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1. 1705 TRUE RMS PROGRAMMABLE MULTIMETER All inputs 1KV Cat T 600V Cat TE max to 4 A dB Hol Null FUNCTION R d old u N un NS S rif l r1 mV ac Copy rdg A h wac l l LI AUTO THod QNu Addr Baud ff a bu m um Shift Print Manuallog Local EDIT Cance oO 0 g q g 0 v Esc Cir co A Rel Logger Clr fF iA Vde Vac Q Hz Range m DUAL DISFLAY Chang mae DUAL MEASUREMENT Jigit A U yf FUSED Cal Operate Salect DOMUS 10A ma e 2 max d Idc Tac 4 3 yF iam Li e fc SN FUSED uer H Digit 10A e THURLE Y THANEAR INSTRUMENTS ond Functions Autoony ac dc WA DM Keyboard Organisation The keys can be considered in two groups The two rows of keys in the lower half of the keyboard directly select the functions and ranges of both the primary and secondary displays When pressed alone the function keys select the function of the primary display cancel any secondary function and set autorange the operating range is shown in the secondary display Pressing Select 2nd followed by a function key selects the function of the secondary display this is explained fully in the Dual Measurement Mode section which also details which combinations of functions can be used Auto Man and Range Up Range Down keys are additionally used when editing numbers for some of the modifier functions see the N
2. 500mA F 250V HBC x O O 3 O O al O QL 10A F 250V HBC Reassemble in the reverse order o ET 28 Remote Operation Introduction RS232 remote control is standard and can be used either in a conventional one to one mode or in addressable mode as part of an ARC Addressable RS232 Chain system RS232 can only be used when the meter is powered from an AC supply GPIB IEEE 488 remote control is available in addition to RS232 on a mains only version it is not a retrofittable option The ARC Addressable RS232 Chain interface allows a collection of instruments up to a maximum of 32 to be connected to a single serial interface on a PC or other computer system Each instrument may then be uniquely addressed so that commands for that instrument may be sent and ignored by all other instruments connected to the interface Additionally ARC instruments may be used on a simple RS232 interface in non addressable mode without modification Available as an option is the ARCTALK software package for IBM compatible PCs At the simplest level ARCTALK provides realtime direct control of instruments on the ARC bus from the PC s keyboard However it can be used more effectively to create complete programs within which several instruments can be set up and or measurements read back responses can be captured in a response file for l
3. 3BH A PROGRAM MESSAGE UNIT is any of the commands in the REMOTE COMMANDS section PROGRAM MESSAGES are separated by a PROGRAM MESSAGE TERMINATOR which is the new line character OAH Responses from the instrument to the controller are sent as RESPONSE MESSAGES A RESPONSE MESSAGE consists of one RESPONSE MESSAGE UNIT followed by a RESPONSE MESSAGE TERMINATOR gt which is the carriage return character followed by the new line character ODH OAH Each query produces a specific lt RESPONSE MESSAGE gt which is listed along with the command in the REMOTE COMMANDS section WHITE SPACE is ignored except in command identifiers e g C LS is not equivalent to CLS lt WHITE SPACE gt is defined as character codes OOH to 20H inclusive with the exception of the codes specified as ARC interface commands The high bit of all characters is ignored The commands are case insensitive The commands are case insensitive GPIB Remote Command Formats Commands are sent as PROGRAM MESSAGES by the controller Each message consists of zero or more PROGRAM MESSAGE UNIT elements separated by PROGRAM MESSAGE UNIT SEPARATOR elements PROGRAM MESSAGES are separated by PROGRAM MESSAGE TERMINATOR elements A PROGRAM MESSAGE TERMINATOR is the new line character NL OAH A PROGRAM MESSAGE UNIT SEPARATOR is the semi colon character 3BH A PROGRAM MESSAGE UNIT is any of the co
4. IAC2 lt string gt Sets the secondary display to dc Amps and optionally selects the 10A range if no range is specified the display defaults to mA autorange The following strings can be used lt 1MA gt lt 100MA gt lt 10A gt If the main display is set to dc Amps the secondary range will be the same as the main display range FREQ2 Sets the secondary display to frequency autoranging Vac or lac must first have been selected in the main display First Level Modifier Commands NULL Nulls the main display and sets it to manual i e the current range is held the un nulled reading will be shown in the secondary display if the meter is not in dual measurement mode except for capacitance NULLOFF Cancels Null operation HOLD Holds the value in the main display The normal updated reading will be shown in the secondary display if the meter is not in dual measurement mode except for capacitance 37 HOLD OFF Cancels Hold mode DB lt string gt Sets the main display to show the dB value of the Vac measurement which must have first been selected in the main display and optionally sets the reference impedance if no impedance is specified the existing value is used The following lt strings gt can be used to set the impedance lt 50 gt lt 75 gt lt 93 gt lt 110 gt lt 124 gt lt 125 gt lt 135 gt lt 150 gt gt 250 gt lt 300 gt lt 500 gt lt 600 gt lt 800 gt lt 900 g
5. Sets the main display to ac Volts and optionally sets the range if no range is specified the display defaults to autorange The following lt strings gt can be used to set the range lt 100MV gt lt 1000MV gt lt 10V gt lt 100V gt lt 750V gt 35 VACDC lt string gt Sets the main display to ac dc Volts and optionally sets the range if no range is specified the display defaults to autorange The following lt strings gt can be used to set the range lt 100MV gt lt 1000MV gt lt 10V gt lt 100V gt lt 750V gt IDC lt string gt Sets the main display to dc Amps and optionally sets the range if no range is specified the display defaults to mA autorange The following lt strings gt can be used to set the range lt 1MA gt lt 100MA gt lt 10A gt IAC lt string gt Sets the main display to ac Amps and optionally sets the range if no range is specified the display defaults to mA autorange The following lt strings gt can be used to set the range lt 1MA gt lt 100MA gt lt 10A gt IACDC lt string gt Sets the main display to actdc Amps and optionally sets the range if no range is specified the display defaults to autorange The following lt strings gt can be used to set the range lt 1MA gt lt 100MA gt lt 10A gt OHMS lt string gt Sets the main display to Ohms and optionally sets the range if no range is specified the display defaults to autorange The follo
6. The interface is fully isolated from the measurement system and the GPIB signal grounds are connected to the safety ground The pin connections are as specified in IEEE std 488 1 1987 The implemented subsets are SH1 AH1 T8 L4 SRO RL2 PPO DC1 DTO CO E2 The address is selectable from the front panel Switching On Power Switch The multimeter is switched on and off with alternate presses of the Operate key this key only switches the DC power to the measurement circuits It does not switch the AC power when this is connected which means that the isolated RS232 and GPIB circuits continue to be powered and rechargeable cells if fitted continue to be charged When the instrument is not in use and if battery recharging is not required disconnect from the AC supply If the AC supply is removed whilst the meter is switched on one of two things will happen If the meter had been switched on with the Operate key after connection to AC power the meter will automatically power off if continued operation from batteries is required it will be necessary to switch the instrument back on again In this way the accidental exhaustion of batteries is avoided when AC power is switched off e g when a whole bench of equipment is switched off from a master switch However if the meter had been switched on and run from batteries before the AC power was connected it will continue to run when the AC power is later removed In this mode the batte
7. 8 and 9 are additionally used when the instrument is connected to the ARC interface Using a simple cable assembly a daisy chain connection system between any number of instruments up to the maximum of 32 can be made as shown below CONTROLLER INSTRUMENT gear Meee 1 The daisy chain consists of the transmit data TXD receive date RXD and signal ground lines only There are no control handshake lines This makes XON XOFF protocol essential and allows the inter connection between instruments to contain just 3 wires The wiring of the adaptor cable is shown below TO NEXT INSTRUMENT 9 WAY D S WAY D FEMALE MALE DCD 1 0 3 4 O41 RX 2 Of m O TX TX m 3 9 dL 3 m RX DTR A 4 0 4 O4 GND SO p QO5 GND DSR 6 O _ Os RTS 9 7 0 O7 CTS 8 os RI 90 X Os LINKS TO CONTROLLER NES OTS CHAIN S OOOOOOOOO swrD 423 45 6 7 8 89 MALE AN INSTRUMENT i j ON THE CHAIN TX RX TXIN RXOUT All instruments on the interface must be set to the same baud rate and all must be powered on otherwise instruments further down the daisy chain will not receive any data or commands 30 The ARC standard for the other interface parameters is as follows Start bits 1 Data bits 8 Parity None Stop bits 1 In this instrument as wi
8. Cautions To ensure continued compliance with the EMC directive the following precautions should be observed a only use screened cables and connectors to connect between the multimeter s RS232 interface and other equipment b after opening the case for any reason ensure that all signal and ground connections are remade correctly before replacing the cover Always ensure all case screws are correctly refitted and tightened c In the event of part replacement becoming necessary only use components of an identical type see the Service Manual Installation Mains Operating Voltage Check that the instrument operating voltage marked on the rear panel is suitable for the local supply Should it be necessary to change the operating voltage proceed as follows 1 Disconnect the instrument from all voltage sources 2 Unclip the front bezel by gently pulling the centre of each long edge up and forward The case halves are held together by 4 plastic push rivets Use the blade of a small screwdriver in the slot beside each rivet to first ease out the rivet head and then fully remove the rivet body Separate the case halves Visit www tti test com for further details 3 Change the transformer connections following the diagrams below BLUE BROWN BLUE BROWN 230V 115V 4 Reassemble in the reverse order 5 To comply with safety standard requirements the operating voltage marked on the rear panel must be changed to clearly sho
9. Mode control code 02H SAM must be sent This will then enable all instruments connected to the ARC bus to respond to all interface control codes To return to Non Addressable mode the Lock Non Addressable mode control code must be sent which will disable addressable mode until the instruments are powered off Before an instrument is sent a command it must be addressed to listen by sending the Listen Address control code 12H LAD followed by a single character which has the lower 5 bits corresponding to the unique address of the required instrument e g the codes A Z or a z give the addresses 1 26 inclusive while is address 0 and so on Once addressed to listen the instrument will read and act upon any commands sent until the listen mode is cancelled Because of the asynchronous nature of the interface it is necessary for the controller to be informed that an instrument has accepted the listen address sequence and is ready to receive commands The controller will therefore wait for code 06H ACK before sending any commands The addressed instrument will provide this ACK The controller should time out and try again if no ACK is received within 5 seconds Listen mode will be cancelled by any of the following interface control codes being received 12H LAD Listen Address followed by an address not belonging to this instrument 14H TAD Talk Address for any instrument 03H UNA Universal Unaddress control code 04H LNA Lock Non Addressable
10. 120 e 1 are all accepted as the number 12 Any number when received is converted to the required precision consistent with its use then rounded up to obtain the value for the command If the number is too large for the selected function then the value is set to 99999 on the highest range for that function General Commands IDN Returns the instrument identification in the form NAME MODEL 0 VERSION where NAME is the manufacturer s name MODEL defines the instrument type and VERSION is the revision level of the installed software READ 34 Returns the next reading from the main display immediately after the command has been parsed The syntax of the response is ASCII data rmt where ASCII data is a 18 character string divided into 10 character plus 8 character fields The first field is the measurement value and consists of the following Digit 1 space for positive values or a minus sign 2t a 5 digit number plus decimal point in the format of the range selected for the measurement 8 10 the exponent in the form e00 e 3 e03 etc i e engineering units An overload reading i e gt 12000 counts is returned as OVLOAD in place of the 5 digits plus point a calculation overflow relevant to some function results is returned as OVFLOW In both cases a minus sign can also be shown to indicate negative overload and overflow respectively The second field is the unit
11. Complies with EN61010 1 Complies with EN61326 260 W x 88 H x 235 D mm excl handle and feet 2 0kg EC Declaration of Conformity We Thurlby Thandar Instruments Ltd Glebe Road Huntingdon Cambridgeshire PE29 7DR England declare that the Model 1705 True RMS Programmable Multimeter and Model 1705GP True RMS Programmable Multimeter with GPIB meet the intent of the EMC Directive 89 336 EEC and the Low Voltage Directive 73 23 EEC Compliance was demonstrated by conformance to the following specifications which have been listed in the Official Journal of the European Communities EMC Emissions a EN61326 1998 Radiated Class B b EN61326 1998 Conducted Class B c EN61326 1998 Harmonics referring to EN61000 3 2 2000 Immunity EN61326 1998 Immunity Table 1 Performance B referring to a EN61000 4 2 1995 Electrostatic Discharge b EN61000 4 3 1997 Electromagnetic Field c EN61000 4 11 1994 Voltage Interrupt d EN61000 4 4 1995 Fast Transient e EN61000 4 5 1995 Surge f EN61000 4 6 1996 Conducted RF Safety Multimeter EN61010 1 Installation Category measurements to 1000V Installation Category Il measurements to 600V Pollution Degree 1 Probes IEC1010 2 031 Rated to 1000V Installation Category III Chae oa i CHRIS WILDING TECHNICAL DIRECTOR 2 July 2004 Safety This multimeter is a Safety Class instrument according to IEC classification and has been designed to meet the requirements o
12. be set from 1 second to 9999 seconds setting the period to 0000 turns the internal timer off The Manual Log key remote contact closure at the RS232 input and RS232 remote commands are all logically OR ed with the internal timer Thus to use any of these means of triggering the logger the internal timer should be set to 0000 this is the default value and can most easily be set by pressing Clr during edit To set the logger to be triggered by remote contact closure the internal timer period must be set to 0000 see above and the RS232 interface must be configured for remote triggering To do this press Shift then Baud the shifted function of Run the main display changes to show bAUd and the secondary display shows the current setting Use the Range Up Range Down keys to step through the choices until triG shows in the display exit the selection at this point by pressing Baud again or Esc The RS232 interface is now configured to act as a remote trigger for the data logger by contact closure between pins 2 and 3 do not apply an external voltage to these pins or damage to the instrument may result Reselect the logger using the FUNCTION key The logger is run by pressing the Run key and stopped by the Cancel key a short beep is sounded every time a measurement is stored The logger starts from location 1 if the store is empty and from the next empty store location on subsequent occasions when the logger reaches 100 measurements it ignores
13. first field is the reading number consisting of 3 digits followed by three spaces The following two fields each of 8 digits contain the measurement value and measurement units respectively in exactly the same format as the response to the standard READ command see that command section for details TRIG With the data logger on a reading will be stored each time the TRIG command is set Since the remote command is OR ed with the internal timer either both can be run together or the internal timer can be disabled by setting the interval to 0000 seconds CANCEL Stops the logger running LOGCLEAR Cancels the logger function if it is running and clears the results from the logger memory Calibration Commands SETCAL Used for calibration only refer to Service Manual STEPCAL Used for calibration only refer to Service Manual REJ50 Optimizes analogue to digital converter for 50Hz rejection see Calibration section of manual for further explanation REJ60 Optimizes analogue to digital converter for 60Hz rejection see Calibration section of manual for further explanation 40 Default Settings The meter is put into the following default condition as a result of a system reset hold Cancel down at switch on or by the RST remote command Function set to DC Volts single measurement mode Autoranging mode set All first level modifiers cancelled including Ohms Null All second level modifiers cancelled Ax b factors
14. further settings PC 02 and Trig are listed with the Baud rate These are for when the RS232 interface is used with a parallel printer or remote data logger trigger respectively refer to the Printing and Data Logger sections for details Remote Local Operation At power on the instrument will be in the local state in this state all keyboard operations are possible When the instrument is addressed to listen and a command is received the remote state will be entered and the REM symbol will show in the display In this state the keyboard is 29 locked out and only remote commands will be processed The instrument may be returned to the local state by pressing the Local key however the effect of this action will remain only until the instrument is addressed again or receives another character from the ARC interface when the remote state will once again be entered ARC Interface ARC Interface Connections The 9 way D type serial interface connector is located on the instrument rear panel The pin connections are as shown below Pin Name Description 1 Power to optional PC 02 2 TXD Transmitted data from instrument 3 RXD Received data to instrument 4 No internal connection 5 GND Signal ground 6 No internal connection 7 RXD2 Secondary received data see diagram 8 TXD2 Secondary transmitted data see diagram GND Signal ground Pins 2 3 and 5 may be used as a conventional RS232 interface with XON XOFF handshaking Pins 7
15. further triggers Pressing Cancel while the logger is running will stop the logger and exit the function without losing the data Reviewing Results and Clearing the Logger The logger results can be reviewed at any time by pressing Shift Logger Rcl the shifted function of EDIT if the Logger is running this action will stop it The logged result is shown in the main display with the reading number in the secondary display the LOGGER annunciator is shown All valid store locations can be inspected by scrolling through them with the Range Up and Range Down keys Empty store locations cannot be selected and the scrolling wraps around from highest valid location to location 1 when ranging up and vice versa when ranging down Press Esc to exit logger recall mode To clear the logger press Shift Clr Logger the shifted function of Cancel if the loggers is running this action will stop it The secondary display will briefly show the LOGGER symbol and none in the secondary display to show that it has been cleared if the logger is reviewed when all locations are empty it will similarly show none briefly in the secondary display To print the logger results see next section 25 Printing The current display reading or the logger results can be output via the RS232 port Connect the device to the RS232 port Press Shift then Baud the shifted function of Run and use the Range Up Range Down keys to select an appropriate
16. indication and will be one of the following the field starts with a space and additional spaces are sent at the end of the field to always make it 8 characters long V DC VAC V AC DC ADC AAC AAC DC Hz Ohms F V for diode test dB W VA Examples 101 23e 3 V DC 101 23mv 10 001e00 V DC 10 001V 00 123e00 V AC DC 0 123V 100 01e03 Hz 100 01kHz 01 010e 6 F 1 01pF READ2 Returns the next reading from the secondary display immediately after the command has been parsed The syntax is as for READ described above If the secondary display is currently showing the range of the main display the response will be RANGE EVERY Sends every reading from the main display until stopped by STOP or any other command The syntax of each reading is ASCII data gt lt rmt gt where ASCII data is an 18 character string divided into two fields value followed by units exactly as for the standard READ response see that command section for details STOP Cancels the EVERY command RST Resets the meter to the factory default settings except for the Address and Baud rate of the RS232 interface itself Main Display Commands VDC lt string gt Sets the main display to dc Volts and optionally sets the range if no range is specified the display defaults to autorange The following lt strings gt can be used to set the range lt 100MV gt lt 1000MV gt lt 10V gt lt 100V gt lt 1000V gt VAC lt string gt
17. mode control code 18H UDC Universal Device Clear Before a response can be read from an instrument it must be addressed to talk by sending the Talk Address control code 14H TAD followed by a single character which has the lower 5 bits corresponding to the unique address of the required instrument as for the listen address control 31 code above Once addressed to talk the instrument will send the response message it has available if any and then exit the talk addressed state Only one response message will be sent each time the instrument is addressed to talk Talk mode will be cancelled by any of the following interface control codes being received 12H LAD Listen Address for any instrument 14H TAD Talk Address followed by an address not belonging to this instrument 03H UNA Universal Unaddress control code 04H LNA Lock Non Addressable mode control code 18H UDC Universal Device Clear Talk mode will also be cancelled when the instrument has completed sending a response message or has nothing to say The interface code OAH LF is the Universal Command and response Terminator UCT it must be the last code sent in all commands and will be the last code sent in all responses The interface code ODH CR may be used as required to aid the formatting of commands it will be ignored by all instruments Most instruments will terminate responses with CR followed by LF The interface code 13H XOFF may be sent at any time by a list
18. set to A 1 0000 and b 00000 Limits set to 0 0000 Delta reference set to 10000 dB reference impedance set to 6000 Watts reference impedance set to 50 Set data logger off and timer to 0000 seconds but preserve logger store contents Bus address set to 1 not by RST Baud rate set to 9600 not by RST Calibration constants and the 50 60Hz rejection setting are unaffected by a system reset TEST EQUIPMENT RISK ASSESSMENT Recommendation from the U K Health and Safety Executive Users of this equipment and or their employers are reminded that Health and Safety Legislation require them to carry out valid risk assessments of all electrical work so as to identify potential sources of electrical danger and risk of electrical injury such as from inadvertent short circuits Where the assessments show that the risk is significant then the use of fused test leads constructed in accordance with the HSE guidance note GS38 Electrical Test Equipment for use by electricians should be used 41 TITiz Thurlby Thandar Instruments Ltd Glebe Road Huntingdon Cambridgeshire PE29 7DR England Telephone 44 0 1480 412451 Fax 44 0 1480 450409 e mail sales tti test com International website www tti test com UK website www tti co uk Book Part No 48581 1160 Issue 7
19. than 1096 of range Capacitance for all other Vac and lac ranges Range Accuracy Resolution et meoo ru 2 x 5 dig a IF ldnF 100uF 5 5 dig 100nF Continuity and Diode Test Continuity 10000 range selected audible tone sounds for impedance 100 Diode Test Test current approximately 0 5mA displays voltages up to 1 2V Maximum Open Circuit 4V Voltage Maximum Input 300V DC or AC rms any range DISPLAY Display Type High contrast LCD Main display 4 digits 17mm high secondary display 5 digits 10mm high Scale Length 474 digits 12000 counts in most modes Annunciators LCD annunciators for all ranges functions and program modes Reading Rate Varies with function maximum 4 sec Overrange Display flashes 12000 if input too great for range Overflow Displays Or if calculated result overflows display COMPUTING FUNCTIONS Null Relative Stores current reading and subtracts it from future readings Q Null Hold Additional non volatile function for nulling test lead resistance Reading is frozen T Hold Touch amp Hold Reading is frozen when stable dB Displays measurement in dBm relative to 600 or other user entered impedance AC plus DC Deviation Ax B Limits Min Max Power VA Data Logger INTERFACES The RMS value of the ac plus dc parts of the signal is calculated and displayed Displays 96 deviation from entered reference value Linear
20. Baud rate exit Baud rate selection by pressing Baud again or Esc The other parameters are fixed and are as follows Start bits 1 Data bits 8 Parity None Stop bits 1 With the interface set up a reading will be sent to the device each time the Print key is pressed Printing Data Logger Readings Set the interface up as described in the appropriate section above Press Shift Logger Rcl the shifted function of EDIT to recall the logger results to the display Pressing Print whilst in this logger display mode will cause the complete contents of the logger to be printed Each result is printed on a separate line and consists of the store location value and measurement units 26 Calibration General Calibration is guaranteed as in the specification The Manufacturers provide a re calibration service as do most of their agents overseas Where owners wish to carry out re calibration themselves this should only be done by skilled personnel with access to precision equipment working in conjunction with the service manual which may be purchased directly from the Manufacturers or their agents overseas Zero Calibration An automatic zero calibration of the basic DC measurement circuitry is performed every time that the instrument is switched on If the meter has been stored at a temperature outside the specified operating range and is switched on before it has fully acclimatised to the working environment meter accuracy may be affected as t
21. THURLBY THANDAR INSTRUMENTS Model 1705 PROGRAMMABLE TRUE RMS MULTIMETER INSTRUCTION MANUAL Introduction Specifications Safety EMC Installation General Operation Making Basic Measurements Dual Measurement Mode Advanced Features Data Logging and Printing Calibration Maintenance Remote Operation Remote Commands General Commands Main Display Commands Dual Measurement Mode Commands First Level Modifier Commands Second Level Modifier Commands Data Logging Commands Calibration Commands Default Settings Table of Contents co Co N 12 16 19 21 25 27 28 29 34 34 35 of 37 38 40 40 41 Introduction This programmable true RMS multimeter has dual measurement capability and a dual display T which can show either two independent measurements a measurement together with its range or a measurement with one of the many calculated functions available The key features are e Large high contrast liquid crystal dual display e 0 04 basic accuracy 12000 counts e Manual or autoranging e DC and AC Volts DC and AC current Resistance Capacitance and Frequency measurement Continuity and Diode checks e True RMS AC and AC DC measurement e Display nulling and Ohms null e Touch hold mode holds onto a stable reading until updated e 100 point data logger e Measurement post processing to give dB and power measurement with settable reference impedance percentage deviation from a user entered re
22. all the other annunciators off For example selecting Edit mode for the Limits modifier will show The position of the decimal point and the units of the parameter being edited are determined by the range in use at the time the modifier is selected The exception is A of Ax b which has its decimal point position fixed after the first digit i e the range for A is 0 0001 to 9 9999 If the meter is in autorange mode and the range in use is inappropriate e g Ohms function is selected with no input present causing it to autorange to 20MQ first select the required range with the Range Up Range Down keys Once edit mode is selected editing is controlled by the Range Up Range Down and Auto Man keys which have the edit mode functions of Change Digit Step Digit and change sign respectively as indicated by the blue legend beside the keys The flashing digit is the one currently editable its value can be incremented through the values 0 to 9 and back to 0 using the Change Digit key The selection of the editable digit is made with the Step Digit key which moves the flashing digit from left to right with wrap around from the rightmost digit to the leftmost The sign of the number can be changed with the digit cursor in any position by alternate presses of the key During number editing the default value can always be entered by pressing Clr the edit function of Cancel The current meter reading can be entered as the new number by
23. at measurement are displayed e g ac Volts and the dB equivalent in this case only a single measurement is being made and the measurement rate is unchanged further information is given later in this section Dual Measurement Combinations All practical combinations of functions are allowed in Dual Measurement Mode those of no practical use e g dc Volts and Frequency are not selectable The full list is as follows Main Display Secondary Display Vdc Vac Idc lac Vac Vdc Idc lac Hz Idc Vdc Vac lac lac Vdc Vac Idc Hz Hz Vac lac Capacitance Q and Continuity Diode check cannot meaningfully be combined with other measurements and are therefore always excluded from the secondary display Vac Vdc and lac ldc are also excluded because they already involve dual measurements when they are being used no secondary display can be set The same measurement can be displayed in both displays if required at the single measurement update rate in this mode the displays both use the range set for the main display The secondary display is selected by pressing Select 2nd followed by the function pressing an illegal function will cause a warning beep and the key entry will be ignored Pressing Select 2nd twice will return the meter to single measurement mode with the range shown in the secondary display pressing Select 2nd followed by Cancel turns the secondary display off Selecting any main display function will also return the meter to s
24. ater use e g by another application which could for example generate a graph of the data The following sections detail the operation of the instrument via both GPIB and ARC RS232 Where operation is common no distinction is made between the two where differences occur these are details in separate sections for GPIB and ARC RS232 GPIB Selection The required interface must be selected using the rear panel slide switch before the meter is switched on Set the switch and switch on if GPIB is selected the main display will show IEEE for 1 second as verification Address and Baud Rate Selection Each instrument connected to the ARC or GPIB bus must be assigned a unique address and in the case of ARC all must be set to the same baud rate To set the address press Shift then Addr the shifted function of FUNCTION the main display shows Add and the secondary display shows the current address setting Increment decrement the address with the Range Up Range Down beep or enter the default address 1 by pressing Clr the edit function of Cancel Exit address selection mode by pressing Esc To set the Baud rate press Shift then Baud the shifted function of Run the main display shows bAUd and the secondary display shows the current Baud setting Step through all possible settings using the Range Up Range Down keys or enter the default rate 9600 by pressing Clr the edit function of Cancel Exit Baud selection mode by pressing Esc Two
25. cessed from a menu using the FUNCTION modifier key All modifiers are post processors of some sort which act on the basic measurement to produce a modified result Most modifiers make use of the secondary display to show either the modified results with the actual reading in the main display or vice versa consequently Dual Measurement Mode is not allowed when running any of the modifiers Selecting any modifier cancels Dual Measurement Mode First Level Modifiers Hold The following modifiers are selected directly using a dedicated key Pressing Hold freezes the main display and shows the HOLD annunciator The normal updated reading will be shown in the secondary display if the meter is not in dual measurement mode except for capacitance Hold does not operate on the secondary display Hold can be used with dB and Null Hold is cancelled by pressing Hold again or by changing range or function T Hold Null dB T Hold is selected by pressing Shift then T Hold the shifted function of Hold T HOLD shows in the display In this mode the meter will hold a reading until a new non zero measurement has been detected this allows the user to touch probe the measurement point remove the probes and read the meter afterwards Note however that care should be taken when using T Hold with the most sensitive voltage ranges when the probes are lifted from the circuit being measured their high impedance means that stray pick up might generat
26. d 10 C without degradation of its safety It has been designed for Installation Category Il measurement use to 600VDC ACrms and Installation Category measurement use to 1000VDC 750VACrms The full definitions of Categories and II can be found in IEC664 but the following can be taken as a guide Installation Category is signal level e g telecommunication electronic equipment with smaller transient over voltages than Installation Category ll Installation Category Il is local domestic supply level e g portable equipment and appliances In particular Category II does not include distribution level supplies e g three phase installations which are classified as Installation Category Ill For this equipment 2500V is the maximum peak transient overvoltage that can be tolerated by any terminal with respect to earth ground without impairing safety Use of this instrument in a manner not specified by these instructions may impair the safety protection provided Do not operate the instrument outside its rated supply voltages or environmental range In particular excessive moisture may impair safety When the instrument is connected to its supply or its inputs are connected to live voltages terminals may be live and opening the covers or removal of parts except those to which access can be gained by hand is likely to expose live parts The apparatus shall be disconnected from all voltage sources before it is opened for any adjustment rep
27. e The Delta 96 maximum display is 999 99 and the resolution is fixed at 0 01 The display shows Or if the maximum is exceeded To select Delta press the FUNCTION key until the Delta symbol flashes in the menu of modifiers Pressing Edit will then permit the reference to be set as described earlier in the Number Editing section during edit the main display shows rEF The reference value is a number variable over the range 00000 to 99999 the decimal point position is set by the range in use during edit The reference default value of 10000 decimal point determined by range can be entered by pressing Clr and the latest meter reading can be entered by pressing Copy rdg Limits High and low limits can be set against which the current reading is compared When running the main display shows the actual reading and the secondary display shows PASS reading between or equal to set points HI reading gt HI or LO reading lt LO Having selected Limits from the modifier menu with the FUNCTION key LIMITS symbol flashing pressing Edit will permit the HI and LO limits to be set in turn using the Change Digit Step Digit and keys as previously described in the Number Editing section HI or LO will show in the main display during edit as appropriate The units and decimal point position are set by the current meter range which must be selected before the modifier is selected and editing begins If the value and resolution of the
28. e another valid reading and the true T Hold reading may be lost T Hold operates in both manual and autorange modes it is cancelled by pressing Hold again or by changing function Null is selected by pressing the Null key Pressing Null locks the meter in the selected range shows NULL and MAN in the display stores the current reading and subtracts it from all following readings The normal un nulled reading will be shown in the secondary display if the meter is not in dual measurement mode except for capacitance Null can be used with Hold Null is cancelled by pressing Null again or by changing range or function dB deciBel can be selected only when Vac is already in the main display Pressing dB shows the dB value of the Vac measurement referred to the current impedance setting and displays the dB annunciator dBs are shown in a fixed format with 0 1dB resolution whatever range the Vac measurement is being made on If no secondary function is selected the normal reading will be shown in the secondary display The value displayed is in dBm and is calculated from the formula dB 10 logio 1000 x V7 R Where R is the selected reference impedance 21 The default reference impedance is 600Q but a different value can be selected by entering the edit mode With dB already selected press EDIT the main display will now show rEF and the current impedances will be shown in the secondary display Use the Range Up Range Down keys t
29. e because the two readings are made alternately However the reading rate is not simply halved because enough time must be allowed for each measurement to fully settle to the different conditions before the display is updated unless this is done neither display will reliably show the true measurement value The settling time depends on the differences between the main and secondary measurement range function and signal level the delay is longest when both displays show an ac measurement Note that the settling times allowed assume a steady state signal varying signals will give unpredictable readings The table below summarises the measurement time i e the time for the measurement to settle and the display to be updated for each parameter in all the permitted display combinations Main Secondary Measurement Time Any Function None 25s Vdc Vac Idc lac Hz Same as Main 25s Vac lac Hz 25s Hz Vac lac 25s Vac lac Vdc Idc Hz OS Vdc Idc Hz Vac lac OS Vac lac As T lac Vac 4s T T This time is extended to 8s if the measurement value is 1000 counts to allow for the increased settling time required by the True RMS converter at low input levels 20 Advanced Features The advanced features of this multimeter are all accessed using the keys in the top two rows of the keyboard Broadly they divide into First Level Modifiers which are accessed via dedicated keys dB Hold and Null and Second Level Modifiers which are all ac
30. e length is 12000 for all measurements except capacitance full scale 1200 and the 20MQ resistance range full scale 2400 Function Selection All functions are directly selected by pressing the appropriate function key Vdc Hz etc Changing function always cancels any modifiers already running and sets autorange providing the appropriate function has been selected e g Q for resistance measurement and the parameter to be measured is within the range of the meter a valid reading should always be shown The exception is 10A current measurement which requires manual range selection see next section The units and function are shown in the display e g mV dc together with AUTO to indicate autorange When a function is selected in this way the smaller secondary display will show the operating range with units except for capacitance If this is not required the secondary display can be turned off by pressing Select 2nd followed by Cancel the range will be displayed again when the function is next changed or by pressing Select 2nd twice The Continuity Diode check test key selects continuity test with the first press and then alternates between the modes with further presses The appropriate annunciator indicates the current selection Continuity sets the meter to the 1000 00 range and buzzes for values below approximately 100 Vdc Vac or Idc lac measurements are made by pressing both Voltage range or both current range keys toge
31. e mA socket are protected by a 500mA F HBC fuse and the 10A range using the 10A socket is protected by a 10A F HBC fuse Both fuses are fitted inside the instrument and replacement is described in the Maintenance section later in the manual Note After measuring high current using the 10A input thermal voltages are generated that may create errors when making measurements on the most sensitive dc voltage current or Ohms ranges immediately afterwards To ensure that the specified accuracy is maintained allow 10 minutes for the thermal effects to fade before making sensitive measurements Making Resistance Measurements Resistance measurements are made using the V O and COM sockets Residual test lead resistance can be nulled out using the Ohms null facility as follows Connect the test leads together and press Shift Null O Null is the shifted function of Null The 1000 range is set automatically and the NULL annunciator flashes the meter stores the reading that it detects after 5 seconds provided that it is less than 1 009 100 counts A beep sounds when the null is completed and the display should show zero Ohms and no NULL annunciator the meter returns to its previous range or AUTO if autorange had been operational before Ohms null was selected If the reading cannot be nulled because the offset is too large the reading will not change and the buzzer will not sound The Ohms null is stored as a floating point value which is u
32. ed reading exceeds 99999 Or is shown in the secondary display to indicate over range To select Ax b press the FUNCTION key until the Ax b symbol flashes in the menu of modifiers pressing Edit will then permit the two parameters A and b to be set as described earlier in the Number Editing section A or b will show in the main display during edit as appropriate A is variable from 0 0001 to 9 9999 with the decimal point in a fixed positon after the first digit the default value is 1 0000 entered by pressing Clr b is a floating point number variable over the range 00000 to 99999 with the decimal point and units set by the range selected during editing the default value is zero entered by pressing Clr and the current measurement value can be entered as b by pressing Copy rdg 23 Watts VA 24 The Watts function calculates power using the formula Watts V R It can only be run when Vdc or Vac are selected in the main display The reference impedance can be set anywhere between 1 and 99999 Ohms To select Watts press the FUNCTION key until the W symbol flashes in the menu of modifiers Pressing Edit will then permit the reference impedance to be set as described earlier in the Number Editing section rEF shows in the main display while the reference impedance in the secondary display is being edited The VA function calculates power by multiplying voltage and current readings The meter must be connected for both vol
33. ener instrument or controller to suspend the output of a talker The listener must send 11H XON before the talker will resume sending This is the only form of handshake control supported by ARC ARC Interface Control Code List 02H SAM SetAddressable mode 03H UNA Universal Unaddress control code 04H LNA Lock Non Addressable mode control code 06H ACK Acknowledge that listen address received OAH UCT Universal Command and response Terminator ODH CR Formatting code otherwise ignored 11H XON Restart transmission 12H LAD Listen Address must be followed by an address belonging to the required instrument 13H XOFF Stop transmission 14H TAD Talk Address must be followed by an address belonging to the required instrument 18H UDC Universal Device Clear GPIB Interface The GPIB interface pin connections are as specified in IEEE Std 488 1 1987 The instrument contains the following IEEE 488 1 subsets Source Handshake SH1 Parallel Poll PPO Acceptor Handshake AH1 Device Clear DC1 Talker T8 Device Trigger DTO Listener L4 Controller CO Service Request SRO Electrical Interface E2 Remote Local RL2 This instrument does not support parallel polling or IEEE 488 2 error handling 32 ARC Remote Command Formats Commands are sent as PROGRAM MESSAGES by the controller A PROGRAM MESSAGE gt consists of zero or more PROGRAM MESSAGE UNITS each separated by a PROGRAM MESSAGE UNIT SEPARATOR which is the semi colon character
34. equency of an ac current the minimum measurable signal is typically 1096 of range maximum e g 0 1mA on the 1mA range Zero Calibration 18 An automatic zero calibration of the basic DC measurement circuitry is performed every time that the instrument is switched on However if the meter has been stored at a temperature outside the specified operating range and is switched on before it has fully acclimatised to the working environment accuracy may be affected as the meter s temperature changes To ensure optimum accuracy particularly on the 100mV and mA current ranges zero calibration can be repeated when the meter has acclimatised by using the Null key as follows Press the Null key and continue to hold it down until nULL shows in the main display about 3 seconds later nULL continues to show whilst the auto zero is being performed typically 5 seconds on completion the display returns to it previous mode Auto zeroing in this way cancels Null if this was already selected press Null again to re select if required Dual Measurement Mode In Dual Measurement Mode a completely independent but complementary measurement can be made and displayed on the secondary display The two independent measurements are actually made alternately not simultaneously and the display update rate for each measurement is consequently reduced Note that this is not the same as when in dual display mode both a measurement and a modified version of th
35. f EN61010 1 Safety Requirements for Electrical Equipment for Measurement Control and Laboratory Use It is an Installation Category II instrument intended for operation from a normal single phase supply WARNING THIS INSTRUMENT MUST BE EARTHED WHEN OPERATED FROM A MAINS SUPPLY Any interruption of the mains earth conductor inside or outside the instrument will make the instrument dangerous Intentional interruption is prohibited The protective action must not be negated by the use of an extension cord without a protective conductor When operated from the internal batteries the multimeter meets the safety requirements for a Safety Class II reinforced insulation product and does not require grounding for safety The test leads supplied with this instrument meet the requirements of IEC1010 2 031 and are rated to 1000V Cat III use only these test leads with the meter or a set of equivalent performance This instrument has been tested in accordance with EN61010 1 and has been supplied in a safe condition This instruction manual contains some information and warnings which have to be followed by the user to ensure safe operation and to retain the instrument in a safe condition This instrument has been designed for indoor use in a Pollution Degree 1 environment no pollution or only dry non conductive pollution in the temperature range 5 C to 40 C 20 80 RH non condensing It may occasionally be subjected to temperatures between 5 an
36. ference linear scaling with offset limits comparison for go no go testing automatic storage of minimum and maximum readings e Remote control via addressable RS232 standard or GPIB factory fit option interfaces e Closed case software calibration e Fully compliant with EN61010 1 Safety and EN61326 EMC standards T Licensed under U S Pat 4 825 392 Specifications ACCURACY Accuracies apply for 1 year 19 C to 25 C Temperature coefficient outside these limits is 0 1 x quoted range accuracy per C DC Volts Range Accuracy Resolution 100mV 0 06 3 dig 1000mV 0 04 2 dig 100uV o 10V 0 06 2dig 1mV 100v 0 06 2dig Om 1000V 0 06 2 dig 100mV Input Impedance 10MQ lt 100pF except for Vdc plus Vac measurement when the 1MQ ac attenuator is in parallel with the 10MQ dc attenuator Maximum Input 1kV DC or AC peak any range NMR gt 60dB at 50 60Hz 1kQ Unbalanced CMR gt 90dB at DC 50Hz 60Hz Maximum Allowable AC Voltage While Measuring DC Voltage Range MaxAC Range MaxAC Thetable shows the maximum AC voltage 100mV 1000mV 80V 45Hz 50kHz that can be applied without 100V 200V 1000V 1000V affecting the accuracy of the DC measurement AC Volts True RMS hcec aee wma mw 0 2 20 dig 0 2 20 dig 1 80 dig Accuracy specifications apply for readings between 1 000 and 12 000 counts Additional error at crest factor 3 typically 0 2 Extended frequenc
37. for the standard READ response see that command section for details If the Watts function is not running a zero value will be returned VA Sets the VA function Vac or Vdc must first have been selected in the main display and the meter must be connected for both voltage and current measurement VA shows in the secondary display VA Returns the result of the VA calculation The syntax of the response is ASCII data rmt where ASCII data is an 18 character string divided into two fields value followed by units exactly as for the standard READ response see that command section for details If the VA function is not running a zero value will be returned CANCEL Cancels the second level modifier currently running 39 Data Logging Commands LOGON lt nrf gt Sets Data Logger running and optionally sets the internal logger interval timer when no interval is specified the existing value is used Setting the interval to 0000 disables the timer but still allows the logger to be triggered manually from the keyboard or by remote command TRIG see below triggering by remote contact closure is not possible during remote control operation LOG Returns the contents of all valid locations in the data logger store starting at location 001 The syntax of the response is ASCII data gt lt rmt gt where ASCII data consists of up to 100 complete results separated by commas each result comprising three fields The
38. he meter s temperature changes To ensure optimum accuracy the zero calibration can be repeated when the meter has acclimatised by using the Null key as follows Press the Null key and continue to hold it down until nULL shows in the main display about 3 seconds later nULL continues to show whilst the auto zero is being performed typically 5 seconds on completion the display returns to its previous mode DC zero calibration affects all measurement ranges but ac measurements resistance and capacitance have additional zero adjustments which are only made during the full calibration routine However if there is a small residual offset on the most sensitive ranges it can always be nulled out using the Null or Ohms Null facilities see appropriate sections 50Hz 60Hz Rejection The analogue to digital converter operation can by software adjustment be optimised for either 50Hz or 60Hz ac line rejection the NMR and CMR figures given in the Specification assume that the appropriate frequency rejection has been set as described below To check or change the ac line rejection setting press Shift followed by Address the shifted function of FUNCTION and then depress the Cal switch accessible through the front panel Cal hole with a small tool until it clicks on The main display will show REJ and the secondary display will show either 50 or 60 Press the Range Up Range Down keys to toggle between 50 and 60Hz rejection When the correct freque
39. he rechargeable position there is a risk of explosion if the meter is connected to an AC supply The Rechargeable batteries are charged at a trickle rate of C 20 the time to fully charge from completely discharged is approximately 28 hours Low battery condition is indicated by showing the battery symbol in the top left hand corner of the display when this symbol shows approximately 5 of battery life remains 11 General Operation This section is a general introduction to the features and organisation of the multimeter intended to be read before using the instrument for the first time Detailed operation is covered in later sections starting with Making Basic Measurements Connections Input Sockets The input sockets are 4mm safety sockets on a 19mm pitch designed to accept 4mm safety plugs with fixed or retractable shrouds The sockets are all rated to 1000V Cat 1 600V Cat II with respect to earth ground The input impedance between V Q and COM is nominally 10MQ on dc ranges and 1MO on ac ranges The black COM socket is considered less positive than the red socket The mA 10A current sockets are low impedance the voltage burden between mA 10A and COM at full scale is lt 250mV for the mA ranges and 500mv for the 10A range The black COM socket is considered less positive than the white mA 10A sockets Multimeter Test Leads A The test leads supplied meet the requirements of IEC1010 2 031 and are rated
40. ingle measurement mode The secondary measurement with the exception of the 10A current ranges always autoranges The 10A current ranges are set by first selecting the function Select 2nd followed by lac or Idc then pressing Select 2nd followed by Range Up return to the mA autoranges is by pressing Select 2nd followed by Range Down However if both main and secondary displays are making current measurements the range of the secondary measurement is always that of the main display If Vdc and Vac are the two measurement functions autoranging of the secondary display is restricted such that the dc measurement range is not lower than the ac range this ensures that the dc measurement is not affected by a high ac signal see the table in the Specification page 3 For example if the main display is set to 10Vdc the secondary display can autorange between the 100mV 1000mV and 10Vac ranges In this example low levels of ripple could be measured on the 100mV range on a 10Vdc supply rail but an ac input gt 12V will cause the secondary display to flash 12000 overload warning the user to select a higher main display dc range such that the secondary ac measurement is in range Similarly if the main display is set to 100Vac then the secondary display will not autorange below 100Vdc even for small dc inputs When frequency is selected for the secondary display the measurement is made using the ac range set in the main display This presents no pr
41. lacement maintenance or repair Any adjustment maintenance and repair of the opened instrument under voltage shall be avoided as far as possible and if inevitable shall be carried out only by a skilled person who is aware of the hazard involved If the instrument is clearly defective has been subject to mechanical damage excessive moisture or chemical corrosion the safety protection may be impaired and the apparatus should be withdrawn from use and returned for checking and repair Make sure that only fuses with the required rated current and of the specified type are used for replacement The use of makeshift fuses and the short circuiting of fuse holders is prohibited Do not wet the instrument when cleaning it and in particular use only a soft dry cloth to clean the display window The following symbols are used on the instrument and in this manual h WARNING risk of electric shock sis aee CAUTION refer to accompanying documentation direct current incorrect operation may damage the meter Nuy alternating current EMC This instrument has been designed to meet the requirements of the EMC Directive 89 336 EEC Compliance was demonstrated by meeting the test limits of the following standards Emissions EN61326 1998 EMC product standard for Electrical Equipment for Measurement Control and Laboratory Use Test limits used were a Radiated Class B b Conducted Class B c Harmonics EN61000 3 2 2000 Class A the i
42. mmands in the REMOTE COMMANDS section Responses from the instrument to the controller are sent as RESPONSE MESSAGES A RESPONSE MESSAGE consists of one RESPONSE MESSAGE UNIT followed by a RESPONSE MESSAGE TERMINATOR A RESPONSE MESSAGE TERMINATOR is the new line character with the END message NL END Each query produces a specific RESPONSE MESSAGE which is listed along with the command in the REMOTE COMMANDS section WHITE SPACE is ignored except in command identifiers e g C LS is not equivalent to CLS WHITE SPACE is defined as character codes 00H to 20H inclusive with the exception of the NL character OAH The high bit of all characters is ignored The commands are case insensitive 33 Remote Commands This section details all the commands available Note that each command is completely executed before the next command is started When a command generates a response that response will be sent immediately if in non addressable mode or when addressed to talk if in addressable mode Sending any valid command clears XOFF The following nomenclature is used lt string gt Any valid string listed for the command the lt gt are not required Any item s enclosed in these brackets are optional parameters lt rmt gt RESPONSE MESSAGE TERMINATOR i e Carriage Return character followed by New Line character ODH OAH lt nrf gt A number in any format e g 12 12 00 1 2 e1 and
43. ncy has been selected to suit the local ac supply release the Cal switch by depressing it again with a small tool and then press Run the display should return to normal measurement mode 27 Maintenance Routine maintenance is limited to re calibration described above battery replacement described in the Installation section and cleaning The only repair maintenance that can be carried out by the user is current range fuse replacement Cleaning If the meter requires cleaning use a cloth that is only lightly dampened with water or a mild detergent Polish the display window with a soft dry cloth WARNING TO AVOID ELECTRIC SHOCK OR DAMAGE TO THE METER NEVER ALLOW WATER TO GET INSIDE THE CASE TO AVOID DAMAGE TO THE CASE OR DISPLAY WINDOW NEVER CLEAN WITH SOLVENTS Current Range Fuses The mA socket is protected by a 500mA F HBC fuse and the 10A socket by a 10A F HBC fuse both mounted internally To replace a fuse proceed as follows 1 Disconnect the instrument from all voltage sources 2 Unclip the front bezel by gently pulling the centre of each long edge up and forward The case halves are held together by 4 plastic push rivets Use the blade of a small screwdriver in the slot beside each rivet to first ease out the rivet head and then fully remove the rivet body Separate the case halves Visit www tti test com for further details Replace the fuse with one of an identical rating using the diagram below as a guide
44. nd returns the meter to single measurement mode To edit the parameters of a secondary modifier press Edit when the required modifier is either selected i e flashing in the menu or is already running the annunciator flashes with all other modifier symbols off During editing the name of the modifier parameter is shown in the main display e g A for Ax b HI for High Limit etc and the parameter value is shown in the secondary display The digits of this number are incremented and selected using the Change Digit Step Digit and keys as described earlier in the Number Editing section Pressing Clr the edit function of Cancel enters the default value of the parameter pressing Copy rdg the edit function of Null enters the current meter reading as the parameter value when this is permitted When editing is complete pressing Edit again will save the parameter and display the next one to be edited if there is more than one Pressing Run exits edit mode saving the parameters and runs the modifier Pressing Esc exits edit mode without saving any new parameters the previous ones are restored and exits the modifier Pressing FUNCTION exits edit mode saving the parameters and returns to the modifier menu Delta 22 The Delta function displays in the secondary display the percentage deviation of the current measurement from a reference value the main display shows the normal reading Delta Reading Reference 96 Referenc
45. nstrument is Class A by product category Immunity EN61326 1998 EMC product standard for Electrical Equipment for Measurement Control and Laboratory Use Test methods limits and performance achieved were a EN61000 4 2 1995 Electrostatic Discharge 4kV air 4kV contact Performance B b EN61000 4 3 1997 Electromagnetic Field 3V m 80 AM at 1kHz Performance B c EN61000 4 11 1994 Voltage Interrupt 1 cycle 100 Performance A d EN61000 4 4 1995 Fast Transient 1kV peak AC line 0 5kV peak DC Outputs Performance B e EN61000 4 5 1995 Surge 0 5kV line to line 1kV line to ground Performance A f EN61000 4 6 1996 Conducted RF 3V 80 AM at 1kHz AC line only DC Output connections lt 3m not tested Performance A According to EN61326 the definitions of performance criteria are Performance criterion A During test normal performance within the specification limits Performance criterion B During test temporary degradation or loss of function or performance which is self recovering Performance criterion C During test temporary degradation or loss of function or performance which requires operator intervention or system reset occurs Where Performance B is stated the multimeter will continue to function but accuracy may deviate from Specification under the test conditions However the possible deviations are small and infrequent and are unlikely to be a problem in practice
46. o scroll through the list of impedances which can be set 50 75 93 110 124 125 135 150 250 300 500 600 900 1000 1200 and 800022 Pressing Clr the edit function of Cancel enters the default value of 6000 To exit edit mode saving the new reference impedance press Run or dB to exit edit mode without changing the value i e the previous value is restored press Esc Hold can be used with dB mode but selecting any other function will cancel dB pressing dB again will also cancel it Second Level Modifiers Second level modifiers are mutually exclusive selecting a second level modifier cancels any previous one Selecting a second level modifier cancels Dual Measurement Mode Pressing Cancel or changing the function or range will cancel the modifier but the parameter values are saved Selection and Editing All modifiers are selected by pressing the FUNCTION key The first press shows all the available modifiers as a menu with the last selected one flashing Subsequent presses of FUNCTION make each modifier flash in turn the current selection is the flashing one To run the selected modifier press Run at this point the flashing modifier symbol is now static and all the other modifiers annunciators are off When running the modified value appears on the secondary display the main display continues to show the un modified value Pressing Cancel during modifier selection or while a modifier is running cancels the modifier a
47. oblems if the main display is in autorange but if a higher range has been set manually such that the reading is less than 1096 of the range maximum the signal level may not be adequate for frequency measurement 19 Making Voltage and Current Dual Measurements Measuring ac and dc Volts or ac Volts and frequency etc still only require two measurement probes because both parameters of the dual measurement are made at the same physical point Simultaneous measurement of voltage and current on the same circuit will however require a third connection see the diagram All inputs 1kV Cat I 600V Cat TT max to L V uF FUNCTION Run gt 1000V DC AN 750V AC Addr Baud 2 LOAD EDIT Cance ol Gr C M T Rcl Logger Clr i Range amp EL Change Digit A A Auto Man Range FUSED Step Digit gt 10A Manual Only E l Note that the voltage measured at the multimeter terminals is that across the load plus the voltage drop in the common lead which is now carrying the whole circuit current Even if the resistance of the lead is very low errors may arise at high currents and low voltages i e low load resistance because the lead resistance becomes significant compared with the load Measurement Update Times As discussed at the beginning of this section the reading update rate is reduced in Dual Measurement Mod
48. pressing Copy Rdg the edit function of the Null key this is not allowed for A of Ax b If the modifier has more than one parameter pressing Edit will save the number just edited and display the new parameter Number editing can always be exited without changing the parameter being edited i e the previous value is restored by pressing Esc the edit function of Local To exit edit mode with the new number stored press Run to operate the modifier or Edit if there is another parameter to be edited To exit edit mode with the new number stored but the modifier not running press FUNCTION to return to the modifier list and then Cancel If the range is subsequently changed the number is retained and will be correctly displayed if edit mode is reselected in the new range Note however that if a lower range is selected and the number is too large to be shown on that range the display will read 99999 The Change Digit key is also used to increment through the available choices during the editing of those parameters which have a limited selection of numbers these include the reference impedance for dB measurement interface address and Baud rate The Range Up and Range Down keys autorepeat if held autorepeat also operates when these keys are used in edit mode 15 Making Basic Measurements This section describes how basic measurements are made i e single measurement mode only and no post processing of the results Scale Length The scal
49. ries provide back up in the event of an AC power failure useful if the meter is baby sitting making for example Min Max measurements over a long time period When the instrument is switched on with the Operate key the display first shows all the display segments whilst running an auto zero routine before setting the operating conditions as described below Power up Settings At power up the default action is to restore power down settings including any modifiers selected at the time that the meter was turned off To restore factory default settings see Default Settings section hold the Cancel key depressed whilst the meter is turned on with the Operate key the buzzer will sound to signify that the defaults have been restored To review the revision of the installed software hold the Shift key depressed whilst the meter is turned on with the Operate key the revision will be shown as r x x until the Shift key is released To show all the display segments together i e perform a display test hold any other key depressed whilst the meter is turned on with the Operate key the display will continue to show all segments until another key is pressed Buzzer A short beep is sounded whenever a valid key is pressed Longer beeps are reserved to indicate illegal key presses e g selecting Hz in the secondary display when the primary display has been set to Vdc such keystrokes are not accepted 13 Keyboard
50. same value If Min Max mode is already running Min and Max are reset to the same value and recording starts again 38 MM Returns the recorded Min and Max values The syntax of the response is ASCII data for Min gt lt ASCII data for Max gt lt rmt gt where each ASCII data is an 18 character string divided into two fields value followed by units exactly as for the standard READ response see that command section for details The two 18 character strings are separated by 2 spaces AXB lt nrf gt lt nrf gt AXB Starts the Ax b scaling function and optionally sets the A and b parameters if A and b are not sent the existing values are used Returns the result of the Ax b scaling function The syntax of the response is ASCII data rmt where ASCII data is a 10 character string in the same format as the first value field of the standard READ response see that command for details If Ax b is not running a zero value will be returned WATTS lt nrf gt Selects the Watts function and optionally sets the reference impedance if no impedance is specified the existing value is used Vac or Vdc must first have been specified in the main display Watts shows in the secondary display WATTS Returns the result of the Watts calculation The syntax of the response is ASCII data gt lt rmt gt where ASCII data is an 18 character string divided into two fields value followed by units exactly as
51. scaling of results with offset Reading displayed with HI LO or PASS with respect to user defined high and low limits Minimum and maximum reading stored Calculates V R and displays in Watts with respect to a user defined impedance Calculates and displays Volts x Amps Manual or automatic storage of 100 measurements Storage interval 1s to 9999s manually from keyboard or by remote contact closure Full remote control facilities are available through the RS232 all models or GPIB alternative mains only version interfaces RS232 GPIB IEEE 488 Baud rates 2400 9600 or 19200 Complies fully with the ARC Addressable RS232 Chain interface standard Address selectable from the front panel Operational only when the meter is powered from the AC input The meter can be specified with an IEEE 488 interface This is an alternative version which operates only from AC mains IEEE 488 is not a retrofittable option Address selectable from the front panel POWER REQUIREMENTS AC Input 220V 240V or 110 120V AC 10 50 60Hz by internal adjustment 5VA max Installation Category II Batteries 6 x C cells disposable or rechargeable Battery Life 2150 hours from alkaline cells typically 70 hours from rechargeable cells GENERAL Operating Range Storage Range Environmental Safety EMC Size Weight 5 C to 40 C 20 to 80 RH 20 C to 60 C Indoor use at altitudes up to 2000m Pollution Degree 1
52. sed on all ranges it is not lost when the function is changed or when the instrument is turned off Ohms null can be cancelled by either pressing the Q and Cancel keys together by selecting Ohms Null and not generating a sub 1 000 reading within the next 5 seconds or by holding the Cancel key down at power up to restore the system defaults Normal Null can be used together with Ohms Null 17 Making Continuity and Diode Checks Continuity and diode checks are made using the V Q and COM sockets Pressing the Continuity Diode check key selects Continuity mode with the first press the continuity indicator is shown in the display The 1000Q range is selected and readings below approximately 10Q sound the continuity buzzer A further press selects diode check the diode annunciator is shown in the display The 1000mV range is selected and the approximate diode voltage at 0 5mA is shown 1 2V maximum Reverse diode connection will show overload Further presses of the key will alternate between Continuity and Diode check Making Capacitance Measurements Capacitance measurements are made using the V O and COM sockets Capacitance measurement is selected by pressing the uF key Five ranges 10nF to 100uF are available with 1200 count full scale giving resolutions of 10pF to 100nF respectively Zero calibration at the factory is carried out with no test leads connected ideally capacitors to be measured should be connected directly to the
53. set points requires two different ranges to be used to set the values it will be necessary to exit the edit mode and modifier after setting the first limit so that the range can be changed for the second limit The limits can be set anywhere in the range 00000 to 99999 with the decimal point set by the range selected during editing Pressing Clr enters the default value of 00000 pressing Copy rdg enters the current reading Min Max This modifier stores the maximum most positive and minimum most negative values that occur when the modifier is run and displays one or other in the secondary display simultaneously with the current measurement in the main display To select Min Max press the FUNCTION key until the Min Max symbols flash in the menu of modifiers Pressing Run will initiate the function and display the minimum value in the secondary display indicated by the Min symbol only now showing Further presses of Run will alternate the secondary display between Min and Max Min and Max are stored as floating point numbers and the modifier can be operated with the meter changing ranges either manually or by autorange To reset the current min or max without exiting the function select Min or Max with alternate presses of the Run key and press Edit Changing function cancels Min Max Ax b When running the scaled value Ax b is shown in the secondary display and the normal value x is shown in the main display If the scal
54. sockets Test leads if used should be kept as short as possible to minimise stray capacitance but nevertheless a non zero reading will generally be present when the lowest ranges are selected To eliminate this offset it is recommended that the meter reading is nulled once the require range has been selected with the test leads in their measurement positions but no capacitor connected It is also recommended that battery operation is used when making capacitance measurements to minimise reading jitter Note that because the capacitor is discharged between each measurement the reading rate on the 100UF range is slower Making Frequency Measurements Frequency measurements are made using the V O and COM sockets Press the Hz key to select frequency mode Four ranges 100Hz to 100kHz are available giving resolutions of 10mHz to 10Hz respectively over an operating frequency range of 10Hz to 120kHz Reciprocal counting techniques ensure fast reading updates 4 readings second even on the lowest range Measurements are made using the ac Volts input circuitry which is autoranged to provide suitable sensitivity At low signal levels use a screened lead and an adaptor BNC to 4mm plugs 19mm pitch to preserve signal quality and avoid spurious readings from stray pick up The minimum measurable signal is typically lt 30mV rms across the frequency range Frequency can also be measured in dual measurement mode see next section When measuring the fr
55. t lt 1000 gt lt 1200 gt lt 8000 gt DBOFF Cancels DB mode Second Level Modifier Commands DELTA lt nrf gt Selects the Delta function and optionally sets the reference value if no reference is specified the existing value is used The percentage deviation shows in the secondary display DELTA Returns the Delta value The syntax of the response is ASCII data gt lt rmt gt where ASCII data is an 18 character string divided into two fields value followed by 96 exactly as for the standard READ response see that command section for details If Delta is greater than 999 99 the response value will be OVFLOW if the Delta function is not running the response value will be zero LIMITS lt nrf gt lt nrf gt Selects the Limits function and optionally sets the limits LO HI if no reference is specified the existing value is used PASS LO or HI is shown in the secondary display LIMITS Returns the result of the latest Limits comparison The syntax of the response is ASCII data gt lt rmt gt where ASCII data is either PASS LOW HIGH or OFF PASS indicates that the reading was between or equal to one or both of the limits LOW indicates that the reading was less than the LO set limit HIGH indicates that the reading was above the HI set limit OFF indicates that the Limits function was not running MMON Starts the Min Max recording mode initially setting both Min and Max to the
56. tage and current measurement see Making Voltage and Current Dual Measurements section with Vdc or Vac selected for the main display To select VA press the FUNCTION key until the VA symbol flashes in the menu of modifiers Pressing Run will run the modifier the meter automatically switches to dual measurement mode and selects lac or Idc as the secondary measurement for Vac or Vdc main display settings respectively The VA symbol will show in the display and the secondary display will show the power in VA units Data Logging and Printing Data Logger The logger function can store up to 100 readings from the main display in non volatile memory The store is linear without wrap around Readings are triggered by either the internal timer manual key press remote contact closure or RS232 remote command Readings are stored as floating point numbers with their units and reading number but without any form of time stamping Setting and Running the Logger To use the logger first set up the measurement function and range required on the Main display To select Logger press the FUNCTION key until the LOGGER symbol flashes in the menu of modifiers then press Edit to set the logger triggering interval During edit mode the main display shows PEr period and the secondary display shows the logger internal timer period in seconds which can be edited using the Change Digit Step Digit keys as described earlier in the Number Editing section The period can
57. th most other ARC instruments these parameters are fixed ARC Character Set Because of the need for XON XOFF handshake it is possible to send ASCII coded data only binary blocks are not allowed Bit 7 of ASCII codes is ignored i e assumed to be low No distinction is made between upper and lower case characters in command mnemonics and they may be freely mixed The ASCII codes below 20H space are reserved for interface control ARC Interface Control Codes All instruments intended for use on the ARC bus use the following set of interface control codes Codes between 00H and 1FH which are not listed here as having a particular meaning are reserved for future use and will be ignored Mixing interface control codes inside instrument commands is not allowed except as stated below for CR and LF codes and XON and XOFF codes When an instrument is first powered on it will automatically enter the Non Addressable mode In this mode the instrument is not addressable and will not respond to any address commands This allows the instrument to function as a normal RS232 controllable device This mode may be locked by sending the Lock Non Addressable mode control code 04H LNA The controller and instrument can now freely use all 8 bit codes and binary blocks but all interface control codes are ignored To return to addressable mode the instrument must be powered off To enable addressable mode after an instrument has been powered on the Set Addressable
58. ther The reading displayed is the RMS sum dc ac and ac dc is shown beside it Both ac and dc measurements are made on the same range the instrument will autorange to a range which gives an in range reading for both the ac and dc component of the parameter However if the result exceeds the range maximum the meter will autorange up to permit the result to be shown as an in range reading Range Selection 16 Selecting a new function always sets autorange to ensure an in range reading is made with maximum resolution whenever possible the meter ranges up at 12000 counts and ranges down at 1000 counts There are however situations when it is desirable to lock the range for example to stop the meter autoranging to the 20MQ range and back between successive resistance measurements of lower resistance values or to set a lower resolution range when an unstable parameter is being monitored To lock the range change from auto to manual ranging see below Manual range changing is selected either by alternate presses of the Auto Man key which locks the meter in its present range or by using the Range Up Range Down keys which both change the range and lock the meter in that new range The MAN annunciator is displayed to indicate manual ranging Overrange is indicated by flashing the display at 12000 counts Autoranging can be restored by pressing the Auto Man key again As explained later in the appropriate sections secondary functions in d
59. to 1000V Cat III Use only the test leads provided or a set of similar performance to ensure safe operation Alternative test leads should be rated to at least 1000V Cat I 600V Cat II and 10A current capability RS232 12 The RS232 interface only operates when the instrument is run from an ac supply RS232 signal ground is then connected to the safety ground The interface is fully isolated from the measurement system 9 pin D connector compatible with the Thurlby Thandar ARC Addressable RS232 Chain system The pin connections are shows below Pin Name Description 1 Power to optional PC 02 2 TXD Transmitted data from instrument 3 RXD Received data to instrument 4 No internal connection 5 GND Signal ground 6 No internal connection 7 RXD2 Secondary received data 8 TXD2 Secondary transmitted data 9 GND Signal ground Pin 2 3 and 5 may be used as a conventional RS232 interface with XON XOFF handshaking Pins 7 8 and 9 are additionally used when the instrument is connected to the ARC interface Signal grounds are connected to safety ground To ensure compliance with EMC legislation use only screened cable assemblies with screened connectors when connecting to other equipment GPIB IEEE 488 An IEEE 488 interface is available on the alternative mains only version IEEE 488 is not a retrofittable option The GPIB connector is located on the rear panel together with the switch which selects between RS232 and GPIB
60. ual measurement mode are autoranging only the exception is 10A range selection which is manual only for both main and secondary displays at all times Making Voltage Measurements A Voltage measurements are made using the red V Q socket and the black COM socket having selected the appropriate function and range as described above The meter will show a minus sign on dc measurements when the voltage applied to the red socket is more negative than that applied to the black socket The maximum voltage that can be applied between V Q and COM is 1000V DC or 750V AC Cat 1 damage to the instrument may result if this limit is exceeded WARNING The maximum input voltage to ground must not exceed 1000V Cat I or 600V Cat Il dc or ac rms Safety will be impaired if these ratings are exceeded see Safety section at the beginning of the manual Making Current Measurements Having selected the appropriate current function current measurements up to 120mA are made using the white mA socket and the black COM socket current measurements up to 10A are made using the 10A and COM socket The meter will show a minus sign on dc measurements when the polarity of the current is out of the mA or 10A sockets Current measurements using the mA socket can be autoranged between 1 0000 mA and 100 00mA ranges measurements up to 10A can be made using the 10A socket having manually ranged to 10A with the Range Up key The 1mA and 100mA ranges using th
61. umber Editing section The two rows of keys in the upper part of the keyboard give access to all the modifiers i e mathematical functions which act upon the primary measurement function At the simplest level these are for example the display of ac voltages in dBs more complex functions include Ax b scaling delta and data logging The access to and operation of all modifiers is fully explained in the Advanced Features section later in this manual It is sufficient to note here that some keys have different functions during modifier editing indicated by the blue legend beside the keys and some keys have shifted functions following the pressing of the Shift key marked beneath the keys in yellow Number Editing 14 Delta 96 Limits and Ax b modifiers operate with numbers which are set by entering edit mode after the modifier has been selected Number editing operates in the same way for all these modifiers and is described here to avoid repetition in each of the modifier sections The appropriate modifier is first selected by successive presses of the FUNCTION key as described fully in the Second Level Modifiers section Edit mode is entered by pressing the EDIT key whilst the selected modifier is flashing in the modifier menu The primary display changes to show the parameter being edited and the number itself together with the appropriate units is shown in the secondary display the selected modifier symbol continues to flash with
62. w the new voltage setting Mains Lead When a three core mains lead with bare ends is provided it should be connected as follows Brown Mains Live Blue Mains Neutral Green Yellow Mains Earth WARNING THIS INSTRUMENT MUST BE EARTHED WHEN OPERATED FROM AN AC LINE SUPPLY Any interruption of the mains earth conductor inside or outside the instrument will make the instrument dangerous Intentional interruption is prohibited The protective action must not be negated by the use of an extension cord without a protective conductor Battery Operation To fit or replace the six C cells slide off the battery cover at the rear of the instrument and remove the battery tray For safety reasons the battery cover can only be slid off after first removing the security screw with a screwdriver Always refit the security screw after changing the batteries 10 REMOVE SCREW TO SLIDE BACK BATTERY COVER Either rechargeable or disposable cells may be used fit into the battery tray observing the polarity marked in the tray Suitable cells are as follows Rechargeable 2 Amp hour e g NCC200 AN220 VR2C RSH1 8 P 180C Disposable Alkaline e g MN1400 Zinc Carbon e g R14B R148 If batteries are fitted it is essential that the disposable rechargeable selector switch on the rear panel is positioned correctly before applying external power via the AC socket WARNING If disposable batteries are fitted and the selector is set in t
63. wing lt strings gt can be used to set the range lt 100 gt lt 1000 gt lt 10K gt lt 100K gt lt 1000K gt lt 10M gt lt 20M gt CONT Sets the main display to continuity test DIODE Sets the main display to diode test CAP lt string gt Sets the main display to Capacitance and optionally sets the range if no range is specified the display defaults to autorange The following lt strings gt can be used to set the range lt 10NF gt lt 100NF gt lt 1UF gt lt 10UF gt lt 100UF gt FREQ lt string gt Sets the main display to Frequency and optionally sets the range if no range is specified the display defaults to autorange The following lt strings gt can be used to set the range lt 100HZ gt lt 1000HZ gt lt 10KHZ gt lt 100KHZ gt 36 AUTO Sets the main display to autorange except for Continuity or Diode check MAN Sets the main display to manual i e the current range is locked Dual Measurement Mode Commands VDC2 Sets the secondary display to dc Volts autoranging VAC2 Sets the secondary display to ac Volts autoranging IDC2 lt string gt Sets the secondary display to dc Amps and optionally selects mA autoranging or the 10A range if no range is specified the existing setting is used The following strings can be used lt 1MA gt lt 100MA gt 10A If the main display is set to ac Amps the secondary range will be the same as the main display range
64. y performance 100mV range lt 1dB at 50kHz 1000mV 10V and typical 100V ranges 1dB at 100kHz Input Impedance 1MQ lt 100pF Maximum Input 750V rms 1000V peak any range 1kQ Unbalanced CMR gt 60dB at DC 50Hz 60Hz AC DC Voltage Accuracy Total measurement error will not exceed the sum of the separate ac and dc accuracy specifications plus 1 display count Resistance 0 1 3 dig 10mQ 10kQ 0 09 2 dig me emen oe 20MO 0 5 2 dig 10kQ 300V DC or AC rms any range 4V Maximum Input Maximum Open Circuit Voltage DC Current 1mA 0 1 3 dig 100nA 100mA 0 1 3 dig 10uA 10A 1 0 3 dig to 5A 1mA 10A 3 10 dig to 10A 1mA mA ranges 500mA DC or AC rms 250V fuse protected 10A range 10A DC or AC rms 250V fuse protected Maximum Input mA ranges lt 250mV 10A range 500mV AC Current True RMS 1mA 0 3596 20dig 10A 10A 396 20 dig to 10A 1mA Accuracy specifications apply for readings between 1 000 and 12 000 counts Additional error at crest factory 3 typically 0 2 mA ranges 500mA DC or AC rms 250V fuse protected 10A range 10ADC orAC rms 250V fuse protected Typical Voltage Burden Maximum Input mA ranges lt 250mV Typical Voltage Burden 10A range 500mV Frequency 100Hz 0 01Hz 1000Hz 0 01 1 dig 1OktHz Range 100kHz 10Hz to 100kHz Input sensitivity Better than 30m Vrms 100mV range better

accuracy - Farnell

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