for constant values or to define the start and end points for the Range function The DDE data can come from a variety of source programs such as a spreadsheet user written program or the Display Cursor Data table e User defined functions always start with the keyword Defi
462. splay window it appears below the Command Bar and above any plots which are resized to fit the additional window When the table is in its own window that window will always appear on top of the Display window and it can be repositioned anywhere on the screen The following list describes each of the columns in the Cursor Data window Column Description Marker Label The name of the marker For cursors this field is blank Ch The channel associated with the cursor or marker Linked Specifies the linked cursor or marker group for this item Up to 8 link groups can be defined When any cursor or marker included in this group is moved all cursors and markers in this group moved according to the Cursor Link Movement setting which is set in the Cursor Data Window Settings dialog Pt The location of the current data point in relation to the frame You can poke these values to the Cursor Data table using DDE Page 3 20 Settings Menu Snap Master User s Manual X Value The X axis value of the current data point You can poke these values to the Cursor Data table using DDE Units The X axis units of the channel Y Value The Y axis value of the current data point Units The Y axis units of the channel Channel Label The label of the channel which the cursor or marker is tracking Type For a cursor lists either Abs for Absolute or Rel for Relative For a marker lists Mrk Slope For relative cursors the slope between
463. spond to the settings in the header then the file will not be replayed correctly The file header for a Snap Master data file consists of two parts the introduction and the parameter list The introduction contains an initialization line and the user defined comments for the data file The parameter list gives the parameter variables used in the data file and the values for each parameter Page 4 16 Snap Master User s Manual Initialization Line The first line in the file header starts with Snap Master Data File a comma and a number specifying the number of parameters appearing in the data file including the Comments line Comments The next line s contains the user defined comments which are entered in the File Comments field of the Disk Out dialog box Comments are preceded by COMMENTS a comma the number of characters in the string a comma and an equal sign and the text string enclosed in quotation marks The format for the available parameters for Snap Master data files are listed in the following table All values of x specify the character length of the value or string to the right of the equal sign DATES 12 TIME 10 ACT FREQ x ACT SWEEP x NCHAN x CHANS x NUM POINTS x CLOCK UNITSS x FILE TYPE x Exponential Standard Binary Fast Binary INTERLEAVE FACTOR x CONVERSION POLYS x String that specifies the date that the
464. ss the left mouse button and release Located in the upper left corner of the window Double clicking on the close box exits the application Snap Master element that performs actions based on decisions phrased using IF THEN syntax Area at the top of a Snap Master instrument window where the user can enter text about the instrument A measure of an instrument s ability to ignore or reject interference from a voltage common to its input terminals relative to ground CMR is usually expressed in dB decibels Software that can perform more than one task simultaneously This terms refers to the hardware and software set up They must correspond The hardware should be changed first and then the software configuration file should be changed to match the hardware changes Hardware that counts digital events or measures the time difference between digital events A cursor allows the user to determine time and amplitude in engineering units data while viewing the waveforms Abbreviation for Digital to Analog Conversion Reverse of A D Converts digital data into an analog signal which is output through a plug in D A card This feature is included on some types of A D cards Glossary Data Acquisition Data Acquisition Module Data Pipes DDE Dialog Boxes Differential Digital Digital In Digital to Analog Conversion Digital Oscilloscope Digital Out Direct Memory Access DMA Disk Drive Disk In Disk Ou
465. ssoasessassabassessabacscsuabesecssesscsessesssses 11 1 D A Sett ngs 3 eoe d eee eed eof edic pete a peret ee stolis 11 1 n 11 3 11 3 Tutorial Outputting Analog Data crece e eee eese eee eene netten e eset ttn aset enses etta esee tense sese enasseno 11 4 Building the Instr ment ette tete cete e tee eee bea ee tee ave ede ten 11 4 Configuring the A D Demo nde bud pP EE deti e Ue peteret 11 5 Configuring the A D Hardware eee emere erepto ierit eee eh ee gea 11 5 Configuring the D A iiie mb ain ended en E eet eder eret ide ees 11 6 Running the Instr mient e ceteri eee et ee tee ee Eee unen ERE ee RAT Le 11 7 11 4 Tutorial Outputting Digital Data 1 eeeeee esee eese ee ette eene eene esee eene sett tna eset tes eset enses eet ens se eno 11 7 Iullinpau sunu MEE 11 7 Configuring the Digital Out Element enne neen neret nenenenen neret eene 11 8 R nning the Instr merit 2 ee ette ete mete ete te tete ete ete tete een eden 11 8 Data Analysis Chapter 12 Analysis and Frequency Analysis ZAEMSLS LI M o uL E 12 1 Erequency Analysi ee are NR CR Hee RR AM e Ce ERRANT cie e ty 12 1 Command Bar nana Ran a DARIN ERRARE A A IA 12 2 Table Columrs ie ne eI PORRO ERO PORE RE ees 12 2 Quick Function Refererice 2 ole de lea e d e a ere ete Eee i e HER EUER A 12 3 Enr
466. st example we will utilize the special network communication features of Snap Master version when bulding our client instrument Building the DDE Client Instrument TI 4 DDE In B Display Figure 6 18 Instrument for DDE In Tutorial This instrument is built on the computer intended as the DDE data client Multiple clients can access the data from a Snap Master DDE Out element simultaneously 1 Create a new instrument with the command in the Snap Master workspace button or select the File menu New Instrument 2 Place the DDE In and Display elements in the instrument 3 Activate Pipe Mode with the button or select the Element menu Pipe Mode command 4 Connect the DDE In element to the Display element 5 Turn off Pipe Mode with the button or select the Element menu Pipe Mode command 6 Save the instrument with the button or select the File menu Save Instrument As command Save the instrument as DDEIN Configuring the 1 Open the DDE In Assignments by double clicking on the element DDE Conversation 2 Set the DDE Conversation settings with the button or select the Settings menu DDE Conversation command Page 6 22 Setting Up The DDE In Channels Running the Instrument Snap Master User s Manual DDE Client Conversation p Data Source Local Machine Network DDE Computer Name SPARKY Browse l r Server Application Snap Master Instrument DDEBLOCK zi
467. stogram Tutorial When you run the instrument the data in the plot of BO appears as data comes in from the A D Demo The Y axis shows the number of data points contained within each voltage range In this case each bin represents a 2 volt range from 10 to 10 Volts This is due to our settings in the Event Counting and Sorting element Total Range Maximum Minimum and the Range per Bin Total Range of Bins If you were to count the total number of data points there would be 200 because the Sampling Rate of the A D Demo is 100 per second and the frame size is 2 seconds Page 15 22 15 9 MultiFrame p Snap Master User s Manual This element is included with both the Waveform Analyzer and Frequency Analyzer Modules The Multiple Frame element performs a running sum or average across a specified number of data frames The input data can be either time based or frequency based The output is a single channel channel 0 using the element letter of the MultiFrame element with the same sample rate and number of points per frame as the input channel Multiple Frame Calculation Input Channel Calculation Type Time Sum x7 5 C Frequency C Average Kanes Output Rate S ll PT Figure 15 33 Multiple Frame Calculation Dialog Box Input Channel Specifies either the Time or Frequency domain channel being analyzed Note that the contents of the Channel list only contains channels of the specified type Fra
468. stored in the CLC file or the FCL file for the Frequency Analysis element If they are different a message box will appear asking you if you want to change the function defaults to the ones stored in the file In order to duplicate a previous test exactly you should accept the changes by answering yes Analysis and Frequency Analysis Frame Characteristics Page 12 9 Result Element Frame Characteristics OLIP Elmt Sample Rate Duration of Points X axis Label X axis Units P 00 000 10 000 UC Ec A i 100000 10000 1000 Time 568 aia Cancel Help Figure 12 7 Frame Characteristics Table Table Columns Elmt Sample Rate Duration Resolution Freq Range of Points X Axis Label X Axis Units Element letters assigned by Analysis element You cannot enter new element letters in this table you must assign new result elements using the equation table Displays the sample rate for the Analysis element Displays the length in seconds for each frame of data for the Analysis element Displays the frequency resolution for the Frequency Analysis element Displays the maximum frequency for the Frequency Analysis element result channel Displays the number of points in the each frame of data Specifies the Label used by the X Axis For the Analysis element the default label is Time For the Frequency Analysis element the default label is Freq
469. strument is running These options are useful for reducing the amount of data actually written to disk Channel List Specifies which channels to write to the data file If you are using the Fast Binary data file format you must save all channels from any element letter you are saving For the ASCII file formats you can only save data from one element letter Page 4 10 Write File Comments Disk Out Defaults Snap Master User s Manual To save all of the channels turn on the All Channels check box If you want to select channels that are not continuously listed turn off the All Channels check box then press the CTRL key while selecting the channels with the mouse button Frame List Specifies which data frames to save To save all frames in the instrument turn on the Save All Frames check box If you want to specify a list of frames to save turn off the Save All Frames check box enter a number in the Frame edit control then press the Add To List button You can add as many frame numbers to the list as you would like To delete a frame select one from the list box and press the Delete From List button Write File Comments Internal Pacer 100 Hz Cancel Help Print Figure 4 9 File Comments Dialog Box By pressing the File Comments button in the Disk Out Settings dialog box you can enter notes about the data files Useful information that might be included in this field are special conditions in which the test
470. t esssssssesseeeeeeeeeneen nere nnne nnne enne nnns Appendix A Glossary Appendix B Bibliography Appendix C Aliasing Appendix D DDE Commands and Parameters Appendix E PC Computer Information Appendix X Index Page xi B 1 C 1 Getting Started Page 1 1 Chapter 1 Getting Started INL CE C EST 1 2 Technical Support ex 1 3 System Requirement crece eee eese ee ette esee esee tena eset ens esee ense set tiosat osons sosa sosu eeo sesso sonos see sosse ses sessesesseseseesssses 175 1 4 Installing Snap Master 4 Lees eee eee sees essen esee nete s sten sse Eae sess E seen sten sse sos se sess esses eene se eose ssis 1 0 1 5 Computer Configuration 1 eee eee eee eese eene eene stesse ens s etse tss e tens s tens s esos se sess esses senes esee sess se sesseesnseesssseseseee 1 0 1 6 Start Using Snap Master eee eee eee sees seen seen netos stessa se sns sess sets sets sten ss esos se sess esses esses assesses nessies 1 9 1 1 Welcome Sample Instruments Data Acquisition System Congratulations on purchasing Snap Master for Windows the new generation of PC based data acquisition analysis control and display software from HEM Data Corporation Snap Master combines advanced data acquisition and storage capabilit
471. t Display Page A 3 The collection and recording of information Snap Master collects the information using a variety of input sources and records the data to disk when the Disk Out element is included in the instrument Snap Master module which performs data acquisition functions Data can be acquired using a plug in A D board or external hardware Contact HEM Data for a list of currently supported hardware Data pipes transfer information between elements The elements are said to be connected with data pipes To connect elements together change to Pipe Mode which is located in the Element menu see Dynamic Data Exchange Used to set up element parameters and to display messages In order to continue you must respond by pressing a pushbutton Positive and negative inputs each go into separate amplifiers which improves the noise reduction Opposite of a single ended input Requires twice as many amplifiers as single ended inputs A signal which has distinct states Digital computers process data as binary information having either 1 or O states Receives digital data from an external source This feature is sometimes included on a plug in A D card The process of changing discrete data into a continuously varying signal Common uses are to present the output of a digital computer as a graphic display or as a test stimulus Equipment used to sample the input signal at discrete time intervals and visually analyze data Diffe
472. t a cursor or marker Because there is no data associated with the text a corresponding item does not appear in the Cursor Data table Text Settings Marker Settings Labet Maker ss S r Label Appearance Background Transparent xl Label Font Position Horizontal C Left C Center C Right Vertical Top C Center Bottom Symbol Appearance Fill Solid zi Symbol Color Shape C Rectangle Ellipse Height 3 Width 3 Skip Every fs points Delete Marker OK Cancel Help Figure 3 24 Text Settings Dialog Box To edit the Text item double click on it in the window so the Text Settings dialog appears The Label Appearance and Label Font work the same as for a marker As part of the text item you can include specific information about the elements in the Snap Master instrument or information from another DDE enabled application To disable the DDE Request select the None radio button The Show check boxes determine if the name of the information is included in the label When Snap Master is selected as the DDE source use the Element list to see all of the elements included in the instrument When you select an element the available DDE parameters appear for the element refer to Appendix D for more information on the available DDE Parameters for each element Using this mechanism you can request information from any element such as the data file name from a Disk In element the Sample Rate for
473. t command We need to assign a channel to one of the D A channels The data values of this channel are used to set the value of the analog output Again make sure you have a physical connection on the hardware s termination panel for the output of D A channel 0 or channel 1 to A D channel 0 or channel 1 1 Open the D A Settings by double clicking on the D A element D A Settings r Pacing r Channel Assignments Type Software zl Location C intemal C External Driving Channel a Available Channels Output Rate Default Manual Hz _Sutput Ranges Ranges r Device p is Pisi Slot 3 DDA4 F zl Duration j Sec T Status Messages C of Points y O Configuration Iv Stop On Error Cancel Help Figure 11 7 D A Settings 2 Set the Input channel for Output 0 to AO This assigns the data from channel AO the 0 5 Hz sine wave from the A D Demo to output channel 0 If your D A hardware does not have a channel 0 use channel instead 3 Press the OK button to close the D A Settings 4 Save the instrument with the button or select the File menu Save Instrument command Data Output Page 11 7 Running the Before starting the instrument make sure you have a physical connection on the hardware s Instrument termination panel for the output of D A channel 0 or 1 to A D channel 0 or 1 1 Press the button or the Start menu co
474. t may come from within the equipment or from a special Snap Master pacer If the equipment automatically produces a new reading the Multiple Query checkbox in the Strings dialog which specifies the ASCII strings used to communicate with the equipment should be turned off and the Sample Interval value should be the rate at which the equipment updates To use Snap Master as the pacer then the Multiple Query checkbox should be turned on and the Sample Interval value specifies how often Snap Master sends out a Query string Refer to the Strings section for more information RS 232 String Assignments Page 10 3 Because many RS 232 instruments communicate at very low rates the pacing value for the RS 232 element is sometimes specified as the interval between samples rather than as a sample rate Any interval greater than zero will be accepted as a Sample Interval However this does not mean that Snap Master will always read data from the instrument at exactly this rate The performance of Snap Master depends on the speed of your computer the speed of the serial communications the number and types of other elements in the instrument etc Some experimentation may be required to determine the performance range of Snap Master using this element Channels The Channels list contains the channels specified in the Format line from the Instrument Response Format of the Strings dialog The RS 232 element supports up to 32 channels of data numbered f
475. t menu are Opens the Command Settings Cos Checks the equations for errors The button says when the table check is successful Like the Analysis element the Command element uses an equation table where all active equations are run Equations are turned on or off in the Run column A description for each column is listed below Symbol Description Indicates the line number of the equation Up to 100 lines of comments or equations can be written Run Indicates if the Equation Definition contains a comment When the field contains an X then the contents of the Equation Definition are not processed Equation Place where the equation statement is defined Each equation can be Definition approximately 250 characters long Page 13 2 13 1 Menu Commands View Auto Indent Auto Case Settings Command Seitings Snap Master User s Manual Please refer to Chapter 2 for a description of the common menu commands When selected the Command element indents the equation lines based on their position within a nested If loop This setting does not affect the results When selected the Command element automatically capitalizes the equation lines This setting does not affect the results Decision Rate Initial State Variable Values Command Settings Decision Rate 10 Hz Initial State Variable Values PeakCount Variable Name Initial Value PeakCount Ha X ValleyCount ei
476. t occurs and the time when the count value is read which is on the order of a few mS If this delay is negligible then Software latching is recommended 9 2 Tutorial Measuring Pulse Counts Building the Instrument This tutorial counts the number of incoming pulses using Counter Timer hardware based on the 9513 chip In this example the Counter Timer input element is used to sample the incoming pulses as a function of some external digital pulse event which is sometimes associated with some external physical unit such as degrees or revolutions CTMIN A Device 2 B Display DAS CTM D5 A Figure 9 3 Instrument for Counter Timer Pulse Counts Tutorial 1 Create a new instrument with the button or select the File menu New Instrument command in the Snap Master workspace Counter Timer Configuring A Counter For Pulse Counting Page 9 7 2 Place the Counter Timer and Display elements in the instrument 3 Activate Pipe Mode with the button or select the Element menu Pipe Mode command 4 Connect the Counter Timer element to the Display element 5 Turn off Pipe Mode with the button or select the Element menu Pipe Mode command 6 Save the instrument with the button or select the File menu Save Instrument As command Save the instrument as PULSE 1 Open the Counter Timer Settings by double clicking on the element A Device 4 Counter Timer Settings Untitled Brie File Edit View Settings Device Help
477. t one of the frequencies does not fall on a spectral line We will still look at our 100 Hz signal but we will add a 200 5 Hz signal as well The 200 5 Hz signal falls directly between the spectral lines at 200 Hz and 201 Hz so we will not see a perfect representation of the signal but we should know that something is happening in that frequency range 0r fi Tad Blackman Harris Rectangular hi 20 eT LU LL Ex 60 Triangular SAIL ll 100 4 LL 1 1 1 1 1 1 L 1 Ex j 80 100 120 180 200 220 140 160 Frequency Hz Figure 14 6 Response of FFT Windows on Spread Out Frequencies Around 100 Hz we see the same type of response for the Blackman Harris and Triangular windows as when there was a single frequency However the Rectangular window does not have as much attenuation as before only about 50 dB compared to the 100 dB for the single frequency signal At around 200 5 Hz the width of the main lobe is much wider which affects all other frequencies in the spectrum As a result when the frequency being measured does not fall directly on a spectral line the Rectangular window loses its accuracy With the 200 5 Hz signal falling between spectral lines the benefit of the Blackman Harris window becomes evident Even in this worst case scenario the width of the main lobe is only 10 spectral lines and the closest side lobe is 92 9 dB down from the amplitude of the main frequency The larger width of the main lobe
478. t to the TCLinear element and the TCLinear element to the Display element 5 Turn off Pipe Mode with the button or select the Element menu Pipe Mode command 6 Save the instrument with the button or select the File menu Save Instrument As command Save the instrument as MULTFRME Utility Elements Configuring The Wave Generator uj Wave Generator Untitled Fie Edit View Settings Help ej e A lom espe S DM iNo ine 10 000 Sec Voltage Yes Output Active Waveform Stage Stage Channel Channel Channel Length Units Label Units ee S a A Edit current frame acquisition settings 11 11 97 11 29 36 AMI Figure 15 11 Wave Generator Settings 1 Open the Wave Generator Settings table Page 15 9 2 Activate the first channel by selecting the first row Active column and selecting Yes from the drop down list 3 Open the Frame Settings dialog by pressing the button in the Command Bar or selecting the Settings menu Frame Settings command Frame Settings Sample Rate 100 7 Sec Frame Length Duration 10 Sec C of Points 1000 fH points Number of Frames C Continuous Stop After fI E frames ae een n Figure 15 12 Wave Generator Frame Settings 4 Set the Sample Rate to 100 Hz 5 Set the Duration to 10 seconds 6 Select the OK button to close the Frame Settin
479. tDigits instrument instrument instrument instrument instrument instrument instrument Plot XAxisMajorDivisions instrument Plot XAxisShowMajorDivisions instrument Plot XAxisShowAxisValues Plot XAxisMinorDivisions Plot XAxisShowMinorDivisions instrument instrument Exec Req Poke Exec Req Poke Y X Scatter RA ARRAS NS X Format string string string string string string single string Format string string string string string string string string string string string string string integer string string integer string Page D 7 Comments Label Number Single Value plots only Scaled Unscaled Single Value plots only Yes No Single Value plots only Yes No Single Value plots only replace Jtem with entry from Fonts Item list pass valid font name Regular Italic Bold Bold Italic valid font metric RGB values separated by commas Comments Yes No Yes No Y T Linear Logarithmic Stationary Moving Sweep Yes No Y X Scatter channel number Y T Strip Chart Time Request only Mag F Phase F Frequency Request only contents of Location combo Yes No use string for time of day support use string for time of day support contents of Format combo fill out edit controls as passed for time of day supp
480. tLabel instrument Letter ChOffset ChanLabel instrument Letter ChOffset ChanType instrument Letter ChOffset ChanMinY instrument Letter ChOffset ChanMaxY Req XL CENE CAO RRR RRR Ux SS WER RRA RR Poke Format string string string single single integer string long int string sting integer integer long int string string string integer string string single single Page D 11 Comments CSV list of element letters used by DAT file date file was created time file was created sample rate of element letter frame duration in Clock Units number of channels in file CSV list of channels element letter and channel number frame duration in Number of Points X axis units Exponential Standard Binary or Fast Binary same as number of channels in file interleave of FFT data number of pre trigger points used when acquiring data factor and offset in mX b format lorO channel label yt time yfp frequency default channel minimum default channel maximum For all file info items except BufferLetters Letter must be replaced by the element letter of the buffer SM you are requesting For channel specific information ChOffset must be replaced by the 0 based sequential location of the channel from the Channels string For example if the Channels item returns A0 A5 A10 A15 and you are interested in the ConversionPoly for channel A10 the Item would be A 2 ConversionPoly c
481. ta When used with the Range function the average is calculated over the specified range only ravg argl Example RO ravg AO The Running Average function calculates the current arithmetic mean based on the current and all previous points in arg1 The output of the function has the same number of points per frame as argl Analysis and Frequency Analysis Page 12 17 Maximum Running Maximum Minimum Running Minimum Root Mean Square RMS Running Root Mean Square max arg1 Example SO max AO0 The Maximum function finds the value in arg1 that is closest to The output of the function is a single point which is produced after all points in arg are processed When used with the Block function one point is produced for each block of data rmax arg1 Example RO rmax A0 The Running Maximum function outputs the last point in argl that was closest to If the current point is the new maximum then the output of the function is equal to the current point otherwise the output of the function is the previous maximum The output of the function has the same number of points per frame as argl min argl Example SO min AO The Minimum function finds the value in arg that is closest to co The output of the function is a single point which is produced after all points in arg are processed When used with the Block function one point is produced for each block of data rmin argl Example RO rmin AO The
482. ta points stored in memory If this button does not appear the Standard method is used Standard Stores up to 32 768 points divided by the number of channels For example if four channels are acquired then 8 192 points per channel are stored in memory This is the simplest and safest of all the memory options If you are having any problems with the number of points available for Retrace set the Memory Allocation to Standard Complete Frame Stores the number of points specified in the of Points The advantage of this setting is it retains the maximum amount of data in memory but this is also the most memory intensive of all options This setting will produce more Out Of Memory errors in the Status Log than other methods Only use this setting if you are certain that there is enough memory for the data and have thoroughly tested the instrument running under normal operating conditions Pre Trigger Data Stores enough data points to satisfy the number of data points specified for the Pre Trigger length The same caveats described for the Complete Frame option apply For this selection the data available for the Retrace function is equal to the number of points specified for the pre trigger data regardless of where the trigger point is located For example if the frame length is 1 000 000 points and the Pre Trigger is 60 the Pre Trigger Memory option allocates 600 000 points When you acquire the data the trigger point occurs
483. tart your machine This command MUST be in the last line your AUTOEXEC BAT file Another option is to create a batch file that will run SMSTART Windows in Standard Mode and Snap Master The batch file might look like this cd sm smstart x c windows win s sm exe cd To allocate more memory for SMSTART you can include a number expressed in Kilobytes after the SMSTART command for example SMSTART 256 allocates 256 KB of memory By default SMSTART allocates 128 KB of memory For additional information about the SMSTART program type smstart All of Snap Master s features and capabilities are available when running under Windows 95 All comments about allocating buffers for data acquisition in the 386 Enhanced Mode section apply to Windows 95 as well Snap Master operates as a data display and analysis program when running under Windows NT The data acquisition features are not available When using any type of disk compression software such as DoubleSpace or Stacker the actual throughput rate for writing high speed data to disk in the Fast Binary format will decrease The actual performance for all data file formats will vary between computers As a rule of thumb avoid writing high speed data to compressed disks You should disable any disk caching software such as SMARTDRV if you are acquiring data using the Fast Binary format SMARTDRV is automatically installed with Windows 3 1 so you will have to remark this out of AUT
484. tch to Excel and highlight 10 cells Then select the Edit menu Paste Link command You will see that the item you see in the cell contents does not reference Snap Master at all In fact it shows the computer name and the name of the NetDDE link If all has gone well you should see either a or an actual data value If N A appears the link may not be correct In that case restart the tutorial When you return to the server and start the Snap Master instrument check back on the client machine You should see the data appear in the Excel cells in real time One way to test the throughput of your NetDDE connection is to include a Display element in the Snap Master instrument When you run the instrument there should be no delay between the time the Snap Master instrument stops plotting data and the Display window menu returns to its normal state If there is a delay try lowering the Sample Rate of the A D Demo or increasing the Block Size of the DDE Out This decreases the amount of DDE transfers occurring over the network Dynamic Data Exchange Page 6 21 6 7 Tutorial Sending Data To Snap Master Over NetDDE Note This tutorial requires two computers running Windows For Workgroups with sharing enabled on both computers Both machines need to be running Snap Master In this tutorial we will use the same instrument created in the previous sections for our data server Instead of using the Windows Clipbook as we did in the la
485. ted specifies the incremental range for each bin When selected specifies an absolute number of bins Specifies the range for the calculation Counting Histogram The traditional histogram counts the number of times data occurs within a certain Y axis range such as voltage Each Y axis range of input data is represented by a bin on the X axis of the output plot The Counting calculation counts the number of values exceeding the Threshold and plots the count on the Y axis as the output for each bin Settings Input Channel Calculation Output Bin Spacing Frequency Averaging Band Analysis Linear Band Analysis plots the average amplitude power or energy of a particular frequency range on the Y axis The amplitude power and energy values of the input data are calculated using the FFT Each frequency range is represented by a bin on the X axis in the output plot Settings Input Channel Calculation Output Bin Spacing Frequency Averaging Band Analysis 1 Octave 1 3 Octave etc Octave Band Analysis is like Band Analysis except the bins are divided into octaves instead of linearly Utility Elements Page 15 19 15 8 Tutorial Histogram Building the Instrument Performing A Histogram Calculation A D A A D Demo B Histegam C Display Figure 15 27 Instrument for Histogram Tutorial 1 Create a new instrument with the command in the Snap Master workspace button or select
486. ter Basics 2 3 Instruments Instrument Construction Guidelines Page 2 15 Changing An Existing View e Move the columns you do not want to see by selecting the items in the Visible Columns list and pressing the button to move them to the Hidden Columns e Change the order of the Visible Columns by selecting the items in the list and using the and buttons Deleting A View e Select the view from the View Name combo e Press the Delete View button to remove the view Now that you have been introduced to the basic concepts used in Snap Master it is time to present the guidelines and strategies for proper setup and use of your instruments These instructions will optimize the results of your instrument and your use of Snap Master When connecting elements together into an instrument it is important to follow the conventions given by Figure 2 11 This figure can be summarized as follows e Input Elements send data to Analysis and Output Elements e Analysis Elements send data to Output Elements An important item to remember is that data pipes send information through elements so that information can be received downstream using a minimum number of data pipes For example the instrument shown below shows data being sent from the A D Board to the Analysis element and through Analysis to the Display element As a result the Display element can show data from both the A D Board and the Analysis elements A D E 4 A D Demo
487. termination panel the five internal frequencies F1 through F5 and the Terminal Count T C from the previous counter counter 5 reads the T C from counter 4 counter 4 reads the T C from counter 3 and so on with counter wrapping around to read the T C from counter 5 For the T C from the previous counter and the fixed frequency inputs F1 through F5 you do not need to make a physical connection at the termination panel The Gate input controls when counting of the Source input occurs When the Gate condition is satisfied the counter proceeds as defined by the Source input Gating options include no gate counting proceeds unconditionally a High or Low state of the counter s Gate input a High to Low or Low To High transition of the counter s Gate input a High state of the previous or next counter s Gate input for example the Gate for counter 4 looks for a High state on the Gate input of counter 3 or counter 5 or a Terminal Count T C event on the previous counter For the T C from the previous counter or the Gate inputs of other counters you do not need to make a physical connection at the termination panel Counter Timer Load and Hold Registers Terminal Count T C Modes Mode A Mode B Mode C Mode D Mode E Mode F Page 9 15 The Output generates a digital High or Low based on the Terminal Count T C of the counter On a T C event of the counter the Output can produce a High Pulse where the Output changes
488. terrupt Input INT IN pin In addition the Interrupt Enable pin must be connected to Ground GND to activate the INT IN pin For many applications one of the counters on the hardware can be used as the master pacing clock Usually Counter 5 is used as the pacer in Snap Master In the 9513 Configuration dialog this channel is designated as an Internal Pacer You MUST physically connect the Output pin of the Internal Pacer counter to the Interrupt Input pin For example if Counter 5 is used as the pacer the following connections must be made the diagram assumes the pin outs of CTM 05 compatible Counter Timer hardware please refer to the hardware documentation for pin out information Counter 5 Output Digital Common Interrupt Enable Figure 9 1 CTM 05 Compatible Connections for Internal Pacer Using Counter 5 Page 9 2 9 1 Counter Timer Input Snap Master User s Manual The Counter Timer Input element has the same user interface as the A D and Digital In elements The main dialog used for the Counter Timer element is the 9513 Setup dialog which is opened from the Device menu Hardware Settings dialog 9513 Setup Configuration Connections 1 9513 Chip zi Source Souce1 z Prescaler Binary C BCD Count On Rising Edge C Falling Edge FOUT Enabled Gate HiEdge Gate 1 zi Source zl Output Always Lo E Source Divider Al Registers Counter
489. that seemed large for a single frequency becomes an excellent trade off when the frequency being measured does not coincide with the spectral resolution of the result Page 14 16 Blackman Snap Master User s Manual For the Triangular window we still see the large number of side lobes around 100 Hz but they diminish until almost gone around the 200 5 Hz signal This tells us that the Triangular window is actually better with frequencies that do not fall on spectral lines The width of the main lobe for the 200 5 Hz frequency is larger than the Blackman Harris especially at 60 dB but the response is better for the Triangular than for the Rectangular window Now we need to look at the case where the frequencies of interest are both on spectral lines but are relatively close together In Figure 14 7 a signal with a 100 Hz and a 103 Hz frequency component of equal magnitudes are measured Blackman Harris Triangular HO dB Rectangular 105 110 10 1 L 30 85 100 Frequency Hz Figure 14 7 Response of FFT Windows on Concentrated Frequencies Once again because the frequencies fall directly on the spectral lines the Rectangular window provides the closest response to the ideal Neither the Blackman Harris nor the Triangular window displays a sufficient signal drop in between the frequencies being measured For the Blackman Harris window this is because the main lobe width is always 7 spectral lines and there a
490. the A D Demo element Assume that the instrument name is TEST INS and the A D Demo is element letter A Number Snap Master TEST INS A SampleRate 100 String Snap Master lTEST INS A Units Secs Answer Snap Master l TEST INS A Continuous YES D 1 System Topic Item Exec R Poke Format Comments c Topics string Main open instrument list SysItems string DDE items for System topic Status string Ready Formats string supported DDE data formats Notes For commands to the Snap Master system the Topic is System and the Item is the request For example Snap Master l System l Topics DDE Commands and Parameters D 2 Workspace Topic Item Poke FileNew FileOpen filename FileSave FileSaveAs filename FileClose filename FileExit OptionsShowLog OptionsHideLog StatusLog Visible OptionsAutoArrange status OptionsToolbox status WindowCascade WindowTile WindowArrange HelpTutorial HelpAbout Hide Show DisplayConfirmDelete ConfirmSaveOnClose RRA KARA Path DefuserPath SysdataPath Version dllname Notes Replace filename with the full path and file name for the instrument Replace status with either On or Off D 3 Instrument Topic Item Poke instrument Start Stop ElementLetters ElementNames instrument instrument instrument ElementName ElementLetter Running instrument instrument Notes element letter A use Snap MasterlTEST INS ElementName A
491. the Counter 5 Output for the frequency measurement Pin numbers shown for CTM 05 compatible hardware Page 9 12 Running The Instrument Alternate Frequency Measurement Method Snap Master User s Manual Al vs Time Frame 0 Time Sec 20 A2 vs Time Frame 0 1000 0 Time Sec 20 Figure 9 10 Results of the Pulse Count Tutorial When you run the instrument you should see the number of counts increase as the frequency increases and vice versa As in the previous tutorial this signal is a TTL square wave which was varied from 900 to 4500 Hz There are at least two different ways to measure frequency with Counter Timer hardware in Snap Master This tutorial illustrates the simplest method which essentially measures the number of interrupts generated by the Internal Pacer between input signal edges The count is then scaled by the Sample Rate to define the frequency of the signal The drawback to this method is the relatively low resolution of the output Frequency resolution is a direct function of the sample rate because the counter is gated by the same signal that determines when to retrieve the value of the counter Low sample rates will have higher resolution than high sample rates because the counter is allowed to read more Source edges before the Gate resets the counter At 1000 samples per second the resolution is 1000 Hz which means you can only resolve in multiples of 1000 Hz 1000 Hz 2000 Hz
492. the Element menu Pipe Mode command 6 Save the instrument with the button or select the File menu Save Instrument As command Save the instrument as MULTFRME Summing Five 1 Open the A D Demo Settings dialog box Frames Into One Frame A D Settings Pacing Channel List Type Software P Location CIntemal Exieinal A2 Sample Rate 100 7 Sec Pacing Units Sec zl X Axis Label Time Triggers Free Running f pod e Input Ranges 10 to 10 Volts of Points 200 Demn Standard r Number of Frames Continuous Sine zi Stop After b frames Configuration r Status Messages oe cmn te Figure 15 35 A D Demo Settings 2 Set the Number of Frames to Stop After 5 frames 3 Select the OK button to close the A D Demo Settings 4 Open the MultiFrame Calculation dialog box Multiple Frame Calculation Input Channel Calculation Type Time Sum sd C Frequency C Average fames Output Rate Gaja E pe BET m C em ne Figure 15 36 MultiFrame Calculation Settings 5 Set the Channel to AO Because the A D Demo outputs time based data make sure the Time radio button is activated then select channel AO from the Channel list 6 Set the Calculation Type to Sum 5 frames Page 15 24 7 Set the Output Rate to Output Every 5 frames Snap Master User s Manual When you run the instrument with these settings you will
493. the File menu Close command For the second A D board we will use different settings for the sample rate frame length and channels acquired 10 Open the A D Settings for element B 1 Select a different Device than element A from the Device menu If you need to configure the second device select the Device menu Device Overview command 12 Press the button or select the Settings menu Frame Settings command Pacing Frame Length Type Hardware zl Duration 15 Sec Location Internal C External C of Points 750 Sample Rate 50 Sec Number of Frames Pacing Units Sec z C Continuous X Axis Label Time Stop After 1 frames CENE Figure 8 19 Frame Settings for Element B 13 Select the Hardware pacing type 14 Set the Sample Rate to 50 15 Change the Frame Length to a Duration of 15 seconds 16 Change the Number of Frames to Stop After 1 frame 17 Press the OK button to close the Frame Settings 18 Make sure the first channel or the channel you have your input wired to has a Yes in the Active column 19 Close the A D Settings window with the File menu Close command 20 Save the instrument with the button or select the File menu Save Instrument command Page 8 20 Snap Master User s Manual Saving Data From 1 Open the Disk Out Settings by double clicking on the Disk Out element Only One Channel Disk Out Settings File Na
494. the Logical item in the Category list then double click on the Find Time of Event item in the Function list to open the Function Builder Find Time of Event Calculation find A0 lt 0 ch Fa Quick Functions Ana or xor uo Options lt Default Points gt Points Time Syntax find argumentl Description Returns the frame time of the first point in argument which is True equal to or greater than 1 Argument usually contains a comparison i e A055 Cancel Help Figure 12 22 Function Builder for Find Time of Event Now that we have the Find Function Builder open we need to define the condition to look for using the Comparison Function Builder 10 Press the button to open the Comparison Function Builder Page 12 36 Running The Instrument Snap Master User s Manual Comparison Comparison eo Ch Fi zl 0 Options lt Default Oversample gt Oversample Undersample Syntax argument Comparison argument2 Description Compares each point of argument and argument2 When the comparison is true the function produces a value of 1 When the comparison is false the function produces a value of 0 Le Cancel Help ep Figure 12 23 Function Builder for Comparison 11 Press the button in the first argument and click on channel AO 12 Select the lt item from the combo box 13 Enter 0 in the second argument edit control 14 Press the OK button to close the Comparison
495. the MultiFrame Calculation dialog and change the value to 1 When you run the instrument this time the output channel BO looks different for each frame For frame 1 BO looks the same as AO For frame 2 BO is the sum of the first two frames of AO Frame 3 of BO is the sum of the first three frames of AO and so on until the final frame which looks the same as in the previous section If you wish to experiment further try changing the number of frames in the A D Demo to Stop After 10 The output of BO will look the same as above for the first five frames On frame 6 BO starts over and is equal to frame 6 of AO Frame 7 of BO equals the sum of frames 6 and 7 of AO etc IndustrialSQL Page 16 1 Chapter 16 IndustrialSQL 16 1 Connecting to the Server eee eee e ee eese eres esee eene eese en eese tena asset tasses esses etes asset enses ss etes estes esee tense asso sosisini 16 1 16 2 IndustrialSQL In Settings RRR 16 2 16 3 Tutorial Using The IndustrialSQL In Element ssccssssssssssssecsssecsssesscssssssssenssessesscssssssnsssssessessssssssesssseees 16 4 The IndustrialSQL In element makes Snap Master a client application that allows you to query tags from the IndustrialSQL Server database and use them as Snap Master channels Once you have added tags to Snap Master you can analyze and plot the data using other Snap Master elements Before using this element you must install
496. the Standard Binary files is the Fast Binary does not convert the acquired data into the floating point number before it is written to disk This saves time during the write cycle and allows for a higher throughput rate In addition all of the input channels are written to the disk file in order to maximize the performance While the instrument is writing data using the Fast Binary format data can not be viewed using the Display element This is because displaying data on the screen requires numerous calculations which in turn reduces the speed of writing the data directly to disk Therefore if you attempt to start an instrument with an element that does not support the Fast Binary data format a message will appear on screen informing you that the instrument can not run in its current configuration NOTE If you are using the Fast Binary data format DO NOT use any disk caching software such as SMARTDRYV which comes with Windows Disk caching software will degrade the performance of the Fast Binary format and your actual throughput rates will be lower than without the cache In addition to the native file formats Snap Master can also read and write data in generic formats that can be used by other programs These formats include Format Data Frame Display While Speed Frequency Type Based Storing Data Binary Plotter Yes Med Yes ASCII Plotter ASCII Yes Low Yes Comma Separated CSV ASCII No Yes Low Yes Variable Disk I O D
497. the array by the number of points specified by points A positive value for points shifts the data forward in time or frequency for the Frequency Analysis element and a negative value for points shifts the data backward in time or frequency For example use a time shift of 1 to use the previous value of arg1 Any missing data points at the beginning or end of the frame are zero filled range start_at stop_at arg1 Delimiters start_at Starting position of the range function stop_at Ending position of the range function Options p Frame Point Number t Frame Time Analysis or Frequency Frequency Anaysis Examples RO range 1 100 A0 RO range t 1 10 A0 The Range function performs the contents of arg only between the points specified by start at and stop at This makes it possible to perform a calculation over a subset of the channel data To accomplish this the Range function sets all data points outside of the range to 0 Make sure that the stop at point is after the start at point In addition the start at point must be greater than 0 and the stop at point must be less than the total number of points in the frame Analysis and Frequency Analysis Page 12 23 Block If you want to integrate channel AO from point 100 to point 200 the range function belongs with channel AO In this case the equation reads RO intg range 100 200 A0 This equation zeroes out channel AO outside of the range then performs the integrat
498. the equation in another equation which is often used to define constants for example 9 references the constant in row 9 of the table Using the Enhanced Syntax this column specifies if the equation in the row is active the Run cell is blank or inactive indicated by a X in the cell so the equation is ignored Using the Original Syntax the active equation is indicated by a in the Run cell Cell where each equation is described Each comment can be up to approximately 250 characters long Cell where the actual equation or equation macro using the Original Syntax is defined Each equation can be up to approximately 250 characters long Allows the user to define a channel label for all result channels defined in the Equation Definition If the equation line contains an equation macro using the Original Syntax then the label is assigned to all result channels defined in this line Allows the user to define the units for all result channels defined in the Equation Definition If the equation line contains an equation macro using the Original Syntax then the units are assigned to all result channels defined in this line Analysis and Frequency Analysis Quick Function Reference Please refer to section 12 2 for more information on the individual functions Addition Subtraction Multiplication Division Power Absolute Square Root Exponential Log Base 10 Natural Log Cosine Sine Tangent ArcCosine ArcSine ArcTan
499. the instrument In addition the Instrument Response defines how Snap Master requests and interprets the incoming data The strings defined in this dialog are stored in the Snap Master instrument file This way when you open this instrument at a later date the original string set is preserved In addition you can save the contents of the table in a separate file similar to saving a Display settings or a Sensor assignments file Page 10 4 Snap Master User s Manual String Table Parameter Files The New Open and Save buttons above the string table enable the user to store and recall the contents of the String Assignments dialog These string files are saved using a 232 extension for example TEST 232 The actual files are saved in a binary format so you cannot edit them with a text editor String Table The string table specifies the actual command strings sent by Snap Master over the serial port to the external equipment Up to twelve separate strings can be saved in the table For each command you specify the command Type if it is used in this instrument and the ASCII String sequence accepted by the external equipment Type Use The Initialization command sends the string once at the start of a frame which is often used to configure the external equipment before data collection begins This command requires a response to come back from the RS 232 device Minimally this response string must contain a terminator
500. the sampling frequency These are used for converting analog continuous data to digital discrete data using an A D converter The inputs to the filters are the signals from the physical sources and the output of the filter is then sent to the data acquisition board However the anti aliasing filter may not be able to completely eliminate aliasing because analog filters cannot have a completely ideal vertical roll off There is a characteristic transition range and data above their cut off frequency is attenuated but not eliminated The cutoff frequency of a filter is the frequency where the signal is attenuated by 3 dB about 30 A good procedure for specifying the characteristics of an anti aliasing filter is to consider 1 the desired highest frequency of unattenuated data 2 the maximum tolerable contamination by aliased frequencies and 3 the phase distortion in the frequency range of interest caused by the analog anti aliasing filter e Depending on the shape of the filter characteristic curve in the transition region where the filter is changing from a flat characteristic to its terminal slope the cutoff frequency may have to be set much higher than the highest data frequency of interest A very sharp cutoff filter will not require as much difference as a soft transition filter e Aliasing is effectively a folding back of data above half the sampling rate and mixing it with data below that frequency often called the N
501. the selected Color and you can set multiple colors simultaneously by selecting more than one channel from the list Bar Meter Picture Settings r Picture Fill Direction Style t m M Vertical re Horizontal Axis Settings Define Fill Regions Fill Regions 1 Beset Fill Regions Cancel Help Figure 3 11 Bar Meter Picture Settings One unique feature of bar meters is the ability to use a picture to define how the bar meter appears on screen The Bar Meter Picture Settings dialog box lets you change the appearance of the bar meters by including either a default or a custom picture The Picture Style lists the default pictures available in Snap Master as well as the None which uses just a normal rectangular bar and User Defined options When including a User Defined picture in the bar meter you must define the Fill Regions for the picture This is where Snap Master actually draws the bar graph in The region can be any shape as long as there is a complete outline of black to define the boundaries For example the pictures shown in 3 12 illustrate the correct way to create a proper fill boundary The picture on the left contains a solid boundary while the picture on the left has an open space where the boundary of black is broken Page 3 14 Dial Meters Dial Meter Settings Snap Master User s Manual C Correct Fill Incorrect Fill Boundary Boundary No Full Blac
502. the two cursors For markers and absolute cursors the value is 0 Pg The Display Page of the plot associated with the cursor or marker Plot Title The title of the plot associated with the cursor or marker Show Specifies if the cursor or marker is visible in the plot The available options are Yes and No You can poke these values to the Cursor Data table using DDE Marker The number of the cursor or marker This number is referenced in the DDE Link Refer to Appendix D for more information Auto Retrace Auto Layout Display Settings Turn the Auto Retrace function on or off Each time the Display window is refreshed the current Retrace Mode Buffer Retrace or Full Retrace is used to redraw the data Automatically arrange the Display plots according to the Auto Layout settings in the Display Defaults dialog box Display Defaults Auto Layout Options 1 Iv Gn Iv Command Bar One Channel Per Plot C Overplot Same Element Letter T Scroll Bar C Overplot Same Channel Number M Auto Retrace C Overplot Channels With Same Units I Apply Defaults For New Plots Overplot l Use Multiple Y Axis r z I Warn If Different Units Max i Channels T Delete All Plots Before Auto Layout Plot Technique T Confirm Delete Before Auto Layout C All Points Automatic IV Status Bar Retrace Mode Buffer Retrace C Full Retrace Cursors Select All Secondary Channels OK Cancel Help Figure 3 18 Display Defaul
503. there is to it Using a few simple steps you can display data from any element that outputs data Of course it is possible to configure the elements to perform more specific tasks but even that is not difficult Throughout the manual we will illustrate features with specific tutorials When you are done looking at the data press the button or the Stop menu command 2 5 A D Demo Element A D A D Demo Settings Pacing The A D Demo element mimics the operation of A D I O hardware in Snap Master by generating arbitrary waveforms according to the parameters given in the A D Settings dialog The A D Demo element is used for most of the tutorials in this manual regardless of which modules you have installed A D Settings pPacinn O Channel List gt Type Software al AO Al Location C Internal C External re Sample Rate 100 Sec Pacing Units Sec zl X Axis Label Time Triggers Free Running Frame Length Input Ranges 10 to 10 Volts C Duration B Soo tt of Points 200 m Memory standard Device r Number of Frames ru Sine zl C Stop After 1 frames Enron Status Messages cae ueo Figure 2 17 A D Demo Settings The Pacing parameters define the sampling rate of the A D Demo element The units are normally defined in seconds as indicated by the Units field with the X Axis Label defined as Time The number in the Samp
504. tial value of the counter Counting is enabled on a Gate edge When the counter reaches T C the counter value is reset to the Load register value Counting does not begin until a new Gate edge condition is satisfied This differs from Mode C which can only be triggered once per frame Page 9 16 Mode G Mode H Mode Mode J Mode K Mode L Mode N Snap Master User s Manual Software Triggered Delayed Pulse One Shot Output Onl At the beginning of each frame the Load register sets the initial value of the counter then begins counting When the counter reaches T C the counter value is reset to the Hold register value and the count restarts from the new value When the counter reaches the second T C the counter reloads the Load register value and disarms itself until it is rearmed with a new frame A software triggered delayed pulse one shot is obtained by setting the Output to the T C Toggled signal The Load register value determines the delay between when the counter is armed and the output pulse starts The Hold register value determines the duration of the pulse Software Triggered Delayed Pulse One Shot with Hardware Gating Output Onl This mode performs the same function as Mode G except that the count only occurs when the Gate condition is satisfied This allows the Gate input to extend both the initial output delay and the pulse width Hardware Triggered Delayed Pulse Strobe Output Only This mode performs the s
505. ticalPosition instrument Marker Fill instrument Marker Color instrument Marker Shape instrument Marker Height instrument Marker Width Req KS RR Ry RS LOK RAR Poke Ee S eS BOX SCRI Format string string integer string string string string string string string string string string integer integer Comments Yes No Ves No also for markers contents of Background combo replace Jtem with entry from Fonts Item list pass valid font name Regular Italic Bold Bold Italic valid font metric Left Center Right Top Center Bottom contents of Fill combo RGB values separated by commas Rectangle Ellipse Page D 10 Cursor Table Topic instrument instrument instrument instrument instrument instrument instrument instrument instrument instrument instrument Item Exec Cursor Ch Cursor PtH Cursor XValue Cursor XUnits Cursor Y Value Cursor Y Units Cursor Type Cursor Slope Cursor Pg Cursor Title Cursor Show D 6 Disk In Topic instrument instrument instrument instrument instrument instrument instrument instrument instrument Item Exec R c FileName FileComments AllFrames StartAtFrame StopAtFrame Continuous PauseAfter Paced PlaybackSpeed RRR RRR ASCII Import Topic instrument instrument instrument instrument instrument ins
506. tics for the function result are determined by the Options We recommend that the Oversampling option is always used for the Default Option for this function arg arg2 E Options E Examples Oversampling Undersampling R0 A0 AI1 R0 A0 o Al The Division function divides the current point in arg by the current point in arg2 The frame characteristics for the function result are determined by the Options We recommend that the Oversampling option is always used for the Default Option for this function arg arg2 E Options E Examples Oversampling Undersampling R0 A0 AI R0 A0 fo Al The Power function raises the current point in arg to the current point in arg2 The frame characteristics for the function result are determined by the Options We recommend that the Oversampling option is always used for the Default Option for this function Analysis and Frequency Analysis Page 12 13 Absolute Square Root Exponential Natural Antilog Base e Logarithm Base 10 Natural Log Base e abs arg1 Example RO abs AO If the current point in arg is a negative value the Absolute function converts it to a positive value Positive values remain unchanged sqrt argl Example RO sqrt A0 The Square Root function takes the square root of the current point in argl exp arg1 Example RO exp AO The Exponential function raises the current point in arg to the value e log argl E
507. to Retrace selected or press the Retrace button in the command bar If the plot you zoom in on belongs to a linked zoom group which is set in the Layout all plots in that group will zoom in to the same X and Y axis range X And Y Axis Changes the ranges on both the X axis and the Y axis Pressing the button in the command bar zooms in both the X and Y axes X Axis Changes the range on the X axis only The Y axis range remains constant Y Axis Changes the range on the Y axis only The X axis range remains constant Lets you restore the axis ranges to a previous setting After you select a Zoom Out mode the mouse pointer changes to Select the plot you want to zoom out by positioning the mouse pointer over the Display region and pressing the right mouse button Snap Master remembers the last five zoom levels so you can move between resolutions to see your data more clearly If the plot you zoom out on belongs to a linked zoom group which is set in the Layout all plots in that group will zoom out to the same X and Y axis range Previous Restore the X axis and Y axis ranges to the values used before the previous Zoom In command Pressing the button in the command bar zooms out to the Previous range Original Restore the X axis and Y axis ranges to the values used when the instrument was last started Display Zoom Auto Scale Retrace Now Cursor Data Page 3 19 The Auto Rescale function is a special t
508. to the specified Display page Redraws the data in the plots Zoom in both X and Y axes Zoom out to previous level Automatically rescale the Y axis Place a new data cursor Place a new data marker Place a new text annotation Show or hide the Cursor Data table I Es S EE I I9 Er Print the current Display Page to the default printer Scroll Bar The Scroll Bar is used to pan through selected plots For example if you have a 10 second frame and the plot shows from 0 to 1 seconds you can use the scroll bar to view 1 to 2 seconds 3 to 4 seconds etc To select the plots controlled with the Scroll Bar highlight them by holding the CTRL key and clicking the mouse on the plots then use the Scroll Bar to move around in the frame Display 3 2 Plot Types Default Plot Templates Y vs T Plots Page 3 3 Snap Master s plot types can be broken down into related categories with subtle differences between each different plot type Use these categories to decide what type of plot to use Category Plot Type Special Features Time Domain Y vs T Log Plots Sweep Graphs Strip Chart Simulates moving paper Frequency Domain Mag vs F Plot Magnitude vs Frequency Phase vs F Plot Phase vs Frequency Channel vs Channel Y vs X Use channel data as X axis Scatter Points not connected by line Single Value Digital Meter Visual alarms display value Indicator Visual alarms Bar Meter Include custom pictures Dial Meter S
509. tring string Snap Master User s Manual Comments Yes No lowest available channel number highest available channel number space delimited list of active channels for example 0 1 2 4 Internal External lowest active channel number highest active channel number opens Configuration dialog 1 to8 One Per Channel or None One Per Channel or None Comma separated list of all available programmable ranges for the channel Use for software programmable gain hardware Comma separated list of all available programmable ranges for the channel Use for jumper programmed gain hardware valid range string Yes if channel is active use just number portion DDE Commands and Parameters Page D 15 Counter Timer Settings Topic Item Exec _ Rec Poke _ Format Comments instrument ChipNum Prescaler string Binary BCD instrument ChipNum FoutEnabled string Yes No instrument ChipNum FoutSource string T C n 1 Src1 Src2 Src3 Src4 Src5 Gatel Gate2 Gate3 Gate4 Gate5 F1 F2 F3 F4 ES instrument ChipNum FoutDivider integer 1tol6 instrument ChipNum CounterNum Function string Internal Pacer Mode Custom Pacer Frequency One Shot Pulse Count Pulse Width Rate Gen Rate Gen Gated instrument ChipNum CounterNum Source string T C n 1 Src1 Src2 Src3 Sre4 Src5 Gatel Gate2 Gate3 Gate4 Gate5 FI F2
510. trolled by the Symbol Settings group The Appearance setting specifies how the marker looks either as an Outline where the symbol is only outlined Solid where the symbol is filled in or None the symbol does not appear The Shape is either a Rectangle or an Ellipse and uses the Height and Width which are measured in screen pixels to determine the size of the symbol The Symbol Color button opens the Windows standard Color dialog and allows you to set the color of the symbol The label for the marker is specified in the Label field This can also be changed from the Cursor Data table The Appearance settings for the label are Opaque the grid lines and waveforms underneath the label are covered Transparent the grid lines and waveforms underneath the label are shown and None the label is not shown The Position buttons specify where the label appears in relation to the symbol The Label Font button opens the Windows standard Font dialog box which sets the font and size of the label text The label text color is set to the Window Text color specified in the Windows Control Panel Display New Text Page 3 27 Text annotations allow you to include additional text information directly in the Display ext window When placing a text annotation the mouse pointer changes to T Text annotations are similar to markers except that there is no associated data point and the text can be placed anywhere within a plot window which will accep
511. trument instrument instrument instrument Item Exec R c Rate Duration Points MinY MaxY FrameLengthType LinesToSkip UseLabels AutoDetectPts ARS S IN Poke X RAR RC UA y e x e NONO NONUNCNON Format string long int single string single string string single integer string string Format string string string long int long int string long int string integer Format single single long int single single string integer string string Snap Master User s Manual Comments Abs Rel Marker valid only for Rel cursor Yes No Comments full path and file name Yes No Yes No Yes No speed multiple between 10 slowest and 10 fastest with 0 equaling normal speed Comments Duration Points Yes No Yes No DDE Commands and Parameters File Info Topic Item Exec instrument BufferLetters instrument Letter Date instrument Letter Time instrument Letter ActFreq instrument Letter ActSweep instrument Letter NumChans instrument Letter Channels instrument Letter NumPoints instrument Letter ClockUnits instrument Letter FileType instrument Letter Interleave instrument Letter FFTBlockSize instrument Letter PreTriggerPts instrument Letter DataInfo instrument Letter ChOffset ConversionPoly instrument Letter ChOffset ChanUnits instrument Letter ChOffset Defaul
512. ts The Display Defaults are used each time you include a new Display element in an instrument These settings do not prohibit you from changing these settings in each plot they only provide you with a customized starting point Display Status Bar Settings Auto Layout On One Channel Per Plot Overplot Same Element Letter Overplot Same Channel Number Overplot Channels With Same Units Use Multiple Y Axes Warn If Different Units Max Channels Delete All Plots Before Auto Layout Confirm Delete Before Auto Layout Cursors Select All Secondary Channels Options Command Bar Status Bar Scroll Bar Auto Retrace Apply Defaults For New Plots Retrace Mode Page 3 21 Auto Layout function is enabled Create a separate plot for each channel Overplot channels from the same element letter Overplots channels from different element letters with the same channel number Overplots channels with the same units When overplotting create a separate Y axis for each channel When using the Overplot Same Element Letter and Overplot Same Channel Number modes you are informed that channels with different units are being plotted on a single set of axes Sets the maximum number of channels assigned to a single plot Clears the contents of the Display Settings table before performing the Auto Layout Asks you if you want to delete all existing plots before performing the Auto Layout When selected each new cu
513. ts for force such as in Ib The Dynamic Flexibility function is equivalent to Compliance and is the inverse of Dynamic Stiffness FFT Mobility Dynamic Accelerance Dynamic Stiffness Transmissibility Dynamic Inertia Page 14 11 Mobility is a special transfer function used in mechanical systems In order to use this function the two input channels must have the same frame characteristics The numerator Ch1 of the calculation is a signal measuring velocity and the denominator Ch2 is a signal measuring force The result units are units for velocity over the units for force such as in sec Ib The Mobility function is the inverse of Impedance Generally Mobility is used for series combinations of interconnected mechanical elements Dynamic Accelerance is a special transfer function used in mechanical systems In order to use this function the two input channels must have the same frame characteristics The numerator Ch1 of the calculation is a signal measuring acceleration and the denominator Ch2 is a signal measuring force The result units are units for acceleration over the units for force such as n secY Ib Dynamic Accelerance is the inverse of Dynamic Inertia Dynamic Stiffness is a special transfer function used in mechanical systems In order to use this function the two input channels must have the same frame characteristics The numerator Chl of the calculation is a signal measuring force and the denominator
514. tter have the same number of points per data frame Transfers the acquisition or calculation rate of the channel Each channel in Snap Master has an associated rate used for processing purposes For example the rate for channels originating from an A D Board is equal to the sample rate of the board For the Analysis element the rate value is equal to the number of points divided by the duration Transfers the current frame number of the channel Transfers the label of the Y axis associated with the channel Custom labels are assigned to a channel with either the Sensor element or the Analysis element Otherwise the element letter and channel number are used as the yLabel Transfers the units of the Y axis associated with the channel Custom units are assigned to a channel with either the Sensor element or the Analysis element Otherwise the default units of Volts are used for the yUnits Transfers the factor value of the channel if the Sensor element has assigned a sensor to an incoming channel If the Disk In element is replaying a file that was scaled with the Sensor element the factor is still available from the data file Transfers the offset value of the channel if the Sensor element has assigned a sensor to an incoming channel If the Disk In element is replaying a file that was scaled with the Sensor element the offset is still available from the data file Transfers the default minimum value for the channel This is not
515. ttings Window Width 200 2 points Start At Point Overlap points Spectral Resolution 0 2500 Hz T Include DC Component Type Parabolic z paren T Average Spectra Across 0 frames Rectangular Riemann X Partial Frame C Zero Extend Ignore Description Specifies the result channel for the calculation lt lt Previous Line Cancel Help Next Line gt gt Figure 14 20 FFT Equation Builder Settings for Cross Power Spectrum 4 In the Result Channel text box type MO 5 Select Cross Power Spectrum from the Function list 6 Select channel AO from the Ch 1 list 7 Select channel DO from the Ch 2 list 8 Set the Window Width to 200 9 Press the OK button to close the FFT Equation Builder 10 Close the FFT equation table using the File menu Close Equations command 11 Save the instrument with the button or with the File menu Save command E Display Page 2 Beles Eile Edit View Settings Start Layout Cursor Help o seis E 2 A Volts 2 Time Sec a 25 E Ss a a 5 0 o Frequency Hz Figure 14 21 Results of Cross Power Spectrum When you start the instrument the data for channels AO and DO appear on screen in real time When the end of the 200 point window width is reached the cross power spectrum is displayed in the appropriate plot as MO Figure 14 21 shows a
516. ttings dialog box 7 Save the instrument with the button or select the File menu Save Instrument command Running The 1 Press the button or the Start menu command Instrument If your hardware is configured correctly then the data should appear on screen and the data written to disk If the Status Log appears with an ERROR entry follow the remedy listed If all else fails verify the hardware Configuration and your A D Settings Data Acquisition Page 8 21 8 7 Tutorial Acquiring Digital Data Building the Instrument Configuring the Digital In Element Acquiring data with the Digital In element uses the same steps as acquiring using an A D element Let s review the steps again this time using a Digital In element DIG IN A Digital In B Display Figure 8 22 Instrument for Digital Acquisition Tutorial 1 Create a new instrument with the button or select the File menu New Instrument command in the Snap Master workspace 2 Place a Digital In element and a Display element in the instrument 3 Activate Pipe Mode with the button or select the Element menu Pipe Mode command 4 Connect the Digital In element to the Display element 5 Turn off Pipe Mode with the button or select the Element menu Pipe Mode command 6 Save the instrument with the button or select the File menu Save Instrument As command Save the instrument as DIGIN 1 Open the Digital In by double clicking on the element A Dev
517. tude and phase of the output signal The results are then presented with respect to frequency The Inverse FFT converts frequency domain data to the time domain The inverse of the FFT is the equivalent of an all pass filter Due to the nature of the FFT and the windowing technique the inverse FFT may not be the exact time domain function that generated the FFT in the first place If a window type other than Rectangular is used the result of the Inverse FFT is the original waveform modulated by the scaling window The Auto Power Spectrum function calculates the average power in each frequency band of a single channel Ch1 from the instantaneous amplitude spectrum output by the FFT algorithm Ch2 is not used for this function The result units are the square of the input units such as volts i2 or psi The Auto Power Spectrum differs from the Auto Power Spectral Density which is normalized based on the bandwidth of the window type The Auto Power Spectrum function should be used with signals that have little or no noise and are coherent signals to avoid any effects from the normalization procedure Note that the Auto Power Spectrum in the frequency domain is equivalent to a Circular Auto Correlation However the correlation function in the Analysis element is a zero padded linear correlation Therefore the inverse FFT of the power spectrum of a signal will not equal the auto correlation of that signal as calculated by the Analysis element
518. two rows instead of one Display Layout Ej 8 E 4 amp Insert Delete Plot Settings Channel Settings Page Settings Figure 3 36 Display Layout Using Multiple Pages 1 Select the Layout menu command 2 Position the selection box in the third row Page column 3 Change the page to 2 Again we use the drop down list to select a Display page There are 8 possible pages to choose from and an N option The N page is a null page where a plot is moved if you do not want to delete it in case you have customized many of the settings and you do not want to plot it Each Display Page can have its own title which is shown in the title bar of the window Let s change the title for Page 2 1 Press the Page Settings button Display Page Settings 2 Page Default Title Auto Rows Auto Cols Title iDispl Yes Figure 3 37 Display Page Settings 2 Position the selection box in the second row Title column Display Changing The Display Page Rows and Columns Running the Instrument Page 3 37 3 Type Custom Y vs X Plot then press ENTER Notice that when you press ENTER with your new title the Default Title column changes to No This means that you are using your custom title To change back to the default title for the page move to the Default Title column and select Yes from the list Another item
519. u attempt to start Windows in Standard Mode you will receive an error message The major differences between the two modes are how DOS sessions are handled and virtual memory In 386 Enhanced Mode you can have multiple DOS sessions running concurrently while Standard Mode only allows one DOS session at a time Also 386 Enhanced Mode allows you to use part of the hard drive to emulate RAM using virtual memory Because 386 Enhanced Mode allows for multiple Virtual DOS Machines certain tasks operate more slowly than in Standard Mode In Snap Master this will usually be most evident while performing high speed data acquisition If you encounter frequent overruns while acquiring data try switching to Standard Mode using the s command line switch when starting Windows When you are using the Data Acquisition Module to acquire data you must allocate memory for any I O hardware which uses DMA Direct Memory Access to transfer data from the hardware to the computer For hardware that does not use DMA you do not need to allocate any special buffers In general any I O hardware that uses DMA requires a 64 KB kilobyte block of memory to write into Therefore for each I O hardware function that uses DMA you need 64 KB of memory in the buffer If you encounter messages in the Status Log telling you that no buffer could be allocated you must either increase the size of the buffer or close other instruments in the workspace that contain DMA hardw
520. u to enter new channel numbers or constant values using your mouse To open the On Screen Keypad click on an edit control using the right mouse button To define a channel select the Channel radio button the element letter of the new channel then use the on screen keypad to enter the channel number To enter a value only select the Value radio button and use the On Screen Keypad to enter the value Analysis and Frequency Analysis Page 12 7 Function Builders Settings Menu Analysis Settings Integration Calculation intg rangelfind R2 2 3 find R2 6 9 I A0 Quick Functions m Options lt Default Rectangular gt Rectangular Simpson s Rule Syntax inta argument Description Calculates the area under the curve of argument with respect to time OK Cancel Help Figure 12 5 Function Builder for Integration When you double click on a function in the Function list a special dialog called a Function Builder opens Each Function Builder is designed to guide you through the required function arguments and optional parameters for the function The complete syntax for the function along with a description for the active control is displayed at the bottom of each Function Builder The required number of arguments for the function is indicated at the top of the dialog by the number of available edit controls Any applicable Quick Function buttons are shown along with a list of Options for the function For exampl
521. ual for the best results More information about the window width is provided in a later section Waveforms can be classified as either continuous or transient and continuous waveforms can be further broken down as either periodic or non periodic Periodic waveforms have an integral number of complete cycles and the start and end points are equal A waveform is non periodic if it does not contain an integral number of cycles or does not have the same start and end points A transient waveform consists of a single event followed by in some cases also preceded by a steady state value The DFT algorithm assumes that the waveform being analyzed is periodic and is infinitely long One of the fall outs of this assumption is that the value of the first point in the window is equal to the value of the last point in the window However in most cases the waveform is non periodic and even transient so the start and end points do not match To trick the DFT algorithm into believing that this window of data is periodic we can match the end points using a window type other than Rectangular which actually performs no scaling at all Many window scaling functions multiply the start and end points by zero to make the waveform appear periodic This is especially useful for waveforms which consist of a large number of frequencies in which case it is difficult to acquire an integer number of cycles To see the effect of a specific window type on the end points
522. ual for your specific equipment for the correct string sequences The String contents may contain any ASCII character along with special C like escape sequences for specific characters as listed below Null Table 10 1 RS 232 Escape Sequences Null Instrument Response The Instrument Response group defines how Snap Master requests and interprets the incoming data from the external equipment These settings are used by the Query command in the string table Snap Master assumes that the ASCII string or data packet returned over the serial port contains up to 32 pieces of information called tokens each separated by a delimiter A special termination character is used to indicate the completion of the string In general the string would look like this for one channel token termination Or it would look like this for multiple channels token delimiter token2 delimiter token25 termination The overall format of this string returned over the serial port is described in the Format text box Each token is separated by a space in the Format description without including the Delimiter or the Termination characters The Format description should look like this token token2 token3 token24 token25 There are three types of information contained in a token a Literal Match a Place Holder and Channel Data Both the Literal Match and Place Holder tokens may contain any ASCII character or character sequence but Channel Data toke
523. ual sign We recommend using the Enhanced Syntax for all new Snap Master instruments because you will then be able to access all of the built in functions using the Enhanced Syntax The Original Syntax and its options are provided for backwards compatibility with files created by Snap Calc and Snap Master version 2 x and earlier Page 12 8 Snap Master User s Manual Analysis Table Format The Analysis Table Format group specifies how the equation table operates The Run All Equations option uses all active equations in the equation table for its results processing Active equations are indicated by a blank cell in the Run column so rows with an X in the Run column are not processed When the One Active Equation option is selected only one equation line can be active at a time so equation macros are used to process multiple equations used with previous versions of Snap Master The Show Comments Column check box determines if the Comments column is visible in the Equation Table When using the Run All Equations option you may want to hide the Comments column to increase your screen real estate by writing comments in line with the equations and turning on the X in Run column Memory Optimization The Result Data scroll bar lets you set the number of points per channel that are stored in memory by the Analysis element This setting affects all functions but has a more dramatic impact on the Time Shift Range especially when using the F
524. ue as the right variable gt Greater Than The left variable has a larger value than the right variable lt Less Than The left variable has a lesser value than the right variable gt Greater Than Or Equals The left variable has a value that is either larger than or the same as the right variable lt Less Than Or Equals The left variable has a value that is either lesser than or the same as the right variable lt gt Not Equal To The left variable has a different value than the right variable The following table describes the valid comparison types allowed by the Command element Note that the comparison of a Constant to a Constant is a method used to define an IF statement result as always True or always False Variable 1 Variable 2 Example Channel Channel C1 gt C3 Channel Constant AO lt 5 Constant Constant 3 3 State Variable Constant Valvel lt gt 5 State Variable State Variable Valvel lt Valve2 Page 13 6 Snap Master User s Manual Logical Functions By combining a series of comparisons together with the AND OR and XOR logical operators you can create a complex statement without using multiple layers of IF statements In addition the NOT operator can be used to make the statement true when the condition is false AND argl and arg2 Example If A0240 and A1 gt 50 Then D3 1 End If The AND function compares the current point in arg with the current point in arg2 producing the following r
525. uency Specifies the units used to define the sample rate For the Analysis element the default units are seconds For the Frequency Analysis element the default units are Hz How Frame Characteristics Are Determined Each element letter contains information about the number of points per frame and the duration of the frame which are collectively called the frame characteristics of the element For the Analysis element the frame characteristics consist of the sample rate which is equal to the points per frame divided by the frame duration in seconds For the Frequency Analysis element the frame characteristics are made up from the frequency resolution the maximum frequency and the number of points or spectral lines When you create a new result element letter Snap Master uses the contents of the first equation to use the element letter to determine its frame characteristics There are two main factors which affect the resulting frame characteristics e The output size array single point of the first function called in the equation e The frame characteristics of the input to the first function called in the equation e Ifthe frame characteristics cannot be determined for the Analysis element a sample rate or frequency resolution of 1 Hz and a frame length of 1 point is assigned Page 12 10 Snap Master User s Manual A D 4 4 D Demo B Analysis C Display D A D Demo Figure 12 8 Example Instrument for Deter
526. ul you will return to the IndustrialSQL In Settings dialog and the Database Connect button will appear pressed in You must be connected to the database before continuing the tutorial IndustrialSQL In Settings Star Time 11 13 1997 10 00 00 zl End Time 11 13 1937 10 05 00 v Resolution 1000 Elf Public Groups H E All String Tags H A All Event Tags H Private Groups X All Analog Tags m All Discrete Tags H E InTouch Nodes m System Status Tags nj EA SysActivellsers EA SysCritEnCnt EA SysDateD ay E SysDateMonth EA SysDateYear EA SysEnEnCnt imi E SysEnoRate E SysFatalE Cnt EA SyslODriverBytes E SyslODriverCPS 2 SysMinutesRun E SysSpacedlt z ms All Groups All Analog Tags Active Tags Np oe Re Fe a 75 H Q System Objects E rm SysMinutesRun JA zi Remove Current Tag Remove All Tags Cancel Hep Figure 16 6 IndustrialSQL In Settings E Display Page 1 3 Press OK to close the IndustrialSQL In Settings dialog 4 Save the instrument with the button Fie Edit View Settings Start Layout Cursor Help 1 In the tree view select the All Analog Tags group and locate the SysMinutesRun tag 2 Double click on the SysMinutesRun tag to add it to the Active Tags table A I SysMinutesRun vs Time SysNinutesRun Minule w o9 Time Sec Figure 16 7 IndustrialSQL Data
527. ument AutoRetrace instrument RetraceMode instrument FileNew instrument FileOpen filename instrument FileSave instrument FileSaveAs filename instrument FileClose instrument PrintDisplay instrument PrintDesktop instrument RetraceNow instrument ShowDisplay instrument MaximizeDisplay instrument MinimizeDisplay instrument ShowCursorData instrument CloseCursorData instrument MaximizeCursorData instrument MinimizeCursorData instrument Plot AutoRescale instrument Page instrument AutoLayout AOA AUC UK ORK oO UR Ax c UNIES he ON UR ROS eS x e x e Format single string string single long int string long int integer integer string integer string integer integer string KRAARA UA Poke Format string string string string string Y integer Y Snap Master User s Manual Comments Yes No lowest available channel number highest available channel number list of active channels Internal External lowest active channel number highest active channel number Yes if channel num is active use just number portion Comments Yes No Yes No Yes No Yes No Buffer Full full path and file name full path and file name Screen Copy mode only activates selected page DDE Commands and Parameters Page D 5 Default Settings Topic Item Exec Req Poke Format Comme
528. unt pulses out each time count decrements to 0 Not intended for input channel 9513 Mode D Same as Rate Gen except uses a level Gate to hold off source 9513 Mode E The Connections group defines the actual inputs and outputs of the 9513 counter A 9513 counter has the following inputs and outputs SOURCE GATE OUTPUT Source Defines the signal used to determine when to count T C n 1 uses the Terminal Count event on the previous counter as listed The first counter on the 9513 wraps around to the last counter on the same 9513 Source Inputs use the signal connected to the selected Source input on the termination panel Gate Inputs use the signal connected to the selected Gate input on the termination panel F1 F5 are fixed frequencies set by the Prescaler format Count On Determines the edge direction of the Source signal when a count occurs The edge is specified as either a Rising Edge low to high or Falling Edge high to low Counter Timer Gate Output Page 9 5 Sets the gating condition which determines how the counting function occurs When a Gate condition is defined counting occurs only when the condition is satisfied None means there is no gating High T C n 1 means the gate condition is satisfied when the Terminal Count event on the previous counter is High The first counter wraps around to the last counter on the same 9513 Hi Level Gate means the gate condition is satisfied when t
529. unter 2 to 10000 9513 Setup Configuration O Connections gt gt gt gt gt 9513 Chip Source Source 3 zl Prescale Binary C BCD Count On Rising Edge C Falling Edge FOUT Enabled Gate Hilevel C2 z Source zl Output Always Lo zl Source Divider s Registers Counter Settings e Load Register 0 Hold Register Counter Count C Down Up Function C Internal Pacer T C Reload Load Only C Load Hold C Usage zl Cycle Once C Repeat CMode nN Format Binary CBCD Custom Special Gate C Disabled Enabled Cancel Hep Figure 9 12 Configuring a Custom Frequency Measurement The counter used to measure frequency assume counter 3 should have its Usage set to Frequency then to Custom By selecting Frequency before Custom the 9513 Setup dialog automatically sets the parameters for making a frequency measurement and the Custom usage allows you to edit all parameters By changing the Gate input to Hi Level T C 2 the Gate now is active when a Terminal Count occurs on counter 2 In the Counter Timer Settings dialog select the Custom channel channel 3 from the Channel List The data collected from that channel is in units of Hertz but the value is off by a factor of 100 This is a result of the input clock to the Pacer channel and the Load Register value in this case F1 divided by the Load Register gives u
530. ursor Data table now one for AO and one for A1 3 In the Cursor Data table highlight the first two rows in the Linked column and select 1 from the pull down menu This assigns these cursors to link group 1 Any number of cursors and markers can belong to a link group 4 Move the cursor in the upper plot Notice that the cursor in the lower plot immediately moves to the same X axis location and tracks along with the movement of the cursor you are moving 5 Move the cursor in the lower plot Notice that the cursor in the upper plot also tracks with any changes in the linked cursor Disk I O Page 4 1 Chapter 4 Disk I O 4 1 Data File OSA A ZR ERTTOETTTTITT EE 4a i 4 4 Tutorial Saving Data To Disk scccssssssssscssecssscsesssscscesssscscesssscscssssccsesssscscssssssesssscssssssscssscssscsssssscssssssccseeese b 12 4 5 Tutorial Reading Data From Disk 14 eee eee esee rete eee eren e esee eene sees ens ese ens esse sons see sess ese esnsssseseose see sesseseeseseeces be Ld 4 6 Data File Formats 4 ceres sees seen eee en setenta seta sets sets set en sse sns se snas essa esos sse sns sess se sons esses essa sess se sssesosseessscessecesss Eo L5 4 1 Data File Overview Snap Master reads both binary and exponential also called ASCII or text data files in a number of formats There are three native file formats Standard Binary Fast Binary al
531. us And Command Bar t e r e aaa aae rtea nre eene nene nennen eee ee nennen nennen eene nentes nn n kerne seen ein 2 12 Ae M et C 2 13 GUE MIST zo a a E e tease e E EN RS 2 14 Instrument Construction Guidelines Frame Characteristic S5 eoe ertet a ee te ext ect e e ee lee a ee Rx 2 4 Tutorial Creating Your First Instrument eeeee eee eese eese eene tense ense sense eenssessssesnsseeessess 27 16 Creating New Instr ment 3 eer ete recte eerie ete pet pit edel e eee eere Pee petu ea e tex Placing and Connecting the Elements Running the Instrument sentner ai eE en nennen tene en tnter e nnne eren nenne nene rennen nnne 2 5 A D Demo Element eese essere eene entente sten sten sten sten sten sten seen seen seen seen seen seen seen seen EPERE n a 27 20 A D D mo Settings ence eerte ne eie o tete ee tee e etr p t eg ete ete dote gend 2 20 2 6 Tutorial Changing A D Demo Parameters e eee esee eese ee eee en eee eene ese ees esee esses osse ssesesssseseesesss 2 21 Changing the Sample Rate iue ane hqiteie titi teet nre bod tei 2 21 Changing the Frame Length 3 2 imp Ier erbe PEDE OPERE eph 2 22 Stopping the Instrument Automatically Running the Instrument Chapter 3 Display 3 1 Display Window Command Batiaisiantannisontsnni son Sani aonueannd Sonsannisaneannn Gotins sine bute Scrol Bates sets E EE Me E ea NEM
532. use extended memory If you encounter problems with data acquisition try removing all expanded memory emulation programs from the CONFIG SYS file For more information about extended and expanded memory refer to your DOS or Windows manuals Getting Started 386 Enhanced Mode Page 1 7 SHARE EXE If you have installed the Data Acquisition Module you may need to install SHARE which comes with DOS in order for the Sensor database to operate correctly If you receive the error message Is SHARE loaded when adding a Sensor element to the instrument add the following command to your CONFIG SYS substitute the directory where your copy of SHARE EXE is stored INSTALL C DOS SHARE EXE The following CONFIG SYS and AUTOEXEC BAT files are the bare minimum requirements for Snap Master to operate correctly If you are using other software programs your routines may differ slightly When calling for technical support you may be asked to either fax a copy of your CONFIG SYS and AUTOEXEC BAT files or you may be asked to try the following files For more information on these commands refer to your DOS and Windows manuals CONFIG SYS AUTOEXEC BAT DOS HIGH UMB ECHO OFF DEVICE C HIMEM SYS PROMPT p g FILES 30 PATH C DOS C AWINDOWS BUFFERS 30 STACKS 9 256 Windows 3 1 has two operating modes Standard Mode and 386 Enhanced Mode For Windows 3 11 and higher including Windows for Workgroups only 386 Enhanced Mode is available If yo
533. ut Element Analysis Element Output Element Figure 2 11 General Data Flow In Instrument Snap Master Basics Input Elements Analysis Elements Page 2 11 Input elements bring data into the instrument 2 ex S i m CTH IN fk ES a Sensor Signal Conditioner Wave Generator Analog to Digital Input Digital Input Counter Timer Input External Box In Disk In DDE In Integrated database of sensors and transducers which scales voltages to engineering units The Sensor Database also a calibration history Controls supported software programmable signal conditioning hardware Generates fixed function and arbitrary waveforms Receives analog data from A D hardware When placed in an instrument the element name changes to the model of the hardware Some hardware may use another icon Receives digital data from Digital Input hardware When placed in an instrument the element name changes to the model of the hardware Some hardware may use another icon Receives digital data from Counter Timer hardware When placed in an instrument the element name changes to the model of the hardware Some hardware may use another icon Receives data from generic external hardware devices such as RS 232 hardware Reads data stored in a file on a floppy hard or RAM disk Reads files written in binary and ASCII formats as well as Snap Series for DOS files Receives data in real time from othe
534. utput channel Output Specifies the output channel on the D A device This column is not editable The value of the analog output channel is equal to the Input channel as long as it is within the output range of the D A converter If the value is outside the range of the D A converter then the analog output channel will go either to its minimum or maximum value depending on whether the input is greater than or less than the output range Inactive State Specifies the voltage output by the D A channel between frames and when the instrument stops Enter a value within the output range of the channel or type HOLD to maintain the last value of the frame Device The Device section lists the currently installed devices and their device numbers Because Snap Master supports multiple hardware devices running simultaneously each piece of hardware is assigned a unique number Hardware that has multiple functions such as A D D A and Digital I O uses the same device number By default each time you include a new element in an instrument device 1 is selected To use a different device select the proper device number from the list When the Status Messages check box is selected run time information about the element is sent to the Status Log Under normal operation this option should be turned off If an error is encountered during operation of the instrument the message will be sent to the Status Log regardless of the Status Messages sett
535. val SensorID NextCalDate SensorID NumHistory instrument instrument instrument instrument instrument instrument instrument instrument instrument instrument instrument instrument instrument instrument instrument instrument instrument instrument instrument instrument instrument instrument instrument instrument instrument instrument instrument instrument instrument instrument instrument SensorID CalHistory RowNum instrument SensorID ScalingInfo RowNum instrument DependentRange E X c 6 NORRCKON NUR Req RRR RRR RMR OXON DNO ON OU OON Poke RRA KR KRRARK AK RAR RRA RR Format string integer string string string string string string string string single single single single string single single string single string long int string integer string string Page D 13 Comments full path and file name full path and file name unique sensor ID existing sensor ID Assigned All total number of IDs in database returns specific ID when view All date MM DD YY date MM DD YY number of history entries for the sensor ID date MM DD YY of specified history comma separated string with Factor Offset InMin InMax InUnits OutMin OutMax OutUnits Factor Offset Input Output Notes Replace SensorID with a valid sensor ID from the database For example to get the input units of sensor F 59 to psi the Request item is F 59 InUnits
536. value goes below 0 volts the instrument stops automatically Note the message in the Display window s Status Bar If you open the Status Log you will find the Channel AO below 0 Stop test message we specified Status Log 11 11 97 10 35 29 AM Channel AO below 0 Stop test iz Save As Clear Help Figure 13 7 Status Log With Message From Command Element 13 4 Tutorial Subroutines and State Variables This tutorial illustrates how to use subroutines and state variables This time we will process a more complex set of instructions Our goal is to stop the instrument the third time channel AO goes above 4 5 volts Defining The Epp BEE i File Edt View Settings Help Equation Table ee ae esp S S Equation Definition rd 156 endif iz 11 11 97 103612 AM Figure 13 8 Command Equations with Subroutines and State Variables Before we start the new equations let s clear the equations from the previous tutorial 1 In the Command element window select the File menu New Equations command 2 Position the selection box in the Equation Definition column of the first row With the keyboard type Sub IncrementCount then press ENTER IncrementCount is the name of the subroutine used to add one to the number of peaks encountered in the test We will call this subroutine later from the main code Command Page
537. vides the data which many Clients can access This is analogous to a regular network server which provides a core of files that can be accessed by a number of workstations or clients Just to make sure the DDE Out link is on the clipboard let s copy it again Dynamic Data Exchange Page 6 19 1 Open the DDE Out Settings by double clicking on the element DDE Out Settings DDE Items Channel A0 Item data a 1 xLabel 2 xUnits points 3 rate frameNumber X Copy Link To Clipboard Block Mode Data Points Per Block 10 Points Cancel Help Figure 6 17 DDE Out Settings 2 Select channel AO from the Channel list 3 Select data from the Item list 4 Set the Data Points Per Block to 10 points 5 Press the Copy Link To Clipboard button 6 Press the OK button to close the dialog box 7 Switch back to the Window s Program Manager open the Main group and open the Clipbook Viewer application the icon looks like this The Clipbook has two parts the Clipboard and the Local Clipbook On the Clipboard you should see the text Snap MasterlC SM DEFUSER DDEBLOCK ins B A0 data which is the information used for the DDE link In order to share this information with another computer we need to copy it to the Local Clipbook 8 Select the Local Clipbook option from the Window Menu of the Clipbook viewer To add an item to the Local Clipbook we simply need to perform a Paste command When you paste to
538. vst AO vs Time Ch 2 Ch 3 Ch 4 Ch 5 Ch 6 Figure 3 30 Multiple Display Types 7 Press the Close button Even though there is a plot of AO vs A1 for the Y X plot let s look at how the basis channel for the X axis is set To do this we will use another mouse shortcut to open the X Axis Settings 8 Right click on the Y X plot and select the X Axis Settings menu command X Axis Settings Label Voltage Volts I Show Label V Use Default r Scale r Major Divisions Iype Linear Major Divisions 5S Logarithmic Show As Vertical Grid M hOewe u x Tick Mak Location Y 0 M Auto Clear E Iv Show Axis Values Range Minimum and Maximum M Default Scale C All Major Divisions Minimum 10 Volts Maximum 10 Volts Minor Divisions Minor Divisions 2 Format Default Ed nor El Show As C Tick Mark Significant Digits fi 3 ars Cancel Help Figure 3 31 X Axis Settings for Y vs X Plot 9 Select channel AO from the X Axis Channel list The Channel specifies the basis for the X axis or the independent variable In this example we want channel AO to be the basis for the X Axis 10 Close the X Axis settings by pressing the OK button 11 Press the button Page 3 34 Changing Other Plot Components Snap Master User s Manual Display Page 1 Bee Fie Edit View Settings Start Layout Cursor Help E ES ES rs en ca E
539. wn Functions 4 eres sees eese e eene seen en sse ens se tns sess sess seen sse snssesssesesseessseesseceses 12 40 Analysis 4h Frequency Analysis This chapter describes the functionality of two elements the Analysis element which processes time domain data channels and the Frequency Analysis element which processes the magnitude portion of frequency domain data channels Functionally the elements are the same with the exception of the type of data they process This element is included with the Snap Master Waveform Analyzer SM WA module The Analysis element performs calculations on time domain data channels from other elements The built in functions include arithmetic trigonometric statistical calculus logical and filtering In addition user defined functions can be defined which combine the built in functions Analysis Untitled Of x File Edit View Settings Builder Help 2214 3 carey d ET ov n Run Comments Equation Definition Label Units 1x prev and next point less than current point m i CILE NNNM C define peakly illz TIlkvlandlet lacy y 0 3 f i 4 H fuse custom peak function jR peak AQ 5 iindwhenR isnoO AADO B Count peaks Rn A E LL zd integrate btwn 3 amp 7 peaks P intafrange find H2 2 9 find R2 gt 6 9 A0 integration 8i i i
540. xample RO log A0 The Logarithm function takes the base 10 logarithm of the current point in arg1 In arg1 Example RO In A0 The Exponential function takes the natural base e logarithm of the current point in argl Trigonometric Functions Cosine Sine cos arg1 Options d Degrees r Radians g Grads Examples RO cos A0 RO cos r AO The Cosine function takes the cosine of the current point in argl sin arg1 Options d Degrees r Radians g Grads Examples RO sin AO RO sin r A0 The Sine function takes the sine of the current point in argl Page 12 14 Tangent ArcCosine ArcSine ArcTangent tan arg1 Options d Examples Snap Master User s Manual Degrees Radians Grads RO tan AO RO tan r AO The Tangent function takes the tangent of the current point in argl acos argl Options d Examples Degrees Radians Grads RO acos A0 RO acos r AO The ArcCosine function takes the inverse cosine of the current point in argl asin argl Options d Examples Degrees Radians Grads RO asin AO RO asin r AO The ArcSine function takes the inverse sine of the current point in argl atan arg1 Options d Examples Degrees Radians Grads RO atan AO RO atan r AO The ArcTangent function takes the inverse tangent of the current point in arg1 Analysis and Frequency Analysis Page 12 15 Calculus Functions Diffe
541. y Data Frame Header Binary Data Fast Binary Data Format FBDF files have two main differences from the Standard Binary data files the data is not scaled and the data in each frame starts at a cluster boundary which is a property of the disk s format and is specified by the CLUSTER SIZE variable FBDF files also have an additional CAL BLOCK parameter in the File Header This is a binary block of data dependent on the source of the data stored in the file and is required for rescaling the raw data on playback in Snap Master FBDF files have the same structure as the Standard Binary data files except that the data in each frame begins at a cluster boundary The remaining cluster space between the file header and the actual data is filled with zero values Also if a data frame does not fill an complete cluster then the remaining space is also filled with zeros These zero values do not affect the actual data stored in the file The organization of an FBDF file is as follows File Header Frame Header for Frame 1 Zeroes until the cluster boundary Raw Data Frame Header for Frame 2 zeroes until the cluster boundary Raw Data etc Disk I O Comma Separated Variable Data File Format Sample CSV Data File ASCII Plotter Data File Format Sample ASCII Plotter Data File Page 4 21 Comma Separated Variable or CSV files are very popular for importing and exporting data between programs Each of the variables or cha
542. y Specifies the frequency of the waveform Amplitude Specifies the peak to peak amplitude of the waveform DC Offset Specifies the offset from 0 volts for the resulting waveform Phase Specifies the phase shift of the resulting waveform Duty Cycle Specifies the amount of time the function is at its maximum value within one complete cycle Tra pezo i d Trapezoid Settings Trapezoid Parameters Frequency 1 Hz Amplitude 10 Volts DC Offset 0 Volts Phase f Degrees DutyCycle 50 x Rise Time p mSec Fall Time p mSec cen _ nep Figure 5 11 Trapezoid Settings The Trapezoid function produces a waveform which uses defined transition times to oscillate between its minimum and maximum values The slope of the transition times is defined by the Rise and Fall Time settings Frequency Specifies the frequency of the waveform Amplitude Specifies the peak to peak amplitude of the waveform DC Offset Specifies the offset from 0 volts for the resulting waveform Phase Specifies the phase shift of the resulting waveform Duty Cycle Specifies the amount of time the function is at its maximum value within one complete cycle Page 5 8 Triangle White Noise Snap Master User s Manual Rise Time Specifies the amount of time when transitioning from the minimum to the maximum value Fall Time Specifies the amount of time when transitioning from the maximum to the minimum value Triangle Settings
543. y generate data frames until the user presses the Stop button To have the instrument generate a specific number of data frames select the Stop After option and type the number of frames in the Stop After text field Define the current parameters for the selected waveform stage Page 5 10 Stage Length Snap Master User s Manual Set Stage Length Frame Settings Sample Rate 1000 Total Duration 5 Used 0 Total Points 5000 Used 0 C Duration 5 Sec Available 5 Stage Length t of Points 5000 F points Available 5000 pes _ ti Figure 5 15 Stage Length Settings Each channel in the Wave Generator element can be composed of multiple waveform stages to create a customized waveform Each stage is set up using the waveform parameters and duration with the composite waveform for the channel controlled by the order of the stages in the table By default each channel has one waveform stage which lasts the duration of the frame 5 3 Tutorial Creating A Sine Wave Building the Instrument 5 Wave Generator B Display Figure 5 16 Instrument for Wave Generator Tutorial 1 Create a new instrument with the a button or select the File menu New Instrument command in the Snap Master workspace 2 Place the Wave Generator and Display elements in the instrument 3 Activate Pipe Mode with the button or select the Element menu Pipe Mode command 4 Connect the Wave Generator elem
544. y not have the wide range of applications as the main elements they often add very useful functionality to your instrument Most of these elements are a direct result of customer feedback so if you have an idea for a utility element let us know 15 1 Relay z This element is included with all Snap Master modules The Relay element uses the value of an incoming signal to effectively connect and disconnect data pipes at run time Think of the Relay element as a data driven switch to determine what data is passed to downstream elements When the switch is activated then all data from the selected channels are sent down the pipe to the rest of the instrument with a new element letter but the same channel number Relay Settings r Configuration Channel List Driving Channel A0 z 1 3 r Frame Settings Use Defaults Sample Rate 100 Hz G Duration f2 Sec Auto Toggle Channel Value C of Ponts 200 Iv Status Messages Cancel Help Figure 15 1 Relay Settings NOTE When using the Relay element you must pay special attention to how your instrument is configured As a general rule you should only put Output elements Display Disk Out etc after the Relay element The only times you can put Analysis elements after the Relay is if the Relay element will be triggered at least once for every frame on the Driving Channel If the Relay element does not trigger before the end of the Driving Channel s frame some Analysis ele
545. y window wait until the A D has received the correct trigger condition before it begins to plot data You may want to decrease the amplitude of your signal to below 2 volts to see the Display waiting then increase the amplitude to satisfy the trigger condition If the Display does not receive the trigger condition pressing the ESC key will manually trigger the instrument Data Acquisition Page 8 17 8 6 Tutorial Acquiring From Multiple Devices Up to this point our instruments have operated with only one input element Because Snap Master has the capability to accommodate multiple input sources operating at different sampling rates we can now look at acquiring data from multiple input elements in an instrument Depending on the configuration of your hardware you can operate multiple input devices within a single instrument The inputs can operate at different sampling rates and have different frame sizes This is particularly useful when you want to acquire different types of data at both low and high speeds simultaneously This tutorial is written for two A D devices but will work with any two input elements such as an A D and a Digital In an A D and an RS 232 In two RS 232 In elements etc If you do not have multiple devices installed in your computer you can use the A D Demo as your second input element Building the A D R D Instrument 4 4 D Board B amp D Board C Display D Disk Qut Figure 8 16 Instrument with Mu
546. you use special ID numbers for your mythical sensors Input Min Specify the value you want for the default Y axis minimum Input Max Specify the value you want for the default Y axis maximum Eng Units Specify the input channel units Output Min Specify the same number used in Input Min Output Max Specify the same number used in Input Max Out Units Specify the same units used in Eng Units Data Acquisition Page 8 1 Chapter 8 Data Acquisition 8 1 Analog Input A D cssccsssscsssscescscssecssecscsssnsssssesscnssecssssssscsscnsssssesscnsssssnssssscssonssssscsscscsssonsssesesscssssssssssssessonees OF L 8 2 Menu COMMANAG ssccccsscssscsssecsssevsesecssssscnsssesssscnsssssnsssssssssnssscsssscnsssssssssssessonssscssssenssessssssescssonssssscsscnssssscssseseses OMA 8 3 Digital In mE 8 13 8 4 Tutorial Acquiring Analog Data P EK 8 5 Tutorial Using Triggers to Start Acquisition 1 eee eese esee eese ee eren ee eene seen essen osse soss esee ensse se ssssseeesessecess D LO 8 6 Tutorial Acquiring From Multiple Devices cse eee eee esee eene e eee een eee eene seen sese sess esos eosss se soose see sessesesssseeces eI 1 7 8 7 Tutorial Acquiring Digital Data cesse eee eese ee eere e eee een eee eene seen esses ens esee ens sees ens esses soos eese sesso sssseeesesseeess 9 21 ID eccccce ID The next few chapters d
547. ype of Zoom In command that resets the Y axis range so that all data in memory can be shown in the plot The Auto Rescale function scans through the available data in the plot depending on the Retrace Mode and resets the Y axis so the minimum and maximum values are shown After you select the Auto Rescale mode the mouse pointer changes to OF Select the plot you want to rescale by positioning the mouse pointer over the Display region and pressing the left mouse button Remember that the Retrace Mode affects the ranges displayed because each mode addresses a different amount of data Refresh the data on the current Display page using the current retrace mode which is selected in the Settings menu Cursor Data Bik File Edt View Help Ptit X Value Units Y Value Units Channel Label Type Slope Pg Plot Title Show Marker it 4 207 0 503906 Sec 701516 Vols Voltage Bel i 13321566 1 Yves T Yes i14 0 we NS Figure 3 17 Cursor Data Window The Cursor Data table opens when you place a new cursor or marker in the Display window It can also be opened and closed using the button in the Display window command bar There are two places where the Cursor Data table appears in the Display window or in its own window To change the window where the table appears right click over the table and select Toggle Location from the pop up menu When the table is in the Di
548. yquist frequency To have a maximum of 1 contamination of data by aliasing the 40dB frequency of the filter must be less than half the sampling frequency For a maximum of 0 1 contamination the 60dB frequency of the filter must be less than half the sampling frequency e Analog filters always cause some phase or time shift between input and output If different frequencies are shifted different amounts of time non linear phase shift the time history of the signal is distorted Some filter designs provide linear phase shift or constant group delay This means that all frequency components are shifted by an equal time thus not distorting the data even though the whole signal is shifted in time If the signals in different channels of a multi channel system are phase shifted differently you cannot compare event times accurately The specification for an anti aliasing filter might be flat within 5 up to the maximum data frequency of interest and at least 40dB attenuation at half the sampling frequency and linear phase shift or constant group delay in the data frequency range This may require a higher sampling rate or a sharp cutoff anti aliasing filter Selection of sampling rate and anti aliasing filter must be coordinated and often require an economic tradeoff between a more expensive high speed A D converter and a more expensive sharper cutoff filter Also in multi channel systems you may want to specify a maximum var

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