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CoCo-80 Basic DSA User`s Manual - C

1. A special data compression algorithm is developed in order to save the storage space It only applies to time stream recording For uncompressed data use following formula to calculate the total time duration that you can record Total Installed Flash Memory in Bytes Total Channel Enabled Recording Time in Seconds Sampling Rate 8 Bytes 1 2 Or Recording Time in Seconds Total Installed Memory in Bytes Total Channel Enabled Sampling Rate 8 Bytes 1 2 For example if you enabled 6 channels the sampling rate is 100 Hz with 4GB memory installed 76 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Recording Time in Seconds 4GB 6 100 8 1 2 4 1024 1024 1024 6 100 8 1 2 745654 sec 207 hours When data compression is used the storage space will be doubled The spectrum dynamic range of compressed data will be reduced to about 100dB If the storage space and downloading time is not an issue for your application then data compression should not be used The figure below illustrates the difference between the concepts of Display Run Hold Time Stream Record Stop and Signal Save The Display mode is independent of the Record or Save functions When you change the Display mode between Run and Hold it has no effect on the Save or Record functions That means that time streams can continue to be recorded when the display is in Hold mode E Run Hold Rec Stop
2. CRYSTAL N instruments 000060 USER S MANUAL Select the View Mode The View Mode defines how the data will be displayed on the screen To change the view mode select View Mode for Current Trace under the Param Button 200 Nm 400 Om 400 m DUU Dm Color Mapf Maximum Value Trace and Minimum Value m Figure 116 View mode Signal Plot displays a graph of the plot vs time or frequencies Current Value shows a numerical display of the current value of the signal Peak Value Pk Pk Value Maximum Value Minimum Value and Averaged Value show a numerical display of the results of the current data block 122 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL 5 TRANSIENT CAPTURE AND HAMMER TESTING This chapter will demonstrate how to use CoCo to conduct hammer testing Hammer testing refers to impact or bump testing that is conducted using an impact hammer to apply an impulsive force excitation to a test article while measuring the response excitation from an accelerometer or other sensor This type of measurement is a transient event that usually requires triggering averaging and windowing First let s briefly review the Transient Capture function on CoCo Transient Capture Transient Capture is one of the most common used functions for dynamic data acquisition In CoCo the Transient Capture is implemented by setting up the Acquisition Mode Acquisition Mode defines how to transf
3. w t x t where x t is the original data and x t is the data used for the Fourier transform Step 2 87 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL The FFT is applied to x t to compute X K as described above Step 3 Averaging is applied to X k Here Averaging can be either an Exponential Average or Stable Average Result is Sx Sx Average X k Step 4 To get a single sided spectrum double the value for symmetry about DC An Amplitude Correction factor is applied to Sx so that the final result has an un biased reading at the harmonic frequencies Sx 2 e Sx AmpCorr where AmpCorr is the amplitude correction factor defined as N 1 AmpCorr gt w k k 0 where w k is the window weighting function This correction will make the peak or RMS reading of a sine wave at specific frequency correct regardless of which data window is applied For example if a 1 0 volt amplitude 1kHz sine wave sampled at 6 4kHz is analyzed with a Linear Spectrum with Hann window you will get following the spectral shape Li SIG0035 BLOCKIch1 0 032 1 032 0 033 0 034 0 034 0 035 Time seconds amp SIG0034 AP Sich 20 000 0 000 20 000 40 000 4 50 000 50 000 dB V 0 peak 400 000 4 120 000 0 000 SO0 000 1000 000 1500 000 2000 000 Frequency Hz m Figure 80 Sine wave with Hanning window applied to the spectrum The top picture is the dig
4. Time Stream Recording Setup Signal Snapshot Save Setup m Figure 108 CoCo Analysis Parameters selection display Block Size the block size of the time block signals Average Mode Exponential Linear or Peak Hold applied to frequency domain power spectra averaging Time Linear and Time Exponential applies to time domain averaging Average Number the Average number of linear averages When exponential average is selected as the average mode 1 Average Number is used as the exponential factor Window Type type of data window The selection candidates of these fields are defined in the CSA Editor That is the maximum sampling rate maximum number of input channels etc are defined when you create the CSA For example if you select a Maximum Sampling Rate of 1 KHz in the CSA Editor then higher sampling rates will not be available on the CoCo device If a higher sampling rate is required then you must modify the CSA and download it to the CoCo Although this behavior may seem limiting it should be noted that it allows the user to choose exactly the analysis functions and optimize the performance of the CoCo device to suit your specific needs and is one of the unique features of the CoCo system Set the Spectrum Type To set the Spectrum type select the Display Preferences under the Param Button and choose from the list 117 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Dt SMEGSOFEMENEL Dsplav
5. After you connect it press Setup button and click the Update icon The CoCo 80 will first check the connection status and then a connection will be established 53 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Internet Crystal Instruments Server m Figure 54 Network connection for CoCo 80 update After communication is established the CoCo 80 will check with the server to verify if the software subscription is valid If the CoCo 80 is in the valid software subscription period it will then check the latest software components available on the server and download them to the CoCo 80 after the user s approval Two types of software components can be updated e CoCo 80 application software e CSA projects The CoCo 80 user interface will always ask the user s confirmation before the software is downloaded When the new CoCo 80 application software is downloaded you will be asked to confirm to overwrite the old version with the new version Then the older version will be overwritten 54 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL New components were Found please select what you need to download k DSP Bin Files i1files Download Download m Figure 55 On line update detection status screen When new CSA projects are downloaded if the new CSA files take the same file name as the old ones the old CSA files will be renamed to the CSA files with se
6. FIGURE 15 WINDOW AND TRACE TE UE 21 FIGURE 16 EDIT WINDOW SCREEN IS USED TO ADD DELETE WINDOW AND ADD SIGNALS TO EACH TRACE 22 FIGURE 17 IN SCREEN OF TRACE AND WINDOWS SETTING DIFFERENT VIEW MODE CAN BE SELECTED 22 FIGURE 18 PARAMETER SETTINGS MENU E 23 FIGURE 19 LEFT INPUT STATUS RIGHT INPUT CHANNEL TABLE jisssvsssnsssssiassianundiscaadalanaidiensivasnsinsldenstnaisilaiuinnddncusnuceanesstdesietans 24 FIGURE 20 APPLY BUILT IN DIGITAL INTEGRATION OR DOUBLE INTEGRATION unn 25 FIGURE 21 SELECT THE TACHO MEASUREMENT FOR CHANNEL Liu sssssennsinezeasaveaatannsnsdinnvoraastennyntsanineinrendaerainanieanenanens 25 FIGURE 22 OUTPUT CHANINER SOIREE TT 26 FIGURE 23 ARBITRARY WAVEFORM SEI E 27 POORE TE SE TOR gist ba waateetsatenatvaa neuen vent E A A 28 FIGURE 25 ANALYSIS PARAMETERS SEP SCREEN Lavrans 30 FIGURE 26 TRACE NAVIGATION BUT TO E 32 FIGURE 27 CURSORS CAN BE ADDED TO A TRACE E 32 FIGURE 25 CURSOR EE 33 FOURE NERE siracinniieesran ni 34 FIGURE 30 MULTIPLE CURSOR DISPLAY crvgesciaivenua aire a E EE E EE O O EON 34 FOURE S ETOP S CREEN e tre ter rrr errr err eT er rr eT er rrr re ere Tr err rrr rt errr rrr TT 35 FIGURE 62 SU BOK EEE RE A EA 35 FIGURE 35 SOF UV ARE OP TIO E 36 FIGURE 34 AUDIO SETTINGS INCLUDING VOICE ANNOTATION A eeeescceeeesssceeeeesseeeeeeeseeeeeessaeeeeeessaaeeeeessaeeeeeesaeeeeeseas 36 FIGURE 35 MEMORY AND DSP CPU USAGE sioni rerien aonana na a a ANA ETEA EET Ea NE 37 FIGURE 36 POWER STATUS SCREEN
7. X f Fourier Transform of time history record 85 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Fourier Transform Digital signal processing technology includes FFT based frequency analysis digital filters and many other topics This chapter introduces the FFT based frequency analysis methods that are widely used in all dynamic signal analyzers CoCo has fully utilized the FFT frequency analysis methods and various real time digital filters to analyze the measurement signals The Fourier Transform is a transform used to convert quantities from the time domain to the frequency domain and vice versa usually derived from the Fourier integral of a periodic function when the period grows without limit often expressed as a Fourier transform pair In the classical sense a Fourier transform takes the form of X f oe dt 00 where x t continuous time waveform f frequency variable l complex number X f Fourier transform of x t Mathematically the Fourier Transform is defined for all frequencies from negative to positive infinity However the spectrum is usually symmetric and it is common to only consider the single sided spectrum which is the spectrum from Zero to positive infinity For discrete sampled signals this can be expressed as N 1 X k stier n 0 where x k samples of time waveform n running sample index N total number of samples or frame size k finite analysis frequency
8. 3 3 1995 A1 2001 The tests have been performed in a typical configuration C This Conformity is indicated by the symbol i e Conformit Europ enne 152 COCO 80 BASIC DSA USER MANUAL
9. 86 BEG ig ele lee EEE 86 Rive ed TT EE NE NE 87 FONN 89 Ne osten 1 Ke 90 Ge CUI EE E E E A E 94 Frequency Response and Coherence Funchon 95 BER e e i ee ee ee ee 96 HS AA Se I SG A 96 iii COCO 80 USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL DATA VVIAGOW I OME EE NE NO 98 How to Choose the Right Data Window rrrrnnrvennnvvrnnnvrrrnnvrrnnnvrrnnnvrrnnnvernnnversnnvensnnnesnnnnesnnnnensnnnensnnnesnnnnennnnnenn 99 Guidelines of Choosing Data Wmdows 102 Averaging Bee 4 16 DE EN R aE Ei aa A Ea a Ener aa iea 102 Linear Averaging NN NN NN 102 Moving H Big 1 EN EE 103 Exponential Averaging E 104 FLG 5 0 EE EE N E 104 Time versus Power Spectrum Averaging rrnrrrnnnvvennnvvennnnvennnvvrnnnvnennnnnrnnnnnrnnnnnrnnnnnsnnnnesnnnnesnnnnensnnnessnnnennnnnenn 104 6 osten an Re e 105 Coherence Value Affects Accuracy of Spectra Estimate ccccccceseecssseessseeesseessseeeessseeesseeeessaeessseeeesness 106 Overlap FEO CSS e EE EE aaa aaiae aE a i a a 106 Single Degree of Freedom Gveiem 107 CSA Editor Operation for Spectral Analysis Ae 109 CSA Editor VINN 109 EET DECU EE 110 Auto Power SPE Lundanes menes 110 Freg ency 5 E 111 Select the Signals to Compute annnannnannnnnonnaneenennnannnnnnnnenennsnnnenrnnnennnnrnnsrnnsnnnnnrnnsennnnnnnrrnnrnnnnnnnnnnnnnennneennnnn 112 Editing an Arbitrary WEE OM EE 113 Elle Te EEE EEE ee NN 115 CoCo 80 Operation for Spectral Analysis rrrrnnvrnnnvvrnnnvv
10. F1 will prompt the second page the second page allows you to change the system parameters including audio memory date time connection update welcome owner power digit notation theme and measurement settings Use the arrow buttons to select one of the setting icons and press the Enter button to select it These settings are described below Inpi LIE CH utp ut Displa y About Audio Mema ry Date Time Application Channels Channel Preference a loe s p Acquisition System Self Test Testing Log Connections Update welcome Mode Calibration ei a VC I S Power Digit Mokatian Theme m Figure 31 Setup Screen About displays hardware and software version information software subscription period and calibration status About CoCo 80 246501 Components Version Description CoCo 80 ye Application software for data Gr 1 4 9 ee Sotware eg acquisition and analysis Base Hardware 1 0 1 52 O0MHz Scale Processor USB System il Se Ethernet 5D Card LCD keypad Measurement 1 0 1 4 channel inputs 1 output up Hardware to 102 4kHz sampling Firmware 10 5 _ Device drivers DataFlash 1 0 0 2GB flash memory Software Subscription Period Last Calibration Date m Figure 32 About Box Press the F1 Software Option button the screen will show all installed or uninstalled options 35 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Software Option in Detail Installatio
11. IEPE sensor therefore IEPE is displayed in red and a crossing line Set the Sensor Sensitivity For channel 1 Measurement Quantity Acceleration Sensor Engineering Unit TEEN Sensor Sensitivity 10 mitcmltzsbei Select integration or EN LEE me EE Dbl Integration to Displacement differentiation i EU after integration or differentiation m Figure 20 Apply built in digital integration or double integration Channel 1 is uniquely designed that it can take tacho input To do so simply select the Tacho item under the Physical Quantity for channel 1 Frequency Angular welocitw 7 Current E mass Select the physical quantity et the Engineering Unit Set sensitivity of the sensor 1000 mv j m Figure 21 Select the Tacho measurement for channel 1 Input Mode is used to change the input mode The choices are AC Differential AC Single Ended DC Differential DC Dingle Ended and IEPE 25 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Label is used to change the name of the signal Use the alphanumeric keypad to enter a label name and press the OK soft button to accept it Output Channel is used to define the waveform for the output channel First use the left and right arrow buttons to set the focus When the focus Is set to the left region you can select one of the signal sources Use the up down arrow buttons to select from Sine Triangle Square White Noise DC Chirp Swept Sine
12. IP address automatically function 145 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Connect CoCo 80 to a local network using wireless SD card In this connection case if DHCP server is not installed in the local area network both PC and CoCo 80 must be configured with a fixed IP address with the same subnet mask If DHCP server is installed both the PC and the CoCo 80 can use the Obtain an IP address automatically function AmbiCom WL11 or WL54 SDIO Wireless LAN Card is a compact size wireless card for the SDIO capable PDAs and other SDIO compatible mobile computing device using Microsoft Windows Mobile 2003 and Windows Mobile 5 0 operating system In addition to the slim and ultra lightweight SD design the Wireless SD Card also features secure data transfer and full privacy exceptional range and data rate and meets Wi Fi certification standards for total interoperability with other 802 11b g equipment More information is available at http www ambicom com products wave2net wl54 sdio10 htmli Network Connection Diagnosis The following section describes methods for diagnosing network connectivity from the CoCo 80 or the PC which may be helpful when setting up the network connection Diagnosis from the CoCo 80 side A tool is provided to detect the existing network settings from the CoCo 80 side Push the Setup button and select the Connections icon and press the Enter button the connection status is
13. Prererel ice Ke ae L Display Preferences Parameter Sen Sample Rate Input Channels b Time Domain Auto scrall Output Channel Horizontal Axis of Spectra Linear Acquisition Mode Schedule Setup EUpeak EUrms EL2 Hz EL 5 Hz Analysis Parameters Time Stream Recording Setup Signal Snapshot Save Setup m Figure 109 CoCo Spectrum Type selection display Set the Output Channel Parameters To enable the output channel as a function generator select Output Channel from the Param Button Next select the waveform To set the amplitude and frequency and other parameters move the cursor to the parameter and press the Enter Button to edit the parameter To select an arbitrary waveform first select Aro Wave as the output type then press the Arbitrary Wave Button to choose from all the wave files that are loaded on the CoCo Output Parameters None Sine Triangle Square white Noise pc chirp Swept Sine C Arb Wave iCal m Figure 110 Output parameters Select the waveform from the list on the left and use the Arrow Buttons to move the cursor to the quiet zone duration and peak output level settings on the right Press the Enter Button to edit any of these parameters 118 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Arbitrary Waveform Name Wave 1 Description None Length 1024 Test0 Testl gt 1 i ha Arb Waveform Duration ms 50 Quiet Zone Du
14. SAVE DATA BY PRESSING THE SAVE HARDWARE BUTTON ee 131 FIGURE 131 A 1 KHZ SINE WAVE SAMPLED AT 8 KHZ TOP AND ALSO SAMPLED AT 5 12 KHZ BOTTOM eeververnne 134 FIGURE 132 A SMALL ERROR IN ACCELERATION RESULTS IN A DC OFFSET IN VELOCITY AND A HUGE DRIFT IN RE ICE IV EE 134 FIGURE 133 SENSOR SENSITIVITY WITHOUT INTEGRATION e 136 FIGURE 134 SENSOR SENSITIVITY WINDOW WITH DOUBLE INTEGRATION AND UNITA 136 FIGURE 135 EDM IN VDC MODE SIGNAL ANALYSIS DISPLAY ssssccsassvscssesttcavascnbeadsevensaveiaswncentsutensauatiinanaiiascadersaiacatlasntincnins 138 FIGURE 136 ETHERNET CONNECTION STATUS wosscincassaatennasnsisniasiatiannnsaaabansyinnsioniamsnataamaslnttnnyaceastannseaiioubavausnanusseteenadawssananinstins 144 FIGURE 137 SPECIFY A STATIC IP ADDRESS FOR THE ETHERNET CONNECTION 144 FIGURE 138 USB CONNECTION STATUS DISPIA E 144 viii COCO 80 USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL _ FIGURE 139 ETHERNET CONNECTION STATUS SCREEN sserernevsrnsnsrnsnsnnsnnnnsnsnnsnnnnsnsnnsnsnneneeneneeneneeneneneneeneneeneneeseneeneneene 146 _ FIGURE 140 EDM NETWORK CONNECTION STATUS SCREEN cccsccececcececcececcececcececcececceteccececceteccsteccetsceccscacees 147 ix COCO 80 USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL 1 INTRODUCTION CoCo 80 is a handheld data recorder dynamic signal analyzer and vibration data collector that is ideal for a wide range of industries including m
15. TRIGGER WINDOW WITH ACCEPT OR REJECT OPTIONS esrrnevrnnvvrnnvvnnuvvnnvvnnnuvnnnnvnnunvnnuvsnnuvnnnnvnnunvnnnsennusnnnneen 75 M FIGURE 70 ILLUSTRATION OF THE DIFFERENCE BETWEEN DISPLAY RUN HOLD TIME STREAM RECORD STOP AND NNN EEN 77 E FIGURE 7LSIGNALSNAPSHOT SAVE SETUP E 78 M FIGURE 72 SIGNAL SNAPSHOT SAVE SETUP cccccsecccsscccscccessccnscccnscccssccassccacsccsccessecussccasccesseeessecasecesecececenseeaeeees 78 M FIGURE 73 FILE REVIEW SCREEN FOR RECALLING SIGNALS cccccseccssccccscccscccnccccssccassccscccsccensccassccasecensecesseeasees 81 M FIGURE 74 RECALL SIGNAL POP UP MENU 82 M FIGURE 75 RECALL SIGNALS FROM THE TRACE MENU 82 E FIGURE 76 UN RECAULE SIGNAL EE 82 M FIGURE 77 RECALLED SIGNALS APPEAR WITH FILE NAME PREFIX cccsccccsscccssccssccnscccnscccssccessccsccessccesseceeeees 83 M FIGURE 78 LIVE SIGNAL OVERLAID WITH RECALLED SIGNAL ersvernevernevvnnevrnnvvrnnvvnnnvvnnnvnnnuvnnnnsnnunvnnnvsnnuvnnunsnnunvnnnvennusnnnneen 83 M FIGURE 79 RPM LIVE SIGNAL OVERLAID WITH RECALLED SIONAL eee eeecccsccccsscccscccscccsscccssccessccsccesecesseeaeeees 84 M FIGURE 80 SINE WAVE WITH HANNING WINDOW APPLIED TO THE SPECTRUM 0 ccseccsseccscccessccssccessccassees 88 M FIGURE 81 HANNING WINDOWING FUNCTION APPLIED TO A PURE SINE TONE revervnvrrnevrnnevennevennvvnnnvvnnuvsnnvvennusvennneen 89 M FIGURE 82 FLOW CHART TO DETERMINE MEASUREMENT TECHNIQUE FOR VARIOUS SIGNAL TYPE
16. VDC Enterprise Allow multiple users working on the same database on view Detail PA Premium All post analysis functions will be enabled View Detail Spider DSA Dynamic signal analysis functions of Spider View Detail OK I Cancel Software Renew Period this is the time period that this EDM installation can be upgraded using the current installed License Key When the time expires the EDM software will still be functional but cannot be updated Software Activation Period this is the time period that this EDM installation can be used using this License Key The CoCo DSA Mode of EDM The EDM Software functions as both the means of transferring date from the CoCo 80 to the PC and also as a data management and analysis tool The main features of the software include transferring data between the CoCo 80 and a PC viewing searching and exporting data to other formats and using the analysis tools to measure signal characteristics Data Transfer After a connection is established between the CoCo 80 and a PC the EDM software manages the transfer of data between the two devices The data includes recorded time streams saved signals and CSA projects When EDM detects the connection the software displays a list of the files available for transfer and allows the use to initiate the download to the PC After files are downloaded they can be deleted from the CoCo 80 flash memory to create free space for new data files Data Ma
17. a high signal to noise ration and high dynamic range The integration process in essence will reduce the high frequency energy and elevate the low frequency components If the original signals do not have good signal noise ratio and dynamic range the signals after integration and double integration will have too much noise to use The noise will corrupt the integrated signal 3 The instrument must be able to set two different engineering units one engineering unit for the input transducer and a second engineering unit after the integration For example first the instrument must provide a means to set the sensitivity of the sensor say 100mV g After the double integration the instrument must have the means to set the engineering unit to a unit that is compatible with the integration such as mm The CoCo instrument handles these three issues effectively so you can get reliable velocity or displacement signals from the acceleration measurement or displacement signals from the velocity measurement The CoCo hardware has a unique design to provide 130dB dynamic range in its front end measurement The signals with high dynamic range will create better results after digital integration 132 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Since such build in integration is conducted in the time domain before any other data conditioning or spectral analysis the time streams generated after the digital integration can be tr
18. a0 Device Status USB Connection UnReachable EDM Software on host PC m Figure 138 USB Connection Status Display 144 COCO 80 USER S MANUAL COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Access Code This is a special setup to prevent an unauthorized user from accessing the CoCo 80 on the LAN It also provides a means for the EDM software to access a particular CoCo 80 on the network The EDM requires the CoCo 80 Access Code to access it over the LAN Configuring the Host PC Network Settings H the host system is a PC which is only connected directly to the CoCo 80 using a cross over Ethernet cable you can manually configure the TCP IP settings You can also use the alternate configuration functionality to maintain seamless operations on both office and private networks without having to manually reconfigure the TCP IP settings Choose whichever method best applies to your system configuration and connectivity needs Refer to the Microsoft support website for more information on alternate configuration http support microsoft com kb 283676 Note You must be logged onto the host system as an Administrator in order to change network settings Contact the system administrator to get access to the necessary privileges Connect CoCo 80 to a PC directly using USB client A USB connection is the easiest method to connect the CoCo 80 to a PC This requires the following steps 1 Instal
19. about Spectrum Types see the section entitled Spectrum Types in this Chapter The linear spectrum is saved internally in the complex data format with real and imaginary parts Therefore you should be able to view the real and imaginary parts or amplitude and phase of the spectrum Power Spectrum Spectral analysis is popular in characterizing the operation of mechanical and electrical systems A type of spectral analysis the power spectrum and power spectral density PSD is especially popular because a power measurement in the frequency domain is one that engineers readily accept and apply in their solutions to problems Single channel measurements auto power spectra and two channel measurements cross power spectra both play important roles In power spectrum measurements window amplitude correction is used to get un biased final spectrum amplitude reading at specific frequency In PSD or energy spectral density ESD measurements window energy correction is always used to get an un biased spectral density or energy reading 89 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL To compute the spectra listed above the instrument will follow these steps Step 1 A window is applied x k w k x k where x k is the original data and x k is the data used for a Fourier transform step 2 The FFT is applied to x t to compute Sx N 1 a gt Ne n 0 Next the so called periodogram meth
20. are measuring a deterministic signal with very few averaging the spectrum estimation can be very accurate If the signal has a random nature with partially random or significant measurement noise more averaging must be used Assume the time data is captured from a stationary random process and we calculate various spectra using window FFT and averaging techniques how much we can trust the measured spectra can be measured by a statistical quantity standard deviation Here are a few useful equations to compute the standard deviation of the spectra when linear averaging is used Functions being Standard Deviation estimated Auto spectrum Gxx 1 vn Cross spectrum Gyx 1 Cyx I du Coherence Function 1 Cyx V2 Cyx pet Ai ad Cyx vn Frequency Response Function Hyx 105 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL where nis the average number in linear averaging The transfer function is computed in the cross power spectrum method as presented earlier Assume a signal is random and has an expected power spectral density at 0 1 V Hz The goal of a measurement is to average a few power spectra and to estimate such an expected value If the average number is 1 meaning with no average the standard deviation of the error of such a measurement will be 100 When we average two frames of auto power spectra the standard deviation of the error will become 70 7 When the average number is
21. are captured into block signals by enabling Acquisition Mode Capture1Ch 4 csa Capture1Ch 8 csa Block capture the channel 1 with up to 64k buffer size Linear and Power Spectra APS1Ch 4 csa APS1Ch 8 csa Only calculate the auto spectrum for 1 channel with up to 64K buffer size FFT 4 csa FFT 8 csa Transform the time streams into block signals then apply data window and FFT 63 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Frequency FRF 4 csa FRF 8 csa Calculate the frequency responses Response when channel 1 set as reference and the others as responses CrossPowerSpec 4 csa CrossPowerSpec 8 csa Calculate the cross power spectra when channel 1 set as reference and the others as responses FRF COH 4 csa FRF COH 8 csa Calculate the FRF and coherence when channel 1 set as reference and the others as responses gt 4 8 T a mer Real time DecimFltr 4 csa DecimFltr 6 csa Apply n stage of 2 1 decimation to Digital Filter each input channel to obtain the signals with lower sample rate FIR 4 csa FIR 8 csa Apply FIR Low Pass High Pass Band Pass and Band Stop filters with filter length 67 RemezFltr 4 csa RemezFltr 8 csa Apply Remez FIR Low Pass High Pass Band Pass and Band Stop filters with filter length 67 IIRFItr 4 csa IIRFItr 8 csa Apply IIR Butterworth Low Pass Butterworth High Pass Chebyshev Band Pass and Elliptic Band Stop filters wit
22. be replaced by the user The main battery is used to power the instrument The main battery is a Lithium lon type cell with a capacity of up to 6600 milliamp hours The main battery is located inside the enclosure and can be replaced by opening the lid on the back of the CoCo 80 To recharge the main battery simply connect the AC adaptor between the CoCo 80 and the AC power source The power source must be in the range of 100 250 VAC When the CoCo 80 is turned on a battery capacity symbol is shown on the status bar that indicates the state of charge of the battery 52 COCO 80 BASIC DSA USER MANUAL CRYSTAL Instruments COCO 80 USER S MANUAL m Figure 53 CoCo Battery Battery Charger This is an optional accessory This charger can charge the main battery without using CoCo It is convenient to use this charger to charge an extra main battery while one is in use This charger is designed and made by Crystal Instruments DC DC Converter for Car Cigarette This is a DC DC adapter using automobile cigarette lighter voltage isolated Input 9 30VDC Output 15V 3A 10 With this converter the user can use the power from the car cigarette adapter to support the CoCo CoCo 80 On Line Updates The CoCo 80 application software has the capability to check for software updates from the Cl web server when you connect the CoCo 80 device to the Internet You first connect the CoCo 80 to a local network using regular Ethernet
23. channel x and output channel y Gxx and Gyy are the averaged auto spectrum of the input and output Either power spectrum power spectral density or energy spectral density can be used here because of the linear relationship between input and output so that any multiplier factors will be cancelled out 95 COCO 80 BASIC DSA USER MANUAL CRYSTAL COCO 80 USER S MANUAL instruments Coherence is a statistical measure of the how much of the output is caused by the input The maximum coherence is 1 0 when the output is perfectly correlated with the input and zero when there is no correlation between input and output Coherence is calculated by an average of multiple frames When it is computed for only one frame then the coherence function has a meaningless result of 1 0 due to the estimation error of the coherence function The coherence function is a non dimensional real function in the frequency domain You can only view it in the real format Data Window Selection Leakage Effect Windowing of a simple signal like a sine wave may cause its Fourier transform to have non zero values commonly called leakage at frequencies other than the frequency of this sine This leakage effect tends to be worst highest near sine frequency and least at frequencies farthest from sine frequency The effect of leakage can easily be depicted in the time domain when a signal is truncated As shown in the picture after data windowing truncation distorted the ti
24. corresponding to FFT bin centers X k discrete Fourier transform of x k In most DSA products a Radix 2 DIF FFT algorithm is used which requires that the total number of samples must be a power of 2 total number of samples in FFT 2 where m is an integer Data Windowing The Fourier Transform assumes that the time signal is periodic and infinite in duration When only a portion of a record is analyzed the record must be truncated by a data window to preserve the frequency characteristics A window can be expressed in either the time domain or in the frequency domain although the former is more common To reduce the edge effects which cause leakage a window is often given a shape or weighting function For example a window can be defined as w t g t T 2 lt t lt T 2 0 elsewhere 86 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL where g t is the window weighting function and T is the window duration The data analyzed x t are then given by x t w t x t where x t is the original data and x t is the data used for spectral analysis A window in the time domain is represented by a multiplication and hence is a convolution in the frequency domain A convolution can be thought of as a smoothing function This smoothing can be represented by an effective filter shape of the window i e energy at a frequency in the original data will appear at other frequencies as given by th
25. data and create report PA Basic has FFT spectral analysis and 3D signal display functions PA Premium has all post analysis functions rece SC 9 QRECHaaD O neins eng wine far oet Tell ECH rapte far act Signal Octren ehti Lb X Fraves rm Deng 55 AdiveRecerdrg SOS zept ak ee qa ee i EDM software is registered to a CoCo or a Spider device To activate the EDM software the user must have a License Key EDM software uses a License Key file to enable or disable certain functions License Key is also used to control the Activation Period and Software Subscription Renew period Multiple License Keys can be installed in one EDM installation This allows an instance of EDM runs multiple hardware devices A typical management page for license keys is shown below 139 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL EDM License Key Management 2S aa Hardware Device Serial Number Browse New License Key Spider80 661056 Cacaso Spider80 029220 651028 Savethisticenseker Set as Default Remove License Key Information Software RenewPeriod 01 09 2011 Software canbe updated usingthis LK beforethis date Software Activation Period 01 09 2110 Software can beused using this LKbeforethis date Installed EDM Software Options Type Description View Detail CoCo CA Edit CoCo DSA projects with Configurable Signal Analys View Detail CoCo
26. domain which corresponds a convolution in the linear spectrum we cannot have both a valid amplitude and correct energy correction at the same time Use Figure 82 to select appropriate spectrum types In a Linear Spectrum measurement a signal is saved in its complex data format which includes both real and imaginary data Then is averaging operation applied to the linear spectrum Ina Power Spectrum measurement the averaging operation is applied to the squared spectrum which has only real part Because of different averaging techniques the final results of Linear Spectrum and Power Spectrum will be different even though the same spectrum type is used Spectrum Types selection only applies to Power Spectrum and Linear Spectrum signals Spectrum Types do not apply to transfer functions phase functions or coherence functions Cross Spectrum Cross spectrum or cross power spectrum density is a frequency spectrum quantity computed using two signals usually the excitation and response of a dynamic system Cross spectrum is not commonly used by its own Most often it is used to compute the frequency response function FRF transmissibility or cross correlation function To compute the cross power spectral density Gyx between channel x and channel y Step 1 compute the Fourier transform of input signal x k and response signal y k N 1 Sx gt x k w k e 12r IN n 0 N 1 Sy gt yk we Fann n 0 94 COCO 80 BASIC DSA USER MA
27. exists This is the case when measuring the output of sensor amplifiers A CMV will produce noise in single ended mode AC Differential AC Differential applies a low frequency high pass filter to the input filtering the DC component of the signal The result is a zero mean signal This is most commonly used for dynamic signals with CMV AC Single End AC Single End mode combines the AC filter with single ended mode This is most commonly used for dynamic signals with no CMV such as measuring the output of an amplifier IEPE ICP The CoCo 80 supports IEPE constant current output type for its input channels The built in circuit is powered by a 4mA constant current source at roughly 21 Volts IEPE refers to a type of transducer that is packaged with a built in current source IEPE is an acronym for Integral Electronic Piezoelectric IEPE requires an AC filter so DC measurements are not possible when IEPE is enabled CoCo has a cut off frequency of 0 3HZ 3dB for the IEPE input mode CoCo can automatically detect the IEPE sensor connection when the IEPE input mode is enabled The sensor indication is shown in following three modes A green IEPE sign indicates that the IEPE is set in the channel table and the IEPE sensor is detected a red IEPE sign indicates that the IEPE mode is set in the channel table but the sensor has not been detected This is a faulty mode the empty space means that this channel is not set to IEPE 47 COCO 80 BA
28. filter at 15Hz and ch2 at 50Hz Others are at 1Hz Input Channel Table Sensitivity Input Mode Hi Pass Wa each Label i rood ml AC Single 1582 aov fi BM 2 100 10 e ie Single 10 v Te hr p on 100 rai a VHE ov E h3 tv IFE Single Jine hov Ej SE AC Single 1Hz linv Johs mme ACSngle tHe ov de 1000 melt AC Single Jus tov eh 5 1000 mwyty 1 AC Single 1Hz iHz jow oe CoCo 80 Operation Integration can be enabled in the Input Channel table In CoCo to set up the built in integration or double integration you must set two engineering units The first one is for sensor sensitivity the second for the engineering unit after the integration or differentiation For example you can choose either g or m s as the engineering unit used for the accelerometers After the double integration you can choose one from the list of meter cm mm or other displacement units for displacement presentation Example First select the Acceleration or Velocity in the input channel table 135 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Set the Se Measurement Quantity Sensor Engineering Unit gn Sensor Sensitivity 9807 myltgn Select integration or No Integratic differentiation See m Figure 133 Sensor sensitivity without integration Then select the engineering unit of the sensor to be used and set its sensitivity Under the i
29. in displacement Of course the computed velocity and displacement signals are unrealistic They are artifacts of the integration errors In order to remove such a problem caused by inaccurate measurement and 134 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL digital integration a high pass filter can be applied before or after the integration It should be noted that the high pass filter will distort the waveform shape to some extent because it alters the low frequency content of the signal However this effect must be tolerated if numerical integration is used Digital High Pass Filter The most effective way to remove the DC drift effect as described above is to apply a high pass digital filter to the continuous time streams In CoCo a unique algorithm is realized so that even the data is sampled at high rate the high pass filter can still achieve very low cutoff frequency The filter cutoff frequency is specified at 3dB attenuation To remove unwanted signals at or near DC please set up the cutoff frequency of the digital high pass filter as high as possible as long as it won t chop off useful frequency content of your interest To give an example if you are not interested in any frequency less than 20Hz then you can set the cutoff frequency to approximately 10Hz With this setting the amplitude attenuation at 20Hz will be less than 1dB The following picture shows that ch1 sets the high pass
30. long enough to cover the whole transient range or when the signal is exactly periodic in the time frame If the goal of the analysis is to discriminate two or multiple sine waves in the frequency domain spectral resolution is very critical For such application choose a data window with very narrow main slope Hanning is a good choice If the goal of the analysis is to determine the amplitude reading of a periodic signal i e to read EUpk EUpkpok EUrms Or EU nme the amplitude accuracy of a single frequency component is more important than the exact location of the component in a given frequency bin choose a window with a wide main lobe Flattop window is often used If you are analyzing transient signals such as impact and response signals it is better not to use the spectral windows because these windows attenuate important information at the beginning of the sample block Instead use the Force and Exponential windows A Force window is useful in analyzing shock stimuli because it removes stray signals at the end of the signal The Exponential window is useful for analyzing transient response signals because it damps the end of the signal ensuring that the signal fully decays by the end of the sample block If the nature of the data is has a random nature or unknown choose Hanning window Averaging Techniques Averaging is widely used in spectral measurements It improves the measurement and analysis of signals that are purely ra
31. new waveform Export lets you save the arbitrary waveform as a text file which can be opened in a text editor or spreadsheet Import lets you import an arbitrary waveform that is saved as a text file You can also right click on the name of waveform This opens a pop up menu with copy paste delete export and import Finally Right click on the arbitrary waveforms and upload them Then the arbitrary waveforms are ready to be output in CoCo 114 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Tim mi h T HC I Ls H o E Se E 3 arbsignals m Figure 106 Upload the arbitrary waveform to the CoCo hardware Finally click on the Send to CoCo button to save the arbitrary waveform file on the CoCo hardare Validation After the CSA Wizard is complete and the CSA file is created connect the host PC to the CoCo device and press the Validate icon to validate the CSA It may take a few minutes to finish the validation The validation process analyzes the CSA file for internal consistency and estimates the required DSA resources required to run the CSA file on the CoCo device If the Validation passes then press Send to CoCo command in the Validation dialog box to send the CSA project file to CoCo Alternatively you can manually upload it to CoCo The CSA uploaded will be classified into different CSA Application Groups based on the template that was used 115 COCO 80 BASIC DSA USER M
32. or Arbitrary Signal None turns off the output channel When the focus is set to the right you can modify the parameters for that particular signal source etup gt Measurement Qutout Channel None Sine Triangle Square white Noise Swept Sine orb Wave m Figure 22 Output Channel screen For each waveform the parameter settings must also be enters such as range frequency and amplitude Output Channel is a global setting that applies any loaded CSA Apply saves the settings activates the output channel and returns to the previous screen Cancel discards the settings and returns to the previous screen When the Arb waveform is selected you can output an arbitrary waveform file This file must be uploaded to the CoCo 80 through EDM before it can be used 26 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Arbitaryv Waveform Name Testo Length 256 Description Mone Testi R Arb Waveform Durationims 16 I Quiet Zone Durationims 100 Peak Output Level Volt 1 m Figure 23 Arbitrary waveform setup In the arbitrary waveform setup the duration is fixed by the number of points in the arbitrary data file and the sampling rate in use The Quiet Zone is the time with zero output between two arbitrary waveform pulses The Peak Output Level is the normalized maximum volt for the output waveform Regardless the value in the arbitrary file it is always normalized to this
33. or Auto Arm Trigger Auto Arm automatically accepts the data frame into the average and prepares the trigger for the next signal Manual Arm provides a graphical display of the data and allows you to accept or reject the frame into the average Mode Condition Free Run No trigger source is needed Sege after Trigger Single Shot without Trigger Single Shot with Trigger Auto rm Trigger m Figure 124 Trigger Modes for Transient Capture Trigger Source defines which signal to use as the trigger source Only signals specified in the CSA script are available as trigger sources If a signal is not available then it can be added as a trigger source by editing the CSA file and downloading it to the CoCo hardware 128 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL The Trigger Condition and Level Setup define the conditions that will trigger the acquisition You can also edit the high and low level and the trigger delay Alternatively you can change the level settings with the up and down arrow buttons Mode Condition Manual Arm Trigger chi gt High Level Trig Src chi Low Level 1 0 High Level 1 0 ich 1 lt Low Level Falling edge Low Level lt chi lt High Level cht gt High Level OR chi lt Low Level Edit High Level Edit Trig ger Delay Trigger Trigger m Figure 125 Trigger conditions and level setup for transient capture Overlap defines the amount of overlap between fra
34. or LogMag The Log display shows the signal scaled logarithmically with the grid values and cursor readings in actual engineering value The picture below shows the same signal in LogMag 120 COCO 80 BASIC DSA USER MANUAL CRYSTAL Instruments COCO 80 USER S MANUAL m Figure 114 A 1Vpk sine signal in frequency domain with LogMag scaling When GB reference is not specified the dB reference is 1 0 engineering unit In acoustics application the dB reference for the sound pressure value is set to 20uPa The same input signal will result in different dB readings when dB reference is changed Set Acquisition Mode The appropriate acquisition mode should be set to transform the time streams into blocks The details of acquisition mode for transient capture are described in the next chapter Transient Capture and Hammer Test For frequency analysis that use stable and continuous excitation signals use either Free Run or Continuous after Trigger mode in the Acquisition Mode selection For details about setting the acquisition mode refer to the Basic Operation of CoCo 80 Set Overlap Ratio The overlap ratio is set in the Acquisition Mode The overlap ratio setting will only be effective when the Mode is selected as Free run or Continuous after Trigger For triggered transient capture there will be gaps between frames and an Overlap Ratio can not be applied m Figure 115 Overlap Rate selection 121 COCO 80 BASIC DSA USER MANUAL
35. recorded the voice annotations will be played back as well 60 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL After the signal playback is finished the screen will show a message of Waveform playback finished Notice that the recorded signal will be played back at the sampling speed of when it was acquired Inside CoCo the A D converters and D A converter share the same sampling clock Due to this design when the signal is played back input signal cannot be analyzed CSA Configurable Signal Analysis This section describes the Configurable Signal Analysis concept that is the basis for the CoCo 80 functionality and allows advanced users to customize the analysis features to suit individual needs This section gives a brief description that is intended for the basic user It does not describe writing projects for advanced users For more on writing CoCo 80 analysis functions refer to the manual about CSA Editor that comes with EDM host software 61 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL When the CoCo 80 powers up the Welcome screen is shown From this screen the use must select one of the CSA projects loaded on the CoCo 80 When a CSA project is selected the project defines the settings and analysis functions that are computed by the CoCo 80 These settings include the following e Parameters used by the data conditioning functions su
36. second for the linear averaging of the past 1 hour 103 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Exponential Averaging In exponential averaging records do not contribute equally to the average A new record is weighted more heavily than old ones The value at any point in the exponential average is given by yln yln 1 1 a x n where y n is the nth average and x n is the nth new record ais the weighting coefficient Usually ais defined as 1 Number of Averaging For example in the instrument if the Number of Averaging is set to 3 and the averaging type is selected as exponential averaging then a 1 3 The advantage of this averaging method is that it can be used indefinitely That is the average will not converge to some value and stay there as is the case with linear averaging The average will dynamically respond to the influence of new records and gradually ignore the effects of old records Exponential averaging simulates the analog filter smoothing process It will not reset when a specified averaging number is reached The drawback of the exponential averaging is that a large value may embed too much memory into the average result If there is a transient large value as input it may take a long time for y n to decay On the contrary the contribution of small input value of x n will have little impact to the averaged output Therefore exponential average fits a stable s
37. should never apply a voltage that potentially exceeds 40V to the Instrument 3 Review the entire manual before use of the Instrument and its accessories 4 Donot operate the Instrument around explosive gas or vapor 5 Before use inspect the instrument BNC connectors and accessories for mechanical damage and replace when damaged Look for cracks or missing plastic Pay special attention to the insulation surrounding the connectors 6 Remove the cables and accessories that are not in use 7 Use the ground input only to ground the Instrument and do not apply any voltage 8 Do not insert metal objects into connectors 9 Use only the wall mount power supply provided by the Crystal Instruments AC Adapter Voltage Range For external power source CoCo 80 uses a wall mount AC Adapter The AC Power range is 100Vac 240Vac Maximum Measurement Input Voltage Maximum Working Input Voltage 10 V peak Voltage ratings are given as working voltage They should be read as Vpeak for dynamic applications and as V dc for DC applications Max Input Range without damaging the hardware 40Vpeak If Safety Features are Impaired If the instrument is used in a manner not specified by the manufacturer the protection provided by the instrument may be impaired Before use inspect the test leads for mechanical damage and replace damaged test leads If the instrument or its accessories appear to be impaired or not functioning properly do not
38. shown below CoCo G0 Device Status Ethernet Connection IP Address 192 163 1 118 Metwork Status EDM DHCP Serwer Internet Connected CI Server Connected m Figure 139 Ethernet connection status screen The network setting detection shows the following status e Hardware indicates whether the Ethernet USB port or Wireless card inside the CoCo 80 device are functional e IP Address indicates the IP address of the CoCo 80 146 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL e DHCP server indicate whether the CoCo 80 has detected a DHCP server on the local area network e EDM indicates whether CoCo 80 is connected to the EDM the host software on a PC e Internet indicates whether the CoCo 80 is connected to the Internet e Cl server indicates whether the CoCo 80 is detecting the Crystal Instruments server The Cl server is used to host new software to keep the CoCo 80 up to date Diagnosis from the PC The connection between the CoCo 80 and a PC is managed within the EDM software on the PC The EDM software provides connection diagnosis capability The Connection Wizard dialog box will show one of following four connection pictures Please select one of the connection methods that you would like to use USB oneto one connection Cross Over Ethernet Cable one to one connecton Both this PC and the CoCo 60 are connected to LAN using Eth emet This PC is connected to a LAN Co
39. software and the flash memory used to store recorded data This display can be used to monitor the remaining flash memory remaining during field operations When flash memory is full then the data must be downloaded to the PC and removed from the CoCo 80 before more data can be recorded 36 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Storage Status Local Memory Used Space Memory used by Free Space the programs Capacity 465 File Flash Memory Used Space 0 06 GB Memory used ta Free Space 1 50 GB store data files Capacity 1 92 GB Po CPU Usage te 12 56 m Figure 35 Memory and DSP CPU usage Date Time allows you to enter the current date and time so that this information can be included as a file attribute with the data files Connections displays the status of the Ethernet USB Client or Wireless connections The IP Setup soft button allows you to specify a fixed IP address or to use DHCP Update allows the CoCo 80 to check for new software components on the Crystal Instruments server and conduct online software updates at the user s request CoCo 80 must be connected to the Internet using Ethernet or wireless when on line update is performed Welcome shows the welcome screen that lists the available CSA projects loaded on the CoCo 80 and other status User shows the information recorded for the user of the hardware including Name company address telephone and Email and appends
40. system to a user previously set CSA and ne execute it User F1 F6 function Context dependent function soft buttons buttons Status Bar The Status Bar indicates the status of the system m Figure 5 CoCo 80 display Status Bar WS Sepp Navigation indicates the name of the screen or provides information about the analysis such as sampling rate 41 Volume indicates the volume level for the internal speaker Volume for internal speaker defined in the Setup screen Power indicates battery or line power mm Battery status indicates the state of charge or if AC power is connected 1789 System time displays the time defined in the Setup screen Other status such as sampling rate number of averaged frames in spectral processing number of frames acquired will be displayed according to installed CSA Menu Navigation The CoCo 80 is operated by moving between screens entering parameters and initiating commands with the buttons This section gives a brief overview of the menu navigation More detailed information is given in the following sections Startup Press the Power button to power on the unit The initialization screen shows the startup progress When the startup sequence is complete the Welcome screen is shown 12 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Fr mstruments SHIFT button Initialize Binary Information m Figure 6 Startup screen is shown durin
41. the information as an attribute to all data files This information can be edited by selecting it with the arrow buttons and pressing the Enter button Power indicates the status of the power including the Remaining capacity of the battery The Advanced soft button allows you to customize the power settings to optimize the battery life for specific conditions including Automatic mode which maximized the battery life by automatically turning off the LCD and the backlight and Ethernet Maximum Active Mode keeps all components on but uses the maximum power consumption 37 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Houer Current Power Status Power Status External Adapter Charging VES Total Capacity 6600 m h Remaining Capacity 5940 mah Mote Your device will be automatically power off when the remain capacity is less than 5 m Figure 36 Power Status Screen Digit Notation is used to change the format that numbers are displayed on the CoCo 80 The choices include Floating Point Scientific or Engineering notation Digit Notation Digit Motation Format Example Scientific Notation Engineering Motation 1000 10 O 001 m Figure 37 Digit Notation Settings Theme changes the display from black to white background 38 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Display Parameters m Figure 38 Theme Settings Black or White Sty
42. this short Quick Start tutorial you should read the following sections and review the complete Users Manual for a detailed description of the features and operating instructions Important Notice about the Concept of CSA CSA stands for Configurable Signal Analysis The first time you use the CoCo 80 you may wonder why some of the signals or functions are missing when you run the CSA files For example when DefaultTime 4 runs you will find it does not support any acquisition mode any transient capture 8 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL or any spectral analysis You may wonder if this is a software bug The answer is no Whether these features are available or not are determined when the CSA project is edited on the host PC Initially the concept of CSA may appear unconventional to some However this is the base that provides flexibility and powerful capability to the CoCo 80 and allows each testing case to maintain its simplicity in operation 9 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL 3 BASIC COCO 80 OPERATION This section provides a detailed description of the CoCo 80 device including the user interface hardware CSA projects and peripherals CoCo 80 User Interface The CoCo 80 menu driven user interface is easy to use and requires little training Hard buttons on the front panel are used to initiate function specific menus The buttons
43. to select one of the templates to use you must selection one of the following Linear Spectrum Auto Spectrum or Frequency Response as the template in order to calculate the appropriate spectra The software will open the CSA Application Group associated with the template that you choose Linear Spectrum This application is the best choice for applying data conditioning to native time streams transforming time streams into block signals and applying data windowing and FFT calculations Auto Power Spectrum This application is the best choice for applying pply data conditioning to native time streams transforming time streams into block signals and applying data windowing and FFT to calculate auto spectra FRF Coh is also calculated in this application 110 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Frequency Response This application is best for applying data conditioning to native time streams transforming time streams into block signals then applying data windowing and FFT to calculate auto spectra cross spectra frequency response and coherence functions The software determines many factors based on the template selection Table 3 shows the availability of measurement quantities for the different templates of basic spectral analysis m Table 3 Comparison of measurement quantities for different spectral analysis templates CSA Template Time Time Acquisition FFT and Cross FRF Coh streams of str
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45. 2009 235 39 0 Signalst4 Cut 1 11 APS che APS ch3 APSIch 4 m Figure 45 View the file content per signal 43 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Once a signal file is opened the user can show it in text mode or plot mode this is for the purpose of simple preview To view the signals in the display plot trace please use the recall function To recall a signal press the F3 recall button Signalst4 Cut 11 I apestek APSKch2 APSIch3 APS ch4 The CoCo will allow the user to recall a signal into an existing trace or a new trace Recalling into existing trace will overplot this signal with the all existing ones with the same type Rec Stop Button The CoCo 80 combines two traditional instruments a data recorder and a signal analyzer into one hardware platform Due to the requirement of different use cases the user interface design is a bit unconventional Two hard buttons Rec Stop and Save are designed for storage two soft buttons Restart and Run Hold are designed for controlling the data processing flow For details please refer to later Chapter about saving data Save Button save The Save Button is used to save block signals to memory These include transient time signals and spectra signals which unlike time stream data are a snapshot of a single block of data at the time the Save button is pressed This can be used to capture averaged spectra or transi
46. 4 90 MB 35 716B File Name EE Time RECO744 ep id 2009 7 e 1303 Ge E P E E RECO0243 6 24 2009 S 2 50 MB RECO242 Sk EN 2009 2 51 MB RECOZ41 ie 13 15 MB RECOZ40 i 2 4 13 18 MB z 13 18 MB 67 75 MB d 29 13 MB RECO236 3 5 22 2009 10 21 13 123 44 KB m Figure 44 Record Files screen shows the names and other attributes of files stored on the CoCo 80 Delete gt Delete Newest allows you to delete the newest a few files including and after the file that is being highlighted from the flash memory For example if there are 4 files in order in the 42 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL list File4 File3 File2 and File1 where File4 the latest and File2 is being highlighted when Delete Newest is pressed File4 File3 and File2 will be removed Delete gt Delete All allows you to delete all files for the flash memory at once Copy to SD Cards allows the user copying the signals or recording files into the SD memory card Recalled Files allows the user viewing all the recalled signal files Recall is a useful operation to review the data files in a signal display trace View Files shows a summary of the data file The Text Plot soft button allows you to display a text view including type points sample rate and units or change to a low resolution of the time record Record Files General Information Version 1 File Mame SIGO064 User Admin Test Note Default Test Time Created 5 6
47. ANUAL CRYSTAL instruments COCO 80 USER S MANUAL CoCo 80 Operation for Spectral Analysis This section describes the operations of CoCo that are specifically related to the FFT spectral analysis For general operations of CoCo refer to previous Chapters of this manual Select a CSA Project To run a spectral analysis CSA press the Analysis button and select either the Linear and Power Spectra or the Frequency Response Application group then select one of the CSA spectral analysis projects C54 Application Group Data conditioning Transient Capture C nd Power Spectra BIR alc APSLCh Acoustic Analysis NOE Time Last Modified 3 23 2008 Min Required Ch Nbr 4 Max Sampling Rate 102 4 kHz Limit Test Publisher Crystal Rotating Machinery Analysis Soli FSA Scrink Version 3 0 EE I he C54 Script Version 3 0 Swept Sine Measurement GR EEN Calculate the auto power spectra Filter GP S For all channels m Figure 107 CoCo Select Analysis Function selection display Set Analysis Parameters for Spectral Analysis To set the parameters for spectral analysis press the Param Buiton in the signal display window select Analysis Parameters then set the parameters 116 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL AutoFowerSpec Parameter Setup ameter setting Parameter List Sample Rate E Input Channels EEN Acquisition Mode Schedule Setup Display Preferences
48. Acquisition Mode trigger BE Run Hold Signal Analysis Restart reset counter relative time average number re arm trigger Time capture or spectra m Figure 70 Illustration of the difference between Display Run Hold Time Stream Record Stop and Signal Save Save Save Block Signals Data can be saved by defining which signals to save and under what conditions Select Signal Snapshot Save Setup under the Param Button 77 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Sampling Rate fs Analysis Parameters IW Input Channels Output Channel Acquisition Mode Schedule Setup Display Preferences Time Stream Recording Setup m Figure 71 Signal snapshot save setup Choose which signals should be saved by using the Up and Down Arrows and the Enter Button to add a check next to the desired signals These signals will be saved during a measurement when you manually press the Save Button Signal Snapshot Save Setup Use the Up and Down arrows to navigate then press the Enter button to select or deselect signals BLOCK ch2 Captured block signal D BLOCK ch3 Captured block signal BLOCK ch4 Captured block signal APS ch1 Signal analysis APS APS ch2 Signal analysis APS APS ch3 Signal analysis APS APS ch4 Signal analysis APS Also enable timer as 3 Seconds Me Always enable a timer When Save button is pressed the timer will be activated To deactivate it press the S
49. Averaging is also called RMS Averaging RMS averaging computes the weighted mean of the sum of the squared magnitudes FFT times its complex conjugate The weighting is either linear or exponential RMS averaging reduces fluctuations in the data but does not reduce the actual noise floor With a sufficient number of averages a very good approximation of the actual random noise floor can be displayed Since RMS averaging involves magnitudes only displaying the real or imaginary part or phase of an RMS average has no meaning and the power spectrum average has no phase information Table 2 gives a summary of the averaging methods described above m Table 2 Summary of Averaging Methods No statistical spectral Statistical spectral estimate for estimate for deterministic signals with random characteristics signals only Improve SNR Does not improve SNR Requires a synchronized Does not require a synchronized trigger in fixed relation to the trigger signals In CoCo 80 the user can select Linear Exponential and Peak Hold for power spectral averaging and select Time Linear or Time Exponential for time domain averaging Signal must have periodic Applicable to both pure random and components mixed random periodic signals Spectrum Estimation Error You may wonder how much confidence we should have when we take the spectral measurement This is an academic topic that can go very deep First you must classify your signal types If you
50. CRYSTAL instruments COCO 80 USER S MANUAL CoCo 80 Basic DSA User s Manual Version 1 3 Crystal Instruments Corporation 4699 Old Ironsides Drive Suite 100 Santa Clara CA 95054 USA COCO 80 USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL This page is left blank intentionally i COCO 80 USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Table of Contents ls INTRODUCTION MEN 1 GI JE 511 of eeh 3 Limited Warranty amp Limitation of Liability rrnrrrrnnrrrnnnrrrrnnvrrrnnvrrnnnvrrnnnvrnnnnvrnnnnvernnnvennnnnennnnnesnnnnennnnnennnnnennnnnennnn 4 Safety Information Read Eet 5 AG Adapter Voltage Range EE 6 Maximum Measurement Input Voltage cccccccssssccssssecessseeeessseeeesssneeeeseneeessseeeeeesueeesseeeeesssaeeeseseneeeessaeeeeseaes 6 If Safety Features are Impaired EE 6 2 QUICK STAR EE 7 Recording Time Streams with CoCo 80 srrrrnnvrrrnnvennnvvrnnnvvennnvvennnvvrnnnvnrnnnvnrnnnnnsnnnnnsnnnvesnnnvesnnnnesnnnnennnnnensnnnennnnne 7 Install Engineering Data management EDM software job 7 Downoad Data to un TE 8 Important Notice about the Concept of CA 8 3 BASIC COCO 80 OPERATION EE 10 CoCo 80 User Interface on cose deen censelecnaesteeseenestecnanyidtatonndiientecnsdadianestsaeanti enaenck e lt saned ec oueedice receiv te dane oanoseidusdaneseereneiducis 10 TINN 10 STE M 12 Monu E delen EN E E 12 Eeer 12 FE NN 13 MV PI 13 ET PIN 13 7 211 1011 0 E 13 See BU
51. Cable 11 AC DC Power Adapter 12 Power Cable to AC Outlet 49 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL m Figure 50 CoCo 80 peripheral connections Ethernet CoCo is equipped with an RJ 45 100 BaseT Ethernet jack to connect to a local area network or directly to a PC A cross over Ethernet cable must be used to connect the CoCo 80 to a PC directly If CoCo is connected to a network hub router or a switch then a regular Ethernet cable not a crossover cable should be used m Figure 51 Ethernet connection USB Ports The CoCo 80 has two USB ports one USB client mini USB and one USB host type A They are fully compliant with USB 2 0 full speed specification and backward compatible with USB 1 1 The shapes of two ports are different as shown below 50 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL m Figure 52 CoCo 80 has two USB ports client for PC connection and host for peripheral connection The USB client port is used to establish communication between the CoCo 80 and a PC When the USB client port is used CoCo 80 device acts as a slave unit The USB host port is used to establish communication between the CoCo 80 and other USB based peripherals such as a USB mouse or a USB memory stick In this case the CoCo 80 acts as a USB master device Mouse Support USB Mouse is supported with following operations F1 F6 function b
52. Data Processing Flow of CoCo CoCo 80 combines two instruments a data recorder and a signal analyzer into one system It is important to understand the differences between these two functions The following sections provide details of each The data conditioning and recording phase includes processing the data from native acquisition channels and data conditioning Data conditioning operations include filtering integration differentiation calibration and other math operations that can be applied to the continuous time streams All the signals in the data conditioning and recording stage are continuous time streams with a fixed sampling rate and do not include any gaps Time streams can be displayed or recorded The signal analyzer phase includes Acquisition Mode and CSA based block by block processing The acquisition mode controls how the continuous time streams are captured in fixed block size records The processing phase applies algorithms such as spectral analysis to the block by block signals Figure 65 shows how the input data is processed in the data conditioning and signal analyzer phases 66 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Rec St SESCH Signal Analyzer Phase FFT mene Transient Capture Octave MERO Analysis Run Up Run Down Data Conditioning and Testing Balancing Recording Phase Figure 65 Data Process Flow Diagram The system has two dedicated button
53. E 38 FIGURE 37 DIGIT NOTATION SETTING Sonsierra ranra E RN 38 FIGURE 38 THEME SETTINGS BLACK OR WHITE STYLE veisssssanscivsaingercuannpsvonainananeacagtansntsquanancidmnauevaateensquavasesantiunnetteiauns 39 FIGURE 39 SETUP MEASUREMENT SCREEN SHOWS THE INPUT OUTPUT DISPLAY AND ACQUISITION MODE RT ET 39 REN SSE GAELS MON SCREEN cconctunevcnanenneaysdanstasnctot ona dessranctans ane TERA hort E tanga R opal a oneronetnan ee 40 FIGURE AI CALIBRA BION REPOR Lupen 40 FIGURE 42 DISPLAY PREFERENCE SCREEN E 41 OUREA Ek AE Ee 42 FIGURE 44 RECORD FILES SCREEN SHOWS THE NAMES AND OTHER ATTRIBUTES OF FILES STORED ON THE COCO gege 42 FIGURE 45 VIEW THE FILE CONTENT PER SIGNAL TTT 43 vi COCO 80 USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Mm FIGURE 46 TWO LEDS SHOWING POWER AND RECHARGE SIATUS 45 M FIGURE 47 RESET PIN HOLE CAN BE USED TO SHUTDOWN THE COCO 80 sersvrrnnervnnvrvnnvvnnnnvnnuvvnnuvennuvnnnnvnnunsnnnvnnnusennneen 45 Mm FIGURE 48 BNC INPUT CONNECTORS OUTPUT AND GROUND CONNECTOR ccc ccessssccecccseeessceescceseeesceseseeseees 46 FIGURE 49 COCO 80 PERIPHERALS AND ACCESSORIES wccncicsiscceicscncveiesicncssnnuicncakwacncasbousnsuntieadwenauensnsseuesionsssiinscaraceniceaaurnceds 49 FIGURE 50 COCO 80 PERIPHERAL CONNECTION S visessscsccivecescesncceene cece entevacosnvavacaeasabcesievadedancabaenbausvesebavsbandbavsteinavtseennbeds 50 FIGURE EE ETHERNET CONNECTION bien 50 M FIGURE 52 COCO 80 HAS TWO USB PORTS CLIE
54. IO ee ee ek NE 13 SOL Go g gt EEE E EE 14 Text and Number kKevpad Au 14 Welcome SEN eee 15 ee sed EN EN NN 16 DEE PI Aasen 18 Set a Window with TWO Traces ccccscccssssecssssecssseecssseesssesesseeecseeeeesasecesseecsseeeesseeeessaeessceeesssseessensessensesssneeesaes 21 SCUD 6 10 E 35 Sen 42 Bretelle BONON E 44 SET te EE eo dedoxesclsceace E e N E E E 44 CoCo 80 Startup and Shutdown rennnvvrnnnvvrnnnvvrnnnvrrnnnvernnnvrrnnnnrrnnnnesnnnnernnnnesnnnnennnnnesnnnnesnnnnennnnnesnnnnennnnnensnnnennnnnesnnn 44 Power on nd off 16 GOCO sssri REEN EE EAE EEA Ea AEE NEE Ni 45 STE E 116 EEE EE 45 Reset the system by Pushing the Reset Hm 45 Reset the system using the Power Button 45 CoCo 80 Software Disaster Recovery through EDM 46 Saisie beet 46 2006 80 INDU COMMECIONS Zeetesfeegeie see gegeegg eieiei eege degt a ana i a ian ea iaaiiai 46 SEN lee e veie 46 BLOG D 10 gE E 46 Kelsen ue 47 OL IMM UU EE 47 MEN 47 EPE ICP E 47 ii COCO 80 USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL CoCo 80 Output CONNECTIONS ccccccsscccssseeessseesssseeesseecesseecssseeceseeeceseeecesaeecsensesscseesseaeecsensesscesesesneesssneeessasessseeeeas 48 CoCo 80 Peripherals and Accessories rrnrrrnnnrrrnnnvvrnnnvernnnvrrnnnnnrnnnnnrnnnnnrnnnnernnnnnrnnnnnrnn renn nnrnnnnnennnnnennnnnensnnnennnnnennn 48 Eee 50 VEPS en 50 Mouse SUP une 51 BK re 1151 E at en ee ee en a E E E I EA 51 Ate e RRE 52 Su EE ER 52 P
55. N eege 53 DC DC Converter for Car Cgarette 53 CoCo 80 On Line Updates ue 53 Advanced Audio Be ee 55 Hardware Audio Pepberale Ae 56 Ae e E ie EE 57 Headphone Listening e 58 Record VOICE luede EE 58 Playback the Voice Annotations ON Coto 59 Playback the recorded signals from output channel 60 CSA Configurable Signal Analysis 0nnna0nnannnnannnenenanennaonnannnnnnnnsnnnnnrnasrrnnnnnnnrnnnrnnnnrnnsennnnnnnnrnnsnnnnneenneennnennnn 61 Preprogrammed CSA ege 63 Change CSA projects from the Co o 20 65 Editing CSA from the RE d ET 65 The Analog Signal Conditioning and Data Pre Conditioning rvrnrnnvvernnnvvvrnnnnvvrrnnnvvrnrnnvverrnnnvnrnrnnnnernnnnnennnnnnnenennn 65 The Data Processing Flow Of CGoto 66 PAC QUIS lee KE 68 ACero B C ue gt EE EE NE ES ee ee 68 TEMME essene E ne ee een nee eee 69 Tagger Ted 69 TIAGO d DE E MN NN NE 70 OG e EEN 71 ACQUISITION Mode Setup ccccscccssseecssseecssseecsseeeseeeessseeecsseecesseecesseecsseeececaeecscesesecseesscaeeeseneessensesseasesssneasesseeess 71 Using a Trigger during Meaeurement 73 ET EN da Mr e Te EN 74 Save Data to flash Memory or SD memory Card 76 MON 76 Save Long Time Waveform Goals 76 SAVE BOK SOAS net 77 PN 78 Using Schedule to Save at 79 Re UR EE E EE E EE 81 4 BASICS OF DYNAMIC SIGNAL ANA vol rrrnrvrnnrvrnnvvrnnvvrnnvvrnnvvrnnvrrnnvrrnnvrrnnvrsnnvernnnrsnnvennnvnsnnvennnnessnnrnnnnennnnenn 85 General Theory of Spectral Analysis Ae 85 FT TS Te
56. NT FOR PC CONNECTION AND HOST FOR PERIPHERAL ENE NNN 51 E PIGURE SS COCO BAI TER EE 53 M FIGURE 54 NETWORK CONNECTION FOR COCO SOUDDATE 54 M FIGURE 55 ON LINE UPDATE DETECTION STATUS SCREEN cccccsecccseccsscccsseccnscccscccascccccccnsccansecassceacecenscceseceaeeees 55 E FIGURE 56 BUILT IN SPEAICER EE 56 M FIGURE 57 AN EXAMPLE OF HEADPHONE 1 ccccccsecccsscccsccccscccnscccnscccnsccaseccuscccnsccessecassecacccenseceusceuseceseceusecasseeaeeees 56 PIG BS CONE enk TEEN 57 M FIGURE 59 MICROPHONE WITH PUSH BUTTON PART COCO A12 ervernnvvnnnnnvvnnnnnvnnnnnvvnnnnnvvnsnnnvnesnnvvnnsnnvnnssnnvnnsnnvnnnnnnne 57 E FIGURE GO AUDIO SETTING PAGE ua Gen aennn 57 M FIGURE 61 SELECT THE CHANNEL FOR HEADPHONE LISTENING i eerevernervenevrvnvvrnnvvnnvvvnnvvnnnuvnnnnvnnnnvnnuvsnnuvnnnnvnnunsnnusvennusnnnneen 58 M FIGURE 62 MONITOR THE VOLUME OF THE MICRORHONEINPDUT 59 M FIGURE 63 PLAY BACK VOICE ANNOTATIONS FROM THE FILE WIEN 59 M FIGURE 64 PLAY ALL ANNOTATIONS USING NEXT AND PREVIOUS BUTTONS c ccecccsecccssccessccessccscccssccessceaeees 60 FIGURE 65 DATA PROCESS FLOW DIAGRAM riscici icles catia uacreredauateadinediseacnishatiensdvascieataiontioaneeiadeied i 67 Mm FIGURE 66 DATA PROCESSING IS SEPARATED INTO THREE STAGES cccccsecccsecccssccscccscccsscccssccassccseccsseceseeaesees 68 M FIGURE 67 PRE TRIGGER NEGATIVE DELAY EXAMPLE a 71 M FIGURE 68 WAITING FOR TRIGGER MESSAGE 74 M FIGURE 69
57. NUAL CRYSTAL instruments COCO 80 USER S MANUAL Step 2 compute the instantaneous cross power spectral density Syx Sx SyT Step 2 average the Mframes of Sxx to get averaged PSD Gxx Gyx Average Syx Step 3 Compute the energy correction and double the value for the single sided spectra Gyx 2 Gyx EnergyCorr Frequency Response and Coherence Function The cross power spectrum method is often used for estimating the frequency response function FRF between channel x and channel y The equation is Hy Gy Gy where Gyx is the averaged cross spectrum between the input channel x and output channel y Gxx is the averaged auto spectrum of the input Either power spectrum power spectral density or energy spectral density can be used to compute the FRF because of the linear relationship between input and output Using the cross power spectrum method instead of simply dividing the linear spectra between input and output to calculate the FRF will reduce the effect of the noise at the output measurement end as shown below input output gt System true Hyx tr NOISE estimated gt observed x Myx observed y m Figure 88 Frequency response function computation The frequency response function has a complex data format You can view it in real and imaginary or magnitude and phase display format The coherence function is defined as 2 ot Gy GG AA YY where Gyx is the averaged cross spectrum between the input
58. OCO 80 USER S MANUAL an IP address automatically If DHCP server is not installed on the local network fixed static IP address must be configured on the host PC Same subnet mask must be used If DHCP server is installed on the local network host PC can obtain an IP address automatically If DHCP server is not installed on the local network fixed static IP address must be configured on the host PC The same subnet mask must be used In this table DHCP dynamic host configuration protocol server refers to a piece of software installed on the local area network either wired or wireless that supports the Obtain an IP address automatically function on any networked device DHCP is commonly used in most office networks Transfer Data Files to the Host PC To transfer the recorded data files to a PC you must 1 Establish a physical network connection between the CoCo 80 and a PC This can be done by using either the Ethernet USB client port or SD wireless card 2 Execute the EDM software on the PC 3 Download the data files from the CoCo 80 to PC using EDM software The data files will be automatically stored in the ASAM ODS format They can be converted into other formats with the EDM software Configuring the CoCo 80 Network Settings CoCo 80 Network Settings must be configured when an Ethernet or SD Wireless card are used for communicating with the host When USB is used for the connection this section c
59. OGMAG SCAUNG ask 121 FOURE TIS OVER AP RATE SELECTION vvs 121 FIGURE 116 VIEW le RT 122 FIGURE 117 TRANSIENT CAPTURE OPERATION ON COCO vresconsccsncdccacsteeasanctvcaucentasoneeabesannusuetouaabinuavancdstauceevabecaoasebianeas 123 FIGURE 118 ILLUSTRATION OF A TYPICAL IMPACT TEST AND SIGNAL PROCESSING AANEREN 124 FIGURE 119 TYPICAL IMPACT TEST DATA TOP LEFT SHOWS EXCITATION FORCE IMPULSE TIME SIGNAL TOP RIGHT SHOWS RESPONSE ACCELERATION TIME SIGNAL AND BOTTOM SHOWS FRF SPECTRUM ce eeseeseesseeeeseeeeeseeeeeens 125 FIGURE 120 CSA EDITOR WIZARD TEMPLATE SELECTION ann 126 FIGURE 121 CSA EDITOR WIZARD ACQUISITION TRIGGER AND BLOCK ACQUISITION SETTINGS ane 127 FIGURE 122 ACO UIs MOI MODE SELECHON c ririosinontaianui nia i EE ea a i A 127 FIGURE 123 SELECT THE DATA WINDOW TYPE FOR TRANSIENT CAPTURE an 128 FIGURE 124 TRIGGER MODES FOR TRANSIENT eege 128 FIGURE 125 TRIGGER CONDITIONS AND LEVEL SETUP FOR TRANSIENT CAPTURE ann 129 FIGURE 126 OVERLAP RATE FOR TRANSIENT CAPTURE csistisiesscasasstcesassostanncvguuncsangadnnssiqacionninadionsapssanntnsetaansapadaneanacioent 129 FIGURE 127 WAITING FOR TRIGGER MESSAGE unni caqsteonnsatavasadenanstbuvunsenevasnworeasanesundanavatedesasenesesaeunanes 130 FIGURE 128 ACCEPT REJECT DISPLAY FOR TRANSIENT CAPTURE cscsssscsssssssesssssceseesesecsessesesseseceesaeseesesaeseseneaseess 130 FIGURE 129 WHEN AVERAGING IS COMPLETE YOU CAN RESTART A NEW TEST WITH THE RUN BUTTON 131 FIGURE 130
60. P Sch 112 5859455 Remove Cursor 1 Remove Cursor 2 WE Add Cursor Yi Add Cursor Y2 Remove All Cursors Peak Mark ke D atb WEN Cursor m Figure 29 Cursor setup The RMS values will be displayed in the same unit as Y label unit The RMS is estimated to the energy between two vertical cursors ER Deh APSichel 114 5236282 J2 6404953 Cursor Lekt m Figure 30 Multiple cursor display Run Hold Soft Button controls the display update and the signal analysis process When the device is in Run mode the display updates the traces with the signals as fast as possible When the device is in Hold mode the display stops updating Note that Run Hold is independent of Record Stop This means that when in Run mode signals are not recorded to memory until the Rec Stop button is pressed The record status is indicated by the red record icon blinking at the top of the screen during recording It is important for you to understand the difference between Run Hold and Record Stop so that operator errors are not made in recording signals When in Hold mode the signal analyzer will be held Processing such as spectral analysis will be frozen 34 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Setup Button The Setup Button changes the screen to the Main Setup screen There are two pages of Setup The first page is all about the measurement settings Pressing the System icon
61. R Trigger Source lt Low Level edge trigger High threshold level Low threshold level Trigger Delay Trigger delay allows a captured signal to include some data before or after the trigger event This is done by defining some number of points or the percentage of the total Block Size that the capture occurs after the trigger event For example if the Block Size is set to 1024 and the trigger delay is 10 the data capture will happen 102 points after the trigger event 70 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL A negative trigger delay is more common for transient data capture Negative trigger delay means that the data capture will include data points before the trigger event For example a 10 trigger delay means that the data capture will include 102 data points before the trigger event with Block Size 1024 Some instruments call a negative trigger delay a Pre Trigger The following picture shows the concept of a negative trigger delay Block Size 1024 7 AG High i threshold level Trigger delay 102 points 10 m Figure 67 Pre Trigger negative delay example Overlap When overlap is enabled then the data is averaged from data frames that are overlapping This reduces the averaging time Overlap is only used when the Acquisition Mode is set to Free Run or Continuous after Trigger Otherwise it is not used Continuous capture without further trigger can al
62. Recording Time in Seconds 4GB 6 100 8 1 2 4 1024 1024 1024 6 100 8 1 2 745654 sec 207 hours Display Preference is used to set up the preferences about signal display Notice that the spectrum type and horizontal axis either in linear or log is set up here Display Preferences VEE be Spectrum Type and Scaling l GUDA Analysis Parameters is used to change parameters that are defined in the CSA project These parameters depend on the definition of the CSA project but may include block size window type average mode average number excitation and response channel etc Refer to the CSA project description in Section 4 for more details Analysis Parameters setting is dependent on the selected CSA Different set of CSAs may show completely different Analysis Parameters 29 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL FRF 4 Parameter Setup Parameter List Item Description H Window Type Hanning p Average Mode Linear Average Number 64 m Figure 25 Analysis parameters setup screen Time Stream Recording Setup defines which time streams will be recorded to memory when the Rec Stop button is pressed To add a stream to the record list select if in the Signal List using the up and down buttons and press the Enter button Note that the more signal added to the Record List increases the file size of the recording and reduces the record time to flash memory Only streams that
63. Reset Pin You can reset the system by inserting a pin or paper clip through the reset hole The Reset pin hole is shown below m Figure 47 Reset pin hole can be used to shutdown the CoCo 80 Reset the system using the Power Button You can reset the system by pressing the power button for more than 4 seconds which will force the system to shut down After the system is shut down it can be rebooted by pressing the power button again 45 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL CoCo 80 Software Disaster Recovery through EDM In the case that the CoCo 80 application software programs are completely corrupted due to an unknown reason you can also use EDM the host software to restore the CoCo 80 back to its original state when CoCo 80 is connected to the host via USB Keypad Lock To avoid accidental mistaken operation to the keypad it can be locked by pressing the power button and then pressing the Lock the Keypad Soft Button To do this simply press the Power button and make the second selection CoCo 80 Input Connections This section describes the CoCo 80 input connections and the related circuit design including a description of single ended versus double ended AC versus DC coupling and IEPE m Figure 48 BNC input connectors output and ground connector System Calibration The CoCo 80 loads factory calibration data during start up eliminating the need for daily calibration ch
64. S 91 M FIGURE 83 A SINE WAVE IS MEASURED WITH EUPK SPECTRUM UNIT THE SINE WAVEFORM HAS A 1V AMPLITUDE EEE ENE EE 92 M FIGURE 84 A SINE WAVE IS MEASURED WITH EURMS SPECTRUM UNIT THE PEAK READING IS 0 707V THE SINE WAVEFORM HAS A 1V AMPUTUDE Guss edd 92 Mm FIGURE 85 A SINE WAVE IS MEASURED WITH EURMS 2 SPECTRUM UNIT THE PEAK READING IS 0 5V THE SINE WAVEFORM HAS A 1V AMPLITUDE 2 0 0 eee cece cecccecccscccscccsccsccsccsccssccsscesscesscasscasccascesccescenscesscesscesscaeseusecseenseenseees 93 M FIGURE 86 WHITE NOISE WITH 1 VOLT RMS AMPLITUDE AND VOLTS HZ PINT EE 93 M FIGURE 87 RANDOM SIGNAL WITH 1 VOLT RMS AMPLITUDE AND ENERGY SPECTRUM DENSITY FORMAT 94 M FIGURE 88 FREQUENCY RESPONSE FUNCTION COMPUTATION 95 M FIGURE 89 ILLUSTRATION OF A NON PERIODIC SIGNAL RESULTING FROM SAMPLING ccccsecccsecccsscccsecceeees 96 FIGURE 90 SINE SPECTRUM WITH NO LEAKAGE ssrevenevenevnnevrnevnnvnnvnnvvnnvvnnvennvnnnvnnnvnnnvnnuvnnuvnnuvnnnnnnvennnnnennnnvnnuvnnunnnunnnunnnee 97 vil COCO 80 USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL FIGURE 91 SINE SPECTRUM WITH SIGNIFICANT LEAKAGE musnnonornnrenerenvnnenevenennnvnnenevrnnsnnvnnennvvnnenvnrnnsnvnenensvrnnsnsnrnnsvuvenenenee 97 FIGURE 92 SINE SPECTRUM WITH FLATTOP WINDOWING FUNCTION nen 98 FIGURE 93 SPECTRAL SHAPE OF COMMON WINDOWING FUNCTIONS anne 100 FIGURE 94 WINDOW FREQUENCY RESPONSE SHOWING MAIN LOBE AND SIDE LOBES
65. SIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL CoCo 80 Output Connections The CoCo 80 includes one output channel that can act as a function generator and provides a variety of waveforms synchronized with the input channel sampling rate The output channel is a 0 3 mm stereo jack A stereo jack to BNC adaptor is provided with the unit For each waveform the parameters such as amplitude and frequency can be specified with the Output Parameters screen from the Display screen and the Param soft button The output waveforms include None Sine Triangle Square White Noise DC Chirp and Swept Sine CoCo 80 Peripherals and Accessories This section describes the peripherals and accessories available on the CoCo 80 including SD Card audio devices Ethernet USB audio and battery The CoCo 80 includes interfaces to many peripheral devices These can be connected to the hardware via the connectors shown below 48 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL 12 m Figure 49 CoCo 80 Peripherals and Accessories Item Description Description 1 CoCo 80 Handheld Data Acquisition System 2 Suitcase with foam inside 3 Hang Strap 4 USB cable 5 Regular Ethernet cable 6 BNC cable 7 CD for EDM the host software User s Manual in PDF 8 Cable for Output Signal Source 9 Main Battery installed 10 Cross Over Ethernet
66. USB cable e Connect CoCo 80 to a PC directly using Ethernet via cross over cable e Connect CoCo 80 to a local network using Ethernet where a host PC resides on the local network e Connect CoCo 80 to a local network using a wireless SD card The table below summarized the configuration for these connections m Table 4 PC to CoCo 80 Configuration Summary method Connect CoCo 80 No special configuration required Install the EDM host PC software to a PC directly Install the CoCo 80 USB RNDIS using USB Driver Connect CoCo 80 CoCo 80 must be configured with Host PC IP must be configured to a PC directly a fixed static IP with fixed static IP at the same using Ethernet via subnet mask as that of CoCo 80 cross over cable Connect CoCo 80 If DHCP server is installed on the If DHCP server is installed on the to a local network local network CoCo 80 can obtain local network host PC can obtain 141 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments using Ethernet where a host PC resides on the local network Connect CoCo 80 to a local network using wireless SD card an IP address automatically If DHCP server is not installed on the local network fixed static IP address must be configured on CoCo 80 If DHCP server is installed on the local network CoCo 80 can obtain an IP address automatically If DHCP server is not installed on the local network a fixed static IP address must be configured on CoCo 80 C
67. WAV File This is the sound wave files that can be played by most of the media players Due to limited information a wave file can carry the wave files exported only contain very basic waveform shape and it does not hold any attribute information of ODS You are expected to use the WAV file to listen to its sound effect instead of for data processing 150 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL APPENDIX Version 1 27 2010 Add playback function Change CI address Users Manual Typeface Headings Arial Black 12 and 11 pt Body Text Arial 10 pt Captions Arial Narrow 9 pt 151 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Declaration of Conformity Declaration of Conformity for CI CoCo 80 Handheld Data Acquisition System Manufacturer Crystal Instruments Corporation 4699 Old Ironsides Drive Suite 100 Santa Clara CA 95054 Statement of Conformity EC Declaration of Conformity Council Directive 2004 108 EC on Electromagnetic Compatibility WE Crystal Instruments 4699 Old Ironsides Drive Suite 100 Santa Clara CA 95054 USA Product Name CoCo 80 Handheld Data Acquisition System Model No CoCo 80 Assessment of compliance of the product with the requirement relating to Electromagnetic Compatibility Directive The product has been assessed by the application of the following standards EN 61326 1997 A1 1998 A2 2001 EN61000 3 2 2000 EN61000
68. a transient process This is why the exponential window may be chosen to reduce the leakage effect in its spectral analysis On the other hand the exponential window may artificially change the spectral shape so the estimated damping is biased Since most modern instruments allow can capture very long buffer of data it is preferred to increase the buffer length instead of applying the exponential window 108 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Damping factor and the resonant frequency can be calculated by using curve fit method that applies to the FRF signal Without curve fit the estimation of damping value can go off significantly especially in a light damping system In CoCo or EDM software the user can use dual cursors to calculate these values as show in the picture below Add Cursor 82 Remove All Cursors CSA Editor Operation for Spectral Analysis This section describes the operation of CSA Editor related to FFT based spectral analysis For general operation of CSA Editor refer to the CSA User s Manual CSA Editor Wizard This section summarizes how to create a CSA project for general spectral analysis in the CSA Editor We strongly recommend that you read the CSA Editor User s Manual to gain more detail information before proceeding with this chapter To start click on the CSA Editor icon in the upper right corner in EDM and start the CSA Editor The CSA Editor Wizard dialog
69. achine conditioning monitoring automotive aviation aerospace electronics and military that demand easy quick and accurate data recording and real time processing in the field CoCo 80 is a low cost light weight battery powered handheld system with unparalleled performance and accuracy The user interface of CoCo 80 is specifically designed for easy and simple operation while it maintains the capability of providing a wide variety of analysis functions The CoCo 80 hardware platform supports two different software working modes dynamic signal analyzer DSA and vibration data collector VDC Each working mode has its own user interface and operation navigation structure DSA working mode is designed for mechanical structure analysis testing and optimization or for electrical geophysics and a wide range of applications VDC is dedicated to route based machine vibration data collection and trending The user will select one of the working modes to execute This manual describes the DSA working mode of CoCo 80 m Figure 1 CoCo 80 Hardware CoCo 80 is the first battery powered handheld data acquisition system that matches the performance and functionality of higher end systems CoCo 80 is equipped with 4 or 8 input channels and can accurately measure and record both dynamic and static signals The mass flash memory can record 8 channels of streaming signals simultaneously up to 102 4 kHz An embedded signal source channel provides various si
70. an be ignored To configure the network settings for the CoCo 80 complete the following steps 1 Power on the CoCo 80 In the Welcome page move the focus to IP address and press ENTER 2 In the IP Settings window click Edit the IP settings to specify a static IP address and subnet mask Type in the IP address and Subnet mask You must specify a static IP address and use a crossover cable to directly connect the CoCo 80 to the host computer In this case both the Gateway and DNS server fields must be blank or set to zeroes If the 142 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL network uses a DHCP server and you are not directly connecting the CoCo 80 to the host computer with a crossover cable click the Obtain IP address via DHCP server option button 3 Click OK to apply the changes 143 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments Select Connections amp USB Client b Wireless Colo 80 Device Status Ethernet Connection IP Address 197 168 1 118 Metwork Status EDM DHCP Serwer Internet Connected CI Server Connected m Figure 136 Ethernet connection status p USB Client k Wireless n IP address can be automatically assigned to this computer obtain an IP address via DHCP G IP Address Subnet Mask Default Gateway m Figure 137 Specify a static IP address for the Ethernet connection 4 Setup e Select Connections b Ethernet b Wireless Coco
71. are divided into three areas The navigation buttons include the power shift tab enter and arrow buttons The function buttons include the Analysis Display Setup File Rec Stop and Save buttons The six soft buttons located directly below the display change function depending on the current mode selection Fi F2 F3 F4 F5 F6 LE ESC t Analysis JUL Pisetay WI Next Tre an 7 GE eet ng P i Ess Vg EEE 5 7 N Ce Setup File View Mode 4 ghi 5 jkl J NN6 mno JJ SS Jl SI Enter gt EE II A NIZ I NN Sensors Recall User D TF J pars k f A Ge PA shift e eV TT H m Rec Stop Save Trg On Off J Vi e N 0 eS A H m Figure 4 Button layout on the CoCo 80 front panel Summary of Buttons The following table gives a brief description of the function of the buttons on the CoCo 80 Button name Power on the system Power down the system Reset the system press it 4 seconds or longer 10 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL a SHIFT lt gt Move the focus up In display window scaling expand the vertical range Up arrow In display window scaling vertically move the display range up depending on SHIFT position Move the focus down GH In display window scaling reduce the vertical range Down arrow In display window scaling
72. are of interest should be recorded to conserve memory and maximize recording time Time Stream Recording Setup is dependent on the selected CSA Note that only signals that are identified as Record Candidates in the CSA file will be visible and can be recorded This feature is designed to simplify the CoCo 80 user interface and optimize the device computation resources Signal Snapshot Save Setup defines which signals will be recorded to memory when the Save button is pressed To add a signal to the record list select if in the Signal List using the up and down buttons and press the Enter button Signal Snapshot Save Setup is dependent on the selected CSA Note that only signals that are identified as Save Candidates in the CSA file will be visible and can be saved This feature is designed to simplify the CoCo 80 user interface and optimize the device computation resources Signal Snapshot Save Setup defines the actions to be taken when testing limit exceeded Notice that this menu item will only be shown when the CSA project contains limiting check Usually you won t see this menu entry 30 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Parameter Setting Limit Alarm Actions Sample Rate The table shows actions can be carried out immediately when Input Channels Output Channel Acquisition Mode Schedule Setup Beep Sound One Display Preferences ave Signals Analysis Parameters Send Message to EDM Time S
73. ased Multiple annotations can be recorded during a measurement If this item is not checked the microphone button will not activate any voice recording Use headphone to listen to any input channel Enable the external headphone listening function Headphone Listening When Use headphone to listen to any input channel is enabled under the F3 Control Button of the signal display screen you will see the Headphone Playing menu item Select one of the input channels If you do not want to listen to the input channels then set the selection to System Sound or Recorded Annotations Restart Headphone Output Playing System Sound or Recorded Annotations P Channel 2 Channel 3 m Figure 61 Select the Channel for Headphone Listening Record Voice Annotations After Use microphone to record the voice annotation is checked in the audio setup connect the external microphone Part CoCo A12 to the microphone jack Press the Rec Stop button to record the time signals While the time signals are being recorded you can press the microphone button to record your voice annotation The voice annotations will be attached to the recorded time streams The green bar on the right bottom corner on the screen indicates the volume of the signal received by the microphone 58 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL ch F a sl m Figure 62 Monitor the volume of the microphone i
74. ation and operation please refer to EDM User s Manual The Engineering Data Management EDM is a PC software used for data management post signal processing viewing report and the connection between the Crystal Instruments hardware the PC and the data storage system EDM provides connectivity to one or more CoCo or Spider devices It provides data management tools that allow you to search through many tests records and view file properties or waveform characteristics The analysis tools allow you to display data in a wide variety of formats and configurations and let you identify important signal characteristics using cursors The report tool allows you to document the hardware configuration or data analysis results in a user formatted document The basic structure of EDM software is EDM CoCo DSA Mode with or without CSA Editor CoCo VDC Mode _ VDC Personal Spider Real Time Mode VDC Enterprise Ko EDM has four working modes 137 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL CoCo 80 DSA mode accesses CoCo 80 in its DSA mode download files and view data files CSA Editor a tool of editing CoCo testing projects will be included in this mode CoCo 80 VDC mode creates route data collection database upload settings to CoCo download data to PC trending and alarm analysis There are two versions of VDC mo
75. ave button for more than 3 seconds Select All Figure 72 Signal snapshot save setup In addition these signals can be automatically saved by placing a check next to Also enable a timer and specifying the number of seconds between automatic saves The signals can be saved with no delay between blocks by selecting Save Signals Continuously This option can be used to view all data blocks on a waterfall plot Save Points Save Points function saves a data point per signal at one time This function is particularly useful in the very long period monitoring applications For example people can save and monitor the vibration or acoustic level over a few months by looking at the data points saved every hour 78 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL All data points in one test will be saved into one data file The user can easily open view and analyze the data files using EDM PC software To set up the Save Points first go to Param gt Signal Save Predefined List screen then press F4 the Save Point Setup button a tab display will be shown The user can select one of following items for any time signal to save Current Value Max Min Peak Average RMS Or the user can select one of following items for spectrum signals to save Peak RMS Frequency of Peak Or the user can select one of following items for Sound Level Meter measurement to save Leq Lmax Using Schedule to Save Data An aut
76. be described first and in the most detail The other types will be explained briefly afterwards 73 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Manual Arm Trigger When the Acquisition mode is setup then a small popup window is displayed as shown in Figure 68 indicating that the system is waiting for a trigger event No signals are displayed until a trigger event is detected m Figure 68 Waiting for trigger message You can change from the waiting for trigger mode to Hold mode by pressing the F6 Hold button The window will close and the system will change to Hold mode Press Restart F3 or Run F6 to reopen the window and return to the waiting for trigger mode When a trigger event occurs due to the Trigger Source signal meeting the trigger condition the popup window will show a block of capture of data from the trigger source signal 74 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL m Figure 69 Trigger window with Accept or Reject options The display will depend on the type of signals in the pane 1 Ifatime stream is displayed then the display will update continuously You will not notice the difference before or after trigger event for the time stream 2 If ablock signal is displayed the block signal s in the background window will be updated with the new content 3 If a block signal in the frequency domain is displayed it will not be updated beca
77. bly due to the limitation of space people put it as EU Hz m Figure 86 White noise with 1 volt RMS amplitude and volts Hz PDS units Figure 86 shows a white noise signal with 1V ms amplitude or 1V in power level The bandwidth of the signal is approximately 10000 Hz and the V Hz reading of the signal is around 0 0001 VHS The 1 V RMS can be calculated as follows 1 Vims sqrt 10000Hz 0 0001 V Hz EU S Hz Energy Spectrum Density The EU S Hz displays the signal in engineering units squared divided by the equivalent filter bandwidth multiplied by the time duration of signal This spectrum type provides energy normalized to a 1Hz bandwidth or energy spectral density ESD It is useful for any signals when the purpose is to measure the total energy in the data frame Figure 87 shows a random signal with a 1 volt RMS level in the ESD format 93 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL 00 ES 0006 A amp Ae Ce 00 S 5 000 0006 a 0 000 4 0 000 5000 000 10000 000 Frequency Hz m Figure 87 Random signal with 1 volt RMS amplitude and Energy Spectrum Density format The ESD is calculated as follows Values for ESD values of PSD Time Factor were the Time Factor Block size Af and Af is the sampling rate block size Notice that in EU Hz or EU enz EU really means the RMS unit of the EU i e EUms It should also be noted that since a window Is applied in time
78. box will be displayed 109 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL 1 Please select the number of channels of the CoCo 80 that this CSA script will support and enable the software options for generating CSA 4input channels Coleg 9 input channels CoCo 18 input channels CoCo 90 Description Enable Realtime digital filter including decimation filter IIR filter FIR filter c Octave Analysis 14 13 146 and 1112 octave filters and sound level meters Order Tracking Order tracking in rotating machine analysis Swept Sine Frequency response analysis with swept sine source Limiting Test Apply upper or low limits to any block signals and trigger certain ev Histogram Histogram probability analysis and display for any time streams SESE SE SSS Tacho Phase and Orbit View relative phase and amplitudes of any analog channels vs ta Next Canca m Figure 99 CSA Editor Wizard Software Option selection Although it does not show up in the software option list the FFT based spectral analysis is a the heart of the software and is always installed and enabled in the CSA Editor by default This is true regardless of whether any other software options are enabled in the display 2 Select the application template Data Conditioning Only Transient Capture Linear Spectrum Auto Power Spectrum Frequency Response m Figure 100 CSA Editor Wizard template selection When you are asked
79. ch as Add Subtract Multiply Divide Square Square Root RMS Scale Offset Decimate e Parameters used by the signal analyzer functions such as FFT Auto Power Spec Coherence FRF e Time Stream Data Recording Settings e Block Data Save Settings e Trace Settings The CSA is designed to control how the data is processed not how the data is acquired When the CSA is changed the processing functions are changed according to the new CSA but the data acquisition parameters do not change For this reason the following settings have global effect and are not part of CSA project e Sampling Rate e Input Channels sensitivity coupling channel labels e Output Channel output waveform settings All pre programmed CSA projects have predefined parameters that are loaded when the project is selected You can modify the parameters on the CoCo 80 from the Param Soft Button in the Display screen Modified CSA projects can be saved with a different name using the Save As soft Button in the Analysis screen so that the original projects are not overwritten Most pre programmed CSA projects carry a variable called Maximum Sampling Rate This is the sampling rate that this CSA can safely execute without exceeding its computational resource limit Maximum Sampling Rate is used to limit the selection of the sampling rates 62 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Preprogrammed CSA projects The CoCo 80 is prepro
80. ct it The parameters can by applied to all channels using the soft button Apply to all Ch Physical Quantity defines the quantity such as acceleration velocity displacement force voltage etc Units defines the engineering units such as m s2 cm s2 gn etc for the input channel Sensitivity defines the sensitivity in millivolts engineering unit defined in the unit menu This selection opens a numeric keypad to enter the sensitivity value Press the OK soft button to accept the value When the Physical Quantity is selected as Acceleration you have the choice to apply a built in integration or double integration to generate readings in velocity or displacement When the Physical Quantity is selected as Velocity you have the choice to apply integration to displacement Notice that the algorithms for integration are implemented in the digital domain They also included a high pass filter and DC removal routines s F1 to edit the sensor and channel information 24 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL The instrument can automatically detect the status of IEPE sensor connection If the IEPE type of sensor was not connected correctly the input channel status will tell In the picture above channel 1 2 and 3 are enabled with IEPE input mode in software channel 4 is not Since channel 1 and 2 are connected with the IEPE sensors green letters IEPE are shown Channel 3 is not connected to an
81. ctions we will discuss how to choose different data windows Data Window Formula In this section we will describe the math formula that we used for each data window Uniform window rectangular w k 1 0 Uniform is the same as no window function Hamming window 21k w k 0 53836 0 46164 SL 7 e D Hann window 21k N 1 w k 0 5 0 5 cos The Hann and Hamming windows are in the family known as raised cosine windows are respectively named after Julius von Hann and Richard Hamming The term Hanning window is sometimes used to refer to the Hann window but is ambiguous as it is easily confused with Hamming window Blackman window 98 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL fork 0 N 1 k 0 84 0 5 ada 0 08 w k 0 5 COST 08 cos 7 Flattop window k 1 1 93 ai 1 29 de 0 388 eee w k 93 cos 29 cos 0 cosa fork 0 N 1 0 032 cos Kaiser Bessel window k 1 0 1 24 TE oaa WwW I ET 1 r KO 67k 0 00305 OS fork 0 N 1 Exponential Window The shape of the exponential window is that of a decaying exponential The following equation defines the exponential window k Ini final uer E fork 0 N 1 where N is the length of the window w k is the window value and final is the final value of the whole sequence The initial value of the window is one and gradually decays towa
82. d response y COH y x the coherence function of the excitation x and response y 112 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL FRF y x the FRF of excitation x and response y APS x the auto power spectrum of time stream x Data Conditioning Acquisition Mode Signal Anak Signal Summary i Frequency Response signals settings Enable all Display Candidate Enable all Save Candidate Enable for all FRF Transient Capture Output Display Candidate Save Candidate Function ExciResp ki Ocktent E Vi Fil Exci 2 BLOCK ch2 MI 7j v Resp 3 BLOCK ch3 Fi Fj dl Resp 4 BLOCK ch4 EA Fl Fl Resp 2 Analysis output signals settings Enable all Display Candidate Enable all save candidate Enable limit binding Display Candidate Save Candidate APS ch1 CPS ch2 ch1 Hich2 ch1 COH ch2 ch1 APS ch1 m Figure 103 CSA Editor Wizard Signal Analysis signal selection In this setting the signals set as Display Candidates will be selectable for display on CoCo only the signals that are set as Save Candidates will be selectable for Save on CoCo You should only enable the minimum necessary signals that are required in order to conserve DSP resources and simplify the user interface Enabling too many signals will make the user interface more complicated to navigate than is necessary For FRF or cross power computation you must designate one channel as excitation channel Once
83. d scenario might consist of a signal with a random nature that is not necessarily periodic It does not have obvious periodicity therefore the frequency analysis could not determine the amplitude at certain frequencies However it is possible to measure the r m s level or power level or power density level over certain frequency bands for such random signals In this case you must select one of the spectrum types of EU ms Hz or EU ms Sqrt Hz which is called power spectral density or root mean squared density A third scenario might consist of a transient signal It is neither periodic nor stably random In this case must select a spectrum type as EU S Hz which is called energy spectrum In many applications the nature of the data cannot be easily classified Care must be taken to interpret the data when different spectrum types are used For example in the environmental vibration simulation a typical test uses multiple sine tones on top of random profile which is called Sine on Random In this type application you have to observe the random portion of the data in the spectrum with EU me Hz and the sine portion of the data with EA Figure 82 shows a general flow chart to choose one of the measurement techniques and spectrum types for linear or auto spectrum Classify the nature of data Periodic na
84. d using the function or soft buttons the CoCo 80 remembers the previous screens so that you can easily move back one at time by pressing the Back Forward button 13 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Soft Buttons The F1 F6 Soft Button functions change depending on which screen is currently shown Some soft buttons open new screens that include additional soft buttons To keep the structure clear in the following description the soft button hierarchy will be displayed showing the string of the previous soft buttons or menus in gray and the lowest soft button in black as follows Hard Button Name Screen Name Soft Button Name Screen Name Traces poran Retr Aro ouro rn GI EI ei Ce Ce Cee m Figure 7 Soft Buttons change function depending on the current screen Text and Number Keypad Several screens require you to enter text using the keypad When the text keypad is displayed use the arrow buttons to move the focus to a letter or number and press the Enter button to select the character When the text entry is complete press the OK soft button ae em ca ke ma Jo Je Ja fe fs je fu fv fe x fy Je i 2 Ja le ve 3 CO 8 CEO i th HJT abs D J Cr miput amp abs Mute flue K D Ehanr Si ee m Figure 8 Text and numbers can be entered in the input screen Text Soft Buttons Upper Lower toggles the font to upper or lower case font Clear delet
85. ded file and can be played back on the PC using the EDM software e CoCo can play back any recorded time streams using its output port The output port can drive another audio device such as headphones or external speakers 55 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL These advanced audio functions require the following minimum hardware and software versions CoCo Software Version 2 1 7 8 Base Hardware System Version 22 0 9 Measurement Hardware Version 2 10 1 0 Firmware Version 2 1 5 0 Hardware Audio Peripherals Three hardware audio peripherals are used for the advanced audio functions 1 Internal Speaker 2 External Headphone 3 External Microphone The internal speaker is used to generate system related signals such as the sound simulating the key press power on off or alarm Voice annotations and measurement input audio can only be played back through headphones and not through the internal speaker vawr eg m Figure 56 Built in Speaker The external headphone jack uses the 3 5mm stereo jack connector You can connect any headphone to this connector m Figure 57 An example of headphone The headphone jack is located at the second to the left with a headphone symbol Voice annotations and measured input audio can be played back through the headphones 56 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL m Figure 58 Connectors The exter
86. des personal version allows the user access the database on his local PC Enterprise version allows multiple user access the database on the LAN r e o Fn Tags a tee ogregen D bat m ngt ve aioi tr o FRAN I8 at Raf huset WEE h UR 1146 N Se Zeg O ud a 10030 bf Aae O E AF Dy RONN 7 Oat ne E dy CRONE 1 13 et Antal amp WE E gt Da SEONG CECR Shat ae WEE ep ao 10 28 Stat duse NR 09 gt D ENE DE 48 Sat Aa E le CUCROREE 110849 rat erg WEE SE lan BETTE 120048 Shet daniel WEE OP Da SCHER 1942 48 Shat Ane WEE kremt men D VENN 19 48 1 af datet MOE a gt Dy UISTO 1940 7 Seit Aeg O WE E EE 118 Sirat Ania Em HA OAE 1 48 17 Sai ierg EE SE BEND 1 dn ie Daf Seng a E EE er dk Zeg WE pr Da EG 19 at 17 Dat Aug O EE D DER 1 DR et Zeg WE EP Da VET 193800 Bref Aia TER Da BAND 1 0 ff ane O EE er Ja EDEN 19 NEI tet daia WE AP Figure 135 EDM in VDC Mode Signal Analysis Display Cs 14 RTE ET ee E E EE EE ev av aro E EK u al e D Ze Lt E reg gt 3 lb bz ng ee gt BEE EE EE Bit ok aS ae kts a lt a s A dl ed e e Spider Real Time Mode operates on Spider hardware in real time 138 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL e Post Analysis Mode analyzes the data files on PC using various algorithms PA has three versions PA Viewer allows the user to view the
87. div 9000 GN 40 0 00 IN d Wi e sk i pr Hich2 chi 16 0 20 0 Ae AER 24 0 1500 00 Frequency Hz div Ni Math M d are E 1500 00 Freauencv Heldiv E h i Se e Add or remove window and chang Press Enter key to select or de selei Hichzchil A Frequency Fespa Frequency Respo Fregquency Respor Hich3 ch1 40 p ai 0 00 ek PL 2 16 0 2U U 24 0 0 00 1500 00 Frequency H2 div 9000 00 d un win t ne Nd Wi d sol fyr Hasj E 1500 00 Freauencv Haldiv A a d d ie t V Wi COCO 80 USER S MANUAL Highlight the Y Label area then press the Enter button CoCo will show Change Signals in Trace window Highlight the center plot display area then press the Enter button CoCo will stay in ZOOM mode for a few seconds Use four arrow buttons to scale the window Highlight the X label area then press the Enter button CoCo will stay in X scaling mode for a few seconds Use four arrow buttons to scale the X scale Highlight the Y display unit then press the Enter button CoCo will let you set the view mode Highlight the Y grid area then press the Enter button CoCo will stay in X scaling mode for a few seconds Use four arrow buttons to scale the Y scale Traces Soft Button opens the Trace and Window Setting Menu This menu lists the names of the existing windows in the display and is used to change the windows and signals in the display The m
88. e Domain Block Scroll or Auto scroll The block display option displays one block of data when the buffer is filled After a buffer is displayed the system will grab another buffer a fast as possible for the next block display Some portion of time signals between buffers will be ignored for display The scrolling display shows data scrolling continuously on the screen like a strip chart with no gaps in the scrolling display The auto scrolling option enables the system to choose the best display method for the user defined horizontal time interval Usually if the total time interval is less than 0 5sec it is displayed one block at a time as in block mode while a longer time interval will let the system display the signals with the scrolling method Horizontal Axis of Spectra specifies the format of the horizontal axis of spectra as either linear or log scale Spectrum Type and Scaling specifies the vertical scaling for spectrum traces The choices include EUrms EUpeak EUrms and EU Hz This selection only affects the auto power spectra or linear FFT spectra Acquisition Mode Soft Button specifies the trigger settings including free run continuous after trigger single shot without trigger single shot with trigger manual re arm trigger or automatic re arm Self Test Soft Button allows you to run a self test for the hardware without using external meter A built in precision signal source is used to check whether the input channels ar
89. e carried over by the files User Information shows the user name and address Date and Time indicates the date and time settings of the unit Connection indicates the network connection status of the unit The CSA project Menu at the top of the screen shows a list of the available CSA projects loaded on the CoCo 80 unit Use the left and right arrow buttons to select one and press the Run soft button to run the project 15 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Welcome Soft Buttons Setup changes to the Setup screen About shows the CoCo 80 system information including hardware version software version calibration status and software subscription period Update connects the CoCo 80 to the Cl server via an Internet connection and checks for new files and software updates You are then prompted to download the updates Test Note allows you to enter notes for the test All data files saved will be attached with Test Note Help is the Help document Run loads the CSA project and enters into the signal display window Analysis Button The Analysis Button changes the screen to the screen of Configurable Signal Analysis Application Groups SA AppiiCabhonGrop S Ga Ke LS C54 Application Group My CSA Gata conditioning Transient Capture Frequency Response Acoustic Analysis Rotating Ma chinery Analysis Swept Sine Measurement m Figure 10 CSA Application Groups T
90. e dynamic force signal is recorded by the DSA After the impact the device vibrations are measured with one or more accelerometers or other sensor and recorded by the DSA The DSA then computes the FRF by comparing the force excitation and the response acceleration signals Impact testing is depicted in Figure 118 123 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Modal Parameters Frequency Damping Mode Shape Figure 118 Illustration of a typical impact test and signal processing The following equipment is required to perform an impact test i An impact hammer to excite the structure With CoCo we recommend using an impact hammer with IEPE output which allows the hammer to be connected directly to the analyzer without extra signal conditioning One or multiple accelerometers that are fixed on the structure Again IEPE accelerometers can be used directly with CoCo without additional signal conditioning Coco Signal Analyzer The CoCo can be used to extract the resonance frequencies and damping factors of the structure In addition third party software can be used to extract modal shapes and animate the vibration modes A wide variety of structures and machines can be impact tested Of course different sized hammers are required to provide the appropriate impact force depending on the size of the structure small hammers for small structures large hammers for large structures Realistic signa
91. e filter shape Since time domain windows can be represented as a filter in the frequency domain the time domain windowing can be accomplished directly in the frequency domain In most DSA products rectangular Hann Flattop and several other data windows are used Rectangular Window w k 1 O lt K lt N 1 Hann Window w k 0 5 1 cos 22k N 1 O lt K lt N 1 Because creating data window attenuates a portion of the original data a certain amount of correction has to be made in order to get an un biased estimation of the spectra In linear spectral analysis an Amplitude Correction is applied in power spectral measurements an Energy Correction is applied See the sections below for details Linear Spectrum A linear spectrum is the Fourier transform of windowed time domain data The linear spectrum is useful for analyzing periodic signals You can extract the harmonic amplitude by reading the amplitude values at those harmonic frequencies An averaging technique is often used in the time domain when synchronized triggering is applied Or equivalently the averaging can be applied to the complex FFT spectra Because the averaging is taking place in the linear spectrum domain or equivalently in the time domain based on the principles of linear transform averaging make no sense unless a synchronized trigger is used Most DSA products use the following steps to compute a linear spectrum Step 1 First a window is applied X t
92. e fitting algorithm to estimate the damping factor The algorithm reduces the inaccuracy caused by the poor spectrum resolution or noise 5 Modal Frequency estimation The analyzer must provide capability of estimating the resonance frequencies CSA Editor Operation for Transient Capture This section describes the operation of the CSA Editor that is related to transient data capture and impact testing For general operation of the CSA Editor refer to the CSA User s Manual In the CSA Editor Wizard select one of the templates that contain the data transient capture capability Transient Capture is available in the following templates Transient Capture Linear Spectrum Auto Power Spectrum and Frequency Response 2 Select the application template Data Conditioning Only Transient Capture Linear Spectrum Auto Power Spectrum Frequency Response m Figure 120 CSA Editor Wizard template selection The Data Conditioning Only Octave Analysis Order Tracking and Swept Sine templates do not use regular transient capture to acquire the data After the Wizard is finished and data conditioning is applied as necessary go to Acquisition Mode to define the Trigger and Block Acquisition settings and the Acquisition Mode At least one input time stream must be selected as the Set as Trigger Source Candidate The items enabled as trigger source CAN BE SELECTED as trigger source when this CSA pr
93. e in the reasonable range If the circuitry of any channel is damaged or goes out of range the Self Test will tell Self Test does not change or replace the last time calibration results Testing Log record the most recent activities happens to the measurement A sample of testing log is show below 41 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL U aa i i Testing Log View This table logs all major testing events in sequence Total number of events is limited to 1024 Total Num 41 Event Time Ev ent Description Current Mumi 1 A 22 2000 ies Se C54 Chanqe LimitingTest 5 22 2 CSA ChangelFRF COH OPS APS 4 2008 11 T 12 ResetiChannel table reset 2 2008 11 40 42 Reset Channel table reset z a 1 us 38 30 Reseti Channel table reset Reset Channel table reset 2008 11 36 58 054 Change DefaultTime 41 36 19 Reset Channel table reset B m Figure 43 Test Log View Run VDC icon will allow you to switch to the vibration data collector mode If your CoCo is not installed with VDC mode this icon will not be effective File Button ar The File hard button displays the Storage Capacity status including capacity used space and free space Also the number of files is listed including CSA files and measurement data files Files displays a list of all the record files including the name created time test note and size Record Files 10 Files Total Size 14
94. e same dimension such as time or frequency Only the signals with the same engineering units in X and Y axis can be overlaid m Figure 14 Multiple traces can be defined and multiple signals can be displayed in each trace The traces are periodically updated when the Display is in Run mode To stop the trace updating press the Hold soft button Note that the trace updating display is independent of the Record operation This means that while traces are update on the display they are not recorded to memory until the Rec Stop button is pressed You should understand the difference between the trace update display and the record feature so that errors are not made in recording RMS 215 389u A trace typically consists of five objects The signal label on the left side displayed as APS ch1 in this example The center display area the area being highlighted The view mode displayed as dB V 42 RMS in this example The vertical Y scale range on the right Ch sl e The horizontal X Scale range on the bottom User can move around from one object to another Once one of the objects is highlighted pressing Enter button will guide to an operation to set the property of that object Below is a table describing the corresponding property when Enter button is applied to certain area on the screen Highlight Area After pressing Enter button 19 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments r ry d 0 00 1500 00 Frequency H2
95. eams for Mode Auto Power Spectra native each data Blocked Spectra channels conditioning Time output Capture Data Conditioning Only Capture Spectrum Spectrum Response The table illustrates that the Frequency Response template contains the most complete measurement quantity set If you want to measure time streams block time captures auto and cross spectra FRF and coherence all together select the Frequency Response template Does this mean that you should always select the Frequency Response template because it has all the measurements The answer is NO The more measurement quantities that are selected the more DSP resources that are required DSP resources refers to both real time computational capability and memory resources Sometime you have to make a tradeoff between speed size of the data buffer and the number of measurements taken As a rule of thumb always select the minimum function sets that you need to use It will save computational resource on DSP 111 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL a 16 kHz 62 5 us pt 20 45 kHz 48 528125 us pt 25 6 kHz 39 0625 us pt 32 kHz 31 25 us pt 40 96 kHz 24 4140625 us pt 51 2 kHz 19 53125 us pt 64 kHz 15 625 us pt m Figure 101 CSA Wizard Template sampling rate selection Next you must choose the Maximum Sampling Rate which is a number that controls the highest sampling rate that this CSA p
96. easure for the main lobe width is FFT bins or frequency lines The width of the main lobe of the window spectrum limits the frequency resolution of the windowed signal Therefore the ability to distinguish two closely spaced frequency components increases as the main lobe of the smoothing window narrows As the main lobe narrows and spectral resolution improves the window energy spreads into its side lobes increasing spectral leakage and decreasing amplitude accuracy A trade off occurs between amplitude accuracy and spectral resolution Side Lobes Side lobes occur on each side of the main lobe and approach zero at multiples of CN from the main lobe The side lobe characteristics of the smoothing window directly affect the extent to which adjacent frequency components leak into adjacent frequency bins The side lobe response of a strong sinusoidal signal can overpower the main lobe response of a nearby weak sinusoidal signal Maximum side lobe level and side lobe roll off rate characterize the side lobes of a smoothing window The maximum side lobe level is the largest side lobe level in decibels relative to the main lobe peak gain 101 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Guidelines of Choosing Data Windows lf a measurement can be made so that no leakage effect will occur then do not apply any window in the software select Uniform As discussed before this only occurs when the time capture is
97. easures the desired quantity For example an accelerometer should be used to measure acceleration a laser velocimeter pr velocity pickup should be used to measure velocity and an LVDT should be used to measure position However since position velocity and acceleration are related by the time derivatives it should be possible to measure an acceleration signal and then compute the velocity and position by mathematical integration Alternatively you can measure position and compute velocity and acceleration by differentiating The integration can be performed at the analog hardware level or at the digital level The CoCo provides a means to digitally integrate or double integrate the incoming signals The integration module fits into the very first stage after data is digitized as shown below Analog AID Optional Signal Tee High Pass Filter Conditioning and Integration Data Spectral rei Conditioning gt Analysis CoCo There are several issues to address in such implementation 1 The integration and double integration algorithm has to be accurate enough and it must find a way to reduce the effects of a DC offset A tiny initial value offset in the measurement or temperature drift before the integration may result in a huge value after single or double integration This DC effect can be removed using a high pass filter 2 The initial digital signal must have
98. eated in the same way as other time streams They can be analyzed or recorded CoCo also provides differentiation and double differentiation to calculate the acceleration or velocity from velocity or displacement transducers Differentiation is not as common as integration It must be noticed that the displacement after double integration to the acceleration is not the same as that measured by a proximity probe A proximity probe measures the relative displacement between an moving object to the fixed coordinates seated by the probe The accelerometer and its integration value can only measure the movement of the moving object against the gravity field Sensor Consideration Accelerometer signals that are non dynamic non vibratory static or quasi static in nature low acceleration of an automobile or flight path of a rocket are typically integrated in the digital domain downstream of the signal conditioner Piezoelectric and IEPE accelerometers are commonly used to measure dynamic acceleration and therefore dynamic velocity and displacement They should not be used to measure static or quasi static accelerations velocities or displacements because the IEPE includes analog high pass filtering in the sensor conditioning that cuts out any low frequency signal At frequencies approaching 0 Hz piezoelectric and IEPE accelerometers cannot with the accuracy required for integration represent the low frequency accelerations of a test article Whe
99. ecifically related to transient capture applications For a complete explanation of these settings refer to the Basic CoCo Operation section To run a Transient Capture CSA press the Analysis button and select a CSA Application Group that includes transient capture option These include Transient Capture Line and Power Spectrum and Frequency Response Then choose an Analysis Function from the CSA files on the CoCo to run Analysis Parameters Window Type First you must specify the Analysis Parameters under the Param Button Select the averaging mode averaging number and data window type Transient Capture commonly uses the Force Exponential or combination Force Exponential data window function Press the Apply button to accept the settings 127 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL SutoPowerSpect4 Parameter Setup Parameter List Item _pBlock Size 1024 Average Mode Exponential _p Average Number f Uniform K aiser Bes sel SI Bla ackman Fo FCE Exponential m Figure 123 Select the data window type for transient capture Acquisition Mode Next select Acquisition Mode under the Param Acquisition Mode controls how the data is acquired and under what conditions It includes setting the trigger mode trigger source level conditions and overlap Select Trigger Mode using the Mode Button Transient capture projects such as impact hammer tests typically use Manual Am Trigger
100. ecks Although the CoCo 80 does not require daily field calibration Cl recommends an annual calibration and performance verification by local Cl service centers To execute the System Calibration first press the Setup hard button then select System Calibration icon and press the Enter button DC Differential DC Differential allows measurement of signals with a non zero mean DC component and uses differential input mode Non zero mean signals are typically low frequency signals or signals that are measured relative to ground Differential mode is recommended when measuring signals with a common mode voltage CMV CMV is an in phase signal that appears simultaneously on both input terminals of an input channel Provided the sum of the signal and the CMV do not saturate 46 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL the input and cause clipping the measurement will be accurate If the signal and CMV exceed the input range then the signal will be clipped and produce erroneous results If the signal and CMV are very high and exceeds the maximum over voltage rating of the instrument front end then the data will be erroneous and the hardware can be damaged This must be avoided to protect the hardware from permanent damage DC Single End DC Single End allows measurement of signals with a non zero mean DC component and uses single ended input mode Single ended mode is recommended for most cases and when no CMV
101. edule or manually Save Block Signals The transient capture time signals frequency signals or other block signals can be saved automatically or manually Save Points The current value of the time streams or RMS of a spectrum or multiple statistics of signals can be saved automatically or manually in to one file over long period of time This is particularly useful in the monitoring applications The data can be saved either manually or automatically Save Long Time Waveform Signals The Rec Stop Button is used to control the streaming of time stream data to memory After a CSA project is selected pressing the Rec Stop button will start the display and also start recording the time stream to memory The red flashing Rec icon at the top of the screen indicates that the data is recording To stop the recording press the Rec Stop button again The red flashing Rec icon will not be displayed indicating that the recording has stopped Before a time stream can be recorded it must be defined in the Parameter Settings Time Steam Recording Setup If no time streams are defined in this setting when the Rec Stop button in pressed then a message will indicate that no signal are selected The Rec Stop button can also be pressed after the Run button is pressed The Run button starts the display of live signals but does not start recording After a recording is stopped the display will continue to display live signals until the Hold button is pressed
102. emains stored on the CoCo To un recall a signal take one of the following two actions UR A Ae AH E Record Files General Information Versjon I File Name SIG0205 User Admin Tes Note Default Test Time Created 8 9 2008 14 24 54 Sagnals 4 Cut iji APS ch2 m Figure 74 Recall signal pop up menu Method 1 In the above file menu press F4 to see all signals that can be un recalled You can either unrecall one signal or un recall all of them Method 2 Under the Traces menu select the last command Recalled Signal List Trace and Window Setting Select view Mode for Current Trace r Se coon PET H m Figure 75 Recall signals from the trace menu Recalled Signal List This table lists all recalled signals from recorded Files Total number of recalled signals is limited to 8 Recalled Signals Recorded Files m Figure 76 Un recall signal The recalled signals will have a signal name with a prefix of its file name The recalled signals can be displayed in the same way as live signals 82 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Add or remove window and change signals in a trace Press Enter key to select or de select signal in trace Wda Wine AP Stich aPSich2 Auto Spectrum AP Sich3 Auto Spectrum a T Aut o E D echt fi STGO091 APStchi Recalled Signal Auto Spectrum m Figure 77 Recalled signals appear with file name prefix The pictu
103. ent events at any time You can choose which signals are saved when you press the Save Button by selecting Signal Snapshot Save Setup under the Param Button When the CoCo 80 is connected to a PC the saved block signals can be downloaded using the EDM software CoCo 80 Startup and Shutdown This section describes power on and off lock the keypad and how to reset the CoCo 80 44 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Power on and off the CoCo 80 The power button is located at the lower left corner on the keypad The very first time the CoCo 80 is used it is necessary to set the clock time All the data acquired and stored will include the clock time as a file attribute with a clock time accuracy of seconds There are two LEDSs on the front panel The one on the left close to the power button is an indicator for the system on or off When the system is turned on it will be lit red The LED on the right is the indicator for external power charging When the CoCo 80 is being charged it will be lit in red When the system is fully charged and still connected to the external DC power it will be lit in green ODE D a Power Recharge m Figure 46 Two LEDs showing power and recharge status System Reset In the rare event of a system lock up the power on off button may not respond To restore the unit you can reset the system in one of two ways Reset the system by Pushing the
104. enu lists the defined windows at the top of the menu The display can be changed from one window to another by selecting a different window from the menu and 20 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL pressing the Enter button You can define any number of windows to provide a flexible display format L DES pm Ge HS MWindowl APS chl APS ch2 APS ch3 APS cht m Figure 15 Window and Trace Menu Traces Trace and Window Settings Menu opens the Trace and Window Setting screen This screen is used to add new windows and define which signals will be included in each trace After you select Trace and Window Setting and Add Window you can choose from a single 2D trace two 2D traces or one waterfall trace Add Window with two Traces Add Window with 3D waterfall trace After you select the window type you need to assign the signals to be displayed in this window To select a signal press the Enter button to check it Only signals that are defined in the CSA as display candidates will be visible and can be added to the trace This feature is designed to simplify the user interface and optimize the CoCo 80 computation resources If a signal is not available for display then the CSA must be edited before it can be added After the first signal is selected all the signals with different types to the first one will disappear from the list You can continue to select the rest
105. erages takes longer to compute Thus averaging will increase the time of the measurement To reduce the time a Moving Linear Averaging can be used Moving Linear Averaging uses overlapped input data points to generate more than 1 N results within a period of time Moving linear average has the advantage that the resulted trace update time can be much shorter than the linear averaging period N 1 HESE j 0 Where x k is the input data with sampling rate of T y n is the output data with Trace Update rate deltaT AverageT is the period of Linear Average and N is the total samples used for Linear Average N AverageT T Moving Linear Average is computed by SA yin The Moving Linear Averaging is illustrated in Figure 95 Assume the averaging period is AverageT but the progressive time for each averaging operation is deltaT the output buffer will have a data rage of deltaT instead of Average x k saved every T N AverageT deltaT AverageT N AverageT y n saved every delta m Figure 95 Illustration of moving linear average The Moving Linear Average is useful in many situations For example in Sound Level Meter Leq is defined as a linear averaged value over a long period of time say 1 second to 24 hours Assume the AverageT is 1 hour without moving linear average in a 24 hours period you can only get 24 readings This is not very useful With moving averaging you can get the readings in every 1
106. eraging is reset and the system runs in Free Run mode Single Shot with Trigger waits until a trigger event is detected After the trigger event the spectral analysis if there is any will reset its average back to 1 and waiting for the next trigger This mode is the best if you want to observe the time signal block by block at a certain trigger event Single Shot without Trigger waits until you press the Run button then acquires one block of data and returns to the wait condition This mode is the best if you simply want to observe a time signal block by block at an arbitrary time 68 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Auto Arm Trigger waits until a trigger event is detected then a block is acquired and the system returns to the wait condition If another trigger event is then detected the new block of data will be acquired This processes will continue indefinitely with no user interaction Averaging is reset after each trigger event This mode is the best for repetitive data capture and spectral analysis if you have confidence in the signal quality Caution should be used because a desired captured block of data can be replaced by a new undesired block of data if an addition trigger event occurs Use Manual Arm Trigger to ensure that the last block is not automatically replaced by a new triggered signal Manual Arm Trigger waits until a trigger event is detected then a block is acquired and the
107. ersal File Format BUFF rrrrnnnnnvennnnnvvnnnnnvvennnnrvernnnnvnrnnnnvnrnnnnnversnnnnnenennnnensnnnnernsnnnnenennn 148 De RT 149 MTP ebeeeEtEege 150 NTE 150 PR SJON 150 OSV Microsoft Excel IEN 150 WAV FIG EEE EE 150 APP ENDI nee en ne en ee E ee eee eee 151 VON 151 Users Manual Typeface Las eddespid 151 PETN C OnO E 152 v COCO 80 USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Table of Figures FIGURE 1 COCO 80 Even 1 FIGURE 2 CRYSTAL INSTRUMENTS COCO 80 SUPPORT WEBSITE reerennnasersennarsvsnnnnnenssnnnnnnessnnnansessnnnnesennnvnnssvenennnnvenennnnnee 4 FIGURE 3 CLIENT USB CONNECTOR FOR PC COMMUNICATION e 8 FIGURE 4 BUTTON LAYOUT ON THE COCO 80 FRONT PANEL urnnnnnnnnnnnvnnnnnnnnrnnnnnnnnrnnennnnnnnnennnnrnnnennnnrnnnnsnnnrnnnsnvnnnnnsnnnnnee 10 FIGURES COCO 80 DISPLAY STATUS E 12 FIGURE 6 STARTUP SCREEN IS SHOWN DURING STARTUP SEQUENCE uvvvnnvnvvnsnvvnsvnvnnsevnnsnnvnnsnvnnsnvrnssnvnnsnvnnsvvrnssvvnnsnvnnsnn 13 FIGURE 7 SOFT BUTTONS CHANGE FUNCTION DEPENDING ON THE CURRENT SCHREEN ann 14 FIGURE 8 TEXT AND NUMBERS CAN BE ENTERED IN THE INPUT SCREEN ann 14 FIGURE 9 WELCOME SCREEN IS SHOWN ON STAR UE E 15 FIGURE 10 CSA APPLICATION E EE 16 FIGURE HL ANALY SIs SCREEN IS USED TO SELECTA CSA iregi an a E AN 17 FIGURE 12 DISPLAY SCREEN SHOWS A WINDOW WITH ONE TRACE aan 18 FIGURE TWO ee 18 FIGURE 14 MULTIPLE TRACES CAN BE DEFINED AND MULTIPLE SIGNALS CAN BE DISPLAYED IN EACH TRACE 19
108. es all text from the text field Delete deletes the character to the left of the cursor Space adds a space Cancel closes the screen without changing the text 14 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL OK accepts the text and closes the screen Note It is more convenient to use one of 12 hard buttons to enter the number or letters For example Button Display can be used to enter number 2 or letter A B or C To make the selection pressing the button quickly will lead the selection to the next one Welcome Screen The Welcome Screen is shown after the system has completed the startup sequence It shows the available CSA projects at the top and other status at the bottom It can be used to verify the date and time network connection settings add a test note select a CSA project and run the project RMS 2 Conmpute RBS for 8 channels FRF S 4pply window FFT square and average calculation to 8 channels and generate 7 Freg Response function AutoPowerSpec S Apply window FFT square and average calculation to generate auto power spectrum For channels m Figure 9 Welcome screen is shown on startup Enter Test Note allows you to add text that will be appended to all data files as a file attribute This is can be used to add notes such as test conditions locations for later reference and can be used to search through data files by key words The text typed in the Test Note field will b
109. g startup sequence Power Down To power down the unit press the Power button and then press the Turn Off soft button The Cancel soft button returns to the previous menu without powering down the unit Lock keypad function can be selected instead of Power Off Arrow Buttons The arrow buttons are used to move the focus from one field to another on the display By moving the focus you can select deferent fields to enter parameters select other screens and enter text They are also used to zoom in and pan around a trace When cursors are enabled arrow buttons are used to move the cursor positions In the trigger setup window the arrow buttons can be used to move the threshold and trigger delay Enter Button The Enter Button is used to accept an entry or select an item on the display In general to select an item use the arrow buttons to move the focus to the item and then press the Enter button to select the item Shift Button The Shift Button serves multiple functions depending on the context In the signal display window the F4 soft button ZOOM in out or moves the display The Shift Button toggles between ZOOM and move ZOOM changes the size of the plot and move changes the position of the view In the Window setup if you set a two trace window the Shift button toggles between the top and bottom traces Escape Button The ESC Button is used to move back to previous screens or cancel the current action As the screens are change
110. gger The arrow buttons can also be used to set the trigger level and delay settings 72 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL p g Ope EM Mode Condition Manual Arm Trigger ch1 gt High Level Trig Src chi Low Level 1 0 High Level 796 0m AHC Auto Scale Window Fixed Scale Window OGGE Use the arrow buttons to change the trigger level and delay while the data stream from the trigger source Is displayed Press F4 to activate one of four functions for the navigation arrow buttons 1 Auto Scaling Window 2 Fixed Scale Window Arrow buttons used for expanding or reducing the scales 3 Moving window Arrow buttons used to shift the positions of the window 4 Arrow buttons are used to set the high threshold level low threshold level and trigger delay The method 3 is a more convenient way to set the trigger threshold level instead of using the editing tool under F3 The editing tool allows you to set the trigger level to a precise value Press F5 to set the overlap rate This factor will only have effect when the acquisition mode is set as Free Run or Continuous after Trigger After all trigger parameters are set press F6 OK button then the system will exit to the main measurement display window Using a Trigger during Measurement This section explains the trigger operation while making measurements Manual Arm Triggering is the most common mode and will
111. gh quality dynamic range signal to noise ratio cross channel gain match phase match and spectrum flatness over an analysis frequency range up to 45 kHz When it is used to measure the static or quasi static signals it offers very high accuracy at DC or near DC frequency The CoCo 80 utilizes a new signal processing method Configurable Signal Analysis CSA CSA provides unique flexibility for real time analysis including filtering and spectral analysis For DSA applications the CoCo 80 software stores and organizes the data in the popular ASAM ODS standard Data may be exchanged with other data formats such as UFF BUFF NI TDM ASCII MATLAB or Excel The ASAM ODS data standard provides ultimate flexibility and version compatibility ASAM ODS data standard is widely supported by the automotive industry and is expanding to aerospace and other areas For VDC applications the CoCo data is stored and managed by the database The handheld system is equipped with two USB ports 100 Basel Ethernet SD card interface audio input output 5 7 inch color LCD display and a keypad You can connect the CoCo 80 to a PC download files and upgrade the software through several means of network connection The user interface of CoCo 80 is specifically designed for easy and simple operation while it maintains the capability of providing a wide variety of analysis functions The CoCo 80 has a weight less than 1 7 kg Advanced thermal design eliminates the need f
112. gnal output waveforms that are synchronized with the input sampling rate CoCo 80 hardware uses dual CPU architecture An XScale CPU handles the user interface project configuration power management network communication as well as all the peripherals A 1 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL high speed floating point DSP manages the data input output and real time processing CoCo 80 is also configured with large RAM and NAND flash memory for mass data storage Special thermo and low power design eliminates the need for a cooling fan and increases the battery operating time Proprietary hardware technology delivers more than 130 dB dynamic range The extremely high dynamic range eliminates the need for multiple front end gain settings The CoCo 80 can also be operated from a DC power source which will also simultaneously charge the battery This can be achieved with either the CoCo 80 AC DC Adapter P N 40 115 or an Automotive Cigarette Lighter Adapter Revolutionary 24 bit A D converters digital technology and unique hardware designed for CoCo 80 offers more than 130 dB dynamic range 10 100 times higher than competitive products The high dynamic range and fidelity of the CoCo 80 enables measurement of a wide range of signals regardless of the input signal magnitude CoCo 80 excels in both dynamic and static measurements When used for dynamic measurements the inout channels offer extremely hi
113. grammed with a set of default CSA projects which provide a wide range of options that meet most users needs Additional CSA projects may be downloaded from the Crystal Instruments web site In addition by using CSA Editor the advanced users may edit or develop their own customized CSA projects to meet their specialized needs Typical default CSA projects are given below m Table 1 Preprogrammed CSA project Descriptions Yellow highlighted are most often used CSA Group CSAs used for 4 CSAs used for 8 channel Description channel CoCo 80 CoCo 80 Data RMS 4 csa RMS 8 csa Calculate the RMS of each input Conditioning channel Overlap ratio and average time are changeable PkPk 4 csa PKPK 8 csa Calculate the peak to peak value for each channel CS Subtract 4 csa Subtract 8 csa Channel 1 is subtracted from each other channel Multiply 4 csa Multiply 8 csa Multiply each channel by channel 1 Add 4 csa Add 8 csa Add channel 1 to other channels Integration 4 csa Integration 8 csa Digitally integrate each channel Suitable for signals with higher frequency content IntegrationLow 4 csa IntegrationLow 8 csa Digitally integrate each channel Suitable for signals with low frequency content OffsetScale 4 csa OffsetScale 8 csa Apply an offset and a multiplier to each channel The offset and multiplier can be modified in Analysis Parameters Transient Transient 4 csa Transient 8 csa Time streams from each channel Capture
114. h filter order 7 Acoustic Analysis Order Tracking 64 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Limit Test TimeLimiting 4 csa TimeLimiting 8 csa Apply limit test to the time stream TT In signal of each channel Limits are edited in GSA Editor APSLimiting 4 csa APSLimiting 8 csa Apply limit test to the auto power are edited in CSA Editor captured signals Limits are edited in CSA Editor analysis of each channel When a CSA project is running you can choose to display record or save data streams or signals Change CSA projects from the CoCo 80 A CSA project specifies the analysis settings and functions including analysis parameters and functions time stream recording block data save and trace settings After a CSA is selected it can be modified from the CoCo 80 to change these parameters using the Traces and Param soft buttons in the Display screen The modified CSA can then be saved using the Save As soft button in the Analysis screen This allows modified CSAs to be saved and used again later Editing CSA from the EDM Software CSA files can also be edited or new CSA files can be created from scratch from the EDM software onaPC This feature allows the advanced end user to create custom analysis functions to suit their special needs This advanced topic is not covered in this manual Refer to the Cl Support web page for documentation about editing CSA from the EDM software T
115. hat identifies the binary format the size of the binary record the format of the binary structure etc 1 58b x y 11 zzzz 0 0 0 0 11 ASCII header lines zzzz BINARY bytes of data in format specified by x and y above interleaved as specified by the ASCII dataset 58 i When reading or writing a dataset 58b care must be taken that the binary data immediately follows the ASCII header lines and the closing 1 immediately follows the binary data The binary data content is written in the same sequence as the ASCII dataset 58 i e field order sequence The field size is NOT used however the data type int float double content is Note there are no CR LF characters embedded in or following the binary data ASCII UFF The CoCo 80 and EDM software also support the ASCII UFF format The ASCII UFF file format is a form using the ASCII type to represent all the data sets For details see http www sdrl uc edu utf2 58 asc 149 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL MATLAB file This is the standard file that can be imported into Matlab NI TDM file This is a structured data format that is defined and widely used by the LabView from National Instruments User Defined ASCII file This is the ASCII files where you have the freedom to define its attributes and header format CSV Microsoft Excel File This is the ASCII file that the Microsoft Excel can directly read
116. his screen shows several categories of applications These categories mostly match with the template that the CSA uses when it is created with a few exceptions octave analysis and sound level meter applications are grouped in Acoustic Analysis group Any CSA with limiting test are grouped in Limit Test group After entering one of the application groups you will see a list of the CSA projects that are loaded on the CoCo 80 in a scroll down menu on the left and information about each project to the right 16 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Use the up and down arrow buttons to select a project and read the description maximum sampling rate time last modified and publisher information on the right When additional CSA projects are loaded from a PC to the CoCo 80 they will appear on the menu After selecting one CSA project from the menu press the Run soft Button to load and run the CSA project analysis Function to run Min Required Ch Nbr 4 Max Sampling Rate 102 4 kHz Time Last Modified 3 23 2008 Publisher Crystal C54 Script Version 1 3 0 GE Description FFT 4 Calculate the auto power spectra Fiteraps tt For all channels m Figure 11 Analysis screen is used to select a CSA Analysis Soft Buttons Save As saves the current CSA project with a different name This can be used to change project parameters and save the new project without overwriting the original pro
117. ignal better than a signal with large fluctuations Peak Hold This method technically speaking does not involve averaging in the strict sense of the word Instead the average produced by the peak hold method produces a record that at any point represents the maximum envelope among all the component records The equation for a peak hold is yin MAX Cd x n 07 Peak hold is useful for maintaining a record of the highest value attained at each point throughout the sequence of ensembles Peak Hold is not a linear math operation therefore it should be used carefully It is acceptable to use Peak Hold in auto power spectrum measurement but you would not get meaningful results for FRF or Coherence measurement using Peak Hold Peak hold averaging will reset after a specified averaging number is reached Time versus Power Spectrum Averaging Averaging can be applied to either time domain or power spectrum If you want to reduce the spectral estimation variance use power spectral averaging If you want to extract repetitive or periodic small signals from a noisy signal you can use triggered capture and average them in time domain Time averaging must be performed with on a triggered event so that the time signal of one average is correlated with other similar measurements Without time synchronizing mechanism averaging makes no sense 104 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Power Spectrum
118. iles soft button to review the recorded signals Install Engineering Data management EDM software to PC 1 Insert the CoCo 80 Application Software CD into your host computer 2 Click Install EDM entry to install the EDM software and follow the instructions 3 Seta local working folder to your computer 7 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Download Data to the PC 1 Connect the CoCo 80 to your PC using the USB cable provided Note there are two USB ports on the CoCo 80 device Connect the USB cable to the USB client connector shown below Vg m R 7 Cd A Deg i D Z CP bn H ei m Figure 3 Client USB connector for PC communication 2 Browse for the device driver on the CD and the Windows operating system will automatically install the CoCo 80 USB driver on the PC 3 Run the EDM software from the host PC 4 Click on the Search Button on EDM to search the CoCo 80 devices that are connected to the PC 5 After the EDM finds the CoCo 80 click Connect 6 Drag the data file from the CoCo 80 xxx atfx to one of your local folders 7 Using the mouse right click on the signal file xxx atfx on your local folder and click View from the pop up menu 8 Now the EDM software changes to the Analysis page Use the mouse to drag the signal ch1 into the center empty area You will see the waveform that you just recorded with CoCo 80 After completing
119. ill be acquired and included in the average until you press the Hold Button The system does not stop when the average number reaches the averaging number The averaging number only defines the behavior of the averaging function Exponential averaging is intended for continuous averaging to help observe how a signal changes over time or converges to a mean 130 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL CoCo 80 8 Total averaging reached please press F3 to restart a new test m Figure 129 When averaging is complete you can restart a new test with the Run Button Save Averaged Data Data can be saved at any time by pressing the Save Hardware Button This opens a menu with several options Press the Save Button again to save the signals in the save list This can be done in the middle of an average or at the end G T Ah E zs wen d pat Por Ae EE El ep ww IE mm Lei be e np al FFTL Press Save or Enter button to Define signals in the list Save 45 a new project m Figure 130 Save data by pressing the Save hardware button Select Define signals in the list to add or remove signals from the save list or setup automatic data save feature 131 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL 6 BUILT IN DIGITAL INTEGRATION AND FILTERING Introduction to Digital Integration Ideally a measurement is made using a sensor that directly m
120. ination to the nearest Cl authorized service center Cl assumes no risk for damage in transit Following warranty repair the product will be returned to Buyer transportation prepaid FOB Destination If Cl determines that the failure was caused by misuse alteration accident or abnormal condition of operation or handling Cl will provide an estimate of repair costs and obtain authorization before commencing the work Following repair the product will be returned to the Buyer transportation prepaid and the Buyer will be billed for the repair and return transportation charges THIS WARRANTY IS THE BUYER S SOLE AND EXCLUSIVE REMEDY AND IS IN LIEU OF ALL OTHER WARRANTIES EXPRESS OR IMPLIED INCLUDING BUT NOT LIMITED TO ANY IMPLIED WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE CI SHALL NOT BE LIABLE FOR ANY SPECIAL INDIRECT INCIDENTAL OR CONSEQUENTIAL DAMAGES OR LOSSES INCLUDING LOSS OF DATA WHETHER ARISING FROM BREACH OF WARRANTY OR BASED ON CONTRACT TORT RELIANCE OR ANY OTHERTHEORY Since some countries or states do not allow limitation of the term of an implied warranty or exclusion or limitation of incidental or consequential damages the limitations and exclusions of this warranty may not apply to every buyer If any provision of this Warranty is held invalid or unenforceable by a court of competent jurisdiction such holding will not affect the validity or enforceability of any other provision Crystal Instruments Co
121. increased to 100 the standard deviation of the error of the reading is 10 This means that the reading is likely in the neighborhood of 0 1 0 01 VHS Now if this signal has a deterministic nature say a sine wave the spectral estimation error will only be applied to the random portion i e the noisy portion of this signal Coherence Value Affects Accuracy of Spectra Estimate As shown above the spectral estimation error is related to the coherence value between the input and output When signal to noise ratio is low the coherence value will be much less than 1 0 which results in very inaccurate estimation to the FRF and other spectra signals To improve the coherence value the key is to increase the signal intensity of the excitation signal at the frequency range of interest One of the unique features of CoCo is that the random signal of its signal source is well controlled within the analysis frequency band This design allows the excitation focus its energy between DC and analysis frequency The FRF estimation with such excitation will be more accurate Overlap Processing To increase the speed of spectral calculation overlap processing can be used to reduce the measurement time The diagram below shows how the overlap is realized 106 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Signal Captured in the Time Domain emgeet gf H Acquired Signal Data Transformed into FFT Frames No Overlap Pr
122. independent Single Degree Of Freedom systems Each SDOF system can be modeled as a mass fixed to the ground by a spring and a damper in parallel as shown in Figure 97 The frequency response function FRF of this mechanical system is also shown 107 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL 104 output input oe IO 102 Frequency Hz m Figure 97 SDOF system and their frequency response The differential equation of motion for this system is given by m cx kx f t The natural frequency wn and damping ratio can be calculated from the system parameters as C de OI Se and 2 w es where m is the mass k is the spring stiffness and c is the damping coefficient The natural frequency w IS in units of radians per second rad s The typical units displayed on a digital signal analyzer are in Hertz Hz The damping ratio C can also be represented as a percent of critical damping the damping level at which the system experiences no oscillation This is the more common understanding of modal damping Figure 97 illustrates the response of a SDOF system to a transient excitation showing the effect of different damping ratios u t in t sec 0 00 Ww 5 0 rad s u 20 0 in sec 4 00 0 00 0 80 1 60 2 40 3 20 m Figure 98 Step response of a SDOF system with different damping ratios A SDOF system with light damping factor will have longer oscillation in
123. is assumed to be measurement noise CoCo has a unique way to implement the force window This was discussed in the data windowing section in the previous chapter The exponential window is applied to the impulse response signal The exponential window Is used to reduce leakage in the spectrum of the response Accept Reject Because accurate impact testing results depend on the skill of the operator FRF measurements should be made with averaging a standard capability in all modern FFT 125 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL analyzers FRFs should be measured using at least 4 impacts per measurement Since one or two of the impacts during the measurement process may be bad hits too hard causing saturation too soft causing poor coherence or a double hit causing distortion in the spectrum an FFT analyzer designed for impact testing should have the ability to accept or reject the result of each impact after inspecting the impact signals An accept reject capability saves a lot of time during impact testing since you don t have to redo all measurements in the averaging process after one bad hit 4 Modal Damping Estimation The width of the resonance peak is a measure of modal damping The resonance peak width should also be the same for all FRF measurements meaning that modal damping is the same in every FRF measurement good analyzer should provide an accurate damping factor estimate CoCo uses a curv
124. ith the recall feature Recalled signals can be overlaid with live signals for comparison or displayed in a separate window Signals can also be un recalled which removed them from all displays but does not affect the data saved on the CoCo To recall the signals that you just saved simply press the Recall hard button To recall a signal that you previously saved press the File Button then press the F1 Files Button then press the F5 Review Button Next use the up and down arrow buttons to highlight a signal to be recalled and press the F3 Recall Button Next highlight a signal from the Record Files list and then press the F3 Recall Button Record Files General Information Version 1 File Name User Admin Test Note Default Test Time Created 8 9 2008 14 24 54 Signals 4 Cut ijt APSich2 APS ch3 APS ch4 m Figure 73 File review screen for recalling signals The CoCo will show a menu listing all available windows that this signal can be recalled into The last item is always Recall the signal to a new window This item will create a new display window 81 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL in the current active project and display the recalled signal into this window Other selections will allow the recalled signal to be overlaid with the others After a signal is recalled it can then be un recalled This removes the signal from the all displays however the original data file r
125. itized time waveform The sine wave is not smooth because of the low sampling rate relative to the frequency of the signal However the well known Nyquist principle indicates that the frequency estimate from the FFT will be accurate as long as the sampling rate is 88 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL more than twice of the signal frequency The frequency spectrum of the period signal will show the accurate frequency and level Note for a more accurate sample of the time waveform a higher sampling rate is required Figure 81 illustrates a windowing function applied to a pure sine tone 8160035 _ AP Sich 1 200 D D D 0 200 EUpk Linear Scaling 0 600 0 400 Mag NI 0 peak ha D 0 000 1000 000 2000 000 2000 000 Frequency Hz e Wel OI T E E TT 950 000 1000 000 1020 000 1100 000 Frequency Hz m Figure 81 Hanning windowing function applied to a pure sine tone The top picture is displayed in EUpk i e the peak of the spectrum is scaled to the actual 0 peak level which is 1 0 in this case The bottom picture shows the same signal with the dB scale applied Since we use OdB as reference the 1 0 Vpk is now scaled to 0 0 dB With the dB display we can see frequency points around the peak causing by the Hanning window In many DSA products amplitude correction is automatically applied when you select different Spectrum Types For details
126. ject Delete removes the CSA project from the CoCo 80 flash memory The CSA project can be reloaded from the PC if it is accidentally deleted Move to lets you move the CSA project file to another group Cancel returns to the previous screen Run loads the selected project and starts the display The Enter button also loads and starts the selected project 17 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Display Button Display The Display Button changes the screen from the current screen to a center management window for display management Pressing the Display button and Enter will always lead to displaying the current active window The following screen shows the Signal Display Window This is the most frequently used window in this instrument r PER Grape Ci E el Ee m a Marat edd aat td E m Figure 12 Display screen shows a window with one trace A signal display window can have either one or two traces The software allows three types of signal display windows A window with one trace a window with top and bottom traces a window with a 3D waterfall trace The picture below shows a window with two traces h LA Wald be Wb Wi KA Net ke j Auto m Figure 13 Two trace window 18 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL A trace is defined as area display with an axis that can show multiple signals of th
127. l the EDM software on the PG Install the RNDIS USB driver on the PG 2 Connect CoCo 80 to the PC through the provided USB cable This cable has a mini client port connecting to the CoCo 80 and a flat USB port connecting to the PC Connect CoCo 80 to a PC directly using Ethemet via cross over cable Another way to connect the CoCo 80 to a PC directly is to use the Ethernet port and a CAT 5 cross over cable The advantage of using Ethernet compared to USB is that the data transfer speed is faster with Ethernet The disadvantage is that you must configure the IP settings on the host PC so it can communicate with the CoCo 80 In this case both PC and CoCo 80 must be configured with a fixed IP address with the same subnet mask The host PC can also use the Alternative Configuration feature for convenient communication with its office local area network Alternate Configuration is a networking option within Windows to maintain seamless operations on both office and home networks without having to manually reconfigure TCP IP settings Refer to the Microsoft support website for more information of this feature http support microsoft com kb 283676 Connect CoCo 80 to a local network using Ethernet In this connection case if DHCP server is not installed on the local area network both PC and CoCo 80 must be configured with a fixed IP address with the same subnet mask If DHCP server is installed then both the PC and the CoCo 80 can use the Obtain an
128. le Measurement Page shows the Measurement Settings including Input Output Display Preference Acquisition Mode System Calibration Self Test and Testing Log x Input Cutput Display Application Channels Channel Preference Group D GA SS SS Acquisition System Self Test Testing Log Mode Calibration System Run YOC m Figure 39 Setup Measurement Screen shows the Input Output Display and Acquisition Mode settings CSA Application Group is the same as pressing Analysis button Input Channels changes the display to the Inout Channel Table This is described above under the Analysis Parameters section Output Channel changes the display to the Output Parameter screen This is described above under the Analysis Parameters section System Calibration is used to calibrate the input and output channels This procedure requires a high precision calibrated AC DC volt meter Cl recommends that this task is performed by the factory or designated companies that are familiar with the calibration process The picture below shows one of the ten steps to conduct the calibration It will take about 10 minutes to complete a calibration 39 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Step 1 of 10 Introduction You need an accurate voltmeter that is capable of measuring DC and AC up to TkH2 to calibrate this syster You also need the output cable provided by the Factory The calibration accuracy
129. le if in the CSA an RMS measurement is derived from ch1 this RMS time stream can be used as a trigger source Trigger Condition Trigger Condition defines when a trigger is detected based on the signal level and the slope The four choices are 1 Trigger Source gt High Level rising edge 2 Trigger Source lt Low Level falling edge 3 Low Level lt Trigger Source lt High Level level trigger 4 Trigger Source gt High Level OR Trigger Source lt Low Level edge trigger There are two types of trigger detection one is called edge detection the second level detection In the trigger conditions above 1 2 and 4 are edge detection and 3 the level detection Edge 69 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL detection compares at least two sample points against the threshold level Level detection only detects one sample point When Free Run is selected trigger source and level are not needed The table below visually explains when the trigger event will happen in these four conditions The red mark shows the instant in time that the trigger event is detected Trigger Condition Visual Explanation S Trigger Source gt High Level rising edge High threshold level Trigger Source lt Low Level falling edge Low threshold level Low Level lt Trigger Source lt High Level level trigger High threshold level Low threshold level Trigger Source gt High Level O
130. led at such a sampling rate that is perfectly synchronized with the signal period so that with a block of capture an integer number of cycles of the signal are always acquired For example if a sine wave has a frequency of 1000Hz and the sampling rate is set to 8000Hz Each sine cycle would have 8 integer points If 1024 data points are acquired then 128 complete cycles of the signal are captured In this case with no window applied you still can get a leakage free spectrum Figure 90 shows a sine signal at 1000 Hz with no leakage resulting in a sharp spike Figure 91 shows the spectrum of a 1010 Hz signal with significant leakage resulting in a wide peak The spectrum has significant energy outside the narrow 1010 Hz frequency It is said that the energy leaks out into the surrounding frequencies m Figure 90 Sine spectrum with no leakage m Figure 91 Sine spectrum with significant leakage 97 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Several windowing functions have been developed to reduce the leakage effect The picture below shows a Flattop window applied to the same sine signal with frequency 1010Hz m Figure 92 Sine spectrum with Flattop windowing function When Flattop window is used the leakage effect is reduced Both the sine peak and noise floor can be seen now However such data windowing operation also makes the spectrum peak fatter and less accurate In the rest of the se
131. ls from a typical impact test are shown in Figure 10 124 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL imgs p d EH LS LEO 2 2 a ad or Frequency Magnitude dE 500 1200 1200 2000 2500 3 000 Frequency Figure 119 Typical impact test data Top left shows excitation force impulse time signal top right shows response acceleration time signal and bottom shows FRF spectrum Impact Test Analyzer Settings The following settings are used for impact testing 1 Trigger Setup including trigger level and pre trigger delay are used to capture the transient signal for FRF processing It is important to capture the entire short transient signal it in the sampling window of the FFT analyzer To insure that the entire signal is captured the analyzer must be able to capture the impulse and impulse response signals prior to the occurrence of the impulse with the pre trigger Force amp Exponential Windows Two common time domain windows that are used in impact testing are the force and exponential windows These windows are applied to the signals after they are sampled but before the FFT is computed in the analyzer The force window is used to remove noise from the impulse force signal Ideally an impulse signal is non zero for a small portion of the sampling window and zero for the remainder of the window time period Any non zero data following the impulse signal in the sampling window
132. me signal significantly hence causing a distortion in its frequency domain Actual Input A A KN Ch Py i IW d j i i I d i I I Ume Au d roy i i d V Windowed Input Nor Periodic time Assumed Inout i UI i hme m Figure 89 Illustration of a non periodic signal resulting from sampling If there are two sinusoids with different frequencies leakage can interfere with the ability to distinguish them spectrally If their frequencies are dissimilar then the leakage interferes when one sinusoid is much smaller in amplitude than the other That is its spectral component can be hidden or masked by the leakage from the larger component But when the frequencies are near each other the leakage can be sufficient to interfere even when the sinusoids are equal strength that is they become undetectable 96 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL There are two possible scenarios that leakage does not occur The first is that when the whole time capture is long enough to cover the complete duration of the signals This can occur with short transient signals For example in a hammer test if the time capture is long enough it may extend to the point where the signal decays to zero In this case data window is not needed The second case is when a periodic signal is samp
133. mes for averaging to reduce the time required to acquire a large number of averages Mode Condition Manual 4rm Trigger chi gt High Level Trig Src chi Low Level 1 0 High Level 1 0 m Figure 126 Overlap rate for transient capture After the Parameter Settings are specified the CoCo begins to wait for a trigger event A window displays the time elapsed before a trigger event is detected 129 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL m Figure 127 Waiting for trigger message When a trigger event is detected and Manual Am Trigger is selected then a small window will show the data frame and give you the option to accept or reject the data Accept will include the frame into the average and then ask you to proceed to the next trigger by pressing the Next button Reject will discard the frame not include it in the average and return to the waiting for trigger mode If Auto Arm Trigger mode is selected then the system will automatically return to the wait mode after each trigger event with no user intervention m Figure 128 Accept Reject display for transient capture The frame average number is displayed in the status bar to help you monitor how many averages have been recorded When the averaging mode is set to linear and you reached the averaging number you are prompted to restart a new test by pressing the Run Button When the averaging mode is set to exponential then new frames w
134. n below 3 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL d CI Technical Support Site Home Hardwar CoCo 20 Serial Number 23689 Hardware warranty expired Dec 05 2008 363 days left Detail Version Information Firmware 0 0 9 DataFlashVersion 1 0 0 EMBSD0 3 0 4 EPC amp O 6 0 6 EPCD8O 5 0 5 Hardware Configurations System CPU XScale PXA270 Processor at 520MHz Total Storage o Total RAM 128MB o Total flash memory used for system and data sto Audio o 3 5mm earphone connector o Build in speaker phone o Build in microphone Ethernet 100 BaseT RJ45 connector USB host 1 1 type A connector SD card MMC SD SDIO standard System reset pin Input Channel number amp DSP TMS320C67xx floating point 5 input types DC Differential DC Single End AC Dif m Figure 2 Crystal Instruments CoCo 80 Support Website The latest CoCo 80 application software device drivers or CSA projects can be downloaded while the CoCo 80 subscription is maintained Limited Warranty amp Limitation of Liability Each Cl product is warranted to be free from defects in material and workmanship under normal use and service The warranty period is one year for the CoCo 80 hardware and its accessories The warranty period begins on the date of shipment Parts product repairs and services are warranted for 90 days This warranty extends only to the original buyer or end user customer of a CI authori
135. n status of software option components for serial number 24650 Software Option Description Status Eu Frequency response analysis with Net Ge swept sine source Installed Apply limits to any block signals Mot and trigger certain events when Installed Mot Installed Order tracks RPM spectrum RPM Mot processing Installed m Figure 33 Software Options Limiting Test Histogram Histogram and statistics analysis Order Tracking If you press the F1 Check Options button the CoCo will check the available software options that can be installed on the remote Cl server Audio allows you to change the audio feedback settings including keypad power button and alarm sounds The speaker volume and microphone level can also be changed Voice annotation is controlled through Audio setup as well Audio Audio amp Sound Enable Sound for Keypad Sound Power Button Sound Soundi Alarm Sound Sound1 Use microphone to record the voice annotation Use headphone ta listen to any input channel Speaker Volume L 1m0 Microphone Level L imo m Figure 34 Audio Settings including Voice Annotation Among these settings the Use microphone to record the voice annotation and Use headphone to listen to any input channel are advanced audio functions User needs to purchase this software option to enable such setting Memory displays the status of the CoCo 80 memory This includes local memory used by the CoCo 80
136. n this slight inaccuracy Is integrated in order to determine velocity and displacement it becomes quite large As a result the velocity and displacement data are grossly inaccurate A piezoresistive or variable capacitance accelerometer is a better choice for low frequency signals and for integration These types of sensors measure accelerations accurately at frequencies approaching 0 Hz Therefore the integration calculation of velocity and position can be used to produce accurate results Calculation Errors in Digital Integration Two types of calculation errors can be caused by digital integration low sampling rate and DC offset The sampling rate of a signal must be high enough so that the digital signal can accurately depict the analog signal shape Some people may think that according to the Nyquist sampling theorem as long as the sampling speed is more than twice of the frequency content of the signals before the integration the integration results should be acceptable This is not true Satisfying the Nyquist frequency only ensures an accurate estimate of the frequency of a measurement Integration error can still occur of a signal is not sampled at more than twice the signal frequency Figure 131 shows a 1kHz sine wave sampled at 8kHz and 5 12kHz 133 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL amp SIG0013 BLOCK ch1 0 024 0 025 0 026 0 027 0 028 0 029 0 030 0 031 0 032 0 033 Time seco
137. nagement The nature of signal measurement generates a large number of records The EDM software provides tools to manage this data to simplify searching review and exporting the data Data can be searched by key words date or time size or other file attrioutes Data can be previewed via 140 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL thumbnail representations of the data or by text file attributes Data can be replayed within the search tool including the ability to scroll through a long time stream to verify that the record contains the required properties EDM simplifies the process of exporting data from the native ASAM ODS format to other popular universal formats including UFF BUFF and ASCII Data Analysis The EDM software includes basic analysis tools that help measure signal characteristics such as zoom and pan and cursors Multiple signals can be overlaid on one trace for comparison Long time streams can be played back and time or frequency data can be displayed CoCo 80 PC Communication The first step in downloading data from the CoCo 80 to a PC is to establish communication between the two devices CoCo 80 is equipped with a number of hardware connectivity functions for easy communication with a host PC These include e USB port e 100MbaseT Ethernet e Wireless 802 11b g using SD card You can choose one of following four typical connections e Connect CoCo 80 to a PC directly using a
138. nal microphone must be ordered from CI It is designed so that when the microphone button is pushed the voice annotation recording is activated The microphone jack connector is on the left side of the peripheral panel Do not use any microphone other than the specified Cl microphone because without the microphone button hardware you will not be able to start a voice annotation recording m Figure 59 Microphone with push button part CoCo A12 Audio Functions The audio functions are controlled through the CoCo Setup gt Audio Setup screen Audio Audio amp Sound Enable Sound for Keypad Sound Power Button Sound Sounds Alarm Sound Sound3 BB Use microphone to record voice annotation BB Use headphones to listen to any input channel Speaker Volume IT 100 00 Microphone Level TT m Figure 60 Audio Setting page Keypad Sound Enable and select the internal soeaker sound output when any of the buttons are pressed 57 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Power Button Sound Enable and select the internal speaker sound output when the power button is pressed Alarm Sound Enable and select the internal speaker sound output for system alarms Use microphone to record the voice annotation Enable the external microphone recording function When this item is checked and the user presses the connected microphone button the voice annotation is recorded until the button is rele
139. ncy domain To perform FFT based measurements however you need to understand the fundamental issues and computations involved This Chapter describes some of the basic signal analysis computations discusses antialiasing and acquisition front end for FFT based signal analysis explains how to use windowing functions correctly explains some spectrum computations and shows you how to use FFT based functions for some typical measurements General Theory of Spectral Analysis In this Chapter we will use standard notation for different signals Each type of signal will be represented by one specific letter For example G stands for a one side power spectrum while H stands for a transfer function The following table defines the symbols used in this Chapter Cyx Coherence function between input signal x and output signal y GXxx Auto spectral function one sided of signal x Gyx Cross spectral function one sided between input signal x and output signal y Hyx Transfer function Frequency Response between input signal x and output signal y k Index of a discrete sample Rxx Auto correlation function of signal x Ryx Cross correlation function between input signal x and output signal y Sx Linear spectral function of signal x Sxx Instantaneous auto spectral function one sided of signal x Syx Instantaneous cross spectral function one sided between input signal x and output signal y t Time variable x t Time history record
140. ndom or mixed random and periodic Averaged measurements can yield either higher signal to noise ratios or improved statistical accuracy Typically three types of averaging methods are available in DSA products They are Linear Averaging Exponential Averaging and Peak Hold Linear Averaging In linear averaging each set of data a record contributes equally to the average The value at any point in the linear average in given by the equation Sum of Records A d verage N N is the total number of the records The advantage of this averaging method is that it is faster to compute and the result is un biased However this method is suitable only for analyzing short signal records or stationary signals since the average tends to stabilize The contribution of new records eventually will cease to change the value of the average Usually a target average number is defined The algorithm is made so that before the target average number reaches the process can be stopped and the averaged result can still be used 102 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL When the specified target averaging number is reached the instrument usually will stop the acquisition and wait for the instruction for another collection of data acquisition Moving Linear Averaging In a regular Linear Average the data rate of the output of the averaging operator is only 1 N of that of the original signal Therefore more av
141. nds Signals SIG0014 BLOCK ch1 4 gt x Q H HERE Begin 0 0240 End0 0330 amp SIG0014 BLOCK ch1 1 000 0 500 0 000 0 500 1 000 0 024 0 026 0 028 0 029 0 031 0 033 Time seconds m Figure 131 A 1 kHz sine wave sampled at 8 kHz top and also sampled at 5 12 kHz bottom It is clear that the higher the sampling frequency the closer this digitized signal is to the true analog waveform When the sampling rate is low the digital integration will have significant calculation error For example the 5 12 kHz sampled signal is not symmetric about 0 volts so the integration will drift and a double integration may grow with accumulated error very fast In general you should use a sampling rate 10 times higher than the frequency content that is of interest in the signal when you apply numerical integration DC offset is the second type of digital integration error and can be more severe It is caused by any measurement error before integration and may result in huge amplitude errors after the integration Figure 132 shows how a small measurement error in acceleration will create a constant DC offset in the acceleration integrated to compute velocity and result in a drift and eventually an infinite large magnitude of displacement after double integration Displacement Velocity N Acceleration m Figure 132 A small error in acceleration results in a DC offset in velocity and a huge drift
142. nput Playback the Voice Annotations on CoCo To play back the voice annotation first press the File button then the F1 Files then the F2 Voice button Record Files 2 Files Total iser 10 13 MB Page 1 Total Page 1 File Name Create Time Test Mote Size i RECOOG 8 26 2000 2 41 12 DeFault Test 14 85 MB Recalled Copy to m Figure 63 Play back voice annotations from the File View The F3 Play button allows you to hear the previously recorded voice annotation Then you can use the F1 Previous Annotation or F2 Next Annotation Buttons to play all the annotations If the Voice button is not shown it means the signal file saved has no voice annotation attached 59 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Annotations of REC0088 Annotation Signal Time Duration eS ea nn TSS SoS a a Annotation a EE 2008 2 46 20 AM g AnnotationdO m Figure 64 Play all annotations using Next and Previous buttons Voice annotations will be listed under each recorded or saved signal files and can be played back with EDM PC software Playback the recorded signals from output channel The CoCo can playback any of the recorded signals from its output channel To do so open a recorded file and press F5 the Playback button been moved renamed or deleted Verify that the lnk points to the correct fie and locati If the user made voice annotations while the time stream is
143. nts COCO 80 USER S MANUAL where Power is the measured power and Pref is the reference power Use the following equation to compute the ratio in decibels from amplitude values dB 20log10 Ampl Aref where Ampl is the measured amplitude and Aref is the reference amplitude When using amplitude or power as the amplitude squared of the same signal the resulting decibel level is exactly the same Multiplying the decibel ratio by two is equivalent to having a squared ratio Therefore you obtain the same decibel level and display regardless of whether you use the amplitude or power spectrum As shown in the preceding equations for power and amplitude you must supply a reference for a measure in decibels This reference then corresponds to the 0 dB level Different conventions are used for different types of signals A common convention is to use the reference 1 Vrms for amplitude or 1 Vrms squared for power yielding a unit in dBV or dBVrms In this case 1 Vrms corresponds to 0 dB Another common form of dB is dBm which corresponds to a reference of 1 mW into a load of 50 Q for radio frequencies where 0 dB is 0 22 Vrms or 600 for audio frequencies where 0 dB is 0 78 Vrms The picture below shows a sine wave with 1V amplitude displayed in dB Because the reference is 1Vpk it shows the peak value of this sine wave as OaB m Figure 113 Show a 1Vpk sine signal in frequency domain with dB scaling Another display format is called Log
144. o initiate the CSA Editor click on the CSA Editor icon on the upper left corner of EDM The Analog Signal Conditioning and Data Pre Conditioning In a global picture the signals will go through the following stages in an analyzer Analog AID Optional Signal i Converter High Pass Filter Conditioning and Integration Data Spectral m Conditioning gt Analysis y CoCo First the analog signals will be processed by the analog signal conditioning circuitry It usually includes an input mode selection logic the high pass filter for AC coupling and constant current source for IEPE Then the analog signals will be digitized simultaneously by multiple A D converters The digital signals coming out of A D converters after a unique calibration process will be fed into the DSP chip inside of the CoCo box 65 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL The CoCo may first turn on a pre data conditioning algorithm This pre data conditioning algorithm may apply the high pass filters so to reduce the DC drift or convert the acceleration signals into velocity or displacement It will also apply the appropriate engineering unit setting to the input signals Then the data streams will be fed into a user controlled Data Conditioning module and then spectral analysis This part will be explained in detail in the next section The
145. ocessing Acquired Signal Post Processed with Overlap FFTs 1024 Samples 1024 Samples 1024 Samples FFTs Overlap Samples Overlap Interval Samples 1024 Samples 1024 Samples m Figure 96 Illustration of overlap processing As shown in this picture when a frame of new data is acquired after passing the Acquisition Mode control only a portion of the new data will be used Overlap calculation will speed up the calculation with the same target average number The percentage of overlap is called overlap ratio 25 overlap means 25 of the old data will be used for each spectral processing 0 overlap means that no old data will be reused Overlap processing can improve the accuracy of spectral estimation This is because when a data window is applied some useful information is attenuated by the data window on two ends of each block However it is not true that the higher the overlap ratio the higher the spectral estimation accuracy For Hanning window when the overlap ratio is more than 50 the estimation accuracy of the spectra will not be improved Another advantage to apply overlap processing is that it helps to update the display more quickly Single Degree of Freedom System This section briefly discusses the single degree of freedom SDOF system as background for the frequency response function and damping estimation methods The vibration nature of a mechanical structure can be decomposed into multiple relatively
146. od is used to compute the spectra with area correction Using Sx Step 3 Calculate the Power Spectrum Sxx Sx Sx AmpCorr Or calculate the Power Spectral Density Sx Sx T EnergyCorr Or calculate the Energy Spectral Density Sx Sx T EnergyCorr where T is the time duration of the capture The symbol is for complex conjugation EnergyCorr is a factor for energy correction which is defined as N 1 1 EnergyCorr FT H w k k 0 Nis the total number of the samples and w k is window function For any power spectral measurement of the three types listed above the EU is automatically chosen as EU m because only EU ns has a physical meaning related to signal power After the power spectra are calculated the averaging operation will be applied More details will be discussed in the next sections for averaging operation Spectrum Types Several Spectrum Types are given for both Linear Spectrum and Power Spectrum measurements in CoCo and EDM The concept of spectrum type is explained below in detail First let s consider the signals with periodic nature These can be the signals measured from a rotating machine bearing gearing or anything that repeats In this case we would be interested in amplitude changes at fundamental frequencies harmonics or sub harmonics In this case you can choose a spectrum type of EUpk EUpkok or EU ms 90 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL A secon
147. of the signals which are with the same type as the first one to overlay them Set a Window with Two Traces To set up a window with two traces first select Add a Window with two Traces Then the following screen will be displayed 21 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Add or remove window and change signals in trace Press Enter key to select or de select signal in trace 0 emm Native channel chi chez l Nath e channel t ch ch3 cg _ Native WV channel chi d cht e channel cht BLOCKichi e E block signal BLOCK LC hz IE une block signal BLOCK LC h3 lock signal BLOCK fe cha RS IC SEET ble ck lock signal R Press SHIFT key to select T EN VER m Figure 16 Edit window screen is used to add delete window and add signals to each trace In this screen you can set the top and bottom trace by selecting appropriate signals in the same way as you Set up the one trace window To switch between top and bottom traces within the window use SHIFT hard key View Mode The signals can be displayed in either text or graphic plot mode When it is in the text mode one of the signatures of the signal must be selected Current value Peak value Pk Pk Value lh dax imum O alue Minimum Value Averaged Value m Figure 17 In screen of Trace and Windows Setting different view mode can be selected Signals Displayed in Trace shows the signals that a
148. oject runs on CoCo Notice that the time streams after the data conditioning can also be selected as trigger candidates Also note that items not specified as trigger candidates can not be used as triggers on the CoCo without modifying the EDM script and downloading it to the CoCo 126 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Data Conditioning Acquistion Mode Signal Analysis Signal Summary Input Time Streams Trigger and Block Acquisition 1 chi Set as Trigger Source Candidate 2 ch2 Set as Trigger Source Candidate 3 ch3 Set as Trigger Source Candidate nu Ce et as Trigger Source Candidate s No Block Acquisition Set as Trigger Source Candidate Block Acquisition m Figure 121 CSA Editor Wizard Acquisition Trigger and Block Acquisition settings To acquire the data block by block enable the appropriate acquisition modes For a hammer test you must enable Manual Arm Trigger which will activate Accept Reject logic when a block of signals are captured on CoCo Acquistion Parameters Setup a Acquisition Mode Free run Continuous after Trigger Single Shot with Trigger 7 Single Shot without Trigger d Auto Arm Trigger 7 Manual rm Trigger m Figure 122 Acquisition Mode selection You must validate and upload the CSA to CoCo after editing CoCo Hardware Operation for Transient Capture Select a CSA Project This section discusses the CoCo settings that are sp
149. omated schedule can be developed for recording the time streams saving the block signals or data points e Restart e Hold e Run Duration regardless Trigger e Run Duration after Trigger e Waiting for one time e LOOP e END LOOP e Limit check ON e Limit check OFF e Start Recording e Stop Recording e Save Signals e Turn signal source ON e Turn signal source OFF e Activate Timer to Save Signals e Deactivate Timer to Stop Saving Signals e Set all input mode To make a schedule first go to the Schedule Setup screen 79 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Sample Rate Input Channels Output Channel Acquisition Mode Display Preferenc Analysis Parameters Time Stream Recording Setup ge PA TT Test Schedule Settings Run Duration 00 00 10 Limit check ON Run Duration Limit check OFF Save Signals Hol d Press Display key 3sec to enable the selected schedule Insert To activate the schedule press the Display button for more than 3 seconds then release the button 80 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL To deactivate the schedule press F6 the Exit button in the signal display screen Recall Signals Signals that are the result of a current measurement are named live signals Occasionally it is helpful to compare live signals with previously saved signals and stored on the CoCo device This can be done w
150. or a cooling fan reducing operating noise The fully charged battery life is up to many hours An AC adapter can be used any time to charge the device and supports unlimited hours of operation Compared to handheld data acquisition systems and signal analyzers from the other providers CoCo 80 delivers a higher measurement dynamic range and accuracy recording throughput rate and real time analysis performance It also provides more powerful communication peripherals Compared to PC tethered data acquisition systems and signal analyzers CoCo 80 does not have the drawbacks such as unreliable data transfer using connection cables CoCo 80 does not need any additional PC or laptop to operate during field data acquisition Hence CoCo 80 is much more reliable and easy to operate 2 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL On Line Support To access product information about your CoCo 80 please go to the product page of Cl website at http www go ci com support asp log in with the serial number of the CoCo 80 and the password included in your shipping documents After you log in you will be able to review and download the latest information which is restricted to CoCo80 users including e Product Information e New CSA projects e User s Manual e Shipping and Repair History e User Forum e Technical Support e Software Updates e Technical Issues A typical page of Cl Technical Support website is show
151. originally developed as 80 character card image ASCII records that occur in a specific order according to each UF format As computer files became routinely available single UF formats were concatenated into computer file structures Recently a hybrid UF file structure UF Dataset 58 Binary was developed for experimental data that allows data to be stored in a more efficient binary format Before the introduction of ASAM ODS the use of the Universal File Format as a de facto standard has been of great value to the experimental dynamics vibration and acoustic community particularly in the area of modal analysis Both users and vendors have benefited from this de facto standard The EDM software will be able to export the data into UFF Dataset 58 and BUFF Dataset Binary 58 For more information on UFF refer to http www sdrl uc edu uff uff html The Binary 58 Universal File Format BUFF The CoCo 80 and EDM software also support the BUFF format The basic ASCII universal file format for data is universal file format 58 This format is completely documented by SDRC and a copy of that documentation is on the UC SDRL web site www sdrl uc edu UFF2 58 asc The universal file format always begins with two records that are prior to the information defined by each universal file format and ends with a record that is placed after the information defined by the format First of all all records are 80 character ASCII records for the basic uni
152. orm the time streams into block by block time signals It sets the trigger and the overlapping processing Before the Acquisition Mode stage the instrument acts as a data recorder while after the Acquisition Mode it is acts as a signal analyzer Data recorder Signal Analyzer m Figure 117 Transient capture operation on CoCo Besides Acquisition Mode you must first enable at least one time stream as a trigger candidate in the CSA Editor Trigger candidates are those time streams that can be selected as a trigger source The names of these trigger candidates will be passed to the CoCo During runtime one of the trigger source candidates must be selected as the trigger source Impact Hammer Testing Typically impact hammer testing is conducted with a signal analyzer to measure FRFs of the device under test The FRFs can be used to determine the modal properties of the device such as the natural frequencies and damping ratios In addition the data can be exported to third party modal analysis software to compute mode shapes An impact hammer test is the most common method of measuring FRFs The hammer imparts a transient impulsive force excitation to the device The impact is intended to excite a wide range of frequencies so that the DSA can measure the vibration of the device across this range of frequencies The bandwidth or frequency content of the excitation input depends on the size and type of impact hammer that is used Th
153. peak level volt Acquisition Mode is used to configure how the data blocks are captured from the conditioned time streams into the signal analyzer phase The selections are Free run Continuous after trigger Single Shot by user Single Shot with trigger Multiple shots with trigger auto rearm Multiple shots with trigger manual rearm It is important to note that the Acquisition Mode is designed for signal analysis functions only such as spectrum measurements The Data conditioning process is not affected by the Acquisition Mode For example data recording will continue uninterrupted regardless of the Acquisition Mode Acquisition Mode setting is dependent on the selected CSA Schedule Setup is used to configure the automated test 27 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL et amete Sample Rabe Input Channels utput Channel Acouskon Mode Display Preferences Analysis Parameters Time Stream Recording Setup Signal Snapshot Save Setup Link Alarm Setur m Figure 24 Schedule Setup Testing schedule automatically controls the test duration and imitate human operation Multiple testing schedules can be developed and one Is executed at a time A testing schedule event can include the following events Loop End Loop Run Duration Hold Limit Check on Limit Check off Start Recording Stop Recording Save Signals Turn Signal Source On and Turn Signal Source Off Activating the
154. quence number added This approach will prevent overwriting the old CSA files that may have been changed by the user If the connection to the Internet could not be established please press the Setup button and click on the Connections icon This will lead you to the Ethernet network setup The most common problem is caused by inappropriate IP address setting Most often your LAN requires you set up the IP as Dynamically obtain an IP via DHCP Please refer to section Configuring the CoCo 80 Network Settings in this manual for more details Advanced Audio Functions CoCo 2 CoCo 80 and CoCo 90 are all equipped with advanced audio functions These audio functions allow you to listen to the vibration or any measurement quantity or record voice annotations during signal recording This document describes how to use the audio functions The advanced audio features can be summarized as following e You can listen to any measurement input using headphones without interrupting the measurement or recording process e The audio monitoring is automatically scaled to the listening range and the headphone audio can be manually adjusted e Youcan record voice annotations at any time and length during time stream recording e A customized microphone is available with a push button to control voice annotation recording e Voice annotations can be replayed on the CoCo hardware through headphones e Voice annotations are attached to each recor
155. ration ms 100 Peak Output Level Volt 1 m Figure 111 Arbitrary waveform settings To start the output channel press the Enable Button Create Display Window and Set up the Trace To create a display window select Trace and Window Setting under the Param Button Use the soft buttons to add or delete a window clear the signals from the current window select all signals or change the view mode to show a numerical value Change the signals in each window by selecting a specific window tab with the left or right buttons then editing the window settings Add or remove window and change signals in trace Press Enter key to select or de select a signal in trace I En z ne Windowd Hich chi Afch3 chi Hich4 ch1 30 Windowe Gich1 ch1 Windows chi Native channel chi che Native channel che ch3 Native channel ch3 cht Native channel ch4 BLOCE chi Captured block signal Add Window sts Add a Window with 3D waterfall trace Add Window with kwo Traces m Figure 112 CoCo Add Window display dB and Linear Magnitude Most often amplitude or power spectra are shown in the logarithmic unit decibels dB Using this unit of measure it is easy to view wide dynamic ranges that is it is easy to see small signal components in the presence of large ones The decibel is a unit of ratio and is computed as follows dB 10logi0 Power Pref 119 COCO 80 BASIC DSA USER MANUAL CRYSTAL instrume
156. rd zero How to Choose the Right Data Window In this section we will discuss how to choose the data window Figure 93 shows the spectral shape of four typical windows corresponding to their time waveform 99 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Rectangular amp oo Magnitude dB np 5 10 15 20 0 1 S 20 o 0 8 E 2 A0 0 6 E E 0 4 c 60 i 0 2 E B0 o 15 20 5 10 l Sample m Figure 93 Spectral shape of common windowing functions It can be seen that the spectral shape of the data window Is always symmetric The spectral shape can be described as a main lobe and several side lobes 100 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments 6dB Peak side lobe level Main lobe width COCO 80 USER S MANUAL Frequency m Figure 94 Window frequency response showing main lobe and side lobes The following table lists the characteristics of several data windows Frequency Characteristics of Data Windows Window 3 dB Main Lobe 6 dB Main Maximum Width bins Lobe Width Side Lobe Level dB Uniform none Main Lobe The center of the main lobe of a window occurs at each frequency component of the time domain signal By convention to characterize the shape of the main lobe the widths of the main lobe at 3 dB and 6 dB below the main lobe peak describe the width of the main lobe The unit of m
157. re attached to the selected trace Signals can be added to the current trace by selecting them with the arrow buttons and pressing the Enter button to highlight the signal All highlighted signals are displayed in the current trace Only signals of the same dimensions can be included in the same trace For example time and frequency type signals cannot be included in the same trace Trace and Window Setting Menu Soft Buttons Add Window creates a new window in the Window List Windows are named sequentially as Window1 Window2 etc Delete Window removed the highlighted window from the Window List 22 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Clear Signals removes all signals from the highlighted trace Select All Signals adds all signals to the highlighted trace Cancel returns to the previous screen without changing the trace definitions OK saves the changes to the trace definitions and returns to the previous screen Param Soft Button opens the Parameter Settings Menu This menu allows you to set parameters for the sample rate input and output channels triggering analysis and time stream recording Parameter Settings Sample Hate Input Channels Output Channel Schedule Setup Display Preferences Analysis Parameters Time Stream Recording Setup Signal Snapshot Save Setup m Figure 18 Parameter Settings menu Sample Rate is used to set the sampling rate for data acquisition Use
158. re below shows a recalled signal in green color overlaid with a live signal in yellow m Figure 78 Live signal overlaid with recalled signal The picture below shows the saved RPM trace signal in octave analysis that is overlaid with the current live measurement 83 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL m Figure 79 RPM live signal overlaid with recalled signal 84 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL 4 BASICS OF DYNAMIG SIGNAL ANALYSIS DSA often referred to Dynamic Signal Analysis or Dynamic Signal Analyzer depending on the context Is an application area of digital signal processing technology Compared to general data acquisition and time domain analysis DSA instruments and math tools focus more on the dynamic aspect of the signals such as frequency response dynamic range total harmonic distortion phase match amplitude flatness etc In recent years time domain data acquisition devices and DSA instruments have gradually converged together More and more time domain instruments such as oscilloscopes can do frequency analysis while more and more dynamic signal analyzers can do long time data recording DSA uses various different technology of digital signal processing Among them the most fundamental and popular technology is based on the so called the Fast Fourier Transform FFT The FFT transforms the time domain signals into the freque
159. rnnnvvrnnnvnrnnnvnrnnnnnrnnnnnrnnnnnsnnnnesnnnnesrnnnennnnnensnnnensnnnennnnenn 116 Select a CSA H dree eden Gees erat 116 Set Analysis Parameters for Spectral Analyse 116 Set the Spectrum E 117 Set the Output Channel Parameters rrsrrrrnnvernnnvrrnnnvrrrnnvrrnnnvrrnnnvrnnannennannrnnnnnennnnnennnnnernnnnennnnnennnnnennnnnrnnnnnenn 118 Create Display Window and Set up the Trace 119 dB and Linear Magnitude e 119 EI leie D lee 121 Se 5 1 EE 121 Select the View Mode cccssscccsssecesseecesseeceseecesseeceseeecssaeecsseeecssseeesseeesseseessseeesseeeesseesesseaeesseaeessseeeessneaseness 122 5 TRANSIENT CAPTURE AND HAMMER TEGTING ccccccccessceeeeceeseeeeseeeeeeeeseeseeesseesseeesseessseeesseeeseneens 123 Transient el 123 Jee fe Eil 5 ao NE NE 123 Impact Test Analyzer Settings c cccccscccssssecssseecssseeesseeeeseeessseeesseeeessaeeeseaeessseeeesssseessseeessaeesssaeesssnsesssseeeeees 125 CSA Editor Operation for Transient Capture 126 CoCo Hardware Operation for Transient Capture 127 Sj OG A a 9 gt 0 i ne ee ee E A 127 Analysis Parameters Window Tvpe e 127 ee Tea Le 128 Save Averaged DAA unne stemesnitdmsdsmesnide 131 6 BUILT IN DIGITAL INTEGRATION AND EITERING 132 Introduction to Digital Integration rrrnvvrrnnrvennnrvrrnnvvrnnnvrrrnnvvrnnnvnrnnnnnnnnnnnrnnnnernnnnennnnnrnnnnnennnnnennnnnennnnnennnnnennnnne 132 S650 Considerato ES iar e anain 133 Calculation Errors in Digital Integration
160. roject uses If you allocate too many computational tasks in the following steps then the sampling rate may have to be reduced The Editor will give you chances to make the changes later if necessary It is best to choose the lowest sampling rate that you know that you will need for your application to conserve DSP resources After the CSA Editor Wizard is finished you may apply various data conditioning modules to the time streams For details about how to apply the data conditioning modules refer to the User s Manual of CSA Editor Then go to Acquisition Mode follow the instructions in the Manuals to set the trigger source candidate Acquisition Mode Block Size and Overlap Size Data Condboring Acquis ian Mode Signs Atum Signal Sarrar i hpu Tre Svea Trigger and Bock Acgquetor ATR sition Mode a pt ch Set om Trigger Source Carddate ef om Trigger Source Cardosses Te po A rth ve an Trigger Source Catddate m Figure 102 CSA Editor Wizard Acquisition Mode selection Select the Signals to Compute The Signal Analysis tab in the CSA Editor is the area to enable which signals will be computed You can change all the names of the signals By default the following signal name conventions are used CHn the native raw data in the form of a time stream of nth input channel BLOCK chn the block captured signal of the nth input channel APS x the auto power spectrum of time stream x CPS y x the cross power spectrum of excitation x an
161. rporation www go ci com Safety Information Read First The Cl CoCo 80 Handheld Data Acquisition System complies with EN 61326 1997 A1 1998 A2 2001 EN61000 3 2 2000 amp EN61000 3 3 1995 A1 2001 Use the CoCo 80 and its accessories only as specified in the User s Manual Otherwise the protection provided by the Instrument and its accessories might be impaired Condensation may form on the circuit boards when the device is moved from a cold environment to a warm one In these situations always wait until the device warms up to room temperature and is completely dry before turning it on The acclimatization period should take about 2 hours For the most accurate measurements a warm up phase of 20 min is recommended 5 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL The devices have been designed for use in clean and dry environments It is not to be operated in 1 exceedingly dusty and or wet environments 2 in environments where danger of explosion exists nor 3 in environments containing aggressive chemical agents Lay cables in a manner to avoid hazards tripping and damage A Warning identifies conditions and actions that pose hazard s to the user A Caution identifies conditions and actions that may damage the Instrument To avoid electrical shock or fire 1 Realize that the CoCo 80 is a low voltage measurement instrument 2 Do not apply input voltages above the rating of the Instrument You
162. rrnvrrnnnvrnnnnvennnrvrnnnnvrrnnnvrnnnnvrnnnnvennnnnennnnvennnnnennnnnennnnnennnnnennnnnennnnnenn 133 Bieles Ielwen EN EE 135 ele RRE OM EE 135 T EDM PC SOFTWARE iene 137 The CoCo DSA Mod of RE 140 BELE GE 1 SU SF EE EE NN E 140 EAL I ANAM EE MN MN 140 iv COCO 80 USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Data Re SE ME Rii 141 Ee L e EE GG lg La Ile Misis iana i i etna oceuelalseucniciadeaenetnpenee a a 141 Transfer Data Files to the Host RE 142 Configuring the CoCo 80 Network Settings rrrrrrrrnnvrnnnnvrnnnnvernnnvrnnnnvrnnnnvrnnnnnennnnnennnnnennnnnennnnnennnnnennnnnennnnnenn 142 Configuring the Host PC Network Settings ccccccsccsscecsseecsseesseecseeessaeesseeeseaeessaeessaeesseeessaeesseeessneessaeesaas 145 Connect CoCo 80 to a PC directly using USB chent 145 Connect CoCo 80 to a PC directly using Ethernet via cross overca bie 145 Connect CoCo 80 to a local network using Ethernet rrrrnnvrnnnrvennnrvennnrvennnvvennnrvennnvvennnvvennnvvennnnnennnvnennnnnen 145 Connect CoCo 80 to a local network using wireless SD card rrnnrvrnnnnvvvrnnnnvvennnnvvrnnnnnvernnnnvnrnrnnvnrrrnnnvennnnnnn 146 Network Connection RI eine 146 Diagnosis from the GoG0 80 side EE 146 Diagnosis FOM MO OE e E E E E EE e 147 BEEN FON EN NN NN NN 147 ASAM ODS Open Data Service ccccccccscscceseceseceeescceeescsecesceeensceeesseceensceecasoeeeeseeeessccensseeensceeensceeessceess 147 UPE GI 148 The Binary 58 Univ
163. rrowband Random broadband Transient broadband Li Power RMS Power Energy inear Power S Spectrum Spectrum Spectrum pectrum Spectrum Denei G Sx over ensity ensity i SxSx T Sqrt PSD SxSx TT Averaging Window amplitude correction Window energy correction Select one of the spectrum type EUpk EUpkpk EUrms ve ef EUrms Hz EUrms sqrt Hz EUrms S Hz m Figure 82 Flow chart to determine measurement technique for various signal types The following figures illustrate the results of different measurement techniques on a 1 volt pure sine tone The figures include RMS Peak or Peak Peak value for the amplitude or power value corresponding to its amplitude Notice these readings can only be applied to a periodic signal If you applied these measurement techniques to a signal with random nature the spectrum would not be a meaningful representation of the signal EU bx or EU okpx 91 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL The EU and EUs displays the peak value or peak peak value of a periodic frequency component at a discrete frequency These two spectrum types are suitable for narrowband signals 1 200 1 000 sine wave with 1Vpk displayed in EUpk Hann window applied 0 800 0 600 Mag Vi 0 peak 0 400 0 200 950 000 1000 000 1050 000 1100 000 Frequency Hz m Figure 83 A sine wave is measured with EUpk
164. s that control the data acquisition Rec Stop button only applies to the continuous time streams in the data conditioning phase while the Save button only applies to the captured time buffer and spectral signals in the signal analyzer phase Recording and Save cannot be performed at the same time In the other words when the time streams is being recorded the spectral analysis cannot be saved To save a spectral analysis signal the time recording must first be stopped Re Start soft button re initializes the data conditioning acquisition mode control and spectral analysis It resets the timer of time streams re arm the trigger and reset the average number of spectral analysis Block Size governs the size of transient capture or FFT processing in the signal analyzer phase Block Size has no influence on the length of the time streams in the data conditioning phase Both time streams and block by block signals can be displayed with continuous update Run mode or frozen on the screen Hold mode In the signal display window the F6 software button is assigned to the RUN Hold function Hold means the display and spectral analysis are frozen on the screen Hold does not stop the data conditioning and recording process If data is being recorded and the Hold button is pressed the data will continue to be recorded until the Rec Stop button is pressed again 67 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL The ac
165. so use overlapping No Overlap Overlap is not applied Automatic System determines the best overlap rate 25 Overlap Frames are overlapped by 25 50 Overlap Frames are overlapped by 50 75 Overlap Frames are overlapped by 75 Acquisition Mode Setup This section explains how to set up the acquisition mode and the trigger related parameters First select the Acquisition Mode under the Param Setting then the acquisition mode screen will be shown The soft buttons are assigned with different functions Trigger Trigger se 3 Press F1 to select one of the acquisition modes 71 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Continuous after Trigger Single Shot without Trigger Single Shot with Trigger Manual Arm Trigger Auto Arm Trigger When the Acquisition Mode is not Free Run the Trigger Source Trigger Condition must be defined Press F2 Trigger Source to select one of the time streams as the trigger source These time streams are set as Trigger Source Candidates by the CSA Editor when this CSA project is created on the host PC Trigger Press F3 Trigger Cond to select one of the trigger conditions You can also key in the trigger level s using Editing Level entry chi lt Low Level Falling edge Low Level lt chi lt High Level chi gt High Level OR chi Low Level Edit Low Level Edit High Level Edit Trigger Delay Tri
166. spectrum unit The sine waveform has a 1V amplitude EU rms The EU ms displays the RMS value of a periodic frequency component at a discrete frequency This spectrum type is suitable for narrowband signals 0 800 A sine wave with 0 700 1Vipk displayed in EUs Hann window 0 600 0 500 0 400 Mag V RMS 0 300 0 200 0 700 950 000 1000 000 1050 000 1100 000 Frequency Hz m Figure 84 A sine wave is measured with EUrms spectrum unit The peak reading is 0 707V The sine waveform has a 1V amplitude ELL Power spectrum The EU ms displays the power reading of a periodic frequency component at a discrete frequency This spectrum type is suitable for narrowband signals 92 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Mag NZ RMS 0 500 jw Asine wave with 1Vpk displayed in Elrms Hann window applied 0 400 0 300 U 200 0 100 900 000 950 000 1000 000 1050 000 1100 000 Frequency Hz m Figure 85 A sine wave is measured with EUrms 2 spectrum unit The peak reading is 0 5V The sine waveform has a 1V amplitude EU Hz Power Spectrum Density The EU Hz is the spectrum unit used in power spectrum density PSD calculations The unit is in engineering units squared divided by the equivalent filter bandwidth This provides power normalized to a 1Hz bandwidth This is useful for wideband continuous signals EU Hz really should be written as ELL Hz But proba
167. system changes to a hold condition After the data capture you will be prompted with an Accept Reject dialog box If you accept the new data capture then the block will be included into the average and the system will return to the wait mode If you reject the new data capture the new block will be discarded and the system will return to the wait for trigger mode This mode is the best for applications such as impact hammer testing where you may not have confidence in the signal quality of some of the data blocks Trigger Source Trigger Source defines what signal is used to determine a trigger event Any time stream that is set as trigger source candidate in the CSA can be selected as trigger source on the CoCo 80 If a signal is not identified as a trigger source candidate in the CSA file then the signal will not appear on the list This feature is designed to simplify the user interface and optimize the CoCo 80 computation resources The candidates of Acquisition Mode selection and Trigger Source selection will be defined by the CSA editor The CSA editor will assign some the data streams after the data conditioning as candidates of trigger sources For example in a CSA there are 8 channels if you only select chi and ch2 time streams as candidates of trigger source and then this CSA will only show ch1 and ch2 on the trigger source selection menu You may also define time streams other than native channels as trigger source candidate For examp
168. t evaluation and simulation environments have their own proprietary formats to store data These formats usually are very different from each other regarding the description of the configuration unit under test test sequence test equipment etc as well as the way results are stored database binary files etc The main objectives for a standardization of data access interfaces are to reduce costs and risks within projects and to provide a reliable basis for implementations in the area of data storage and data usage Using standardized interfaces and common structures minimizes the efforts for the system integration within the heterogeneous environments discussed above and makes it much easier to exchange data Because of these benefits the ASAM ODS data format was chosen as the internal format for the CoCo 80 and the EDM software UFF Files The CoCo 80 and EDM Software also support the Universal File format UFF This format was originally developed by the Structural Dynamics Research Corporation SDRC in the late 1960s and early 1970s to facilitate data transfer between computer aided design CAD and computer aided test CAT in order to facilitate computer aided engineering CAE SDRC as part of EDS continues to support and utilize the UF formats as part of their CAE software Currently MIS Noise and Vibration Division supports and continues to develop IDEAS software in the test area that utilizes UF formats The formats were
169. tCo 60 connects to LAN Wirelessly m Figure 140 EDM network connection status screen Select appropriate connection type and follow the online instructions The EDM will provide diagnose information Data Format The data format within the CoCo 80 and the EDM software is the ASAM ODS File format ASAM ODS files have the suffix ATFX EDM also interfaces to other file formats including NI TDM MatLab UFF BUFF and user defined ASCII files ASAM ODS Open Data Service The rapid progress in hardware and software leads to storage of data in many different data base systems as well as under different hardware and or server generations During development and production of complex products a huge mass of data is produced Today data are stored within the automotive industry in a standardized format specified by the ASAM ODS workgroup ASAM stands for Association for Standardization of Automation and Measuring Systems and ODS stands for Open Data Services The CoCo 80 uses the ASAM ODS data format as the internal data format and data is saved by default in this format when it is downloaded from the device to a PC 147 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL The ASAM ODS standard has the fundamental quality of storing data with an architecture independent method This leads to great advantages when exchanging data between different sources and possible prospective customers Many systems in tes
170. tem of Selection integration or differentiation select appropriate item The example shows Double Integration to Displacement is selected Select the appropriate engineering units for displacement The example shows displacement units of millimeters Set the Sensor Sensitivity For channel 1 Measurement Quantity Acceleration Sensor Engineering Unit gri ensor Sensitivity 50 mylign Select integration or differentiation Pbl Integration to Displacement EU after integration or differentiation m Figure 134 Sensor sensitivity window with double integration and units With this setup the accelerometer is set to measure g while the displacement is using millimeter as the output unit The sensor sensitivity 50mV g transforms the input voltage into g appropriately To enable or set the high pass filter simply go to the channel table and high light the column of Hi Pass Fltr and press Enter button Each channel can have its independent cutoff filter values 136 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL IEPE Loop Power iHz 100 mw lg IEPE Loop Power 100 mv lg AC Differential Trans Save 7 EDM PC SOFTWARE This section briefly describes the Engineering Data Management EDM software that is used to download data from the CoCo 80 to a PC view analyze and export the data For details about EDM software install
171. testing schedule requires an extra step This is designed to ensure the test schedule does not start inadvertently To activate the testing schedule go to the main signal display window and press the Display button for more then 3 seconds then release it This will activate the test schedule After the test schedule is activated all the buttons except the power button F5 and F6 will not deactivate because the test is in the automatic mode To exit the automated schedule press F6 the exit button To redo the schedule press F5 Using schedule smartly allows the instrument to divide the total measurement into multiple files It is easier to retrieve and analyze The picture below shows a typical schedule with loop end loop functions It allows the instrument records 1 hour stop run for 1 min and repeats this recording process 1000 times When the schedule is activated the schedule status will be displayed during the run time 28 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Use following formula to calculate the total time duration that you can record Total Installed Flash Memory in Bytes Total Channel Enabled Recording Time in Seconds Sampling Rate 8 Bytes 1 2 Or Recording Time in Seconds Total Installed Memory in Bytes Total Channel Enabled Sampling Rate 8 Bytes 1 2 For example if you enabled 6 channels the sampling rate is 100 Hz with 4GB memory installed
172. the up and down arrow buttons to select from the scroll menu and press the Enter button to accept the setting Sampling rate is a global setting that applies any loaded CSA Input Channels is used to set the sensitivity input mode and label for the hardware input channels To edit these parameters use the arrow buttons to select the parameter and press the Enter button Input Channels is a global setting that applies any loaded CSA When the user selects Inout Channels menu item the channel status screen will be shown It displays the peak magnitude of each channel over a certain period of time Notice that the vertical scaling of the bars is in logarithmic The log scaling will help the user see both large and small signals Thanks to the high dynamic technology implemented in the CoCo as long as the signals are within the full range the measurement will be reasonably accurate However if the signals are above the full range overload will occur and the instrument will flash to warn the user 23 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Input Channel Table Sensitivit y Inp it Mode Diferential Single End DC Differenial AC Single End AC Dilferentia m Figure 19 Left Input status Right Inout Channel Table Sensitivity is used to set the physical quantity units and sensitivity of the input channel Use the arrow buttons to select the parameter and press the Enter button to sele
173. this channel is designated the other channels will be set as response channels automatically For cross channel signals the default signal names always follow the convention y x where y measures the system response and x the excitation All signals can be edited in the CSA Editor Editing an Arbitrary Waveform The CoCo output channel can generate an arbitrary waveform which can be programmed on the EDM software To create an arbitrary waveform you must edit it in the EDM software and then upload it to the CoCo hardware The waveforms can either be imported from a text file or drawn by hand In the EDM software right click on Arbitrary Waveform Files to open the Arbitrary Waveform Editor 113 COCO 80 BASIC DSA USER MANUAL CRYSTAL Instruments COCO 80 USER S MANUAL D Home G w jAnalyss Repon zia gt da Expio e Canned Search af Favor Device Operators device Pile View Fo Customee A Cate Fies Name K m Figure 104 Edit arbitrary waveform in EDM software To draw a waveform by hand click and hold the mouse button then draw the desired Arbitrary waveform on the top half of the window IE TN I m Figure 105 Arbitrary waveform editor in EDM software After the waveform is completed the value of each point can be changed by entering the value in the box New Arb Wave creates a blank pane for another arbitrary waveform Copy and Paste let you copy the current waveform into a
174. tream Recording Setup Signal Snapshot Save Setup Limit Check Alarm Events include Beep Screen Flashing Event Log into Testing Log Send Message to Host PC Save Signals Restart Soft Button is used to reset the relative time base of the time streams and also reset the averaging and triggering if these features are used in the current CSA project The Restart will be shown as Control button in octave analysis order tracking swept sine or other advanced software functions Restart or Control is used to control the running status without re initializing the project and test Auto Scale ZOOM Move Soft Button controls the vertical scaling of the trace Auto applies an automatic vertical scaling so that the scale is continuously adjusted to fill the trace ZOOM scale turns off the automatic scaling and uses the current scale regardless of the magnitude of the signals When in the ZOOM scaling mode the four arrow buttons are used for the purpose of reducing or expanding Pressing the SHIFT button will switch from ZOOM to Move or Move to ZOOM When in the Move mode the four arrow buttons are used for the purpose of repositioning the window The following diagram further explains the changes in the three different mode of using the navigation buttons 31 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Auto Scaling Left right Up Down Move position m Figure 26 Trace navigation buttons Cursor Soft Bu
175. tton adds a vertical cursor to the trace Use the right and left arrow keys to move the cursor The signal values are listed to the right for all signals in a trace Press the Cursor button again to remove the cursor from the trace add Cursor S2 Add Cursor v1 Add Cursor 2 Remove All Cursors Peak Mark Calculate RMS m Figure 27 Cursors can be added to a trace After the cursor is added you will see a menu item is added to the Cursor Setup menu Move Cursor Display Location If you select it you will be able to move around the square area of displaying the cursor value by using the four navigation buttons This function is helpful if you feel the cursor display box is not in the right location Pressing Enter button will fix the cursor display area 32 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Remove Cursor al Add Cursor 42 Add Cursor Yi Add Cursor Y2 Remove All Cursors Peak Mark m Figure 28 Cursor setup To search for the peak using cursor simply press the upper arrow button when a cursor is enabled The cursor will automatically search a peak of the signal in 10 of the horizontal axis area Two vertical cursors two horizontal cursors and a peak mark can be applied To calculate RMS within a frequency band for auto spectral signals select Calculate RMS menu item 33 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL A
176. tual Data Conditioning and Signal Analysis function processing are defined by a special technology CSA as described in the following section Acquisition Mode This section describes Acquisition Mode which acts as a trigger to capture block by block data from continuous time streams The instrument separates the data processing into three stages data conditioning acquisition mode and signal analysis Acquisition Mode controls how the continuous time stream data is captured for block by block processing Acquisition Mode control is applied after data conditioning and before the signal analysis stage If a CSA does not include a block capture function then Acquisition Mode will not be used Data conditioning Signal analysis m Figure 66 Data processing is separated into three stages Note in the description below sometimes when we say capture a block of data it really means that multiple blocks of data are captured from their own time streams These blocks are all accurately time synchronized Acquisition Mode Acquisition Mode defines how the device responds when a trigger event is detected and includes the following options Free Run displays block data acquired from the time stream as fast as possible or at the overlap rate by the user Free Run is commonly used to analyze the random or irregular signals Continuous after Trigger waits until a trigger event is detected After the first trigger event av
177. use it and send it in for repair 6 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL 2 QUICK START This Quick Start section is intended to give a brief introduction to the most basic use of the CoCo 80 system By following the instructions you will learn how to do the following 1 Record Time Streams with CoCo 80 2 Install the EDM software to your host PC 3 Download and view the data on host the PC After completing the Quick Start tutorial you should read the following sections for a more comprehensive description of the system Recording Time Streams with CoCo 80 1 Remove the CoCo 80 unit from the shipping packaging 2 Connect the wall mount power adaptor to the 110V 220V power outlet 3 Connect the wall mount power adaptor to the CoCo 80 if battery is not charged 4 Push the power button on CoCo 80 wait for about 30 seconds until the Welcome screen is displayed 5 Use the Up or Down arrow buttons to select one of the CSA project files to run 6 In the signal display screen press F2 Param and select Time Stream Recording Setup to define data streams for recording To enable the recording for any signal first use the up down arrow navigation buttons to move to the signal then press the Enter button to select or de select 7 Push the Rec Stop button to record the signals After a few seconds push the Rec Stop button again to stop the recording 8 Push the File button then the F
178. use you have not accept the time signal yet Now you may do one of two things Accept or Reject If you press the Accept button the acquired block signals will be passed to the signal analysis stage usually windowing FFT and spectral analysis Then you can continue to the Next frame of capture After you press the Next key the system will go back to waiting in trigger mode If you press Reject then the captured time signals will be discarded and will not be sent to signal analysis stage After the Reject action the system goes back to waiting in trigger mode The number showed on the top status bar N indicates the number of the frames of the time captures that have been accepted and averaged into the spectra After you press the Hide key the small from window will disappear Press Enter to show this window again During trigger operation you can switch the main display window to any trace This can be helpful to view the time stream selected as the trigger source to tune the level and slope settings 75 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL Save Data to flash Memory or SD memory card Introduction Ranging from different applications several ways are devised to save the signals that are being measured The media of storage can be either internal flash memory or SD memory card Save Long Time Waveform Signal the time streams can be saved either automatically by a preset sch
179. uttons two virtual keypads scrolling and make selections in any combo box ZOOM in scaling ZOOM out scaling the graph To ZOOM in the graph hold the left button of the mouse and drag to the area that you intent then release the left button To ZOOM out the graph to the previous scaling stage double click on the graph SD Card Interface The MMC SD Card interface is designed to be used for multiple purposes mainly the high density memory card The official information about the MMC SD card can be found on the official site http www sdcard org 51 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL The user can copy the recorded signal files from the internal flash memory to SD memory card or directly record the time stream data to SD memory card Audio Devices CoCo 80 has the following built in audio devices e 3 5mm stereo jack connector for an earphone e Built in speaker e Built in microphone The earphone and speaker are used to generate status sounds that provide audio feedback to the use such as e AC adapter is connected e AC adapter power was disconnected e System boot up successful e System boot up failure Battery There are two batteries inside the CoCo 80 device the clock battery and the main battery The clock battery is only used maintain power to the internal clock It is located inside the hardware and should be replaced when necessary by an authorized Cl service center and should not
180. versal file format The first and last record are start stop records and are always 1 in the first six columns right 148 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL justified Fortran I6 field with 1 in the field The second record Identifier Record always contains the universal file format number in the first 6 columns right justified This gives a file structure as follows where b represent a blank character bbbb 1 bbbb58 bbbb 1 The Binary 58 universal file format was originally developed by the UC SDRL in order to eliminate the need to compress the UFF 58 records and to reduce the time required to load the UFF 58 data records The Binary 58 universal file format yields files that are comparable to compressed files approximately 3 to 4 times smaller than the equivalent UFF 58 file The Binary 58 universal file format loads approximately 30 to 40 times faster than the equivalent UFF 58 file depending upon the computing environment This new format was submitted to SDRC and subsequently adopted as a supported format The Binary 58 universal file format uses the same ASCII records at the start of each data file as the ASCII dataset 58 but beginning with record 12 the data is stored in binary form rather than the specified ASCII format The identifier record has the same 58 identifier in the first six columns right justified but has additional information in the rest of the 80 character record t
181. vertically move the display range down depending on SHIFT position Move the focus left In display window scaling reduce the horizontal range In display window scaling horizontally move the display range left depending on SHIFT position Left arrow Move the focus right In display window scaling increase the horizontal range In display window scaling horizontally move the display range right depending on SHIFT position Right arrow Confirm accept Escape Cancel or go back to the previous settings applies to the scaling of display window cursor position and other operations Change to analysis screen Change to the main signal display screen Change to the main setup screen Setup Change to the main file view screen File Start or stop the time domain data recording designated by the CSA ed Rec Stop project Save the signals that are designated by the CSA project _ Save Ge Open the input channel setup page to configure the sensors or input Sensors channels Recall or review the last saved signals Recall Recall Next Tre Switch to the next display trace Next Trc 11 COCO 80 BASIC DSA USER MANUAL CRYSTAL N struments 6060 80 USER S MANUAL in Open the View mode menu to set up the view mode for the active trace View Mode View Mode rq On Or Turn trigger on or off When trigger is OFF it runs in free run mode Trg On Off User This button will lead the
182. will depend on the accuracy of the meter System Calibration rst uses the meter to calibrate the output signal channel then the system will automatically calibrate the input channels by using output signal Each input channel is installed with relay intemally When input channel is calibrated no external connection is necessary After all input channels are automatically calibrated you need to use the voltage meter to validate the calibration results IF validation is passed system will be fully calibrated Press the Pec button ko pror eed ko the Following step m Figure 40 System Calibration Screen Calibration results can be viewed on the CoCo 80 by pressing View Report in the above screen 10 of 10 Calibration Report Ch Offset Gan Result Calibrated at Qutp 0 00 fc Pass Jan 16 2008 CH 0 00 Dn Pass See ee Freen bm JUL UUs Dass o oo loo Pass o oo 0 0 Pass FLUKE 45 CHE 0 00 0 0 Pass c j sn B966076 SHE 10 00 0 09 Dass 0 00 DK Pass CHS 1009 0 0 Pass m Figure 41 Calibration Report Display Preference changes to the Signal Display Preferences that are applied to all traces 40 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL 3 SLO H EEE TTT Te A Sho rTreErere Display Preferences b Horizontal Axis of Spectra Linear b Spectrum Type and Scaling EUrms 12 m Figure 42 Display Preference screen Tim
183. zed reseller and does not apply to fuses disposable batteries or to any product which in CI s opinion has been misused altered neglected or damaged by accident or abnormal conditions of operation or handling CI warrants that software will operate substantially in accordance with its functional specifications for one year and that it has been properly recorded on non defective media Cl does not warrant that software will be error free or operate without interruption 4 COCO 80 BASIC DSA USER MANUAL CRYSTAL instruments COCO 80 USER S MANUAL CI authorized resellers shall extend this warranty on new and unused products to end user customers only but have no authority to extend a greater or different warranty on behalf of CI Warranty support is available if the product is purchased through a Cl authorized sales outlet or the Buyer has paid the applicable international price Cl reserves the right to invoice the Buyer for importation costs of repair replacement parts when product purchased in one country is submitted for repair in another country Cl s warranty obligation is limited at Cl s option to refund of the purchase price free of charge repair or replacement of a defective product which is returned to a Cl authorized service center within the warranty period To obtain warranty service contact your nearest Cl authorized service center or send the product with a description of the difficulty postage and insurance prepaid FOB Dest

CoCo-80 Basic DSA User`s Manual - C

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