Keithley 2750, User Manual

Page 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 2750 900 01 Rev F August 2011 Model 2750 Multimeter Switch System...

Page 2: ...2750 Multimeter Switch System User s Manual 2011 Keithley Instruments Inc All rights reserved Cleveland Ohio U S A Document Number 2750 900 01 Rev F 2750 900 01 book Page 1 Wednesday August 3 2011 7...

Page 3: ...2750 900 01 book Page 2 Wednesday August 3 2011 7 56 AM...

Page 4: ...uld be performed only by service personnel Service personnel are trained to work on live circuits perform safe installations and repair products Only properly trained service personnel may perform ins...

Page 5: ...surface capable of withstanding the voltage being measured The instrument and accessories must be used in accordance with its specifications and operating instructions or the safety of the equipment m...

Page 6: ...ther 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 be purchased only through Kei...

Page 7: ...2750 900 01 book Page 4 Wednesday August 3 2011 7 56 AM...

Page 8: ...16 Display 1 17 Status and error messages 1 17 Remote programming display 1 17 Defaults and user setups 1 19 Saving and restoring setups 1 20 Remote programming default and user setups 1 24 Remote pro...

Page 9: ...M Operation DMM measurement 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...

Page 10: ...ing examples 3 49 Measurement queries 3 50 FETCh 3 50 READ 3 51 MEASure function 3 51 SENSe 1 DATA FRESh 3 52 SENSe 1 DATA LATest 3 52 Examples 3 53 4 Range Digits Rate Bandwidth and Filter Range 4 2...

Page 11: ...Timestamps 6 3 Storing readings 6 5 Recalling readings 6 6 Buffer statistics 6 7 Remote programming buffer 6 8 Buffer commands 6 8 Programming example 6 15 7 Scanning Scanning fundamentals 7 2 Channel...

Page 12: ...7 Voltmeter complete 8 7 External triggering example 8 8 External triggering with BNC connections 8 11 Remote programming triggering 8 12 Trigger model remote operation 8 12 Trigger model operation 8...

Page 13: ...ice clear 10 9 GET group execute trigger 10 9 SPE SPD serial polling 10 9 Front panel GPIB operation 10 10 Error and status messages 10 10 GPIB status indicators 10 10 LOCAL key 10 11 Programming synt...

Page 14: ...ple 11 9 Status register sets 11 11 Register bit descriptions 11 11 Condition registers 11 18 Event registers 11 18 Event enable registers 11 19 Queues 11 20 Output queue 11 20 Error queue 11 20 12 Co...

Page 15: ...instrument features D 3 Signal processing using Ratio or Ch Avg D 6 Data flow remote operation D 7 SENSe and sample buffer D 8 SENS 1 DATA LATest D 9 SENS 1 DATA FRESh D 9 FETCh D 9 READ D 9 MEASure D...

Page 16: ...ction G 2 Bus description G 2 Bus lines G 4 Data lines G 4 Bus management lines G 5 Handshake lines G 5 Bus commands G 6 Uniline commands G 8 Universal multiline commands G 8 Addressed multiline comma...

Page 17: ...2750 900 01 book Page 10 Wednesday August 3 2011 7 56 AM...

Page 18: ...dules QS1 Front and rear panel familiarization Summarizes the controls and connectors of the instrument Rack mounting Covers the options available for rack mounting the Model 2750 in a standard 19 inc...

Page 19: ...n 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 on the termi nal s Use standar...

Page 20: ...manual package The manual packages include a manual and any pertinent addenda Options and accessories Plug in switching modules NOTE Table 1 1 provides a side by side comparison of the following Keit...

Page 21: ...lief connector shells These connectors mate to the female connectors of the Models 7703 and 7705 switching modules Model 7789 50 25 pin solder cup connector kit Contains one male DB 50 and one male DB...

Page 22: ...d or scanned is measured by the Model 2750 For scanning each channel can have its own unique setup i e function range digits etc More information on the measurement capabilities of the Model 2750 is p...

Page 23: ...d in the packing list that was shipped with each switching module Table 1 1 Model 77XX series switching modules Model 7700 Model 7701 Model 7702 Model 7703 Model 7705 2 pole operation 4 pole operation...

Page 24: ...c tromechanical 1 male DB 50 1 female DB 25 Multiplexer 32 digital inputs outputs 40 channels 20 channel pairs N A 300V Max No 2 4 wire Yes Latching elec tromechanical Oversizedscrew terminals Multipl...

Page 25: ...e slot indicators on the right side of the display indicate which slots have a switching module or pseudocard installed NOTE If a Model 7700 7701 7702 7703 7705 7708 or 7709 switching module is remove...

Page 26: ...wire resistance measurement function 4 Selects 4 wire resistance measurement function FREQ Selects frequency measurement function TEMP Selects temperature measurement function Shifted MATH Configures...

Page 27: ...Unshifted OPEN Opens closed channel CLOSE Closes specified channel STEP Steps through channels sends a trigger after each channel SCAN Scans through channels sends a trigger after last channel DIGITS...

Page 28: ...nt panel input terminals disconnected REL Relative enabled for selected function REM Instrument in GPIB remote mode SCAN Scanning operation being performed SHIFT Accessing a shifted key SLOW Slow read...

Page 29: ...l modem DB 9 shielded cable 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 li...

Page 30: ...de install two retaining clips on the left front rail Slide each retaining clip over a mounting hole such that the captive nut is positioned on the inside of the rack cabinet In a similar manner insta...

Page 31: ...male end of the supplied power cord to the AC receptacle on the rear panel Connect the other end of the power cord to a grounded AC outlet WARNING The power cord supplied with the Model 2750 contains...

Page 32: ...le by the fuse holder assembly Figure 1 4 Gently push in and up Release pressure on the assembly and its internal spring will push it out of the power module 2 Remove the fuse and replace it with the...

Page 33: ...l five slots the following messages will be displayed 1 7700 2 7700 3 7700 4 7700 5 7700 If a slot is empty the message NONE will be displayed instead If the saved power on setup is not the factory de...

Page 34: ...arily During operation and programming you will encounter a number of front panel messages Typical messages are either of status or error variety as listed in Appendix C Remote programming display Usi...

Page 35: ...as long as the instrument is in remote Taking the instrument out of remote by pressing the LOCAL key or sending GTL can cels the message and disables the text message mode DISPlay ENABle ON OFF Contr...

Page 36: ...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 are used to reset the instrume...

Page 37: ...SAV2 4 Press 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...

Page 38: ...igits Range 1k 1k Rate Fast 0 1 PLC Fast 0 1 PLC Threshold level 10 10 Current AC and DC Bandwidth AC 30 30 Digits AC 5Hdigits 5Hdigits Digits DC 6Hdigits 6Hdigits Filter On Off Window 0 1 0 1 Count 1...

Page 39: ...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 Off Off Resistance 2 and 4 Digits 6Hdi...

Page 40: ...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 Digits 5Hd...

Page 41: ...Count 10 10 Type Moving Repeat Range Auto Auto Rate DC Slow 5 PLC Slow 5 PLC Rel Off Off Note With a Model 7700 7706 or 7708 installed the default sensor junction is Internal Otherwise the Simulated 2...

Page 42: ...ional command words Any command word that is enclosed in brackets is optional and does not have to be included in the program message Query commands Most command words have a query form A query comman...

Page 43: ...ak the setup range rate filter digits etc as required For remote programming the instrument is typically used in a non continuous measure ment mode In this mode the user via remote command programming...

Page 44: ...LT AC RANG 10 6 Store 15 readings in buffer3 Press STORE set for 000015 RDGS press ENTER SAMP COUN 15 READ 7 Recall buffer readings4 Press RECALL use edit keys to display readings Press EXIT to exit r...

Page 45: ...function the resistance DUT would be connected to DMM Input as shown Figure 1 5 For a 4 wire function i e 4 a channel pair is connected to the DMM when a system channel is closed The system channel i...

Page 46: ...0 The slot number for the module is also displayed For example 103 indicates that system input channel 3 for a module in slot 1 is closed The paired channel for a 4 wire function is not displayed Only...

Page 47: ...the following command would be sent ROUTe CLOSe 103 2 Only the closed system channel is returned by ROUTe CLOSe The paired channel for a 4 wire function is not returned For example assume channel 2 i...

Page 48: ...ume there are 10 channels in the scan list i e 101 through 110 If you set the reading count to 10 or less one scan of the 10 channels will be per formed If you set the reading count to any value from...

Page 49: ...minimum channel XXX and press ENTER SHIFT SCAN STEP CONFIG Press SHIFT Press CONFIG STEP MAX CHAN YYY Specify maximum channel YYY and press ENTER TIMER NO YES Display NO or YES and press ENTER YES NO...

Page 50: ...the read ings 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 programming clear the buffer TRAC CLE...

Page 51: ...ands i e FETCh READ Section 15 See Table 15 9 Trigger command summary Appendix D Shows how trigger and read commands control data flow within the instrument NOTE Each exercise indicates the commands u...

Page 52: ...ply return the last reading If you again send one of these commands before triggering a new reading the old reading will be returned Return Basic Reading3 4 INIT Trigger Reading READ 2 If there is no...

Page 53: ...red 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 TRAC CLE Clear Buffer1 Trigge...

Page 54: ...l 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 trigger measurements They sim...

Page 55: ...1 38 Getting Started Model 2750 Multimeter Switch System User s Manual 2750 900 01 book Page 38 Wednesday August 3 2011 7 56 AM...

Page 56: ...tem channel operation Multiple channel operation Provides detailed information for using multiple channel operation Due to safety considerations this operating mode should only be used by experienced...

Page 57: ...put for that module Most switching modules 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 num...

Page 58: ...le 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 personal con tact with high v...

Page 59: ...ected For example if 1000V is con nected to the front panel input the test lead insulation for the switch ing module must also be rated for 1000V Dangerous arcs of an explosive nature in a high energy...

Page 60: ...m PCARd2 name Install pseudocard in slot 2 SYSTem PCARd3 name Install pseudocard in slot 3 SYSTem PCARd4 name Install pseudocard in slot 4 SYSTem PCARd5 name Install pseudocard in slot 5 name C7700 C7...

Page 61: ...channel operation include the following There can only be one system channel This is the channel that is presently dis played and closed on the Model 2750 When a channel is not displayed there is no...

Page 62: ...as the paired channel For a switching module that has 20 measurement channels channel 1 is paired to channel 11 channel 2 is paired to channel 12 channel 3 is paired to channel 13 and so on Figure 2...

Page 63: ...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 All five slots ar...

Page 64: ...XXX 3 Using and key in the three digit channel you want to select 4 Press ENTER The channel closes and the CHAN annunciator turns on An invalid channel cannot be closed and will cause one of the foll...

Page 65: ...will open all measurement channels 101 to 120 121 and 122 the backplane isolation channels 124 and 125 and the 2 pole 4 pole channel 123 Figure 2 2 shows the backplane isolation channels and the 2 pol...

Page 66: ...ll 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 For example assume clist 101 104...

Page 67: ...here are modules that do not support any measurements at all Non amps module With an amps function selected DCI or ACI system channel oper ation cannot be used to close channels on that module Non mea...

Page 68: ...the DCI or ACI function the message INVALID FUNC will be displayed briefly For remote programming error 221 Settings conflict is generated Example SYST PRES Restores system preset defaults ROUT CLOS...

Page 69: ...are used to close channels Front panel system single channel operation cannot be used to close channels on a non measure module For front panel operation system channel operation will cause message N...

Page 70: ...ing modules and external circuitry Multiple channel operation should be restricted to experienced test engineers who recognize the dangers associated with multiple channel closures NOTE Multiple chann...

Page 71: ...ng module that is connected to an external source that is turned on Turn off all power sources before 1 making or breaking connec tions to the module and 2 installing or removing the module into or ou...

Page 72: ...ated with system channel operation also apply to multiple channel operation Figure 2 6 Multiple channel operation specifying a channel to close OPEN key The OPEN key has two options to open channels A...

Page 73: ...Table 2 2 Multiple channel control commands Commands Description Ref ROUTe MULTiple CLOSe clist Specify one or more channels to close a ROUTe MULTiple OPEN clist Open channels specified in list Unlist...

Page 74: ...clist With this command you can open one or more switching module channels When you send this command to open the channels specified in the clist only those listed channels will open Channels not spec...

Page 75: ...ct the already closed system channel it will not re close the paired channel For details see Anomaly 2 example opening the paired channel NOTE The following anomaly examples assume a Model 7700 instal...

Page 76: ...s channel 101 to DMM Input Channel 111 paired channel for 4 wire measurements Channel 124 connects channel 111 to DMM Sense Channel 123 isolates channel 101 from channel 111 The Model 2750 will displa...

Page 77: ...The Model 7700 is configured as two inde pendent multiplexers by closing channel 23 As shown in Figure 2 8 the closed position of channel 23 isolates Multiplexer A channels 1 through 10 from Multiplex...

Page 78: ...emain closed while testing DUT Opening channel 24 isolates the external source from the backplane of the Model 2750 This channel must remain open while testing DUT Closing channel 25 connects an input...

Page 79: ...al multiplexer application connections Ch 1 DUT 1 H1 LO Ch 2 DUT 2 H1 LO Ch 10 DUT 10 H1 LO Ch 11 H1 LO Ch 12 H1 LO Ch 20 H1 LO Ch 23 Closed Ch 25 Ch 24 H1 LO External Source Model 7700 Switching Modu...

Page 80: ...afe practice to open all channels at the start and end of the test Front panel operation Press OPEN Display ALL Press OPEN Remote programming ROUT OPEN ALL 2 Close channels 23 and 25 Front panel opera...

Page 81: ...last DUT is tested repeat step 1 to open all channels Figure 2 10 Testing DUT 1 DMM Model 7700 Switching Module Model 2750 Slot 1 Equivalent Circuit DUT 1 Ch 23 Closed HI LO HI LO HI LO HI LO HI LO DM...

Page 82: ...the following operations Configure digital inputs and outputs and analog outputs for switching modules that have one or more of those capabilities i e Models 7706 and 7707 View the analog input channe...

Page 83: ...channels for the 4 wire measurement Channel 123 is the 4 pole relay setting and channels 124 and 125 connect input and sense to the DMM of the Model 2750 Figure 2 2 NOTE Some switching modules have a...

Page 84: ...he OPT command can be used to determine which switching modules or pseudocards are installed in the Model 2750 For example assume a Model 7700 is installed in slot 1 a Model 7706 is installed in slot...

Page 85: ...0 is returned for an open channel and a 1 is returned for a closed channel For details see Table 2 2 and related reference information SYSTem CARD commands There is a series of SYSTem CARD commands t...

Page 86: ...e summa rized in Table 2 3 Details follow the table NOTE The relay closure count can be reset to zero For details see Model 2750 Service Manual Plug in module relay closure count Table 2 3 Relay closu...

Page 87: ...nly 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 between 10 and 1440 minutes...

Page 88: ...nnels 23 24 and 25 The open close state of these channels are deter mined by the selected function The Model 7700 has six temperature transducers to monitor the cold junction temperature at the screw...

Page 89: ...backplane When a 4 wire function is selected channel 23 closes 4 pole position to isolate channels 1 through 10 from channels 11 through 20 With a system channel 1 through 10 closed its paired channe...

Page 90: ...Channel 23 2 Pole Open 4 Pole Closed See Note 3A 3A To Model 2750 Backplane Channel 25 See Note Backplane Isolation Channel 24 See Note Backplane Isolation Channels 23 and 25 in this schematic refer t...

Page 91: ...2 36 Close Open Switching Module Channels Model 2750 Multimeter Switch System User s Manual 2750 900 01 book Page 36 Wednesday August 3 2011 7 56 AM...

Page 92: ...easurements DCI and ACI Provides detailed information for making basic DC and AC current measurements Resistance measurements Provides detailed information for making resistance measurements Also cove...

Page 93: ...to 2 s TEMP Temperature measurements from 200 C to 1820 C CONT Continuity testing using the 1k range CAUTION When using a switching module do not exceed the maximum signal levels of the module To prev...

Page 94: ...tor 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 Use the following sequence when t...

Page 95: ...led the offset gain and internal temperature measurements are not performed This increases the measurement speed However the zero gain and tempera ture reference points will eventually drift resulting...

Page 96: ...ssing 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 Figure 3 1 Line cycle synchr...

Page 97: ...s Commands Description Default Autozero command SYSTem AZERo STATe b Enable or disable autozero b ON or OFF ON Line synchronization command SYSTem LSYNc STATe b Enable or disable LSYNC b ON or OFF OFF...

Page 98: ...where S Mainframe slot number 1 2 3 4 or 5 CH Switching module channel number must be 2 digits Examples 101 Slot 1 Channel 1 101 203 Slot 1 Channel 1 and Slot 2 Channel 3 101 110 Slot 1 Channels 1 thr...

Page 99: ...nput divider With the input resistance lowered a more stable 0V reading is achieved with an open input Also some external devices such as a high voltage probe must be terminated to a 10M load The inpu...

Page 100: ...Input 750V RMS 1000V peak 8 x 10 VHz 7 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 DC Voltage Sour...

Page 101: ...n 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 average calculations are cov...

Page 102: ...NG 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 high est voltage that is connected For example if 1000V is co...

Page 103: ...acy including stray signal pick up and thermal offsets Shielding AC voltages that are extremely large compared with the DC signal to be measured may produce an erroneous output Therefore to minimize A...

Page 104: ...be shielded or unshielded as necessary Refer to Shielding page E 9 Widely varying temperatures within the circuit can also create thermal EMFs Therefore maintain constant temperatures to minimize the...

Page 105: ...tion For switching modules it must be in the R in position WARNING To prevent electric shock never make or break connections while power is present in the test circuit Front panel inputs When using th...

Page 106: ...apply more than 3A to the input or the AMPS fuse will blow Model 7700 switching module When performing current measure ments the maximum allowable voltage is 60VDC or 30V RMS Exceeding these limits co...

Page 107: ...r fuse replacement information Resistance measurements 2 and 4 The Model 2750 uses the constant current method to measure resistance from 1 to 1M The Model 2750 sources a constant current I to the res...

Page 108: ...each of the 20 channels can be used to perform 2 measurements For 4 measurements a channel pair is used for each 4 wire measurement as shown in Figure 3 7B For 4 connections channels 1 through 10 whic...

Page 109: ...LO terminals A 2 Connections B 4 Connections Model 2750 Front Panel Shielded Cable Optional Shield Resistance Under Test Model 2750 Front Panel Optional Shield Resistance Under Test Shielded Cable 3A...

Page 110: ...Select the ohms measurement function by pressing 2 or 4 3 Use the RANGE and keys to select a measurement range consistent with the expected resistance or press AUTO to select autoranging AUTO annunci...

Page 111: ...a normal reading is displayed or press AUTO for autorang ing For manual ranging use the lowest possible range for the best resolution 7 To measure other switching channels repeat steps 5 and 6 8 When...

Page 112: ...et compensated ohms can only be performed on the 4 function using the 1 10 100 1k or 10k range Make sure you use 4 wire connections to the DUT see Connections page 3 8 NOTE Make sure the INPUTS switch...

Page 113: ...for the 4 function only Also offset compensated ohms OCOMP can be used with dry circuit ohms to can cel the effect of thermal EMFs Dry circuit ohms applications Measuring contact resistance oxide fil...

Page 114: ...ed on the 4 function using the 1 10 100 or 1k range as follows NOTE Make sure the INPUTS switch is in the correct position To use front panel inputs it must be in the F out position For switching modu...

Page 115: ...aintained at the DUT The voltage is monitored at the Sense HI terminal This allows the Model 2750 to accom modate an additional 80 of range of path resistance per lead So when measuring a 1 resistor t...

Page 116: ...anges The thermocouple voltage equates to a temperature reading This is the basic operation principle of the thermocouple NOTE The equation to calculate thermocouple temperature is provided in Appendi...

Page 117: ...ple 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 reference junction is selected...

Page 118: ...ouple temperature measurement is performed NOTE Channel average cannot be used with thermocouple temperature measurements if open thermocouple detection is enabled Thermistors For thermistors the temp...

Page 119: ...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 in the R in position Thermocouple connection...

Page 120: ...erature of two thermocouple channels using Channel Average see Section 5 for details As shown in Figure 3 8D one thermocouple is connected to a primary channel 1 through 10 and the other thermocouple...

Page 121: ...n Internal Reference Junction Model 7700 Thermocouple Thermocouple Thermocouple C Internal Reference Junction Model 7700 H L CH 1 20 Model 7700 Switching Module Thermocouple Ice Bath Copper wire to th...

Page 122: ...nch 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 Purple French Yellow Green N U S...

Page 123: ...front panel inputs or to any of the 20 input channels of the Model 7700 switching module as shown in Figure 3 9 Figure 3 9 Thermistor connections Model 2750 Input HI Input LO A Front Panel Inputs Ther...

Page 124: ...o 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 channel 11 channel 2 is paired to channel 12 and so on Figure 3 10 4...

Page 125: ...e Model 7700 The INT reference junction setting cannot be selected if there is not at least one INT card installed in the unit With no INT cards installed selecting INT will cause the NO INT CARDS me...

Page 126: ...Beta Delta and at 0 C parameters for the five basic RTD types are provided in Table 3 6 Note that these parameters can be modified using remote programming Table 3 5 Thermistor temperature measurement...

Page 127: ...the R in position 1 If a switching channel is presently closed displayed press OPEN to open it 2 Select the temperature measurement function by pressing TEMP 3 Configure the temperature measurement a...

Page 128: ...riod use a zero crossing trigger meaning that a count is taken when the frequency crosses the zero level The Model 2750 uses a reciprocal counting technique to measure frequency and period This method...

Page 129: ...nputs Model 7700 switching module Connections for the Model 7700 switching module are shown in Figure 3 12 For this 2 wire measurement channels 1 through 20 can be used Figure 3 12 FREQ and PERIOD con...

Page 130: ...apply more than maximum input levels indicated in Figure 3 11 and Figure 3 12 or instrument damage may occur 5 If using a switching module perform the following steps to close the desired channel a P...

Page 131: ...AST 0 1 PLC Limits and digital outputs cannot be used when testing continuity with the conti nuity CONT function If you need to use these operations use the 2 function to test continuity Connections N...

Page 132: ...he ohms reading will be displayed If the measurement is above the threshold level the message OPEN will be displayed 5 To disable continuity testing select a different function i e press DCV NOTE The...

Page 133: ...ent commands 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 A...

Page 134: ...8 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 PT3916 PT385 or USER PT100 e TEMPe...

Page 135: ...ding string FETCh Return reading s READ Trigger and return reading s Channel list parameter clist SCH where S Mainframe slot number 1 2 3 4 or 5 CH Switching module channel number must be 2 digits Exa...

Page 136: ...he 4 function to enable offset compensated ohms and or dry circuit ohms When 4 is selected offset compensated ohms and or dry circuit ohms will be enabled When using the clist parameter to configure a...

Page 137: ...te annunciators are turned off h UNIT TEMPerature name To set temperature measurement units to C use the C or CEL parameter For F use the F or FAR parameter For Kelvin use the K parameter i Trigger an...

Page 138: ...AMPle COUNt which specifies the number of measurements to be performed can be set 1 After INITiate is sent to trigger the measurements FETCh will return the reading strings In general READ performs an...

Page 139: ...T CONT OFF FUNC FRES Select 4 function FRES RANG 1e3 Select 1k range FRES OCOM ON Enable offset compensated ohms READ Trigger and return one reading Example 3 temperature measurement using Model 7700...

Page 140: ...ated 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...

Page 141: ...ing INIT CONT ON sending this query may cause a 213 Init ignored error but will still give a new reading When appropriate If the instrument receives a RST command then it defaults to INIT CONT OFF TRI...

Page 142: ...ete if a reading is in progress The CALC DATA FRESh query is similar to the DATA FRESh query but applies to readings that have math applied to them e g MX B scaling SENSe 1 DATA LATest What it does Th...

Page 143: ...1 READ Enter reading One shot reading DC volts bus trigger auto ranging RST INITiate CONTinuous OFF ABORt TRIGger SOURce BUS SENSe FUNCtion VOLTage DC SENSe VOLTage DC RANGe AUTO ON TRIGger COUNt 1 I...

Page 144: ...Model 2750 Multimeter Switch System User s Manual Basic DMM Operation 3 53 2750 900 01 book Page 53 Wednesday August 3 2011 7 56 AM...

Page 145: ...3 54 Basic DMM Operation Model 2750 Multimeter Switch System User s Manual 2750 900 01 book Page 54 Wednesday August 3 2011 7 56 AM...

Page 146: ...etails on selecting display resolution Includes the commands for remote programming Rate and bandwidth Provides details on integration rate and bandwidth for AC measurements Includes the commands for...

Page 147: ...ange selection for temperature measurements Temperature mea surements are performed on a single fixed range Depending on which type of sensor is being used the maximum temperature readings range from...

Page 148: ...when optimum speed is required Note that the AUTO key has no effect on temperature TEMP Up ranging occurs at 120 of range The Model 2750 will down range when the reading is 10 of nominal range To disa...

Page 149: ...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 2 range n 0 to 120e6 120e6 RES...

Page 150: ...g command sequence configures channel 101 of the Model 7700 to select the 10VDC range when it is scanned FUNC VOLT 101 Set 101 for DCV function VOLT RANG 1 5 101 Set 101 for 10V range Digits The DIGIT...

Page 151: ...to 7 6 RESistance DIGits n clist Set of digits for 2 n 4 to 7 7 FRESistance DIGits n clist Set of digits for 4 n 4 to 7 7 TEMPerature DIGits n clist Set of digits for TEMP n 4 to 7 6 FREQuency DIGits...

Page 152: ...earest integer As implied by the commands in Table 4 3 each mainframe input function can have its own unique digits setting Digits programming examples Example 1 The following commands set digits for...

Page 153: ...panel 0 01 PLC from the bus results in increased reading noise and fewer usable digits while the slowest integra tion time 5 PLC from the front panel 50 PLC from the bus provides the best common mode...

Page 154: ...hile the MEDium and SLOW NPLC settings are ignored see Bandwidth page 4 10 for details From the front panel setting the rate for one function affects all the other functions For example if you set DCV...

Page 155: ...d from 1200 digitized samples 1 2s When the Medium bandwidth 30Hz to 300kHz is chosen the same circuit is used How ever only 120 samples 120ms are needed for an accurate calculation because the analog...

Page 156: ...Set rate for ACV in PLCs n 0 01 to xx 2 5 5 0 VOLTage AC APERture NRf clist Set rate for ACV in secs NRf x to1 3 5 Note 4 CURRent DC NPLCycles n clist Set rate for DCI in PLCs n 0 01 to x 2 5 0 CURRen...

Page 157: ...5 6 30 Channel list parameter clist SCH where S Mainframe slot number 1 2 3 4 or 5 CH Switching module channel number must be 2 digits Examples 101 Slot 1 Channel 1 101 203 Slot 1 Channel 1 and Slot 2...

Page 158: ...ngs conflict error 221 and not be executed For a bandwidth setting of 300 the normal A D conversion method is used therefore the integration rate commands can be used The default bandwidth setting is...

Page 159: ...he average while the repeating filter only averages a stack that is filled with new A D conversions Details on digital filter characteristics are provided as follows Filter count The filter count spec...

Page 160: ...ver age filter uses a first in first out stack When the stack becomes full the measurement conversions are averaged yielding a reading For each subsequent conversion placed in the stack the oldest con...

Page 161: ...quent valid reading will then dis place one of the loaded readings in the stack The FILT annunciator will flash until 10 new readings fill the stack Conversion 10 9 8 7 6 5 4 3 2 1 Conversion Average...

Page 162: ...o display the desired window setting 0 01 0 1 1 10 or NONE and press ENTER 4 Use the and keys to display the number of readings to filter 1 to 100 and press ENTER 5 Use the or key to display the desir...

Page 163: ...set to NONE and if the mov ing 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 set for each channel You cannot set uniq...

Page 164: ...DC AVERage TCONtrol name Select filter type name MOVing or REPeat Note 2 VOLTage DC AVERage WINDow NRf Set filter window in NRf 0 to 10 0 1 VOLTage DC AVERage COUNt n clist Specify filter count n 1 to...

Page 165: ...CURRent AC AVERage TCONtrol name Select filter type name MOVing or REPeat Note 2 CURRent AC AVERage WINDow NRf Set filter window in NRf 0 to 10 0 1 CURRent AC AVERage COUNt n clist Specify filter cou...

Page 166: ...e filter Note 3 Channel list parameter clist SCH where S Mainframe slot number 1 2 3 4 or 5 CH Switching module channel number must be 2 digits Examples 101 Slot 1 Channel 1 101 203 Slot 1 Channel 1 a...

Page 167: ...1 Set filter window to 0 01 CURR AVER COUN 10 Set to filter 10 readings CURR AVER ON Enable filter Example 2 The following command sequence configures channels 101 through 115 of the Model 7700 to use...

Page 168: ...or 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 remote programming to configure...

Page 169: ...ble input for that range For exam ple on the 10V range the Model 2750 still overflows for a 12V input NOTE The various instrument operations including Relative are performed on the input signal in a s...

Page 170: ...gure a scan channel to use rel 1 While in the normal measurement state select the appropriate function and close the appropriate channel For example if scan channel 101 is going to be configured for D...

Page 171: ...to 1010 V 0 VOLTage DC REFerence STATe b clist Enable disable rel b ON or OFF OFF VOLTage DC REFerence ACQuire clist Use input signal as rel value Rel commands for ACV SENSe 1 Optional root command V...

Page 172: ...or 4 SENSe 1 Optional root command FRESistance REFerence n clist Specify rel value n 0 to 120e6 0 FRESistance REFerence STATe b clist Enable disable rel b ON or OFF OFF FRESistance REFerence ACQuire c...

Page 173: ...mmand is VOLT DC REF ACQ Also if the instrument is overflowed OVERFLOW or a read ing has not been triggered an execution error 200 occurs when ACQuire is sent The REFerence n command is coupled to the...

Page 174: ...2 The following command sequence configures channel 101 of the Model 7700 to enable rel and use a 1V rel value when it is scanned FUNC VOLT 101 Select DCV for channel 101 VOLT REF 1 101 Set 1V rel va...

Page 175: ...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 processing sequence that the Mat...

Page 176: ...crement 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 sign the and keys tog gle pol...

Page 177: ...R to dis play 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 decrement the digit value To change...

Page 178: ...reading will be displayed 0 400000 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 The MATH annunciator wil...

Page 179: ...hannels 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 key to select close the input...

Page 180: ...4967295 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 units X CALCulate 1 KMATh PERCent NR...

Page 181: ...n 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 com mand returns the acquired reference value...

Page 182: ...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 101 ROUT CLOS 102 Close chann...

Page 183: ...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 displayed If the Model 2750 i...

Page 184: ...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 key The calculation will disa...

Page 185: ...re 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 chan nel the following setup actions occur a T...

Page 186: ...al root command RATio STATe b clist Enable disable ratio b ON or OFF OFF RATio DELay NRf clist Set delay in secs NRf 0 to 99999 999 0 5 CAVerage STATe b clist Enable disable channel average b ON or OF...

Page 187: ...annel average Ratio and channel average programming examples Example 1 The following command sequence performs the ratio calculation using primary channel 102 of the Model 7700 After READ is sent the...

Page 188: ...ative value of dB is 160dB This will accommodate a ratio of VIN 1 V and VREF 1000V dB configuration Remote programming must be used to configure the Model 2750 for dB measurements It cannot be configu...

Page 189: ...Def DCV dB commands UNITs VOLTage DC name Select DCV measurements name V or DB V UNITs VOLTage DC DB REFerence n Set reference in volts n 1e 7 to 1000 1 ACV dB commands UNITs VOLTage AC name Select A...

Page 190: ...dings and discusses the various statistics available on buffer data including minimum and maximum val ues average mean standard deviation and peak to peak values Remote programming buffer Summarizes t...

Page 191: ...equence that Buffer operations occur Front panel buffer Auto clear With buffer auto clear enabled the buffer is cleared readings lost before a new storage operation starts The buffer can be manually c...

Page 192: ...uffer auto clear press ENTER or EXIT NOTE If you change the state of buffer auto clear the buffer will clear 3 To change the state of buffer auto clear press to place the cursor on the present setting...

Page 193: ...are provided For remote operation the absolute or delta timestamp is returned with each buffer reading The TRACe TSTamp FORMat command selects the relative timestamp type Table 6 1 Real time clock tim...

Page 194: ...ed configuration 2 Press the STORE key 3 Use the and keys to specify the number of readings to store in the buffer 2 to 110000 Pressing the AUTO key sets the readings count to 000000 NOTE With buffer...

Page 195: ...ng or decre menting the buffer reading number by 100 and then finally by 500 When you get close to the desired reading number release the or key Again press and hold in the or key to scroll one readin...

Page 196: ...used to calculate mean where y is the average Xi is a stored reading n is the number of stored readings RDG NO 10 Reading Value Time Date RDG NO 9 Reading Value Time Date RDG NO 8 Reading Value Time D...

Page 197: ...the TRACe command or by front panel data store operation INIT and multi sample READ queries are locked out With readings in the buffer that were stored in that manner you cannot use the INIT or READ c...

Page 198: ...or NONE CALC h TRACe FEED CONTrol name Set buffer control name NEVer NEXT or ALWays NEV h TRACe DATA Read all readings in the buffer i TRACe DATA SELected start count Specify readings to be returned...

Page 199: ...r the buffer SYSTem TSTamp TYPE and TRACe TSTamp TYPE Both of these commands query the timestamp type However SYSTem TSTamp TYPE queries the timestamp that will be used for the next storage operation...

Page 200: ...CALCulate parameter the result of the cal culation is stored in the buffer The NONE parameter disables storage into the buffer Math functions are covered in Section 5 NOTE In order to store readings i...

Page 201: ...ding 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 following command to return the 37...

Page 202: ...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 reading in a TRAC DATA RNUMber is...

Page 203: ...performed on a buffer that has more than 1000 readings the CALCULATING message will flash to indicate that the Model 2750 is busy While busy with the calculation remote program ming commands will not...

Page 204: ...Model 2750 Multimeter Switch System User s Manual Buffer 6 15 2750 900 01 book Page 15 Wednesday August 3 2011 7 56 AM...

Page 205: ...6 16 Buffer Model 2750 Multimeter Switch System User s Manual 2750 900 01 book Page 16 Wednesday August 3 2011 7 56 AM...

Page 206: ...d 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 basic scan a manual external tr...

Page 207: ...ocard in slot 2 SYSTem PCARd3 C7700 Install 7700 pseudocard in slot 3 SYSTem PCARd4 C7700 Install 7700 pseudocard in slot 4 SYSTem PCARd5 C7700 Install 7700 pseudocard in slot 5 Pseudocards for other...

Page 208: ...un in this order 101 102 105 108 109 For remote programming a non sequential scan can be configured Channels are scanned in the order that they are listed in the scan list This allows backward scannin...

Page 209: ...the channel that is presently closed If both a reading AND a scan channel are displayed the reading and annuncia tors pertain to that channel but that channel is no longer closed The next chan nel in...

Page 210: ...l Timer Event Detection Output Trigger Another Reading Trigger Counter Reading Count Yes No Close First Chan in List Open Last Chan Close Next Chan in List Ratio Chan Average Delay Measurement Process...

Page 211: ...ection 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 Trigger Another Reading Yes...

Page 212: ...d the Model 2750 outputs a trigger pulse If programmed to again scan the channels in the scan list the Model 2750 will wait at the control source for another trigger event After all the scan list chan...

Page 213: ...tween scanned channels SCAN operation As shown in Figure 7 2 the timer control source affects the timing between scans It has no effect on the timing between scanned channels External trigger control...

Page 214: ...l average enabled a delay is typically used to keep the channel relays from cycling too fast The default delay period is 0 5 sec onds but can be set from 0 to 999999 999 seconds using remote programmi...

Page 215: ...finity INF the scan will continuously repeat until you stop it NOTE As shown in Figure 7 2 two counters are used for SCAN operation The Trigger counter controls the number of scans and the Sample Coun...

Page 216: ...west numbered channel to the highest Non sequential backward scanning is only intended to be performed using remote programming Unexpected results may occur if a non sequential scan is run from the fr...

Page 217: ...user saved setup SAV0 SAV1 or SAV2 For a front panel configured scan the timer state NO or YES timer value and reading count value are also saved However if the settings for a user setup or power on s...

Page 218: ...arting 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 be...

Page 219: ...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 range Examples SETUP V 1...

Page 220: ...or channel 101 channels 101 through 120 will assume the DCV setup Note that channels for other slots are not affected When you press the 4 function key for a primary channel the subsequently paired ch...

Page 221: ...l able channels that follow will assume the same setup Note however that channels for the other slots are not affected NOTE For the Model 7700 DCI and ACI cannot be selected for module channels 1 thro...

Page 222: ...to 0 001 sec With the desired interval displayed press ENTER Step 5 Set the reading count The displayed reading count RDG CT sets the number channels to scan STEP or the number of scans to run SCAN Y...

Page 223: ...scanned the scan will disable with the monitor channel closed Monitor can be used with limit testing to trigger the start of a scan When the monitor detects that a set reading limit has been reached t...

Page 224: ...r channel also changes When you change the monitor channel while in the normal measurement state the instru ment setup does not change If you want the monitor channel to assume the setup of the scan l...

Page 225: ...nu SAV0 SAV1 and SAV2 A user saved setup can also be used as the power on setup A user saved setup can be restored from the SHIFT SETUP menu Details on user setups are covered in Section 1 Auto scan W...

Page 226: ...s that are turned off will not be scanned 3 Keep in mind that the Timer Delay for STEP occurs between channels while the Timer Delay for SCAN occurs between scans If the timer is off both scans will r...

Page 227: ...buffer the display may not indicate the correct mX B units symbol or annunciator for each channel For example assume one channel used OCOMP ohms while a second used 2 When the read ings are recalled t...

Page 228: ...he 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 length operation loops back...

Page 229: ...ps 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 Advanced scan setup procedure to set up scan channels Wit...

Page 230: ...scan Table 7 1 4 While in the normal measurement state select and enable the monitor channel as explained in see Scan configuration Monitor channel page 7 18 When the reading limit for the monitor cha...

Page 231: ...ude 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 Table 7 1 Control sources...

Page 232: ...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 remote scanning the sample cou...

Page 233: ...number of channels to scan NRf 2 to 110000 Note 3 d ROUTe MONitor STATe b Enable disable monitor b ON or OFF OFF ROUTe MONitor DATA Returns the most recent monitor reading ROUTe CLOSe ACONfigure b Ena...

Page 234: ...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 DATA Read buffer readings TRACe...

Page 235: ...rd to channel 101 NOTES Non sequential scanning is only intended to be performed using remote pro gramming Unexpected results may occur if a non sequential scan is run from the front panel There must...

Page 236: ...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 enabled and triggered ROUT SCAN...

Page 237: ...sample counter 1 see Reference c f INITiate 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 REA...

Page 238: ...hen 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 and trigger cable connections a...

Page 239: ...closes and the Model 2750 waits for an external trigger When the trigger is received channels 101 and 102 are measured Operation then returns to the control source where it waits for another trigger N...

Page 240: ...ure 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 TEMP RJUN RSEL INT 101 b Chan...

Page 241: ...or 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 operation While in the monitor mode...

Page 242: ...re 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 Mode No Yes SCAN Monitor Mode...

Page 243: ...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 Enable Channel Average SHIFT CH AVG CAV ON...

Page 244: ...ations of the instrument External triggering Explains external triggering which allows the Model 2750 to trigger and be triggered by other instruments Remote programming triggering Covers remote opera...

Page 245: ...e instru ment will not stay in idle Operation will continuously fall through the idle state and pro ceed to the Event Detection block of the trigger model When in the one shot trigger mode RST default...

Page 246: ...mmable delay is available after event detection It can be set manually or an auto delay can be used With auto delay selected the instrument automatically selects a delay period that will provide suffi...

Page 247: ...ms 10V 1ms 100V 5ms 1000V 5ms ACV 100mV 400ms 1V 400ms 10V 400ms 100V 400ms 750V 400ms FREQ and PERIOD 100mV 1ms 1V 1ms 10V 1ms 100V 1ms 750V 1ms DCI 20mA 2ms 100mA 2ms 1A 2ms 3A 2ms ACI 1A 400ms 3A 4...

Page 248: ...nversions for a moving average filter is reached After a reading Rdg is procured operation proceeds to Channel Closure Channel Closure When scanning the last device action is channel control The Model...

Page 249: ...line 2 as EXT TRIG The connector pinout is shown in Figure 8 3 Digital I O Pin 6 Ext Trig of the Digital I O can also be used as the external trigger input for the Model 2750 Line 2 of the TRIG LINK i...

Page 250: ...ink input pulse specifications EXT TRIG Voltmeter complete The VMC output provides a TTL compatible output pulse that can be used to trigger other instruments The specifications for this trigger pulse...

Page 251: ...1 DUT 400 DUT 2 Output Card 1 1 2 400 10 7011 MUX Cards Model 2750 MODEL 2750 MULTIMETER SWITCH SYSTEM INTEGRA SERIES SLOT 1 SLOT 3 SLOT 4 SLOT 5 SLOT 2 RANGE AUTO SHIFT LOCAL POWER RANGE EXIT ENTER...

Page 252: ...ngs Model 7002 Factory defaults restored Scan list 1 1 1 400 Number of scans 1 Channel spacing TrigLink Figure 8 7 Trigger link connections Model 2750 IEEE 488 MADE IN U S A CAT I DIGITAL I O TRIG LIN...

Page 253: ...re 8 8 Figure 8 8 Operation model for triggering example A Pressing EX TRIG on the Model 2750 places it at point A in the flowchart where it is waiting for an external trigger B Pressing STEP on the M...

Page 254: ...es the next channel in the scan This triggers the Model 2750 to measure the next DUT The process continues until all 400 channels are scanned measured and stored in the buffer External triggering with...

Page 255: ...be in the idle state whenever operation is at the top of the trigger model As shown in Figure 8 10 initiation needs to be satisfied to take the instru ment out of idle While in the idle state the inst...

Page 256: ...ly 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 the instrument will remain in...

Page 257: ...s 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 Another Trigger Output Trigger A...

Page 258: ...The timer source is only available during scan operation The timer resets to its initial state when the instrument goes into the normal mode of operation or into the idle state EXTernal Event detecti...

Page 259: ...able disable continuous initiation b 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 Select control source IMMediate TIMer MANual...

Page 260: ...use the TRIGger TIMer command to set the interval f DELay AUTO b The auto delay times are listed in Table 8 1 Disabling auto delay sets the delay time to 0 g TRIGger SIGNal Send this action command t...

Page 261: ...8 18 Triggering Model 2750 Multimeter Switch System User s Manual 2750 900 01 book Page 18 Wednesday August 3 2011 7 56 AM...

Page 262: ...of limit tests Remote programming limits and digital output Summarizes the com mands to perform limit tests and control the digital I O port Application sorting resistors Provides an application to t...

Page 263: ...e fac tory 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 Limit 2 can be set to 1V and L...

Page 264: ...ble 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 With this option the beeper s...

Page 265: ...ator each press of or will increase or decrease the reading by a factor of 10 4 Key in the low limit for Limit 1 LO1 and press ENTER 5 Key in the high limit for Limit 2 HI2 and press ENTER 6 Key in th...

Page 266: ...Pin 8 of the digital I O is 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 triggeri...

Page 267: ...2 HI2 Digital Output 5 Master Limit logical OR of the four above limits When a limit LO1 HI2 LO2 or HL2 is reached the digital output line for that limit will be pulled high or low When a reading is...

Page 268: ...o set pulse time and enable disable pulse output are listed in Table 9 2 See Digital output commands in the table The pulse time does not affect measurement speed If a subsequent in limit reading occu...

Page 269: ...e 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 by the device does not excee...

Page 270: ...ays 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 2750 Transistor Switch Flyback Diode Equi...

Page 271: ...es When the out put line is pulled high the transistor will turn off transistor switch open to provide a reli able logic high output 3 75V When the output line goes low the transistor turns on transis...

Page 272: ...n output will be at approximately 5V when a reading is at or exceeds the limit Conversely with active low selected an output will be at 0V when a reading reaches or exceeds the limit MASTR LATCH Use t...

Page 273: ...Use the key to display the present logic sense LSENSE setting HIGH or LOW 6 If you want to retain the present logic sense setting proceed to step 7 Otherwise press to move the cursor to the right pres...

Page 274: ...it 1 test b ON or OFF a CALCulate3 LIMit1 FAIL Query test result 0 pass in 1 fail high or low b CALCulate3 LIMit1 CLEar Clear fail indication c CALCulate3 LIMit1 CLEar AUTO b Enable disable auto clear...

Page 275: ...he 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 operation Commands Description...

Page 276: ...Limit 2 If auto clear is enabled for 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...

Page 277: ...The digital outputs of the Model 2750 can be used to further automate the test system by controlling a compatible component handler to perform the binning operations Limits Limit testing is used to t...

Page 278: ...lustrated 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 pitch beep and the message IN ind...

Page 279: ...outputs With the digital outputs of the Model 2750 enabled the digital outputs will respond as fol lows for each resistor reading Limit 1 result Limit 2 result Resistor tolerance Bin assignment Pass...

Page 280: ...nections General bus commands Describes general bus commands used for fundamen tal GPIB control Front panel GPIB operation Summarizes GPIB error messages status indica tors and using the LOCAL key Pro...

Page 281: ...ever once it is installed you can take the Model 2750 out of remote and use the front panel When the instrument is turned off the pseudocard will be lost uninstalled Autozero Autozero is part of the n...

Page 282: ...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 remote programming See Section 7...

Page 283: ...rd set of commands to control every programmable aspect of an instrument Selecting GPIB and setting primary address The Model 2750 is shipped from the factory with the GPIB selected and the primary ad...

Page 284: ...low many parallel connections to one instrument stack the connectors Two screws are located on each connector to ensure that connections remain secure Present standards call for metric threads which a...

Page 285: ...ocation of the IEEE 488 connector 2 Tighten the screws securely making sure not to overtighten them 3 Connect any additional connectors from other instruments as required for your application 4 Make s...

Page 286: ...addressed to listen IFC Goes into talker and listener idle states LLO LOCAL key locked out GTL Cancel remote restore Model 2750 front panel operation Cancel remote restore front panel operation for al...

Page 287: ...l TALK or LSTN lights if the instrument was previously placed in one of these states Note that this command does not affect the status of the instrument Settings data and event registers are not chang...

Page 288: ...nts instead of clearing all instruments simultaneously as is the case with DCL GET group execute trigger GET is a GPIB trigger that is used as a trigger event to control operation The Model 2750 react...

Page 289: ...n 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 NOTE If LLO is in effect LOCAL w...

Page 290: ...T 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 covered here see the IEEE 488 2 and S...

Page 291: ...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 numeric value parameter can consis...

Page 292: ...IGger 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 query forms are used to determi...

Page 293: ...rmine 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 to command words that exceed...

Page 294: ...ves 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 separated by semicolons The f...

Page 295: ...her 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 message as long as they are...

Page 296: ...re 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 contains four single item query...

Page 297: ...nsmission of buffer readings by pressing LOCAL and then EXIT The next command to send buffer data i e TRACe DATA will start at the begin ning rather than where the transmission was halted Baud rate Th...

Page 298: ...est 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 then there will be no signal...

Page 299: ...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 retain the presently displayed...

Page 300: ...l 2750 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 2750 900 01 book Page 21 Wednesday August 3 2011 7 5...

Page 301: ...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 are not used Table 10 3 PC ser...

Page 302: ...tatus 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 register sets Provides bit...

Page 303: ...he 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 event enable register A cond...

Page 304: ...e 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 Warn 0 2 3 5 6 Cal 7 9 10 11 12...

Page 305: ...s 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 PRESet Reset all bits of the...

Page 306: ...ure 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 con...

Page 307: ...and service request SRQ Service request is controlled by two 8 bit registers the Status Byte Register and the Ser vice Request Enable Register Figure 11 3 shows the structure of these registers Figure...

Page 308: ...ueue 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 that a response message is pre...

Page 309: ...e 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 for exam ple branch to an ap...

Page 310: ...or Queue SRE 4 Enable EAV XYZ Generate error STB Read Status Byte Register Serial poll programming example This example is written specifically for the KPCI 488 2 GPIB card and QuickBasic VisualBasic...

Page 311: ...L 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 Wait for GPIB SRQ line to go tr...

Page 312: ...selected device operations are completed and the Model 2750 is ready to accept new com mands This bit only sets in response to the OPC query command See Section 12 for details on OPC and OPC Figure 11...

Page 313: ...odule types presently installed For details see Defaults and user setups page 1 19 Error 523 Card hardware error Communication with the microprocessor on a switching module card has been lost Error 52...

Page 314: ...nt LL2 Set bit indicates that a reading has reached or exceeded Low Limit 2 Bit B4 High Limit 2 Fail HL2 Set bit indicates that a reading has reached or exceeded High Limit 2 Bit B5 Reading Available...

Page 315: ...at the trace buffer is full Bit B10 Buffer Overflow BOF Set bit indicates that the filled buffer has wrapped and written over previously stored readings Bit B11 Hardware Limit Event HL Set bit indicat...

Page 316: ...6 RAV B5 HL2 B4 LL2 B3 HL1 B2 LL1 B1 ROF B0 OR To Measurement Summary Bit MSB of Status Byte Register ML Master Limit BTF Buffer Three quarter Full BQF Buffer Quarter Full HL Hardware Limit Event BOF...

Page 317: ...ration Summary Cal Set bit indicates that an invalid calibration constant was detected during the power up sequence The instrument will instead use a default calibration constant This error will clear...

Page 318: ...Enable Register Warn Command Warning Cal Calibration Summary Temp Temperature Summary Logical AND OR Logical OR 0 B13 B9 B14 B8 B15 0 Warn Cal Questionable Event Register B13 B9 B14 B8 B15 To Questio...

Page 319: ...nt 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 registers The commands to read t...

Page 320: ...ramming example program and read register set The following command sequence programs and reads the measurement register set Keep in mind that the Model 2750 has to be addressed to talk after a query...

Page 321: ...or 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 message is placed in the Error...

Page 322: ...ed list NOTE To prevent all messages from entering the Error Queue send the enable com mand along with the null list parameter as follows STATus QUEue ENABle Programming example read error queue The f...

Page 323: ...11 22 Status Structure Model 2750 Multimeter Switch System User s Manual 2750 900 01 book Page 22 Wednesday August 3 2011 7 56 AM...

Page 324: ...12 CommonCommands 2750 900 01 book Page 1 Wednesday August 3 2011 7 56 AM...

Page 325: ...er 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 completed B OPT Option que...

Page 326: ...the Model 2750 goes back into the idle state The INIT command operation is not considered finished until the Model 2750 goes back into the idle state See the description for WAI for more information o...

Page 327: ...in the Status Byte Regis ter will set When used with the Initiate Immediately command INITiate a 1 will not be placed into the Output Queue until the Model 2750 goes back into the idle state The INIT...

Page 328: ...0 1 Memory location 1 2 Memory location 2 Use the SAV command to save the present instrument setup configuration in memory for later recall Any control affected by RST can be saved by the SAV command...

Page 329: ...Restore RST defaults TRIG SOUR BUS Select BUS control source TRIG COUN INF Set trigger layer count to infinity INIT Take 2750 out of idle TRG Trigger one measurement H TST self test query Run self te...

Page 330: ...el By sending the WAI command after the TRG command subsequent commands will not executed until the pointer for the Trigger Model has finished moving in response to TRG and has settled at its next sta...

Page 331: ...12 8 Common Commands Model 2750 Multimeter Switch System User s Manual 2750 900 01 book Page 8 Wednesday August 3 2011 7 56 AM...

Page 332: ...13 SCPISignalOriented MeasurementCommands 2750 900 01 book Page 1 Wednesday August 3 2011 7 56 AM...

Page 333: ...econd one is not a clist the first param eter is the range parameter rang and the second is the resolution parameter res The CONFiguration and MEASure commands for the TEMPerature and CON Tinuity func...

Page 334: ...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 100 0 V 3Hdigits The display w...

Page 335: ...measurement and acquire a reading see READ page 13 5 When this command is sent without the clist parameter the Model 2750 will be configured as follows The function specified by this command is select...

Page 336: ...EAD or MEASure com mand is sent NOTES FETCh can repeatedly return the same reading Until there is a new reading this command continues to return the old reading When an instrument setting that is rele...

Page 337: ...AD Trigger and return one reading NOTE When readings are stored in the buffer by the TRACe command or by front panel data store operation INIT and multi sample READ queries are locked out With reading...

Page 338: ...e 1 00000 V 5Hdigits 0 000001 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 an...

Page 339: ...idle state if con tinuous initiation is disabled If continuous initiation is enabled the operation re starts at the beginning of the Trigger Model When CONfigure is executed the MEASure parameters ra...

Page 340: ...Commands FORMat commands Covers the SCPI commands to configure the format that readings are sent over the bus Miscellaneous SYSTem commands Covers miscellaneous SYSTem commands 2750 900 01 book Page 1...

Page 341: ...2 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 only the ASCII format is a...

Page 342: ...the data string for each reading conversion is made up of three 4 byte data blocks Note that the data string for each reading conversion is preceded by a 2 byte header that is the binary equivalent o...

Page 343: ...3 Byte 2 Byte 1 The Header is only sent once for each measurement conversion A Single precision data format 32 data bits s 0 7 0 7 0 7 0 7 0 e f Header Byte 1 Byte 2 Byte 7 Byte 8 Bytes 3 4 5 and 6 n...

Page 344: ...CII 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 when the instrument is turned...

Page 345: ...RMat 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 the data format for each element is sent as...

Page 346: ...m VERSion Read the version of the SCPI standard being used by Model 2750 Example response mes sage 1996 0 SYSTem KEY NRf Parameters 1 SHIFT key 8 FREQ key 2 DCV key 9 3 ACV key 10 4 DCI key 11 RANGE u...

Page 347: ...again selected the beeper will automatically enable Parameters b 0 Disable beeper 1 Enable beeper Figure 14 3 Key press codes SLOT 1 SLOT 3 SLOT 4 SLOT 5 SLOT 2 EXIT ENTER CLOSE OPEN POWER LOCAL SHIF...

Page 348: ...15 SCPIReferenceTables 2750 900 01 book Page 1 Wednesday August 3 2011 7 56 AM...

Page 349: ...optional characters do not have to be included in the program message Do not use brackets in the pro gram message Angle brackets are used to indicate parameter type Do not use angle brackets in the p...

Page 350: ...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 PERCent NRf clist Set target val...

Page 351: ...e 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 limit DATA n clist Set upper lim...

Page 352: ...st Query state of limit test FAIL Query test result 1 failing CLEAR Path to clear events IMMediate Clear high and low events AUTO b Enable or disable auto clear ON AUTO Query auto clear Notes 1 The MM...

Page 353: ...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 Command Description Default pa...

Page 354: ...l others will open Sec 2 STATe clist Query closed channels in specified list 1 closed ACONfigure b Enable or disable auto configure Note 2 ACONfigure Query state of auto configure COUNt clist Query cl...

Page 355: ...easure thermocouple temperature using the internal or external refer ence junction The simulated reference junction will instead be used See Temperature measurements page 3 25 for details Table 15 5 S...

Page 356: ...TO clist Query state of auto range DIGits n clist Specify measurement 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 Ena...

Page 357: ...olution 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 signal as reference REFere...

Page 358: ...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 OFF STATe clist Query state...

Page 359: ...olution 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 signal as reference REFerence...

Page 360: ...st 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 reference OFF STATe clist Query st...

Page 361: ...nce 0 to 120e6 0 Sec 5 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...

Page 362: ...able 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 control filter Sec 4 TCONtrol na...

Page 363: ...ulated 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 FRTD Path to configure 4 wire...

Page 364: ...n clist Select threshold range 0 to 1010 10 RANGe clist Query threshold range PERiod Path to configure period Sec 3 APERture NRf clist Sets gate time for period measurements in seconds 0 01 to 1 0 1 0...

Page 365: ...ated reference temperature TEMPerature RJUNction RSELect name clist Select reference junction SIMulated INTernal or EXTernal TEMPerature RJUNction RSELect clist Query reference junction TEMPerature RJ...

Page 366: ...ead 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 Specify error and status message...

Page 367: ...ON STATe Query state of beeper KCLick b Turn the keyclick on off ON Sec 1 KCLick Query the keyclick status KEY NRf Simulate key press 1 to 31 see Figure 14 3 Sec 14 KEY Query the last pressed key AZER...

Page 368: ...nel Path to query amps channels STARt NRf Request lowest numbered amps channel 0 amps measurements not supported END NRf Request highest numbered amps channel 0 amps measurements not supported AOUTput...

Page 369: ...of banks CSOhms Query whether card supports common side 4 wire ohms i e 7701 TIME hr min sec Set system time using 24 hour format Sec 6 TIME Query system time DATE yr mo day Set system date yr 1999 or...

Page 370: ...Missing will occur 2 The Model 2700 uses a different syntax to specify a slot for the CARD command Instead of using the NRF parameter the slot number is included with the CARD command word i e SYST C...

Page 371: ...lue 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 or DELTa ABS FORMat Query tim...

Page 372: ...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 MANual BUS or EXTernal IMM SOURce...

Page 373: ...o 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 1000 1 REFerence Query reference...

Page 374: ...B Model7700ConnectionGuide 2750 900 01 book Page 1 Wednesday August 3 2011 7 56 AM...

Page 375: ...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 through two protected channels Cha...

Page 376: ...losed See Note 3A 3A To Model 2750 Backplane Channel 25 See Note Backplane Isolation Channel 24 See Note Backplane Isolation Channels 23 and 25 in this schematic refer to the designations used for con...

Page 377: ...nnected at the same time the test lead insulation must be rated to the highest voltage that is connected For example if 1000V is con nected to the front panel input the test lead insulation for the sw...

Page 378: ...crew 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 CH22 AMPS LO H L CH11 H L CH...

Page 379: ...inals Figure B 2 3 Using a small flat blade screwdriver loosen terminal screws and install wires as desired Figure B 4 shows connections to channels 1 and 2 4 Route wire along wire path and secure wit...

Page 380: ...d RTD connections Figure B 7 Current connections AC or DC Figure B 8 Voltage connections AC or DC Figure B 9 Supplementary Insulation CH7 H L CH8 H L CH9 H L CH10 H L H L CH21 H L CH22 AMP S LO H L CH...

Page 381: ...Manual Figure B 5 Thermocouple connections Figure B 6 2 Wire and thermistor connections Channel 1 HI LO Channel 20 HI LO Channels 2 19 Thermocouple Channel 1 HI LO Channel 20 HI LO Channels 2 19 Resi...

Page 382: ...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 4 Wire RTD Resistor or 4 Wir...

Page 383: ...nections 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 needed Channel 1 HI LO Chann...

Page 384: ...700 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 CH14 H L CH15 H L CH16 H L CH...

Page 385: ...B 12 Model 7700 Connection Guide Model 2750 Multimeter Switch System User s Manual 2750 900 01 book Page 12 Wednesday August 3 2011 7 56 AM...

Page 386: ...C StatusandErrorMessages 2750 900 01 book Page 1 Wednesday August 3 2011 7 56 AM...

Page 387: ...ning 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 out of range Settings conflic...

Page 388: ...oo 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 Missing parameter Parameter no...

Page 389: ...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 user selectable event Buffer...

Page 390: ...e 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 error 10m adc full scale er...

Page 391: ...rror 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 4 w dckt Ion zero error 1k...

Page 392: ...ery 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 EE EE EE 522...

Page 393: ...C 8 Status and Error Messages Model 2750 Multimeter Switch System User s Manual 2750 900 01 book Page 8 Wednesday August 3 2011 7 56 AM...

Page 394: ...D SignalProcessing SequenceandDataFlow 2750 900 01 book Page 1 Wednesday August 3 2011 7 56 AM...

Page 395: ...orms 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 to offsets zero and amplifi...

Page 396: ...g 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 Rel ed reading Reading Rel...

Page 397: ...s 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 filtered reading For the repeatin...

Page 398: ...is the reading that is displayed on the Model 2750 With Limits enabled the reading is tested against two sets of high and low limits Along with the displayed reading annunciators and messages are used...

Page 399: ...e paired channel then closes and that reading is used as the Chan B value for the calcu lation Ratio or Ch Avg is then calculated as shown in Figure D 3 As shown the result of Ratio or Ch Avg can then...

Page 400: ...or this triggering configura tion 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 remote operation Min Max Sdev...

Page 401: ...ntinuous initiation and TRIGger COUNt 1 configures the instrument to per form one measurement cycle The INIT command can then be used to initiate the mea surement cycle When the INIT command is sent t...

Page 402: ...ection 14 is used to include the read ing number RNUM element in each data array SENS 1 DATA FRESh This command is similar to DATA LATest in that is also returns the last processed data array stored i...

Page 403: ...to occur To get FETCh working again a new reading must be triggered READ The READ command performs an INITiate and then a FETCh The INITiate triggers a measurement cycle which puts new data in the sa...

Page 404: ...last data array stored in the sample buffer CALC3 LIM1 FAIL CALC3 LIM2 FAIL Each reading applied to the CALC 3 Limit Tests block is tested when Limits operations are enabled When comparing the reading...

Page 405: ...d 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 Continuous measurement mode With...

Page 406: ...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 the scan READ also returns...

Page 407: ...D 14 Signal Processing Sequence and Data Flow Model 2750 Multimeter Switch System User s Manual 2750 900 01 book Page 14 Wednesday August 3 2011 7 56 AM...

Page 408: ...E MeasurementConsiderations 2750 900 01 book Page 1 Wednesday August 3 2011 7 56 AM...

Page 409: ...ts handbook which is available from Keithley Thermoelectric potentials Thermoelectric potentials thermal EMFs are small electric potentials generated by dif ferences in temperature at the junction of...

Page 410: ...r 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 temperatures will differ an...

Page 411: ...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 Unfortunately most good electrical...

Page 412: ...oise 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 lower the temperature 2 red...

Page 413: ...interference RFI Radio Frequency Interference is a general term used to describe electromagnetic interference over a wide range of frequencies across the spectrum Such RFI can be partic ularly trouble...

Page 414: ...power line ground As shown in Figure E 2 the resulting ground loop causes current to flow through the instrument LO signal leads and then back through power line ground This circulating current develo...

Page 415: ...power line ground Ground loops are not normally a problem with instruments like the Model 2750 that have isolated LO terminals However all instruments in the test setup may not be designed in this ma...

Page 416: ...therwise interference from such noise sources as line frequency and RF fields can seriously corrupt measure ments rendering experimental data virtually useless In order to minimize noise a closed meta...

Page 417: ...nce of the Model 2750 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 voltage divider action of RS an...

Page 418: ...ple temperature Thermistor equation Documents the Steinhart Hart equation which is used to calculate thermistor temperature RTD equation Documents the Callendar Van Dusen equation which is used to cal...

Page 419: ...le 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 c3 c4 c5 c6 c7 c8 Error 9 8...

Page 420: ...emperature 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 C 42 919 V to 69 553 V c0 0...

Page 421: ...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 polynomial 200 C to 0 C 3 99...

Page 422: ...1 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 C 235 V to 1 874 V 250 C to...

Page 423: ...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 1 330 447 3 10 16 6 048 144 10 20 c...

Page 424: ...mistor 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 2750 see Table F 9 3 Select a thermistor that closely matches the...

Page 425: ...sistance of a PT100 RTD at 100 C T The following R0 at 0 C alpha beta and delta values are used for the PT100 RTD see Table F 10 T 100 C R0 at 0 C 100 alpha 0 003850 beta 0 10863 delta 1 49990 Using t...

Page 426: ...385 0 10863 1e 8 1 0 000418 1e 8 4 18e 12 The resistance of the RTD at 100 C R100 is then calculated as follows R100 R0 1 AT BT2 CT3 T 100 100 1 0 00391 100 5 77e 7 1002 4 18e 12 1003 100 100 100 1 0...

Page 427: ...F 10 Temperature Equations Model 2750 Multimeter Switch System User s Manual 2750 900 01 book Page 10 Wednesday August 3 2011 7 56 AM...

Page 428: ...G IEEE 488BusOverview 2750 900 01 book Page 1 Wednesday August 3 2011 7 56 AM...

Page 429: ...ransfer The basic handshake sequence between an active con troller talker and a listener is as follows 1 The listener indicates that it is ready to listen 2 The talker places the byte of data on the b...

Page 430: ...and control computer Device 2 able to talk and listen 2750 Device 3 only able to listen printer Device 4 only able to talk DAV NRFD NDAC IFC ATN SRQ REN EOI Data Bus Data Byte Transfer Control Genera...

Page 431: ...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 IEEE 488 standards also includ...

Page 432: ...lled by accepting devices the listener or lis teners receiving the information The three handshake lines are DAV DATA VALID The source controls the state of the DAV line to indicate to any listening d...

Page 433: ...E 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 the purpose of the bus comma...

Page 434: ...T 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 Controlled by external device Lo...

Page 435: ...s 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 commands SRQ Service Reques...

Page 436: ...ke 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 a secondary address group AT...

Page 437: ...strument model defined by the Standard Commands for Programmable Instruments SCPI Consor tium s SCPI standard Generally these commands are sent as one or more ASCII characters that tell the device to...

Page 438: ...YN 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 27 28 29 30 UNL 4 A A B C D E...

Page 439: ...hat 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 instrument is being addressed but i...

Page 440: ...VERSAL 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 LAG LISTEN ADDRESS GROUP MLA...

Page 441: ...ter 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 by the L function Listener...

Page 442: ...igger Function DTI defines the ability of the Model 2750 to have read ings triggered C Controller Function The instrument does not have controller capabilities C0 TE Extended Talker Function The instr...

Page 443: ...G 16 IEEE 488 Bus Overview Model 2750 Multimeter Switch System User s Manual 2750 900 01 book Page 16 Wednesday August 3 2011 7 56 AM...

Page 444: ...settings 8 4 Auto delay times 8 4 Auto scan 7 20 resume scan after power up 7 20 Automatic scan list configuration 7 19 Autoranging 4 3 Autozero 3 4 B Bandwidth 4 10 Basic measurements 3 8 Basic Oper...

Page 445: ...diate 7 8 Timer 7 8 Control sources 7 7 Crest factor 3 12 Limitations 3 12 Current measurements DCI and ACI 3 14 AMPS fuse replacement front panel AMPS input 3 16 Amps measurement procedure 3 15 Conne...

Page 446: ...FREQ and PERIOD connections for front panel inputs 3 39 Frequency and period measurements 3 38 Connections 3 39 Front panel input 3 39 Model 7700 switching module 3 39 Gate time 3 38 procedure 3 40 T...

Page 447: ...nging 4 2 Manual external trigger scan 7 22 Material thermoelectric coefficients E 2 Math 5 8 Basic operation 5 12 Scanning 5 12 commands 5 13 mX b 5 9 mX b configuration 5 9 mX b rel 5 10 Percent 5 1...

Page 448: ...hing modules 1 3 1 6 Power line ground loops E 7 Power module 1 12 1 14 Power up 1 14 Power up sequence 1 16 Pressing REL using rel commands 5 6 program and read register set programming example 11 19...

Page 449: ...isplays 1 17 Filter 4 19 Range 4 4 Rel 5 4 Triggering 8 12 Resistance measurements 2 and 4 3 16 Connections 3 17 Cable leakage 3 17 Front panel inputs 3 17 Model 7700 switching module 3 17 Shielding 3...

Page 450: ...Temperature measurements 3 25 4 wire RTDs 3 28 Connections 3 28 Thermocouple connections 3 28 Thermistors 3 27 Thermocouples 3 25 Open thermocouple detection 3 27 Reference junctions 3 26 External re...

Page 451: ...ical command sequences G 12 U Using common and SCPI commands in the same message 10 16 V Viewing closed channels 2 28 Voltage measurements DCV and ACV 3 8 Connections 3 8 Front panel input 3 9 Model 7...

Page 452: ...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...