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3-56

Basic DMM Operation

Model 2700 Multimeter/Switch System User’s Manual

Example #4 — Scan configuration (Model 7700)

The following commands configure scan channels 101, 102, and 121 of a Model 7700 
installed in slot 1. When channel 101 is scanned, DCV will be selected. When channel 102 
is scanned, 

Ω

2 will be selected. When channel 121 is scanned, DCI will be selected.

NOTE

The following example can be run from the KE2700 Instrument Driver using the 

example named “ConigChan” in 

Table H-1

 of 

Appendix H

.

FUNC 'VOLT',(@101)

' Configure scan channel 101 for DCV.

FUNC 'RES',(@102)

' Configure scan channel 102 for 

Ω

2.

FUNC 'CURR',(@121)

' Configure scan channel 121 for DCI.

NOTE

Detailed information on scanning is provided in 

Section 7

.

Measurement queries

NOTE

For more information on read commands, see Section 8 (Triggering), Section 13 
(SCPI Signal Oriented Measurement Commands), and Appendix D (Signal 

 

Processing Sequence and Data Flow). 

:FETCh?

What it does

This command will simply return the latest available reading from an instrument.

Limitations

If the instrument does not have a reading available (indicated by dashes in the display), 
sending this command will cause a –230, “Data corrupt or stale” error. This query will not 
cause the box to trigger a reading, nor will it “wait” for a result if a reading is in progress. 
It is possible to get the same reading over and over using this query. It will continue to give 
the same result until one of two things has happened:

•

A new reading has been triggered

•

The old reading has been invalidated by changing ranges or by changing function.

Содержание 2700

Страница 1: ...m o c y e l h t i e k w w w E C N E D I F N O C F O E R U S A E M R E T A E R G A User s Manual 2700 900 01 Rev J August 2011 Model 2700 Multimeter Switch System...

Страница 2: ...Model 2700 Multimeter Switch System User s Manual 2011 Keithley Instruments Inc All rights reserved Cleveland Ohio U S A Document Number 2700 900 01 Rev J...

Страница 3: ......

Страница 4: ...form them Otherwise they should be performed only by service personnel Service personnel are trained to work on live circuits perform safe installations and repair products Only properly trained servi...

Страница 5: ...standing on a dry insulated surface capable of withstanding the voltage being measured The instrument and accessories must be used in accordance with its specifications and operating instructions or t...

Страница 6: ...ting and type are the same Other components that are not safety related may be purchased from other suppliers as long as they are equivalent to the original component note that selected parts should b...

Страница 7: ......

Страница 8: ...yclick 1 18 Display 1 18 Status and error messages 1 18 Remote programming display 1 18 Defaults and user setups 1 20 Saving and restoring setups 1 21 Remote programming default and user setups 1 25 R...

Страница 9: ...ent capabilities 3 2 High energy circuit safety precautions 3 3 Performance considerations 3 4 Warm up 3 4 Autozero 3 4 LSYNC line cycle synchronization 3 5 Remote programming autozero and LSYNC 3 6 C...

Страница 10: ...9 Basic measurement programming examples 3 55 Measurement queries 3 56 FETCh 3 56 READ 3 57 MEASure function 3 58 SENSe 1 DATA FRESh 3 58 SENSe 1 DATA LATest 3 59 Examples 3 59 4 Range Digits Rate Ban...

Страница 11: ...l buffer 6 2 Auto clear 6 2 Timestamps 6 4 Storing readings 6 6 Recalling readings 6 6 Buffer statistics 6 8 Remote programming buffer 6 9 Buffer commands 6 9 Programming example 6 15 7 Scanning Scann...

Страница 12: ...d autosettle 8 6 Hold example 8 6 External triggering 8 7 Digital I O 8 7 External trigger 8 8 Voltmeter complete 8 9 External triggering example 8 10 External triggering with BNC connections 8 13 Rem...

Страница 13: ...IFC interface clear 10 8 LLO local lockout 10 9 GTL go to local 10 9 DCL device clear 10 9 SDC selective device clear 10 9 GET group execute trigger 10 9 SPE SPD serial polling 10 9 Front panel GPIB o...

Страница 14: ...d SRQ 11 8 Status byte and service request commands 11 9 Serial poll programming example 11 10 Status register sets 11 12 Register bit descriptions 11 12 Condition registers 11 18 Event registers 11 1...

Страница 15: ...curacy A 9 DC voltage DC current and resistance A 9 AC voltage and AC current A 9 Temperature A 9 Optimizing measurement speed A 10 DC voltage DC current and resistance A 10 AC voltage and AC current...

Страница 16: ...tentials E 2 Thermoelectric generation E 3 Minimizing thermal EMFs E 4 Source resistance noise E 5 Magnetic fields E 6 Radio frequency interference E 6 Ground loops E 6 Shielding E 8 Meter loading E 9...

Страница 17: ...commands G 10 SCPI commands G 10 Command codes G 10 Typical command sequences G 12 IEEE command groups G 13 Interface function codes G 14 H KE2700 Instrument Driver Examples Introduction H 2 Visual B...

Страница 18: ...del 77xx series switching modules QS1 Front and rear panel familiarization Summarizes the controls and connectors of the instrument Rack mounting Covers the options available for rack mounting the Mod...

Страница 19: ...n this manual The symbol on an instrument indicates that the user should refer to the operating instructions located in the manual The symbol on the instrument shows that high voltage may be present o...

Страница 20: ...data logging capabilities This can be modified with the TestPoint application development package optional software KE2700 IVI Instrument Driver Provided for programmers designed for use with applica...

Страница 21: ...or temperature measurements Model 7709 This module is configured as a 6 8 matrix six rows eight columns The matrix consists of 48 crosspoint channels and two backplane isolation channels For system ch...

Страница 22: ...th the Models 7711 and 7712 switching modules Model 7712 SMA N Female SMA to male N type adapter This adapter is used with the Models 7711 and 7712 switching modules S46 SMA X SMA cable male to male S...

Страница 23: ...ng environment uses object oriented technology through a drag and drop interface to build a basic system quickly and without in depth programming Optional toolkits database and statistical process con...

Страница 24: ...nipulation of readings Relative Null offsets or establish baseline values Ratio and channel average Ratio and average calculations for two switching module channels Buffer Store up to 55 000 readings...

Страница 25: ...xer Multiplexer Multiplexer Multiplexer Unique features All DMM functions All DMM functions except amps All DMM functions All DMM functions except amps Model 7705 Model 7706 Model 7707 Model 7708 2 po...

Страница 26: ...8 channels Measure Volts 300V maximum 60V maximum No3 Measure Amps No No No3 Measure Ohms 2 4 wire 2 4 wire No3 Thermocouple Cold Junction No Yes No3 Relay Type1 Latching electro mechanical Solid stat...

Страница 27: ...ils see Switching module installation and connections page 2 3 Front and rear panel familiarization Front panel summary The front panel of Model 2700 is shown in Figure 1 1 Figure 1 1 Model 2700 front...

Страница 28: ...rement function SENSOR Configures temperature measurements Middle Row Unshifted EXTRIG Selects external triggering front panel bus trigger link as the trigger source TRIG Triggers a measurement when i...

Страница 29: ...enabled noise induced by the power line is reduced at the expense of speed GPIB Enables disables GPIB and selects address RS 232 Enables disables RS 232 interface selects baud rate flow control and t...

Страница 30: ...ation being performed TALK Instrument addressed to talk over GPIB bus TIMER Timer controlled triggering in use TRIG External triggering selected trigger link TRIG key or GPIB 5 INPUTS switch Use to se...

Страница 31: ...4 IEEE 488 Connector for IEEE 488 GPIB operation Use a shielded cable such as Models 7007 1 and 7007 2 5 Power module Contains the AC line receptacle power line fuse and line voltage setting The instr...

Страница 32: ...1 16 CAUTION Operating the instrument on an incorrect line voltage may cause damage to the instrument possibly voiding the warranty 2 Before plugging in the power cord make sure that the front panel p...

Страница 33: ...replacing fuse A rear panel fuse located next to the AC receptacle protects the power line input of the instrument If the line voltage setting needs to be changed or the line fuse needs to be replaced...

Страница 34: ...ision Second A01 is the display board ROM revision Installed switching modules are then displayed For example if there is a Model 7700 switching module installed in both slots the following messages w...

Страница 35: ...f operation See Front panel summary page 1 10 for a complete listing of display annunciators NOTE The display test allows you to test display digit segments and annunciators The key test checks the fu...

Страница 36: ...the LOCAL key or sending GTL cancels the message and disables the text message mode DISPlay ENABle ON OFF Control display circuitry This command is used to enable and disable the front panel display...

Страница 37: ...ctory and RST default settings are listed in Table 1 4 Setting differences Set Diff between the two default setups are indicated by checkmarks For remote programming the SYSTem PRESet and RST commands...

Страница 38: ...ress to place the cursor on the present power on setup 5 Use the or key to display the desired setup and press ENTER The instrument returns to the normal measurement state Restoring a setup 1 Press SH...

Страница 39: ...tinuity Beeper On On Digits 4Hdigits 4Hdigits Range 1k 1k Rate Fast 0 01 PLC Fast 0 01 PLC Threshold level 10 10 Current AC and DC Bandwidth AC 30 30 Digits AC 5Hdigits 5Hdigits Digits DC 6Hdigits 6Hd...

Страница 40: ...1 0 Offset 0 0 0 0 Units X X Percent Off Off Reference 1 0 1 0 1 X Reciprocal Off Off Monitor Off Off Output Beeper Never Never Digital Output Off Off Logic Sense High High Pulse No off No off Ratio...

Страница 41: ...t Timer Off Off Reading count No effect No effect Advanced scan Setup No effect No effect Immediate trigger On On Limit triggers Off Off Timer Off Off Reading count No effect No effect Temperature Dig...

Страница 42: ...age AC and DC dB Off Off Reference 1 0 1 0 Digits AC 5Hdigits 5Hdigits Digits DC 6Hdigits 6Hdigits Filter On Off Window 0 1 0 1 Count 10 10 Type Moving Repeat Range Auto Auto Rate DC Slow 5 PLC Slow 5...

Страница 43: ...ntified by the question mark that follows the command word A query command requests queries the programmed status of that command When a query command is sent and Model 2700 is addressed to talk the r...

Страница 44: ...place the instrument in a non continuous measurement mode Most of the other settings for factory and RST defaults are the same For remote programming the following command is used to select function...

Страница 45: ...Press RECALL use edit keys to display readings Press EXIT to exit recall mode CALC1 DATA 1 To avoid problems with remote programming it is good practice to routinely clear the buffer TRAC CLE at the...

Страница 46: ...gn slot 1 as a pseudocard using remote programming The instrument will operate as if a switching module is installed in slot 1 To install a 7700 pseudocard in slot 1 send the following command SYST PC...

Страница 47: ...to is used to make proper connections to the DMM However for system channel operation the user need not be concerned about which switches in the module close Figure 1 5 Connection to DMM for 4 wire f...

Страница 48: ...el keys used to close and open system channels Figure 1 6 Front panel keys to close and open system channels For remote programming the following three commands are used for basic system operation to...

Страница 49: ...ifies the number of readings to store in the buffer For STEP the reading count determines the number of channels to scan Table 1 7 Exercise 2 Close and open channels system channel operation Front pan...

Страница 50: ...an For an advanced scan each channel can have its own unique setup i e function range etc Advanced scanning is covered in Section 7 Figure 1 7 Simple scan operation MIN CHAN XXX INT SIMPLE Display SIM...

Страница 51: ...scan eight channels and store the readings in the buffer Table 1 8 Exercise 3 Simple scanning Front panel operation Command sequence 1 For front panel operation proceed to step 2 For remote programmin...

Страница 52: ...5 Trigger and return multiple readings Exercise 6 Return a single reading continuous triggering Details on the commands to trigger and return readings are provided in other sections of this manual For...

Страница 53: ...ommand sequence to return a single reading while in the continuous trigger state Figure 1 8 Exercise 4 Trigger and return a single reading INIT CONT OFF TRIG COUN 1 SAMP COUN 1 Place 2700 in non conti...

Страница 54: ...adings are automatically stored in the buffer Statistics for buffer readings are also stored in the buffer CALC2 commands are used to calculate and return buffer statistics see Section 6 for details T...

Страница 55: ...esult of the calculation will be returned If there is no MATH function enabled FETCh and CALC DATA will return the basic reading MATH functions are covered in Section 5 2 None of these read commands t...

Страница 56: ...channel number System channel operation Provides detailed information for using system channel operation Multiple channel operation Provides detailed information for using multiple channel operation D...

Страница 57: ...s are rated for 303V The following command queries maximum module voltage SYSTem CARDx VMAX Request maximum allowable voltage for CARDx where x is the slot number for the module For system channel ope...

Страница 58: ...e power If the switching module is already connected to DUT make sure power is removed from all external circuitry Module installation WARNING Slot covers must be installed on unused slots to prevent...

Страница 59: ...nsulation must be rated to the highest voltage that is connected For example if 1000V is connected to the front panel input the test lead insulation for the switching module must also be rated for 100...

Страница 60: ...ocards SYSTem PCARd1 name Install pseudocard in slot 1 SYSTem PCARd2 name Install pseudocard in slot 2 name C7700 C7701 C7702 C7703 C7705 C7706 C7707 C7708 C7709 C7710 C7711 or C7712 Programming examp...

Страница 61: ...mportant points about system channel operation include the following There can only be one system channel This is the channel that is presently displayed and closed on the Model 2700 When a channel is...

Страница 62: ...hen channel 101 is closed using the system channel close keys both the Channel 1 relay and the backplane isolation relay Channel 25 close to connect the channel to the DMM The complete simplified sche...

Страница 63: ...t 1 of the mainframe and a 4 wire function such as 4 is selected When channel 101 is closed using the system channel close keys the Channel 1 relay and the input backplane isolation relay Channel 25 c...

Страница 64: ...of the following messages will be briefly displayed when one of these keys is pressed NO SCAN CARD This message indicates that there are no switching modules or pseudocards installed both slots are e...

Страница 65: ...not a valid measurement channel The following actions will cause this error Trying to close a non measurement channel such as a backplane isolation channel a channel that sets the pole mode or a chan...

Страница 66: ...solation channels 124 and 125 and the 2 pole 4 pole channel 123 Figure 2 2 shows the backplane isolation channels and the 2 pole 4 pole channel for the Model 7700 Perform the following steps to open a...

Страница 67: ...nt channel with this command will result in error 222 Parameter data out of range b ROUTe CLOSe STATe clist This query returns a 0 open or 1 closed for every measurement channel specified the clist Fo...

Страница 68: ...OUTe OPEN ALL This command functions the same as the front panel OPEN key ALL menu option It simply opens all channels including non measurement channels installed in the mainframe Remote programming...

Страница 69: ...ps function DCI or ACI is selected and you attempt to close a system channel the message NO AMPS CHAN will be displayed briefly For remote programming error 222 Parameter data out of range is generate...

Страница 70: ...operation should be used to close channels on a non measure module For remote operation the ROUT MULT commands are used to close channels Front panel system single channel operation cannot be used to...

Страница 71: ...death Improper operation can also cause damage to the switching modules and external circuitry Multiple channel operation should be restricted to experienced test engineers who recognize the dangers...

Страница 72: ...fety issues improper use of multiple channel operation can result in corrupt measurements For example assume two Model 7700s installed in slots 1 and 2 and a 2 wire function selected If you use multip...

Страница 73: ...nels see CARD menu page 2 29 1 Press the CLOSE key and then use the or key to display the CLOSE MULTI message 2 Press ENTER to display the prompt to close a channel CLOSE MLT XXX 3 Using and key in th...

Страница 74: ...specified channel 1 Press the OPEN key The OPEN ALL message will be displayed 2 Press the or key to display the OPEN MULTI message 3 Press ENTER to display the prompt to open a channel OPEN MLT XXX 4...

Страница 75: ...stead be used and the integrity of the temperature reading will be questionable ERR annunciator on See Temperature measurements page 3 33 for details NOTE For RS 232 operation and in some cases GPIB o...

Страница 76: ...e CLOSe STATe clist This query returns a 0 open or 1 closed for every channel specified in the clist It is valid for both measurement and non measurement channels For example assume channel 125 is clo...

Страница 77: ...ement channel that is closed It will display channel 101 instead of channel 102 1 Use the ALL option for the OPEN key to open all channels in the mainframe Remote programming ROUT OPEN ALL 2 Press the...

Страница 78: ...o DMM Sense Channel 123 isolates channel 101 from channel 111 The Model 2700 will display the 1k reading for system channel 101 Remote programming ROUT CLOS 101 3 Using the MULTI option for the OPEN k...

Страница 79: ...lose the 2 pole 4 pole relay The Model 7700 is configured as two independent multiplexers by closing channel 23 As shown in Figure 2 8 the closed position of channel 23 isolates Multiplexer A channels...

Страница 80: ...urce each DUT is powered and measured separately Figure 2 9 shows the connections for this application The external source is connected to the Sense terminals of the switching module and DUT is connec...

Страница 81: ...to measure the temperature of DUT using a thermocouple with the INTernal or EXTernal reference junction selected The SIMulated reference junction will instead be used resulting in invalid readings The...

Страница 82: ...y ALL Press OPEN Remote programming ROUT OPEN ALL 2 Close channels 23 and 25 Front panel operation Press CLOSE Select MULTI Key in 123 Press ENTER Press CLOSE Select MULTI Key in 125 Press ENTER Remot...

Страница 83: ...e DUT 2 and then open channels 2 and 12 7 Test the remaining eight DUT in a similar manner That is close the appropriate channels for the DUT make the measurement and then open the channels 8 After th...

Страница 84: ...d set parameter values With the desired item option or setting displayed press the ENTER key to select it You can cancel a pending selection and exit the menu structure by pressing the EXIT key Press...

Страница 85: ...e relay setting and channels 124 and 125 connect input and sense to the DMM of the Model 2700 Figure 2 2 NOTE Some switching modules have analog outputs digital inputs and or digital outputs The value...

Страница 86: ...on measurement channels For details see Table 2 1 and related reference information ROUT MULT CLOS is used to return all closed channels measurement and non measurement For details see Table 2 2 and r...

Страница 87: ...operation The commands are summarized in Table 2 3 Details follow the table NOTE The relay closure count can be reset to zero For details see the Model 2700 Ser vice Manual Plug in module relay closu...

Страница 88: ...to the EEPROM on the card only at a user set time interval which is initially set to 15 minutes at the factory or whenever the counts are queried Valid intervals set in integer number of minutes are b...

Страница 89: ...Of the 22 measurement channels only one channel or channel pair can be closed at the same time When you close a channel or channel pair all other measurement channels will open The user has no control...

Страница 90: ...nnels 1 10 and channels 11 20 When a 2 wire function i e DCV is selected channel 23 opens 2 pole position to allow any of the 20 channels to be connected to the input backplane When a 4 wire function...

Страница 91: ...AMPS HI LO Sense HI LO Input Channel 23 2 Pole Open 4 Pole Closed See Note 3A 3A To Model 2700 Backplane Channel 25 See Note Backplane Isolation Channel 24 See Note Backplane Isolation Channels 23 and...

Страница 92: ...sic DC and AC voltage measurements Current measurements DCI and ACI Provides detailed information for making basic DC and AC current measurements Resistance measurements Provides detailed information...

Страница 93: ...ency measurements from 3Hz to 500kHz PERIOD Period measurements from 333ms to 2 s TEMP Temperature measurements from 200 C to 1820 C CONT Continuity testing using the 1k range CAUTION When using a swi...

Страница 94: ...g alligator clips spade lugs etc for hands off measurements Do not use test leads that decrease voltage spacing These diminish arc protection and create a hazardous condition WARNING For the front pan...

Страница 95: ...zeroing When autozero is disabled the offset gain and internal temperature measurements are not performed This increases the measurement speed However the zero gain and temperature reference points wi...

Страница 96: ...the positive going zero crossing of the power line cycle If the next trigger Trigger 2 occurs during the negative cycle then the measurement process also starts with the positive going zero crossing...

Страница 97: ...ation menu as explained in Section 7 For remote programming the clist parameter is used to configure scan channels Channel list parameter clist SCH where S Mainframe slot number 1 or 2 CH Switching mo...

Страница 98: ...e DCV measurements from 0 1 V to 1000V and ACV measurements from 0 1 V to 750V RMS 1000V peak DCV input resistance 100V and 1000V ranges 10M 100mV 1V and 10V ranges 10G 400pF or 10M ACV input impedanc...

Страница 99: ...le is less Exceeding the voltage rating of a switching module may cause damage and create a safety hazard NOTE When using the front panel inputs the INPUTS switch must be in the F out position For swi...

Страница 100: ...x 107V Hz Input Resistance 10M on 1000V and 100V ranges 10G on 10V 1V and 100mV ranges Caution Maximum Input 1000V peak A DCV Connections B ACV Connections F F F 500V PEAK FRONT REAR 3A 250V AMPS HI I...

Страница 101: ...channel 12 and so on As shown in Figure 3 3C one DC voltage source is connected to a primary channel i e 104 and the other source is connected to its paired channel i e 114 NOTE The ratio and channel...

Страница 102: ...ay cause damage to the switching module WARNING If both the front panel terminals and the switching module terminals are connected at the same time the test leads must be rated to the highest voltage...

Страница 103: ...e Therefore the AC coupled crest factor will differ from the DC coupled waveform The RMS function will calculate the RMS value based on the pulsed waveform with an average value of zero The reason to...

Страница 104: ...orms of crest factors up to 5 Figure 3 4 ACV measurements sine waves AC coupled RMS VP 0 VP 2 CF Sine Half Wave Rectified Sine VP 0 RMS 1 VAVG VAVG VP p VRMS VP CF 2 V 0 V AC coupled RMS V VP 1 1 p V...

Страница 105: ...oupled RMS VP 0 VP CF 1 Square VRMS VP 0 VP Rectified square AC coupled RMS VP 2 VRMS CF 2 VP 0 Pulse t T VRMS VP where D duty cycle D 1 D t T D 1 D 1 CF AC coupled RMS 0 AC coupled pulse AC coupled p...

Страница 106: ...2700 away from strong AC magnetic sources The voltage induced due to magnetic flux is proportional to the area of the loop formed by the input leads Therefore minimize the loop area of the input lead...

Страница 107: ...s with the input shorted This offset is caused by the offset of the TRMS converter This offset will not affect reading accuracy and should not be zeroed out using the REL feature The following equatio...

Страница 108: ...V and ACV page 3 7 Connections NOTE When using the front panel inputs the INPUTS switch must be in the F out position For switching modules it must be in the R in position WARNING To prevent electric...

Страница 109: ...amps measurement function by pressing DCI or ACI 3 Use the RANGE and keys to select a measurement range consistent with the expected current or press AUTO to select autoranging AUTO annunciator turns...

Страница 110: ...ent is disconnected from the power line and other equipment before replacing the AMPS fuse 1 Turn off the power and disconnect the power line and test leads 2 From the front panel gently push in the A...

Страница 111: ...For resistances 1k the 4 wire 4 measurement method should be used to cancel the effect of test lead and channel path resistances Offset compensated ohms OCOMP The presence of thermal EMFs voltages can...

Страница 112: ...B 4 Connections F F F 500V PEAK FRONT REAR 3A 250V AMPS HI INPUT LO SENSE 4 WIRE INPUTS 350V PEAK 1000V PEAK R Model 2700 F F F 500V PEAK FRONT REAR 3A 250V AMPS HI INPUT LO SENSE 4 WIRE INPUTS 350V...

Страница 113: ...el 1 is paired to channel 11 channel 2 is paired to channel 12 and so on Figure 3 9 2 and 4 connections for Model 7700 switching module Shielding To achieve a stable reading it helps to shield resista...

Страница 114: ...nstrument damage may occur Model 7700 switching module Do not apply more than 300V DC or 300V RMS 425V peak for AC waveforms between input high H or input low L or switching module damage may occur 5...

Страница 115: ...measurement the Model 2700 sources a current I and measures the voltage V The resistance R is then calculated R V I and the reading is displayed For offset compensated ohms two measurements are perfor...

Страница 116: ...higher range 4 Perform steps 4 through 8 of the Standard resistance measurements page 3 23 procedure NOTE The OCOMP annunciator will flash when the instrument is on an invalid range 100k through 100M...

Страница 117: ...asurement range For example for the 100 range the test current is 1mA Since the voltmeter of the Model 2700 has very high input impedance 10G virtually all the test current 1mA flows through the DUT F...

Страница 118: ...the Model 2700 VMEAS has very high input impedance 10G current through the voltmeter branch is insignificant and can be discounted Therefore as shown in Eq 1 ISOUR IREF IDUT 2700 VMEAS RREF RDUT ISOUR...

Страница 119: ...extra voltage measurement VLEAD to compensate for IR drop in the input test leads As stated in the specifications Appendix A to achieve rated accuracy the Input Hi and Input Lo test leads must have 1...

Страница 120: ...ghest ohm ranges open input lead detection is implemented in software Open circuit voltage for the 10M and 100M ranges is 7V For the 10M range the OVRFLW message trips when the open circuit voltage ri...

Страница 121: ...ection S W Detection Input Lo Sense Lo S W Detection I Source 100W DUT 1mA 6 6V Open Input Lead Sense HI Input HI Input Lo Sense Lo S W Detection I Source 100W DUT 1mA 15mV Open Sense Lead OVR FLW W 2...

Страница 122: ...he DUT When the Sense Lo lead opens the Sense Lo terminal will drift to 15mV and trip the OVRFLOW message Figure 3 13 Open Sense Lo lead detection 10M and 100M ranges Sense HI Input HI Input Lo Sense...

Страница 123: ...However this module can be configured for common side CSID 4 wire ohms measurements allowing up to 32 DUT to be tested With a 7701 module installed the 4 wire ohms mode can be selected using the follo...

Страница 124: ...ture changes the voltage changes The thermocouple voltage equates to a temperature reading This is the basic operation principle of the thermocouple NOTE The equation to calculate thermocouple tempera...

Страница 125: ...ragraphs NOTE When using multiple channel operation ROUT MULT command to connect a switching module input channel to the DMM the SIMulated reference junction will be used if the INTernal or EXTernal r...

Страница 126: ...urned off and a normal thermocouple temperature measurement is performed NOTE Channel average cannot be used with thermocouple temperature measurements if open thermocouple detection is enabled Thermi...

Страница 127: ...les are provided in Appendix F NOTE Only one USER RTD per scan list Connections NOTE When using the front panel inputs the INPUTS switch must be in the F out position For switching modules it must be...

Страница 128: ...11 channel 2 is paired to channel 12 and so on Keep in mind that a simulated reference junction i e ice bath can instead be used for these thermocouple temperature measurements Figure 3 14 Thermocoup...

Страница 129: ...hite French Yellow Black French Yellow Blue K U S Yellow Red R U S Black Red British Brown Blue British White Blue DIN Red Green DIN Red White Japanese Red White Japanese Red White French Yellow Purpl...

Страница 130: ...4 wire measurement The two input leads of the RTD are connected to a primary channel 1 through 10 while the two sense leads are connected to its paired channel 11 through 20 Channel 1 is paired to ch...

Страница 131: ...to configure thermocouple measurements are provided in Table 3 3 After pressing SHIFT and then SENSOR the menu starts at step 1 to select measurement units Each time you press ENTER to make a selectio...

Страница 132: ...ouple transducer 3 TYPE J K T E R S B or N Select thermocouple type 4 JUNC SIM INT or EXT Select the SIMulated INTernal or EXTernal reference junction SIM 000 C to 065 C 273K to 338K or 032 F to 149 F...

Страница 133: ...to the normal measurement state NOTE As shown in Table 3 6 you can select the USER sensor type but you cannot change the USER parameters from the front panel The parameters for the USER type can only...

Страница 134: ...sured 5 If using a switching module perform the following steps to close the desired channel Keep in mind that for 4 wire RTD measurements you will close the primary INPUT channel 1 through 10 The cha...

Страница 135: ...technique to measure frequency and period This method generates constant measurement resolution for any input frequency The multimeter s AC voltage measurement section performs input signal condition...

Страница 136: ...ure 3 17 FREQ and PERIOD connections for front panel inputs Model 7700 switching module Connections for the Model 7700 switching module are shown in Figure 3 18 For this 2 wire measurement channels 1...

Страница 137: ...o be measured CAUTION Do not apply more than the maximum input levels indicated in Figure 3 17 and Figure 3 18 or instrument damage may occur 5 If using a switching module perform the following steps...

Страница 138: ...be displayed If the reading is below 1100 it will be displayed If the reading is 1100 or above OPEN will be displayed NOTE The reading rate for continuity is fixed at FAST 0 01 PLC Limits and digital...

Страница 139: ...it is above the threshold level the instrument will not beep and either display the resistance reading or the message OPEN If the reading is below 1100 it will be displayed If the reading is 1100 or a...

Страница 140: ...mmands Commands1 Description Default Ref Select measurement function SENSe 1 Optional root command FUNCtion name clist Select measurement function name VOLTage DC VOLTage AC CURRent DC CURRent AC RESi...

Страница 141: ...65 C 32 to 149 F or 273 to 338 K 23 C d TEMPerature THERmistor NRf clist Set thermistor type in ohms NRf 1950 to 10050 5000 TEMPerature FRTD TYPE name clist Select FRTD type name PT100 D100 F100 PT39...

Страница 142: ...Sh Returns the last fresh reading string FETCh Return reading s READ Trigger and return reading s Channel list parameter clist SCH where S Mainframe slot number 1 or 2 CH Switching module channel numb...

Страница 143: ...mpensated ohms for that channel Error 700 Invalid function in scanlist will occur when trying to query the state of offset compensated ohms for that channel FRES OCOM ON 101 Details on scanning are pr...

Страница 144: ...VOLTage RANGe n clist These commands are used to specify the expected input level The instrument will then automatically select the most sensitive current or voltage threshold range g FREQuency APERtu...

Страница 145: ...n returning more than one reading the readings are automatically stored in the buffer In order to return multiple reading strings continuous initiation must be disabled INIT CONT OFF so that the sampl...

Страница 146: ...The following example can be run from the KE2700 Instrument Driver using the example named Ohmm in Table H 1 of Appendix H RST One shot measurement mode INIT CONT OFF FUNC FRES Select 4 function FRES...

Страница 147: ...anning is provided in Section 7 Measurement queries NOTE For more information on read commands see Section 8 Triggering Section 13 SCPI Signal Oriented Measurement Commands and Appendix D Signal Proce...

Страница 148: ...model to the idle layer equivalent to the ABORt command take the trigger model out of idle equivalent to the INIT command and return a reading equivalent to a FETCh query This command will always ret...

Страница 149: ...command for taking one shot measurements if the default settings for a measurement are appropriate and speed is not a requirement SENSe 1 DATA FRESh What it does This query is similar to FETCh in that...

Страница 150: ...s which would invalidate the old reading The CALC DATA LATest query is similar to the DATA LAT query but applies to readings that have math applied to them e g MX B scaling Examples One shot reading D...

Страница 151: ...Triggers reading GET is a GPIB general bus command SENSe DATA FRESh Enter reading One shot reading external trigger auto delay enabled RST INITiate CONTinuous OFF ABORt TRIGger SOURce EXTernal TRIGge...

Страница 152: ...rogramming Digits Provides details on selecting display resolution Includes the commands for remote programming Rate and bandwidth Provides details on integration rate and bandwidth for AC measurement...

Страница 153: ...LOW to be displayed FREQ and PERIOD Frequency measurements from 3Hz to 500kHz and period measurements from 2 s to 333 s can be made on the ACV ranges TEMP There is no range selection for temperature m...

Страница 154: ...o ranging is enabled the instrument automatically selects the best range to measure the applied signal Auto ranging should not be used when optimum speed is required Note that the AUTO key has no effe...

Страница 155: ...clist Control DCI auto range b ON or OFF ON CURRent AC RANGe n clist Select ACI range n 0 to 3 A 3 CURRent AC RANGe AUTO b clist Control ACI auto range b ON or OFF ON RESistance RANGe n clist Select...

Страница 156: ...ver using the example named MultiRange in Table H 1 of Appendix H Example 1 The following commands select range for DCV 2 and DCI VOLT RANG 0 5 Select 1V range for DCV RES RANG 2e3 Select 10k range fo...

Страница 157: ...et of digits for DCV n 4 to 7 7 VOLTage AC DIGits n clist Set of digits for ACV n 4 to 7 6 CURRent DC DIGits n clist Set of digits for DC1 n 4 to 7 7 CURRent AC DIGits n clist Set of digits for ACI n...

Страница 158: ...nds in Table 4 3 each mainframe input function can have its own unique digits setting Digits programming examples NOTE The following examples can be run from the KE2700 Instrument Driver using the exa...

Страница 159: ...time 0 1 PLC from the front panel 0 01 PLC from the bus results in increased reading noise and fewer usable digits while the slowest integration time 5 PLC from the front panel 50 PLC from the bus pro...

Страница 160: ...or medium speed the other functions will also set to medium speed For remote programming each function can have its own unique rate setting 0 01 to 50 or 60 PLC NOTE Rate cannot be set for continuity...

Страница 161: ...cies is simply measured at 1 PLC 16 6ms For remote programming the integration rate can be set from 0 01 PLC to 50 or 60 PLC Table 4 4 lists the front panel bandwidth settings for the AC measurement f...

Страница 162: ...ture APERture n clist Set rate for TEMP in secs n x to 13 Note 4 Bandwidth commands SENSe 1 Optional root command VOLTage AC DETector BANDwidth NRf clist Set AC bandwidth for ACV in Hertz NRf 3 to 3e5...

Страница 163: ...y the frequency of the input signal The instrument will automatically set the bandwidth as follows NRf 3 to 29 3Hz to 300kHz 30 to 299 30Hz to 300kHz 300 to 300e3 300Hz to 300kHz NOTE A rate command N...

Страница 164: ...bilize noisy measurements The displayed stored or trans mitted reading is a windowed average of a number of reading conversions from 1 to 100 The filter setup is remembered and can be unique for each...

Страница 165: ...r channels are not averaged with the present channel The stack is then cleared and the process starts over see Figure 4 2B NOTE The moving filter cannot be used when scanning If a scan channel is set...

Страница 166: ...1 Conversion 12 11 10 9 8 7 6 5 4 3 Conversion Average Reading 3 Conversion 11 10 9 8 7 6 5 4 3 2 Conversion Average Reading 2 A Type Moving Average Readings 10 Conversion 10 9 8 7 6 5 4 3 2 1 Conver...

Страница 167: ...ing the window can be set to any value from 0 01 to 10 or NONE For voltage current and resistance the filter window is expressed as a percent of range For example on the 10V range a 10 window means th...

Страница 168: ...1 A1 A1 A1 A1 Rdg 1 A2 A1 A1 A1 A1 Rdg 2 A3 A2 A1 A1 A1 Rdg 3 A4 A3 A2 A1 A1 Rdg 4 A5 A4 A3 A2 A1 Rdg 5 A6 A5 A4 A3 A2 Rdg 6 B1 B1 B1 B1 B1 Rdg 7 B2 B1 B1 B1 B1 Rdg 8 B3 B2 B1 B1 B1 Rdg 9 B4 B3 B2 B1...

Страница 169: ...er of readings to filter 1 to 100 and press ENTER 5 Use the or key to display the desired filter type moving or repeating and press ENTER The filter turns on and the instrument returns to the normal m...

Страница 170: ...The window setting is ignored effectively set to NONE and if the moving filter is selected the filter will not enable when the scan is run For the advanced scan filter state on or off and count can be...

Страница 171: ...ptional root command VOLTage AC AVERage TCONtrol name Select filter type name MOVing or REPeat Note 2 VOLTage AC AVERage WINDow NRf Set filter window in NRf 0 to 10 0 1 VOLTage AC AVERage COUNt n clis...

Страница 172: ...Note 2 TEMPerature AVERage WINDow NRf Set filter window in NRf 0 to 10 0 1 TEMPerature AVERage COUNt n clist Specify filter count n 1 to 100 10 TEMPerature AVERage STATe b clist Enable or disable the...

Страница 173: ...ing filter CURR AVER WIND 0 01 Set filter window to 0 01 CURR AVER COUN 10 Set to filter 10 readings CURR AVER ON Enable filter NOTE The following example can be run from the KE2700 Instrument Driver...

Страница 174: ...1 X Includes the commands for remote programming Ratio and channel average Explains how to use these calculations to display the ratio or average of two switching channels dB Explains how to use remo...

Страница 175: ...el value does not cause an overflow condition but it also does not increase the maximum allowable input for that range For example on the 10V range the Model 2700 still overflows for a 12V input NOTE...

Страница 176: ...e provided in Section 7 For an advanced scan the following general procedure shows how to configure a scan channel to use rel 1 While in the normal measurement state select the appropriate function an...

Страница 177: ...erence ACQuire clist Use input signal as rel value Rel commands for ACV SENSe 1 Optional root command VOLTage AC REFerence n clist Specify rel value n 757 5 to 757 5 V 0 VOLTage AC REFerence STATe b c...

Страница 178: ...e 1 Optional root command FREQuency REFerence n clist Specify rel value n 0 to 1 5e7 Hz 0 FREQuency REFerence STATe b clist Enable disable rel b ON or OFF OFF FREQuency REFerence ACQuire clist Use inp...

Страница 179: ...e for the specified function while the ACQuire command uses the input signal as the rel value The ACQuire command is typically used to zero the display For example if the instrument is displaying a 1...

Страница 180: ...el and use a 1V rel value when it is scanned NOTE The following example can be run from the KE2700 Instrument Driver using the example named Relative2 in Table H 1 of Appendix H FUNC VOLT 101 Select D...

Страница 181: ...rious instrument operations including Math are performed on the input signal in a sequential manner See Signal processing sequence page D 2 for details It includes flowcharts showing where in the proc...

Страница 182: ...position and the and keys increment decrement the digit value To change range place the cursor on the multiplier and use the and keys m 0 001 1 K 1000 and M 1 000 000 With the cursor on the polarity...

Страница 183: ...display PERCENT and press ENTER to display the present reference value REF 1 000000 factory default 3 Key in the reference value The and keys control cursor position and the and keys increment decrem...

Страница 184: ...ed the following conductance reading will be displayed 0 4 R Reciprocal 1 X configuration 1 Press SHIFT and then MATH to display the math menu 2 Press the RANGE or key to display 1 X and press ENTER T...

Страница 185: ...odel 7700 switching module channels 21 and 22 are available for DCI and ACI Channels 1 through 20 are available for all other functions 4 If using a switching module REAR inputs selected use the or ke...

Страница 186: ...mX b m factor NRf 4294967295 to 4294967295 1 CALCulate 1 KMATh MBFactor NRf clist Set mX b b factor NRf 4294967295 to 4294967295 0 CALCulate 1 KMATh MUNits char clist Set mX b units see Setting mX b u...

Страница 187: ...he PERCent ACQuire command When a reference value is set using PERCent NRf the PERCent query command returns the programmed value When reference is set using ACQuire the PERCent query command returns...

Страница 188: ...t mX b calculation CALC KMAT MMF 2 Set m factor to 2 CALC KMAT MBF 100 Set b factor to 100 CALC STAT ON Enable math calculation ROUT CLOS 101 Close channel 101 CALC DATA Read mX b result for channel 1...

Страница 189: ...d the Model 2700 measures the closed primary channel It then opens the primary channel and closes and measures the paired channel Ratio or channel average is then calculated from the two readings and...

Страница 190: ...yed readings are the result of the channel average calculation To disable channel average again press SHIFT and then CH AVG 5 When finished there are two ways to disable the calculation Press the OPEN...

Страница 191: ...nel average Details to configure and run a scan are provided in Section 7 Advanced scan configuration notes 1 When a calculation ratio or channel average is enabled for a primary scan channel the foll...

Страница 192: ...ails This delay cannot be set from the front panel The 0 5s default delay keeps the relays from cycling too fast Setting a shorter delay may shorten the life of the relays It does not matter which of...

Страница 193: ...DCV function ROUT CLOS 102 Close channel 102 RAT ON Enable the ratio calculation READ Read the result of the calculation Example 2 The following command sequence configures channels 103 and 105 for t...

Страница 194: ...r dB has been selected dB has REL applied to it NOTE The dB calculation takes the absolute value of the ratio VIN VREF The largest negative value of dB is 160dB This will accommodate a ratio of VIN 1...

Страница 195: ...1 ACV dB commands UNITs VOLTage AC name Select ACV measurements name V or DB V UNITs VOLTage AC DB REFerence n Set reference in volts n 1e 7 to 1000 1 Channel list parameter clist SCH where S Mainfra...

Страница 196: ...H FUNC VOLT Select DCV function UNIT VOLT DB Select DCV dB UNIT VOLT DB REF 1V Set dB reference to 1V Example 2 The following command sequence configures channels 101 and 105 of the Model 7700 to perf...

Страница 197: ...5 24 Rel Math Ratio Channel Average dB Model 2700 Multimeter Switch System User s Manual...

Страница 198: ...how to store and recall readings and discusses the various statistics available on buffer data including minimum and maximum values average mean standard deviation and peak to peak values Remote prog...

Страница 199: ...a sequential manner See Signal processing sequence page D 2 for details It includes flowcharts showing where in the processing sequence that buffer operations occur Front panel buffer Auto clear With...

Страница 200: ...ear to change the buffer size The auto clear setting on or off is not affected by SYSTem PRESet or RST front panel or remote operation However front panel FACTory defaults enables buffer auto clear En...

Страница 201: ...the buffer and one hour later you store 10 more readings The timestamps for all 20 readings are referenced to the first reading Therefore the timestamp for the 11th reading 10 is one hour 3600 second...

Страница 202: ...T and then SETUP 2 Use the and keys to display SET DATE and press ENTER to display the date in the month day year format 3 Use the edit keys and to set the date month day year and press ENTER Selectin...

Страница 203: ...ts to overwrite old reading data see TRACe FEED CONTrol command in Table 6 1 Recalling readings Readings stored in the buffer are displayed by pressing the RECALL key The readings are positioned at th...

Страница 204: ...p Delta Timestamp RDG NO 1 Reading Value Absolute Timestamp Delta Timestamp STD DEV Standard Deviation Value No Timestamp Average Average Value No Timestamp Peak to Peak Peak to Peak Value No Timestam...

Страница 205: ...equation is used to calculate mean where y is the average Xi is a stored reading n is the number of stored readings Standard deviation This mode displays the standard deviation of buffered readings Th...

Страница 206: ...are listed in Table 6 1 Details on these commands follow the table NOTE Optional command words and most queries are not included in Table 6 1 The unabridged tables for all SCPI commands are provided i...

Страница 207: ...eadings to be returned start starting point count number of readings j TRACe NEXT Query buffer location for next stored reading j TRACe NOTify NRf Specify number of stored readings that will set Trace...

Страница 208: ...turned off When TRAC CLE is sent while displaying stored readings the message BUF CLEARED is briefly displayed and the instrument returns to the normal measurement state TRACe CLEar AUTO With auto cle...

Страница 209: ...tore readings in the buffer TRACe FEED cannot be set to NONE TRACe FEED CONTrol Selecting NEXT enables the buffer After the specified number of readings buffer size are stored buffer operation disable...

Страница 210: ...ocation for the next stored reading TRACe NEXT Query buffer location for next stored reading Assume that the above query returned value 37 Now you can use that value as the count parameter for the fol...

Страница 211: ...BSolute or DELTa timestamp as set by the TRACe TSTamp FORMat command FORMat ELEMents READing CHANnel UNITs RNUMber TSTamp LIMits Choose the elements to be outputted with each DATA or each buffer readi...

Страница 212: ...han 1000 readings the CALCULATING message will flash to indicate that the Model 2700 is busy While busy with the calculation remote programming commands will not execute NOTE Use OPC or OPC with CALC2...

Страница 213: ...6 16 Buffer Model 2700 Multimeter Switch System User s Manual...

Страница 214: ...a simple scan or an advanced scan Covers other scan options including delay monitor auto configuration saving setups and auto scan Scan operation Provides the step by step procedures to perform a bas...

Страница 215: ...This allows the user to configure a scan and exercise its operation before the switching module is installed in the Model 2700 Use the following commands to install 7700 pseudocards in empty slots SY...

Страница 216: ...y a sequential scan can be configured from the front panel For a sequential scan the scan proceeds from the lowest numbered channel to the highest For example assume channels 101 102 105 108 and 109 a...

Страница 217: ...ulations also use paired channels The scan process is to 1 open any closed channels 2 close the primary displayed channel and perform a measurement 3 open the primary channel 4 close the paired channe...

Страница 218: ...refer to Figure 7 1 for STEP operation and Figure 7 2 for SCAN operation Figure 7 1 Trigger model with STEP function Enable Scan Control Source Immediate External Timer Event Detection Output Trigger...

Страница 219: ...l Timer Manual Bus Event Detection Another Scan Trigger Counter Yes No Close First Chan in List Open Last Chan Close Next Chan in List Ratio Chan Average Delay Measurement Process Device Action Output...

Страница 220: ...n the scan list is measured the Model 2700 outputs a trigger pulse If programmed to again scan the channels in the scan list the Model 2700 will wait at the control source for another trigger event Af...

Страница 221: ...iming between scans It has no effect on the timing between scanned channels External trigger control source Pressing the EX TRIG key places the instrument in the external trigger mode TRIG annunciator...

Страница 222: ...oo fast The default delay period is 0 5 seconds but can be set from 0 to 999999 999 seconds using remote programming Ratio and channel average are covered in Section 5 NOTE The Ratio Chan Average Dela...

Страница 223: ...s equal to the scan list length For example if channels 101 102 and 103 are programmed to be scanned the Sample Count is 3 Output trigger STEP operation After each channel is scanned an output trigger...

Страница 224: ...setup As explained in Trigger models page 7 4 there is a user set delay auto or manual that is in effect for both the simple and advanced scan Channel setup considerations Rel In order to use an acqu...

Страница 225: ...en The saved setup is still retained in memory and can be restored when the matching switching module is later installed The displayed front panel CONFIG menu operates differently from other menus whe...

Страница 226: ...starting channel MIN CHAN and an ending channel MAX CHAN for the scan These settings determine the number of channels in the scan For example if you set MIN CHAN to 101 and MAX CHAN to 110 there will...

Страница 227: ...scan list When you enter the channel setup menu the displayed information indicates the present setup for the selected channel The position of the decimal point in the SETUP message indicates present...

Страница 228: ...7700 example If you press DCV for channel 101 channels 101 through 120 will assume the DCV setup Note that channels for slot 2 are not affected When you press the 4 function key for a primary channel...

Страница 229: ...unction Available channels that follow will assume the same setup Note however that channels for slot 2 are not affected NOTE For the Model 7700 DCI and ACI cannot be selected for channels 101 through...

Страница 230: ...splay TIMER NO which is the factory and RST default and press ENTER To use the timer use the or key to display TIMER YES and press ENTER The timer interval is displayed in the hour minute second forma...

Страница 231: ...TO key sets the manual delay to 0 001 sec 4 With the desired manual delay displayed press ENTER For remote programming the TRIGer DELay NRf and TRIGger DELay AUTO b commands are used to set the delay...

Страница 232: ...el must be a channel that is in the scan list Method 1 1 Use the CLOSE key or the and keys to close the channel that you want to be the monitor 2 Press SHIFT and then MONITOR MON annunciator turns on...

Страница 233: ...present setting N or Y and press the or key to change the setting 4 Press ENTER to return to the normal measurement state NOTES Auto channel configuration cannot be enabled if there is a non scan chan...

Страница 234: ...auto scan 1 While in the normal measurement state press SHIFT and then SETUP 2 Use the and keys to display the auto scan AUTOSCAN setting N no or Y yes 3 To change the setting press to place the curs...

Страница 235: ...press STEP or SCAN the scan will continue starting with the next channel 5 With reading count set to infinite the scan will keep repeating NOTE While the scan is enabled STEP or SCAN annunciator on m...

Страница 236: ...anned the first channel in the scan list closes The reading count determines how many channel measurements will be performed during the scan sequence If the reading count is greater than the scan list...

Страница 237: ...gger the start of the scan Perform the following steps to run a monitor scan NOTE The last enabled scan function STEP or SCAN will be used for the monitor scan 1 Perform Step 1 and Step 2 of the Advan...

Страница 238: ...MONitor POINts command to specify the number of channels to scan Table 7 1 4 While in the normal measurement state select and enable the monitor channel as explained in Scan configuration Monitor chan...

Страница 239: ...ate one scan cycle include INITiate Initiate one scan cycle READ Initiate one scan cycle and request sample readings More information on using these commands is provided by Reference c that follows Ta...

Страница 240: ...ands to set range digits and rate would generate error 700 Invalid function in scanlist Buffer For front panel scanning the reading count specifies the number of readings to store in the buffer For re...

Страница 241: ...e MONitor POINts NRf Specify number of channels to scan NRf 2 to 55000 Note 3 d ROUTe MONitor STATe b Enable disable monitor b ON or OFF OFF ROUTe MONitor DATA Returns the most recent monitor reading...

Страница 242: ...ple count INITiate CONTinuous b Enable disable continuous initiation b ON or OFF f INITiate Initiate one scan cycle f READ Initiate one scan cycle and request sample readings f Buffer commands TRACe D...

Страница 243: ...nnel 110 then proceeds backward to channel 101 NOTES Non sequential scanning is only intended to be performed using remote programming Unexpected results may occur if a non sequential scan is run from...

Страница 244: ...or channel For immediate the IMMediate command must be the only parameter in the list To use reading limits each limit must be separated by a comma Examples ROUT SCAN TSO IMM Start scan when it is ena...

Страница 245: ...ITiate CONTinuous INITiate and READ In order to initiate a single scan cycle using INITiate or READ continuous initiation must be disabled If you send INIT or READ with continuous initiation enabled e...

Страница 246: ...to display RESTORE FACT and then press ENTER to select it External trigger scan For this example an external instrument is used to trigger the start of the 2 channel scan Trigger pulse requirements an...

Страница 247: ...scan is enabled channel 101 closes and the Model 2700 waits for an external trigger When the trigger is received channels 101 and 102 are measured Operation then returns to the control source where i...

Страница 248: ...TEMP 101 Configure temperature SHIFT SENSOR Select thermocouple sensor SENS TCOUPLE TEMP TRAN TC 101 Select type K thermocouple TYPE K TEMP TC TYPE K 101 Select internal reference junction JUNC INT T...

Страница 249: ...A simplified model of monitor scan operation is shown in Figure 7 5 while the procedure steps and programming commands are listed in Table 7 3 In Figure 7 5 notice that there are two modes of operati...

Страница 250: ...r s Manual Scanning 7 37 Figure 7 5 Monitor scan example 30 C 4 Measurements Measure TEMP Close Monitor Channel 101 No Yes Measure Open Last Chan Close Next Chan Close First Channel Return to Monitor...

Страница 251: ...RSEL INT 101 b Set and enable high limit 1 Set limit to 30 SHIFT LIMITS HI1 30 00000 CALC3 LIM1 UPP 30 101 Enable on limit SHIFT OFF ON LIMITS ON CALC3 LIM1 STAT ON 101 Close channel 101 ROUT CLOS 10...

Страница 252: ...Explains the Reading Hold feature which is used to screen out readings that are not within a specified reading window External triggering Explains external triggering which allows the Model 2700 to t...

Страница 253: ...trol triggering NOTE For scanning the trigger model has additional control blocks such as a Timer These are described in Section 7 Figure 7 1 and Figure 7 2 The complete trigger model which is based o...

Страница 254: ...20 When scanning the unit is considered idle at the end of a scan operation when the reading for the last channel remains displayed To restore triggers press SHIFT and then HALT See Section 7 for deta...

Страница 255: ...n scanning the nominal delay will be long enough to allow each switch ing module channel relay to settle before making the measurement When scanning the auto delay times in Table 8 1 are valid for all...

Страница 256: ...a moving average filter is reached After a reading Rdg is procured operation proceeds to Hold Hold The Hold feature is used to screen out reading anomalies When enabled the user selects a window and c...

Страница 257: ...ues When a hold reading is acquired an audible beep is sounded if enabled and the reading is considered a true measurement The reading is held on the display until an out of window reading occurs to r...

Страница 258: ...G key to trigger a single reading Pressing the EX TRIG key again toggles back to continuous triggers The Model 2700 uses two lines of the TRIG LINK rear panel connector as External Trigger EXT TRIG in...

Страница 259: ...s For the Model 2700 to respond to external triggers the trigger model must be configured for it Figure 8 4 Trigger link input pulse specifications EXT TRIG TRIG LINK Pinout 1 2 3 4 5 6 7 8 Pin 2 Exte...

Страница 260: ...t can be used to trigger other instruments The specifications for this trigger pulse are shown in Figure 8 5 Typically you would want the Model 2700 to output a trigger after the settling time of each...

Страница 261: ...gger Link either IN or OUT of the Model 7002 Note that with the default trigger settings on the Model 7002 line 1 is an input and line 2 is an output This complements the trigger lines on the Model 27...

Страница 262: ...S232 CARD 1 CARD 2 CARD 3 CARD 4 CARD 5 CARD 6 CARD 7 CARD 8 CARD 9 CARD 10 INTERCONNECTION INST ALLA TION AND REMOV AL OF CARDS BY QUALIFIED SERVICE PERSONNEL ONL Y WARNING NO INTERNAL OPERA TOR SERV...

Страница 263: ...or triggering example A Pressing EX TRIG on the Model 2700 places it at point A in the flowchart where it is waiting for an external trigger B Pressing STEP on the Model 7002 takes it out of the idle...

Страница 264: ...is triggers the Model 2700 to measure the next DUT The process continues until all 400 channels are scanned measured and stored in the buffer External triggering with BNC connections An adapter cable...

Страница 265: ...enever operation is at the top of the trigger model As shown in Figure 8 10 initiation needs to be satisfied to take the instrument out of idle While in the idle state the instrument cannot perform an...

Страница 266: ...efore operation will immediately leave the idle state when it is sent The RCL command will do the same if INITiation CONTinuous ON is a user saved default RST disables continuous initiation Therefore...

Страница 267: ...NIT IMM or INIT CONT ON No Yes Idle and Initiate Trigger Source Immediate Trigger Source External Trigger Source Timer Trigger Source Manual Trigger Source BUS Trigger Delay n Trigger Delay AUTO b Ano...

Страница 268: ...delay is controlled by the user set Delay period The Timer interval can be set from 0 to 999999 999 seconds The timer source is only available during scan operation The timer resets to its initial sta...

Страница 269: ...te one trigger cycle b INITiate CONTinuous b Enable disable continuous initiation ON or OFF Note 1 c FETCh Request the last reading s d READ Perform an ABORt INITiate and a FETCh d TRIGger SOURce name...

Страница 270: ...These commands are also explained in Section 3 Section 13 and Appendix D e TRIGger SOURce name With the timer control source selected use the TRIGger TIMer command to set the interval f DELay AUTO b T...

Страница 271: ...triggers and stores in the buffer 10 readings Note that in order to send the readings to the computer you must address the Model 2700 to talk after sending READ RST Restore RST defaults TRAC CLE Clear...

Страница 272: ...utputs respond to the results of limit tests Remote programming limits and digital output Summarizes the commands to perform limit tests and control the digital I O port Application sorting resistors...

Страница 273: ...following limits which are the factory defaults Limit 1 HI1 1V and LO1 1V Limit 2 HI2 2V and LO2 2V Keep in mind that a limit value for Limit 2 does not have to exceed the Limit 1 value For example Li...

Страница 274: ...eper A beeper is also available for limit testing There are three beeper options NEVER OUTSIDE and INSIDE These options are explained as follows NEVER With this option the beeper is disabled OUTSIDE W...

Страница 275: ...he cursor on the range designator each press of or will increase or decrease the reading by a factor of 10 3 Key in the low limit for Limit 1 LO1 and press ENTER 4 Key in the high limit for Limit 2 HI...

Страница 276: ...s used to enable or disable Trigger In Trigger In is enabled by leaving pin 8 open or pulling it high 5V Trigger In is disabled by setting pin 8 low 0V NOTE External triggering is covered in Section 8...

Страница 277: ...tic for one digital output All five digital output circuits are identical Figure 9 3 Digital I O port simplified schematic The five digital output lines pins 1 through 5 are controlled by limit operat...

Страница 278: ...lse option Pulse option is available for the digital outputs When enabled an output line will pulse high or low depending on the logic sense setting for each reading that reaches or exceeds the limit...

Страница 279: ...d or relay coils To use these fly back diodes connect the external supply voltage to pin 7 of the digital I O port Make sure the external supply voltage is between 5V and 33V and the current required...

Страница 280: ...lling externally powered relays 4 75k Pull Up Resistor Pin 9 Digital Ground Digital Output Pin 7 Diode Clamp Relay Coil Relay Coil External Power 5V to 33V External Power 5V to 33V Model 2700 Transist...

Страница 281: ...gic high output 3 75V When the output line goes low the transistor turns on transistor switch closed to route current to digital ground As a result a low logic output 0V is provided at the output If t...

Страница 282: ...then OUTPUT 2 If the digital output is already on DOUTPUT ON proceed to step 3 Otherwise press to move the cursor to the right press or key to display ON and press ENTER 3 Use the key to display the m...

Страница 283: ...ion Def Ref Limit 1 commands CALCulate3 LIMit1 UPPer NRf clist Set HI1 limit NRf 4294967295 to 4294967295 1 CALCulate3 LIMit1 LOWer NRf clist Set LO1 limit NRf 4294967295 to 4294967295 1 CALCulate3 LI...

Страница 284: ...exceeds the high or low limit the HIGH or LOW annunciator will turn on and the number 2 will be displayed NOTE When limits are disabled from the front panel both Limit 1 and Limit 2 disable for remote...

Страница 285: ...r a limit the fail indication clears when instrument operation enters the idle state With auto clear disabled the fail indication will remain until it is cleared by the CLEar command Limits and digita...

Страница 286: ...tors that exceed 5 tolerance The digital outputs of the Model 2700 can be used to further automate the test system by controlling a compatible component handler to perform the binning operations Limit...

Страница 287: ...100 5 99 95 The limits are illustrated in Figure 9 7 Figure 9 7 Limits to sort 100 resistors 1 5 and 5 Front Panel Operation For front panel operation the INSIDE beeper mode must be used A normal pitc...

Страница 288: ...ble 9 2 CLEar command Digital outputs With the digital outputs of the Model 2700 enabled the digital outputs will respond as follows for each resistor reading Limit 1 result Limit 2 result Resistor to...

Страница 289: ...9 18 Limits and Digital I O Model 2700 Multimeter Switch System User s Manual...

Страница 290: ...address selection and bus connections General bus commands Describes general bus commands used for fundamental GPIB control Front panel GPIB operation Summarizes GPIB error messages status indicators...

Страница 291: ...led from the front panel However once it is installed you can take the Model 2700 out of remote and use the front panel When the instrument is turned off the pseudocard will be lost uninstalled Autoze...

Страница 292: ...e set separately NOTE Do not confuse function setups with scan channel setups For scan channels separate settings for digits rate and filter configuration can be set from either the front panel or rem...

Страница 293: ...2 1992 and defines a standard set of commands to control every programmable aspect of an instrument Selecting GPIB and setting primary address The Model 2700 is shipped from the factory with the GPIB...

Страница 294: ...0 1 IEEE 488 connector To allow many parallel connections to one instrument stack the connectors Two screws are located on each connector to ensure that connections remain secure Present standards cal...

Страница 295: ...system Figure 10 2 IEEE 488 connections To avoid possible mechanical damage stack no more than three connectors on any one unit NOTE To minimize interference caused by electromagnetic radiation use on...

Страница 296: ...equipped with an IEEE 488 style connector but a few may require a different type of connecting cable See your controller s instruction manual for information about properly connecting to the IEEE 488...

Страница 297: ...ontroller to place the Model 2700 in the local talker listener idle states The unit responds to the IFC command by canceling front panel TALK or LSTN lights if the instrument was previously placed in...

Страница 298: ...ngs and stored data SDC selective device clear The SDC command is an addressed command that performs essentially the same function as the DCL command However since each device must be individually add...

Страница 299: ...s on When the instrument is in remote all front panel keys except for the LOCAL key are locked out When REM is turned off the instrument is in the local state and front panel operation is restored NOT...

Страница 300: ...ive For safety reasons the OUTPUT key will still be active in LLO Programming syntax The information in this section covers syntax for both common commands and SCPI com mands For information not cover...

Страница 301: ...on format This parameter is a number that can be expressed as an integer e g 8 a real number e g 23 6 or an exponent 2 3E6 Example SYSTem KEY 11 Press EXIT key from over the bus n Numeric value A nume...

Страница 302: ...ommands have a query form TRIGger TIMer Queries the timer interval Most commands that require a numeric parameter n can also use the DEFault MINimum and MAXimum parameters for the query form These que...

Страница 303: ...e the following rules to determine the short form version of any SCPI command If the length of the command word is four letters or less no short form version exists Example auto auto These rules apply...

Страница 304: ...the root command stat and moves down the command levels until the command is executed Multiple command messages You can send multiple command messages in the same program message as long as they are...

Страница 305: ...Executing a command at a higher level requires that you start over at the root command Using common and SCPI commands in the same message Both common commands and SCPI commands can be used in the same...

Страница 306: ...e order the query commands were sent and are separated by semicolons Items within the same query are separated by commas The following example shows the response message for a program message that con...

Страница 307: ...t You can break an RS 232 transmission of buffer readings by pressing LOCAL and then EXIT The next command to send buffer data i e TRACe DATA will start at the beginning rather than where the transmis...

Страница 308: ...g commands A list of the slowest responding commands and details on OPC and OPC are provided in Section 12 XonXoFF is the FACT and RST default flow control setting If NONE is the selected flow control...

Страница 309: ...rol press ENTER and proceed to step 5 Otherwise press the key to place the cursor on the flow control setting use the or key to display the alternate flow control setting and then press ENTER 5 To ret...

Страница 310: ...Model 2700 Multimeter Switch System User s Manual Remote Operations 10 21 Figure 10 4 RS 232 interface connector 1 2 3 4 5 6 7 8 9 Rear Panel Connector...

Страница 311: ...Pin number Description 1 No connection 2 TXD transmit data 3 RXD receive data 4 No connection 5 GND signal ground 6 Not used 7 RTS ready to send1 8 CTS clear to send1 9 No connection 1 CTS and RTS ar...

Страница 312: ...er in the status structure Status byte and service request SRQ Explains how to program the Status Byte to generate service requests SRQs Shows how to use the serial poll sequence to detect SRQs Status...

Страница 313: ...t as programmed by the user the RQS MSS bit will set to indicate that an SRQ has occurred Status register sets A typical status register set is made up of a condition register an event register and an...

Страница 314: ...er Buffer Notify Questionable Event Enable Register Questionable Condition Register Questionable Event Register 0 2 3 5 6 Cal 7 9 10 11 12 13 15 1 Temp Warn 0 2 3 5 6 Cal 7 9 10 11 12 13 15 1 Temp War...

Страница 315: ...iption Notes Reset registers CLS Reset all bits of the following event registers to 0 1 Standard Event Register Operation Event Register Measurement Event Register Questionable Event Register STATus P...

Страница 316: ...igure 11 2 indicate the binary parameter value For example if you wish to set bits B4 B3 and B1 the binary value would be 11010 where B4 1 B3 1 B1 1 and all other bits are 0 The binary value is then c...

Страница 317: ...and B4 are set 1 Status byte and service request SRQ Service request is controlled by two 8 bit registers the Status Byte Register and the Service Request Enable Register Figure 11 3 shows the structu...

Страница 318: ...ge is present in the Error Queue Bit B3 Questionable Summary Bit QSB Set summary bit indicates that an enabled questionable event has occurred Bit B4 Message Available MAV Set summary bit indicates th...

Страница 319: ...1 will set bit B6 and generate an SRQ service request In your test program you can periodically read the Status Byte to check if an SRQ has occurred and what caused it If an SRQ occurs the program can...

Страница 320: ...line 3 bits B2 EAV and B6 MSS of the Status Byte Register set to 1 The last command reads the Status Byte Register Keep in mind that you have to address the Model 2700 to talk after sending a query co...

Страница 321: ...ion calls that are equivalent to the initialize transmit send srq and spoll calls used below SRQ when buffer fills with 500 1000 1500 and 1750 readings The following program will store 2000 readings i...

Страница 322: ...s Disable standard events CALL send addr sre 1 status Enable measurement events CALL send addr init status Start measure store process N 0 Initialize quarter buffer counter WaitSRQ WHILE srq 0 WEND Wa...

Страница 323: ...t indicates that all pending selected device operations are completed and the Model 2700 is ready to accept new com mands This bit only sets in response to the OPC query command See Section 12 for det...

Страница 324: ...setups page 1 20 Error 523 Card hardware error Communication with the microprocessor on a switching module card has been lost Error 524 Unsupported card detected The Model 2700 has detected an instal...

Страница 325: ...Filt Set bit indicates that the filter has settled or the filter is disabled Bit B9 Not used Bit B10 Idle State Idle Set bit indicates the Model 2700 is in the idle state Bits B11 through B15 Not use...

Страница 326: ...ement event register on page 11 20 Bit B6 Buffer Notify BN Set bit is a notification that the user specified number of readings have been stored in the buffer The TRACe NOTify command specifies the nu...

Страница 327: ...BOF B10 BF B9 BHF B8 BAV B7 BN B6 RAV B5 HL2 B4 LL2 B3 HL1 B2 LL1 B1 ROF B0 B15 ML B14 BTF B13 BQF B12 HL B11 BOF B10 BF B9 BHF B8 BAV B7 BN B6 RAV B5 HL2 B4 LL2 B3 HL1 B2 LL1 B1 ROF B0 OR To Measurem...

Страница 328: ...will clear after successful calibration of the instrument Bits B9 through B13 Not used Bit B14 Command Warning Warn Set bit indicates that a Signal Oriented Measurement Command parameter has been ign...

Страница 329: ...t occurs the appropriate event register bit sets to 1 The bit remains latched to 1 until the register is reset Reading an event register clears the bits of that register CLS resets all four event regi...

Страница 330: ...s page 11 5 and Reading registers page 11 6 NOTE The bits of any enable register can be reset to 0 by sending the 0 parameter value with the appropriate enable command i e STATus OPERation ENABle 0 Ta...

Страница 331: ...ter STAT PRES Clear measurement event enable register STAT MEAS ENAB 32 Enable RAV bit B5 of the measurement event register INIT Trigger one measurement STB Read status byte register CLS and STAT PRES...

Страница 332: ...he standard event register TRAC POIN 500 Sets buffer size to 500 readings TRAC FEED SENS Sets to store raw readings TRIG COUN 500 Sets 2700 to perform 500 measurements TRAC FEED CONT NEXT Enables buff...

Страница 333: ...ppropriate query is sent Error queue The Error Queue holds error and status messages When an error or status event occurs a message that defines the error status is placed in the Error Queue When a me...

Страница 334: ...m entering the Error Queue send the enable command along with the null list parameter as follows STATus QUEue ENABle Programming example read error queue NOTE The following example can be run from the...

Страница 335: ...11 24 Status Structure Model 2700 Multimeter Switch System User s Manual...

Страница 336: ...12 CommonCommands...

Страница 337: ...the standard event register after all pending commands have been executed B OPC Operation complete query Places an ASCII 1 into the output queue when all pending selected device operations have been...

Страница 338: ...en used with the immediate initiation command INITiate the OPC bit in the Standard Event Status Register will not set until the Model 2700 goes back into the idle state The INIT command operation is n...

Страница 339: ...ion When this common command is sent an ASCII 1 will be placed in the Output Queue after the last pending operation is completed When the Model 2700 is then addressed to talk the 1 in the Output Queue...

Страница 340: ...700 SAMP COUN 5 to perform five measurements INIT Starts measurement process OPC Sends OPC command After all five measurements are performed and the instrument returns to the idle state an ASCII 1 wil...

Страница 341: ...configuration in memory for later recall Any control affected by RST can be saved by the SAV command The RCL command is used to restore the instrument to the saved setup configuration Four setup conf...

Страница 342: ...urce The control source is programmed from the TRIGger subsystem NOTE Details on triggering are provided in Section 8 Programming example The following command sequence configures Model 2700 to be con...

Страница 343: ...iate are not considered complete until the Model 2700 returns to idle By sending the WAI command after the INITiate command all subsequent commands will not execute until the Model 2700 goes back into...

Страница 344: ...13 SCPISignalOriented MeasurementCommands...

Страница 345: ...quire readings Table 13 1 Signal oriented measurement command summary Command Description CONFigure function rang res clist FETCh READ MEASure function rang res clist Places the Model 2700 in a one sh...

Страница 346: ...error 102 syntax error If only one parameter is used and it is not a clist it is interpreted as the range parameter rang If two parameters are used and the second one is not a clist the first paramete...

Страница 347: ...6Hdigits The resolution of the res parameter value and the selected range sets the number of display digits As shown above with the 100V range selected and res 0 1 a 100V reading will be displayed as...

Страница 348: ...se the READ command to trigger a measurement and acquire a reading see READ When this command is sent without the clist parameter the Model 2700 will be configured as follows The function specified by...

Страница 349: ...buffer In order to return multiple reading strings continuous initiation must be disabled INIT CONT OFF so that the sample count SAMPle COUNt which specifies the number of measurements to be performe...

Страница 350: ...continuous initiation is enabled the READ command will generate error 213 init ignored It can be disabled by sending INITiate CONTinuous OFF The RST command can also be used to disable continuous ini...

Страница 351: ...1 i e 1 000000 V 6Hdigits The resolution of the res parameter value and the selected range sets the number of display digits As shown above with the 100V range selected and res 0 1 a 100V reading will...

Страница 352: ...s sent the following commands execute in the order that they are presented ABORt CONFigure function READ When ABORt is executed the instrument goes into the idle state if continuous initiation is disa...

Страница 353: ...13 10 SCPI Signal Oriented Commands Model 2700 Multimeter Switch System User s Manual...

Страница 354: ...ORMatandMiscellaneous SYSTemCommands FORMat commands Covers the SCPI commands to configure the format that readings are sent over the bus Miscellaneous SYSTem commands Covers miscellaneous SYSTem comm...

Страница 355: ...ACe DATA CALC1 DATA or CALC2 DATA over the GPIB can be returned in either the ASCii or binary format All other queries are returned in ASCii regardless of the selected format Over the RS 232 interface...

Страница 356: ...item list page 14 6 for information on the data elements Figure 14 1 also shows the byte order of the data string Data elements not specified by the ELEMents command are simply not included in the st...

Страница 357: ...will select the binary IEEE 754 single precision data format Double precision data format 64 data bits For the double precision format each data element e g reading is sent as a 8 byte binary data blo...

Страница 358: ...bits s 7 0 7 0 7 0 7 0 e f Byte 1 Byte 2 Byte 7 Byte 8 Bytes 3 4 5 and 6 not shown s sign bit 0 positive 1 negative e exponent bits 11 f fraction bits 52 Normal byte order shown For swapped byte order...

Страница 359: ...only be returned for the ASCII data format For the binary formats timestamp will not be sent with the real time clock selected The relative timestamp operates as a timer that starts at zero seconds w...

Страница 360: ...igh Limit 2 and High Limit 1 have failed FORMat BORDer name Parameters NORMal Normal byte order for IEEE 754 binary format SWAPped Reverse byte order for IEEE 754 binary format For normal byte order t...

Страница 361: ...cases GPIB operation OPC or OPC should be used with SYST PRES which is slow responding command Details on OPC and OPC are provided in Section 12 SYSTem VERSion Read the version of the SCPI standard be...

Страница 362: ...can disable the beeper for limits and continuity tests However when limits or CONT is again selected the beeper will automatically enable Parameters b 0 Disable beeper 1 Enable beeper Figure 14 3 Key...

Страница 363: ...14 10 FORMat and Misc SYSTem Commands Model 2700 Multimeter Switch System User s Manual...

Страница 364: ...15 SCPIReferenceTables...

Страница 365: ...ptional character sets These optional characters do not have to be included in the program message Do not use brackets in the program message Angle brackets are used to indicate parameter type Do not...

Страница 366: ...tor NRf clist Set b factor for mx b 4294967295 to 4294967295 2 0 MBFactor clist Query b factor 2 MA0Factor clist Query b factor 2 MUNits char Specify units for mx b reading 3 X MUNits Query mx b units...

Страница 367: ...uery output pulse time LSENse name Set logic sense of all limit lines AHIGh or ALOW AHIGh LSENse Query logic sense of limit lines LIMit1 Path to control LIMIT 1 test UPPer Path to configure upper limi...

Страница 368: ...limit STATe b clist Enable or disable limit test OFF STATe clist Query state of limit test FAIL Query test result 1 failing CLEAR Path to clear events IMMediate Clear high and low events AUTO b Enabl...

Страница 369: ...display ON ENABle Query state of the display Note RST and SYSTem PRESet have no effect on commands in this subsystem The listed defaults are power on defaults Table 15 3 FORMat command summary Comman...

Страница 370: ...nnels to scan 2 to 55000 Note 1 POINts For a monitor scan query number of channels to scan MONitor Query the channel to be monitored CLOSe clist Close the one specified channel all others will open Se...

Страница 371: ...SOurce Query trigger source for scan NVOLatile b Enable or disable nonvolatile memory for scanning autoscan Note 2 NVOLatile Query nonvolatile memory setting LSELect name Enable INTernal or disable NO...

Страница 372: ...f Set Hold window in 0 01 to 20 1 WINDow Query Hold window COUNt NRf Set Hold count 2 to 100 5 COUNt Query Hold count STATe NRf Enable or disable Hold OFF STATe Query state of Hold CAVerage b clist Ch...

Страница 373: ...resolution 4 to 7 7 Sec 4 DIGits clist Query resolution REFerence n clist Specify reference 1010 to 1010 0 Sec 5 STATe b clist Enable or disable reference OFF STATe clist Query state of reference ACQ...

Страница 374: ...ec 4 DIGits clist Query resolution REFerence n clist Specify reference 757 5 to 757 5 0 Sec 5 STATe b clist Enable or disable reference OFF STATe clist Query state of reference ACQuire clist Use input...

Страница 375: ...auto range DIGits n clist Specify measurement resolution 4 to 7 7 Sec 4 DIGits clist Query resolution REFerence n clist Specify reference 3 1 to 3 1 0 Sec 5 STATe b clist Enable or disable reference...

Страница 376: ...ec 4 DIGits clist Query resolution REFerence n clist Specify reference 3 1 to 3 1 0 Sec 5 STATe b clist Enable or disable reference OFF STATe clist Query state of reference ACQuire clist Use input sig...

Страница 377: ...of auto range DIGits n clist Specify measurement resolution 4 to 7 7 Sec 4 DIGits clist Query resolution REFerence n clist Specify reference 0 to 120e6 0 Sec 5 STATe b clist Enable or disable referen...

Страница 378: ...tion 4 to 7 7 Sec 4 DIGits clist Query resolution REFerence n clist Specify reference 0 to 120e6 0 Sec 5 STATe b clist Enable or disable reference OFF STATe clist Query state of reference ACQuire clis...

Страница 379: ...STATe b clist Enable or disable reference OFF STATe clist Query state of reference ACQuire clist Use input signal as reference REFerence clist Query reference value AVERage Path to configure and contr...

Страница 380: ...23 SIMulated clist Query simulated reference temperature THERmistor Path to configure thermistor Sec 3 TYPE NRf clist Set thermistor type in ohms 1950 to 10050 5000 TYPE clist Query thermistor type FR...

Страница 381: ...e range Sec 3 VOLTage RANGe n clist Select threshold range 0 to 1010 10 RANGe clist Query threshold range PERiod Path to configure period Sec 3 APERture n clist Sets gate time for period measurements...

Страница 382: ...e junction and set the simulated reference temperature TEMPerature RJUNction RSELect name clist Select reference junction SIMulated INTernal or EXTernal TEMPerature RJUNction RSELect clist Query refer...

Страница 383: ...enable register CONDition Read the condition register PRESet Return status registers to default states QUEue Path to access error queue NEXT Read the most recent error message Note 4 ENABle list Spec...

Страница 384: ...ON STATe Query autozero LSYNc Path to control line synchronization Sec 3 STATe b Enable or disable line sync OFF STATe Query state of line sync LFRequency Query power line frequency Sec 1 FRESistance...

Страница 385: ...ed channel 0 no isolated channels AOUTput Path to query analog output channels STARt Request highest numbered analog output channel 0 analog output not supported END Request lowest numbered analog out...

Страница 386: ...Lative Path to reset relative timestamp RESet Reset relative timestamp to 0 RNUMber Path to reset reading number Sec 14 RESet Reset reading number Next reading will be 1 ERRor Query read Error Queue N...

Страница 387: ...be less than TRACe POINts value 50 NOTify Query trace notify value NEXT Query buffer location for next stored reading TSTamp Path to set timestamp format FORMat name Select timestamp format ABSolute...

Страница 388: ...Query measure count DELay n Set delay 0 to 999999 999 sec 0 AUTO b Enable or disable auto delay OFF AUTO Query state of delay DELay Query delay SOURce name Select control source IMMediate TIMer MANua...

Страница 389: ...perature units VOLTage Path to configure voltage units Sec 5 DC name clist Select DCV measurement units V or DB V DB Path to set DB reference voltage REFerence n Specify reference in volts 1e 7 to 100...

Страница 390: ...A Specifications Model 2700 Data Acquisition Control System Model 7700 20 Channel Differential Multiplexer w Automatic CJC...

Страница 391: ...A 2 Specifications Model 2700 Multimeter Switch System User s Manual...

Страница 392: ...Model 2700 Multimeter Switch System User s Manual Specifications A 3...

Страница 393: ...A 4 Specifications Model 2700 Multimeter Switch System User s Manual...

Страница 394: ...Model 2700 Multimeter Switch System User s Manual Specifications A 5...

Страница 395: ...A 6 Specifications Model 2700 Multimeter Switch System User s Manual...

Страница 396: ...5V 200 V or from 4 9998V to 5 0002V DC current and resistance calculations are performed in exactly the same manner using the pertinent specifications ranges and input signal values Calculating AC ch...

Страница 397: ...eading range is 13dBm 0 00032dBm dBm and dB for other voltage inputs can be calculated in exactly the same manner using pertinent specifications ranges and reference impedances Calculating dB characte...

Страница 398: ...ional derating factor of 0 02ppm V must be added to DCV specifications for voltages over 500V Before calculating accuracy study the associated specifications very carefully to see if any derating fact...

Страница 399: ...ad factory setups restored DC voltage DC current and resistance Select 3Hdigits 0 01 PLC filter OFF fixed range AC voltage and AC current Select 3Hdigits 0 01 PLC filter OFF fixed range Temperature Se...

Страница 400: ...B Model7700ConnectionGuide...

Страница 401: ...n a few seconds after either a power cycle or a RST command is issued Connections to DMM functions for system channel operation are provided through the card backplane connector Current provided throu...

Страница 402: ...nnel 23 2 Pole Open 4 Pole Closed See Note 3A 3A To Model 2700 Backplane Channel 25 See Note Backplane Isolation Channel 24 See Note Backplane Isolation Channels 23 and 25 in this schematic refer to t...

Страница 403: ...terminals and the switching module terminals are connected at the same time the test lead insulation must be rated to the highest voltage that is connected For example if 1000V is connected to the fr...

Страница 404: ...nnel designations for the screw terminals are contained in Figure B 3 Figure B 2 Screw terminal access SENSE OHMS 4 WIRE INPUT V 2 WIRE U N L O C K LOCK CH7 H L CH8 H L CH9 H L CH10 H L H L CH21 H L C...

Страница 405: ...is applied to the front terminals of the DMM the plug in module wiring must be rated for 1000V 1 Make sure all power is discharged from the Model 7700 module 2 Access the screw terminals Figure B 2 C...

Страница 406: ...hown 5 Fill in a copy of the connection log Table B 1 and affix it to the module cover 6 Close and lock cover Figure B 4 Wire dressing Supplementary Insulation CH7 H L CH8 H L CH9 H L CH10 H L H L CH2...

Страница 407: ...couple connections Figure B 5 2 Wire and thermistor connections Figure B 6 4 Wire and RTD connections Figure B 7 Current connections AC or DC Figure B 8 Voltage connections AC or DC Figure B 9 Figure...

Страница 408: ...tion Guide B 9 Figure B 7 4 Wire and RTD connections Figure B 8 Current connections AC or DC Channel 1 HI LO Channel 10 HI LO Channels 2 9 Channel 11 HI LO Channel 20 HI LO Channels 12 19 Resistor or...

Страница 409: ...Manual Figure B 9 Voltage connections DC or AC Connection log Make a copy of Table B 1 and affix it to the cover of the Model 7700 Use this to record connection information and channel descriptions as...

Страница 410: ...le B 1 Connection log Model 7700 Channel Color Description AMPS COM H L INPUT H L SENSE H L CH1 H L CH2 H L CH3 H L CH4 H L CH5 H L CH6 H L CH7 H L CH8 H L CH9 H L CH10 H L CH11 H L CH12 H L CH13 H L...

Страница 411: ...B 12 Model 7700 Connection Guide Model 2700 Multimeter Switch System User s Manual...

Страница 412: ...C StatusandErrorMessages...

Страница 413: ...error Program currently running Illegal program name Cannot create program Expression error Hardware missing Data corrupt or stale Out of memory Illegal parameter value Too much data Parameter data o...

Страница 414: ...d Too many digits Exponent too large Invalid character in number Numeric data error Header suffix out of range Undefined header Program mnemonic too long Header separator error Command header error Mi...

Страница 415: ...Program running Waiting in trigger layer Re entering the idle layer Filter settled Reading overflow Low limit 1 event High limit 1 event Low limit 2 event High limit 2 event Reading available Buffer...

Страница 416: ...4 w zero error 10M 4 w sense lo zero error 1k 4 w full scale error 10k 4 w full scale error 100k 4 w full scale error 1M 4 w full scale error 10M 4 w full scale error 10m adc zero error 100m adc zero...

Страница 417: ...rror 1K Ohm loff Ocomp FS error 10K Ohm loff Ocomp FS error Temperature Cold Cal error Analog output zero error Analog output pos gain error Analog output neg gain error 1k 4 w dckt Ioff zero error 1k...

Страница 418: ...ates lost Battery backed RAM error Cannot resume scan Card calibration data lost Card calibration dates lost Saved setup scancard mismatch Card relay counts lost EE EE EE EE EE EE EE EE EE EE EE EE EE...

Страница 419: ...C 8 Status and Error Messages Model 2700 Multimeter Switch System User s Manual...

Страница 420: ...D SignalProcessing SequenceandDataFlow...

Страница 421: ...signal conditioning transforms the input signal into a DC voltage that is applied to the A D converter The A D Conversion Process measures the DC signal voltage and internal voltages that correspond...

Страница 422: ...re is not enabled the reading simply falls through to the next enabled feature or to the display Figure D 2 Signal processing using instrument features Input Signal Rel Math mX b Percent or Reciprocal...

Страница 423: ...e specified number of readings to be averaged In general for the moving filter each measurement process adds a reading to the stack oldest reading discarded and then averages the stack to yield a filt...

Страница 424: ...w chart is not modified and is the reading that is displayed on the Model 2700 With Limits enabled the reading is tested against two sets of high and low limits Along with the displayed reading annunc...

Страница 425: ...value for the calculation The paired channel then closes and that reading is used as the Chan B value for the calculation Ratio or Ch Avg is then calculated as shown in Figure D 3 As shown the result...

Страница 426: ...easurement cycle Data flow for this triggering configuration is summarized by the block diagram shown in Figure D 4 Refer to this block diagram for the following discussion Figure D 4 Data flow for re...

Страница 427: ...nuous OFF command disables continuous initiation and TRIGger COUNt 1 configures the instrument to perform one measurement cycle The INIT command can then be used to initiate the measurement cycle When...

Страница 428: ...numbers in the data arrays Reading numbers that do not change will indicate that the same data array is being returned NOTE The FORMat ELEMents command see Section 14 is used to include the reading nu...

Страница 429: ...math calculation Note that FETCh does not affect data in the sample buffer Therefore subsequent executions of FETCh acquire the same data NOTE When an instrument setting that is relevant to the readin...

Страница 430: ...r These commands do not affect data in the sample buffer Therefore subsequent executions of these commands return the same data With no math function enabled these commands return the last data array...

Страница 431: ...c calculation will be returned when a read operation CALC2 IMM or CALC2 DATA is performed However if there was no calculation previously performed the number 9 910000E 37 will instead be returned Cont...

Страница 432: ...rm Note that if the trigger count is 1 the data for each subsequent scan will overwrite the data stored in the sample buffer and data store Once the scan is properly configured INIT or READ will start...

Страница 433: ...D 14 Signal Processing Sequence and Data Flow Model 2700 Multimeter Switch System User s Manual...

Страница 434: ...E MeasurementConsiderations...

Страница 435: ...s see the Low Level Measurements handbook which is available from Keithley Thermoelectric potentials Thermoelectric potentials thermal EMFs are small electric potentials generated by differences in te...

Страница 436: ...perature of B junction C or K T2 Temperature of A junction C or K In the unlikely event that the two junction temperatures are identical no thermal EMFs will be generated More often the two junction t...

Страница 437: ...ied to ensure the connection is gas tight to prevent future oxidation In some cases connecting the two thermal junctions together with good thermal contact to a common heat sink may be required Unfort...

Страница 438: ...urce resistance of 10k the noise over a 0 5Hz bandwidth at room temperature will be Minimizing source resistance noise From the above examples it is obvious that noise can be reduced in several ways 1...

Страница 439: ...erence over a wide range of frequencies across the spectrum Such RFI can be particularly troublesome at low signal levels but it can also affect measurements at high levels if the fields are of suffic...

Страница 440: ...measurement Figure E 2 Power line ground loops Figure E 3 shows how to connect several instruments together to eliminate this type of ground loop problem Here only one instrument is connected to power...

Страница 441: ...el measurement situation Otherwise interference from such noise sources as line frequency and RF fields can seriously corrupt measurements rendering experimental data virtually useless In order to min...

Страница 442: ...e RS while the input resistance of the Model 2700 is RI and the voltage measured by the nanovoltmeter is VM Figure E 5 Meter loading The voltage actually measured by the meter is attenuated by the vol...

Страница 443: ...E 10 Measurement Considerations Model 2700 Multimeter Switch System User s Manual...

Страница 444: ...ients to calculate thermocouple temperature Thermistor equation Documents the Steinhart Hart equation which is used to calculate thermistor temperature RTD equation Documents the Callendar Van Dusen e...

Страница 445: ...icients for each thermocouple type are listed in Table F 1 through Table F 8 Table F 1 Type B inverse function polynomial 250 C to 700 C 291 V to 2 431 V 700 C to 1 820 C 2 431 V to 13 820 V c0 c1 c2...

Страница 446: ...here t90 is the calculated temperature in C E is the measured voltage in microvolts Table F 3 Type J inverse function polynomial 210 C to 0 C 8 095 V to 0 V 0 C to 760 C 0 V to 42 919 V 760 C to 1 200...

Страница 447: ...ror 0 04 C to 0 02 C 0 04 C to 0 05 C 0 06 C to 0 05 C t90 c0 c1E c2E2 c3E3 ciEi where t90 is the calculated temperature in C E is the measured voltage in microvolts Table F 5 Type N inverse function...

Страница 448: ...to 0 0005 C 0 002 C to 0 001 C t90 c0 c1E c2E2 c3E3 ciEi where t90 is the calculated temperature in C E is the measured voltage in microvolts Table F 7 Type S inverse function polynomial 50 C to 250...

Страница 449: ...o 0 V 0 C to 400 C 0 V to 20 872 V c0 0 0 0 0 c1 2 594 919 2 10 2 2 592 800 10 2 c2 2 131 696 7 10 7 7 602 961 10 7 c3 7 901 869 2 10 10 4 637 791 10 11 c4 4 252 777 7 10 13 2 165 394 10 15 c5 1 330 4...

Страница 450: ...e affected 1 Choose the thermistor type to be used 2252 5k or 10k 2 Compare the A B and C constants from the thermistor manufacturer with those used by the Model 2700 see Table F 9 3 Select a thermist...

Страница 451: ...ion for 200 to 0 C temperature range RRTD R0 1 AT BT2 CT3 T 100 where RRTD is the calculated resistance of the RTD R0 is the known RTD resistance at 0 C T is the temperature in C A alpha 1 delta 100 B...

Страница 452: ...a and delta values A and B are calculated as follows A 0 00385 1 1 4999 100 0 00385 1 014999 0 003907746 B 1 0 00385 1 4999 1e 4 1 0 005774615 1e 4 5 774615e 7 The resistance of the RTD at 100 C R100...

Страница 453: ...lta 1 49710 Using the above alpha and delta values A and B are calculated as follows A 0 003920 1 1 49710 100 0 003920 1 014971 0 003978686 B 1 0 003920 1 49710 1e 4 1 0 005868632 1e 4 5 868632e 7 C 1...

Страница 454: ...G IEEE 488BusOverview...

Страница 455: ...ibility of the information transfer The basic handshake sequence between an active controller talker and a listener is as follows 1 The listener indicates that it is ready to listen 2 The talker place...

Страница 456: ...Device 1 able to talk listen and control computer Device 2 able to talk and listen 2700 Device 3 only able to listen printer Device 4 only able to talk DAV NRFD NDAC IFC ATN SRQ REN EOI Data Bus Data...

Страница 457: ...36 16 20 In a similar manner the talk address is obtained by ORing the primary address with 40 With the present example the talk address derived from a primary address of 16 would be 56 56 16 40 The I...

Страница 458: ...aining two lines are controlled by accepting devices the listener or listeners receiving the information The three handshake lines are DAV DATA VALID The source controls the state of the DAV line to i...

Страница 459: ...ng paragraphs Figure G 2 IEEE 488 handshake sequence Bus commands The instrument may be given a number of special bus commands through the IEEE 488 interface The following paragraphs briefly describe...

Страница 460: ...L Go To Local UNL Unlisten UNT Untalk X X X Low X Low Low Low Low Low Low Low Low High High Set up devices for remote operation Marks end of transmission Clears interface Defines data bus contents Con...

Страница 461: ...ly IFC Interface Clear IFC is used to clear the interface and return all devices to the talker and listener idle states ATN Attention The controller sends ATN while transmitting addresses or multiline...

Страница 462: ...configuration for example take a reading Although GET is an addressed command many devices respond to GET without addressing Address commands Addressed commands include two primary command groups and...

Страница 463: ...urer and are based on the instrument model defined by the Standard Commands for Programmable Instruments SCPI Consortium s SCPI standard Generally these commands are sent as one or more ASCII characte...

Страница 464: ...1 A DLE DC1 DC2 DC3 DC4 NAK SYN ETB CAN EM SUB ESC FS GS RS US LLO DCL PPU SPE SPD 1 B 2 A SP _ 2 B 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 3 A 0 1 2 3 4 5 6 7 8 9 3 B 16 17 18 19 20 21 22 23 24 25 26 2...

Страница 465: ...listeners are present Note that ATN is true for both the listen command and the SDC command byte itself Table G 4 gives a typical common command sequence In this instance ATN is true while the instrum...

Страница 466: ...FOR DATA DAV DATA VALID UNIVERSAL COMMAND GROUP ATN ATTENTION DCL DEVICE CLEAR IFC INTERFACE CLEAR REN REMOTE ENABLE SPD SERIAL POLL DISABLE SPE SERIAL POLL ENABLE ADDRESS COMMAND GROUP LISTEN TALK L...

Страница 467: ...pabilities T5 exist only after the instrument has been addressed to talk L Listener Function The ability for the instrument to receive device dependent data over the bus from other devices is provided...

Страница 468: ...ared initialized DT Device Trigger Function DTI defines the ability of the Model 2700 to have readings triggered C Controller Function The instrument does not have controller capabilities C0 TE Extend...

Страница 469: ...G 16 IEEE 488 Bus Overview Model 2700 Multimeter Switch System User s Manual...

Страница 470: ...H KE2700InstrumentDriver Examples...

Страница 471: ...me of the examples demonstrate the simple command sequence examples that are used throughout this manual These examples include a reference to appropriate manual section in the References column of th...

Страница 472: ...V 15 on 100mV range 15 on 10V range 9 channels ACV 1V range 1 channel 4 wire RTD temperature Measurement speed rate 1 plc Filter Disabled no filtering Buffer Store 160 reading strings Buffer elements...

Страница 473: ...filtering Buffer Store 40 DCV reading strings 20 4 reading strings Buffer elements include reading only Limits DCV scan Limit 1 all channels 20mV Master Latch enabled Triggering Bus control source Da...

Страница 474: ...l reference junction Keep in mind that the buffer and data retrieval will have to be modified to accommodate the number of scanned channels Modules that have cold junction include 7700 and 7706 module...

Страница 475: ...put channels of the 7706 module AOCalibration See 7706 packing list Demonstrates how to remotely calibrate the analog output channels of the 7706 module BufStats Page 6 15 Prog Ex Demonstrates calcula...

Страница 476: ...dth settings Ratio1 Page 5 20 Ex 1 Demonstrates ratio calculation Ratio2 Page 5 20 Ex 2 Demonstrates ratio and channel average functions ReadError Queue Page 11 23 Prog Ex Demonstrates reading the err...

Страница 477: ...uffer elements include reading only Triggering Bus control source Simple3 None Use Case 3 Two scans using 7708 module 40 channel DCV 1V range scan 20 channel 4 scan Models 2700 and 2701 100 range Mode...

Страница 478: ...input impedance Filter Disabled no filtering Buffer Store 40 DCV reading strings 20 4 reading strings Buffer elements include reading only Limits DCV scan Limit 1 all channels 20mV Master Latch enabl...

Страница 479: ...use the Internal reference junction Keep in mind that the buffer will have to be modified to accommodate the number of scanned channels Modules that have cold junction include 7700 and 7706 modules 2...

Страница 480: ...gs Buffer elements include reading only Triggering Bus control source trigger delay 0 125 seconds SOPC Page 12 4 Demonstrates operation complete query OPC SrSetup Page 12 6 Demonstrates saving and rec...

Страница 481: ...ng and reading multiple data points from switching module channels Read multi point from front panel None Demonstrates configuring and reading multiple data points from the front panel input Read sing...

Страница 482: ...ing Timer scan 40 channels every one minute Data retrieval SRQ when buffer G H I and full Advance3 None Use Case 3 Two scans using 7708 module 40 channel DCV 1V range scan 20 channel 4 scan Models 270...

Страница 483: ...abled no filtering Buffer Store 40 DCV reading strings 20 4 reading strings Buffer elements include reading only Limits DCV scan Limit 1 all channels 20mV Master Latch enabled Triggering Bus control s...

Страница 484: ...Internal reference junction Keep in mind that the buffer and data retrieval will have to be modified to accommodate the number of scanned channels Modules that have cold junction include 7700 and 770...

Страница 485: ...d limit code Triggering Bus control source trigger delay 0 125 seconds Data retrieval SRQ when buffer G H I and full Simple1 None Use Case 1 30 channel scan using 7708 module 30 channels DCV 10V range...

Страница 486: ...s DCV scan Limit 1 all channels 20mV Master Latch enabled Triggering Bus control source Simple4 None Use Case 4 Two scans using 7708 module 40 channel DCV scan 1V range Configuration saved in User Set...

Страница 487: ...ring Immediate control source Simple6 None Use Case 6 Scan 160 channels using 7703 module see NOTE Type K thermocouple TC temperature measurements Reference junction Simulated Measurement speed rate 0...

Страница 488: ...Filter Disabled no filtering Buffer Store 400 reading strings Buffer elements include reading only Triggering Bus control source Simple8 None Use Case 8 7706 module in slot 1 and 7702 module in slot...

Страница 489: ...H 20 KE2700 Instrument Driver Examples Model 2700 Multimeter Switch System User s Manual...

Страница 490: ...asurements 3 7 Basic operation 3 1 Overview 3 2 Baud rate 10 18 Beeper control 8 7 Buffer 6 1 7 27 Auto clear 6 2 Clear 6 12 Commands 6 9 CALCulate2 DATA 6 15 CALCulate2 FORMat 6 15 CALCulate2 IMMedia...

Страница 491: ...19 Rel 5 4 Scanning 7 27 SCPI see FORMat commands SCPI refer ence tables and SYSTem commands Setups 1 25 Status byte and service request 11 9 System channel control 2 12 Triggering 8 18 Unaddress G 9...

Страница 492: ...mote programming 4 6 Scanning 4 6 Setting 4 7 Display 1 18 Annunciators 1 12 Commands 1 18 DISPlay ENABle 1 19 DISPlay TEXT DATA 1 19 DISPlay TEXT STATe 1 19 Programming example 1 19 Remote programmin...

Страница 493: ...to local 10 9 IFC interface clear 10 8 LLO local lockout 10 9 REN remote enable 10 8 SDC selective device clear 10 9 SPE SPD serial polling 10 9 General information 1 2 Getting started 1 1 GPIB Confi...

Страница 494: ...5 12 Setting mX b units 5 14 Math commands Reading math result 5 14 Measurement event status 11 16 Measurement queries 3 56 FETCh 3 56 MEASure function 3 58 READ 3 57 SENSe 1 DATA FRESh 3 58 SENSe 1 D...

Страница 495: ...Power switch 1 11 Power up 1 15 Sequence 1 17 Primary address Setting 10 4 Program message terminator PMT 10 16 Program messages 10 15 Programming syntax 10 11 Pseudocards 1 9 2 5 10 2 Q Questionable...

Страница 496: ...ult and user setups 1 25 Digits 4 6 Display 1 18 Filter 4 20 Information 1 26 Math 5 13 Multiple channel control commands 2 20 Range 4 4 Rate and bandwidth 4 10 Ratio and channel average 5 19 Rel 5 4...

Страница 497: ...t commands 13 1 CONFigure function rang res clist 13 4 FETCh 13 6 READ 13 7 Serial polling and SRQ 11 8 Settings Default 1 20 1 22 Setups 1 20 Commands 1 25 Remote programming 1 25 Restoring 1 21 Savi...

Страница 498: ...time clock timestamp 6 4 Relative 6 4 Selecting 6 5 Setting time and date 6 5 TRIG LINK 1 14 TRIG LINK pinout 8 8 Trigger link Connections 8 11 Input 9 5 Input pulse specifications EXT TRIG 8 8 Outpu...

Страница 499: ......

Страница 500: ...ll other trademarks and trade names are the property of their respective companies A G R E A T E R M E A S U R E O F C O N F I D E N C E Keithley Instruments Inc Corporate Headquarters 28775 Aurora Ro...

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