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User’s Manual

2700-900-01 Rev. J / August 2011

Model 2700

Multimeter/Switch System

Summary of content (500 pages)

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w w w . k e i th l e y. c o m Model 2700 Multimeter/Switch System User’s Manual 2700-900-01 Rev.
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Safety Precautions 04/09 The following safety precautions should be observed before using this product and any associated instrumentation. Although some instruments and accessories would normally be used with non-hazardous voltages, there are situations where hazardous conditions may be present. This product is intended for use by qualified personnel who recognize shock hazards and are familiar with the safety precautions required to avoid possible injury.
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themselves from the risk of electric shock. If the circuit is capable of operating at or above 1000V, no conductive part of the circuit may be exposed. Do not connect switching cards directly to unlimited power circuits. They are intended to be used with impedancelimited sources. NEVER connect switching cards directly to AC mains. When connecting sources to switching cards, install protective devices to limit fault current and voltage to the card.
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The WARNING heading in the user documentation explains dangers that might result in personal injury or death. Always read the associated information very carefully before performing the indicated procedure. The CAUTION heading in the user documentation explains hazards that could damage the instrument. Such damage may invalidate the warranty. Instrumentation and accessories shall not be connected to humans. Before performing any maintenance, disconnect the line cord and all test cables.
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Table of Contents 1 Getting Started General information ................................................................................. 1-2 Contact information .......................................................................... 1-2 Safety symbols and terms ................................................................. 1-2 Inspection .......................................................................................... 1-3 Options and accessories .............................................
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4-wire functions (paired channels) .................................................... 2-8 Controlling the system channel ......................................................... 2-9 Non-amp and non-measure switching modules .............................. 2-14 Multiple channel operation ..................................................................... 2-16 Controlling multiple channels ......................................................... 2-17 Multiple channel operation anomalies .................
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Thermistors ..................................................................................... 4-wire RTDs .................................................................................... Connections .................................................................................... Temperature measurement configuration ........................................ Temperature measurement procedure ............................................. Frequency and period measurements ...........................
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Relative ..................................................................................................... 5-2 Basic operation .................................................................................. 5-2 Remote programming — rel ............................................................. 5-4 Math .......................................................................................................... 5-8 mX+b ..................................................................................
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Manual/external trigger scan ........................................................... Monitor scan (analog trigger) ......................................................... Remote programming — scanning ........................................................ Trigger model .................................................................................. Channel setup .................................................................................. Buffer ...............................................
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Limits and digital outputs programming example .......................... Application — sorting resistors .............................................................. Limits .............................................................................................. Digital outputs ................................................................................. 10 9-14 9-15 9-15 9-17 Remote Operations Operation enhancements ........................................................................
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Selecting and configuring RS-232 interface ................................. 10-20 RS-232 connections ...................................................................... 10-20 Error messages .............................................................................. 10-22 11 Status Structure Overview ................................................................................................ 11-2 Status byte and SRQ .......................................................................
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SYSTem:VERSion .......................................................................... 14-8 SYSTem:KEY .................................................................... 14-8 SYSTem:BEEPer[:STATe] ..................................................... 14-9 15 SCPI Reference Tables Reference tables ......................................................................................
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[SENS[1]]:DATA:FRESh? ................................................................ D-9 FETCh? ........................................................................................... D-10 READ? ............................................................................................ D-10 MEASure? ...................................................................................... D-10 CALC[1]:DATA[LATest]? .............................................................. D-10 CALC[1]:DATA:FRESh? ..
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Address commands .......................................................................... G-9 Unaddress commands ....................................................................... G-9 Common commands ....................................................................... G-10 SCPI commands ............................................................................. G-10 Command codes ............................................................................. G-10 Typical command sequences ........
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1 Getting Started Quick Start — Of the following section topics, three can be used immediately to quickly acquaint yourself with fundamental instrument operations. Use QS1 to familiarize yourself with front panel controls, use QS2 to power-up the instrument and finally, use QS3 to perform exercises to operate the instrument. • General information — Covers general information that includes, contact information, safety symbols and terms, inspection, and available options and accessories.
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1-2 Getting Started Model 2700 Multimeter/Switch System User’s Manual General information Contact information Worldwide phone numbers are listed at the front of this manual. If you have any questions, please contact your local Keithley representative or call a Keithley Application Engineer at 1-800-348-3735 (U.S. and Canada only).
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Model 2700 Multimeter/Switch System User’s Manual Getting Started 1-3 Inspection Model 2700 was carefully inspected electrically and mechanically before shipment. After unpacking all items from the shipping carton, check for any obvious signs of physical damage that may have occurred during transit. (There may be a protective film over the display lens, which can be removed). Report any damage to the shipping agent immediately. Save the original packing carton for possible future shipment.
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1-4 Getting Started Model 2700 Multimeter/Switch System User’s Manual Model 7701 — This differential multiplexer provides 32 channels of 2-pole input, or 16 channels of 4-pole input. Model 7702 — This differential multiplexer provides 40 channels of 2-pole input, or 20 channels of 4-pole input. It also has two 2-pole channels used exclusively for current input. Model 7703 — This differential multiplexer provides 32 channels of 2-pole input, or 16 channels of 4-pole input.
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Model 2700 Multimeter/Switch System User’s Manual Getting Started 1-5 Cables and connector kits for switching modules Model 7788 DB-50 connector kit — Contains two male DB-50 solder cup connectors with strain relief 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-25 solder cup connectors.
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1-6 Getting Started Model 2700 Multimeter/Switch System User’s Manual Software The following optional software is available from Keithley: ExceLINX-1A – This is an economical, easy-to-use, add-in utility for Microsoft Excel® and Keithley Integra Series Multimeter/Switch systems. No programming is required. Configure your measurements quickly using pop-up menus and eliminate time-consuming and error prone programming.
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Model 2700 Multimeter/Switch System User’s Manual Getting Started 1-7 The Model 2700 has two slots that will accommodate Keithley Model 7700 series switching modules (Table 1-1). Each channel of a switching module that is closed or scanned is measured by the Model 2700. 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 2700 is provided in “DMM measurement capabilities,” page 3-2.
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1-8 Getting Started Model 2700 Multimeter/Switch System User’s Manual Table 1-1 Model 77xx series switching modules Model 7700 2-pole Operation 4-pole Operation 1-pole Operation Measure Volts Measure Amps Measure Ohms Thermocouple Cold Junction Relay Type1 Connector type Configuration2 Unique features 2-pole Operation 4-pole Operation 1-pole Operation Measure Volts Measure Amps Measure Ohms Thermocouple Cold Junction Relay Type1 Connector type Configuration2 Unique features Model 7701 Model 7702 Mode
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Model 2700 Multimeter/Switch System User’s Manual Getting Started 1-9 Table 1-1 (continued) Model 77xx series switching modules 2-pole Operation 4-pole Operation 1-pole Operation Measure Volts Measure Amps Measure Ohms Thermocouple Cold Junction Relay Type1 Connector type Configuration2 Unique features Models 7711 and 7712 Model 7709 Model 7710 8-channels 4 channel pairs N/A 300V maximum No 2/4-wire No 20 channels 10 channel pairs N/A 60V maximum No 2/4-wire Yes N/A N/A 8 channels No3 No3 No3 No3
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1-10 Getting Started Model 2700 Multimeter/Switch System User’s Manual Identifying installed switching modules On power-up, the model numbers of installed switching modules are displayed briefly. If a Model 7700, 7701, 7702, 7703, 7705, 7708, 7709, 7710, 7711, or 7712 switching module is removed while the Model 2700 is on, the instrument will operate as if the module is installed. That is, the Model 2700 will operate as if the pseudocard is installed.
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Model 2700 Multimeter/Switch System User’s Manual Getting Started 1-11 1 Special keys and power switch: SHIFT LOCAL POWER Use to select a shifted function or operation. Cancels GPIB remote mode. Power switch. In position turns 2700 on (I), out position turns it off (O). 2 Function and operation keys: Top Row Unshifted DCV ACV DCI ACI FREQ TEMP Selects DC voltage measurement function. Selects AC voltage measurement function. Selects DC current measurement function.
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1-12 Getting Started Bottom Row Unshifted OPEN CLOSE STEP SCAN DIGITS RATE EXIT ENTER Shifted SAVE SETUP CONFIG HALT TEST LSYNC GPIB RS-232 Model 2700 Multimeter/Switch System User’s Manual Opens closed channel. Closes specified channel. Steps through channels; sends a trigger after each channel. Scans through channels; sends a trigger after last channel. Sets display resolution for all functions. Sets measurement speed (fast, medium, or slow) for all functions.
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Model 2700 Multimeter/Switch System User’s Manual MATH MED MON OCOMP RATIO REAR REL REM SCAN SHIFT SLOW SRQ STAT STEP TALK TIMER TRIG Getting Started 1-13 mX+b, percent, or reciprocal (1/X) calculation enabled. Medium reading rate selected. Monitor channel displayed. 4-wire offset compensated ohms enabled. Channel ratio enabled. Front panel input terminals disconnected. Relative enabled for selected function. Instrument in GPIB remote mode. Scanning operation being performed. Accessing a shifted key.
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1-14 Getting Started Model 2700 Multimeter/Switch System User’s Manual Rear panel summary The rear panel of Model 2700 is shown in Figure 1-2. As shown, a slot cover is installed on slot 2. WARNING Slot covers must be installed on unused slots to prevent personal contact with high voltage circuits. Figure 1-2 Model 2700 rear panel 1 2 4 3 WARNING:NO INTERNAL OPERATOR SERVICABLE PARTS,SERVICE BY QUALIFIED PERSONNEL ONLY. DIGITAL I/O TRIG. LINK ! RS232 MADE IN U.S.A.
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Model 2700 Multimeter/Switch System User’s Manual Getting Started 1-15 Power-up Line power connection Follow the procedure below to connect the Model 2700 to line power and turn on the instrument. 1. Check to see that the line voltage indicated in the window of the fuse holder assembly (Figure 1-3) is correct for the operating voltage in your area. If not, refer to “Setting line voltage and replacing fuse,” page 1-16. CAUTION 2.
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1-16 Getting Started 3. Model 2700 Multimeter/Switch System User’s Manual Connect the female 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 4. The power cord supplied with the Model 2700 contains a separate ground wire for use with grounded outlets. When proper connections are made, instrument chassis is connected to power line ground through the ground wire in the power cord.
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Model 2700 Multimeter/Switch System User’s Manual 4. Getting Started 1-17 Install the fuse holder assembly into the power module by pushing it in until it locks in place. Table 1-2 Fuse ratings Line voltage 100/120V 220/240V Fuse rating 0.25A, slow-blow 5× 20mm 0.125A, slow-blow 5× 20mm Keithley P/N FU-96-4 FU-91 Power-up sequence On power-up, the Model 2700 performs self-tests on its EPROM and RAM and momentarily lights all segments and annunciators.
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1-18 Getting Started Model 2700 Multimeter/Switch System User’s Manual Keyclick With keyclick enabled, an audible click will sound when a front panel key is pressed. Perform the following steps to disable or enable keyclick: 1. 2. Press SHIFT and then LOCAL to display the present state of KEYCLICK (ON or OFF). Press Δ or ∇ to display the desired keyclick state and press ENTER. Remote programming The following command controls keyclick: SYSTem:KCLick ' Enable or disable keyclick.
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Model 2700 Multimeter/Switch System User’s Manual NOTE Getting Started 1-19 Optional command words and queries are not included in Table 1-3. Table 15-2 provides an unabridged list of all display commands. Table 1-3 Display commands Command Description DISPlay:TEXT:DATA Define message ( = ASCII characters, up to 12). DISPlay:TEXT:STATe Enable or disable message mode ( = ON or OFF). DISPlay:ENABle Enable or disable the front panel display ( = ON or OFF).
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1-20 Getting Started Model 2700 Multimeter/Switch System User’s Manual Defaults and user setups Model 2700 can be restored to one of two default setup configurations (FACTory or *RST), or four user-saved (SAV0, SAV1, SAV2, or SAV3). As shipped from the factory, Model 2700 powers up to the factory (FACT) default settings. NOTE Closed channels can be saved in a user setup (SAV0, SAV1, SAV2, or SAV3). When the setup is restored, those channels (and only those channels) will be closed.
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Model 2700 Multimeter/Switch System User’s Manual Getting Started 1-21 Saving and restoring setups Saving a user setup 1. 2. 3. 4. Configure Model 2700 for the desired measurement application. Press SHIFT and then SAVE to access the save setup menu. Press to place the cursor on the present setup (SAV0, SAV1, SAV2, SAV3). Use the Δ or ∇ key to display the desired setup and press ENTER. The instrument returns to the normal measurement state. Saving a power-on setup 1. 2. 3. 4. 5.
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1-22 Getting Started Model 2700 Multimeter/Switch System User’s Manual Table 1-4 Default settings Setting Auto channel configuration Autozero Buffer Auto clear Channel Average Closed channels Closure count interval Continuity Beeper Digits Range Rate Threshold level Current (AC and DC) Bandwidth (AC) Digits (AC) Digits (DC) Filter Window Count Type Range Rate (DC) Rel Frequency and Period Digits Range Rate (aperture) Rel Function GPIB Address Keyclick Factory *RST No (off) On No effect Yes (on) Off No
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Model 2700 Multimeter/Switch System User’s Manual Getting Started 1-23 Table 1-4 (continued) Default settings Setting Limits LO Limit 1 HI Limit 1 LO Limit 2 HI Limit 2 Line Synchronization Math mX+B Scale Factor Offset Units Percent Reference 1/X (Reciprocal) Monitor Output Beeper Digital Output Logic Sense Pulse Ratio Resistance (Ω2 and Ω4) Digits Filter Window Count Type Offset compensation (OCOMP) Range Rate Rel Factory *RST Off -1 +1 -2 +2 Off Off -1 +1 -2 +2 Off Off 1.0 0.0 “X” Off 1.
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1-24 Getting Started Model 2700 Multimeter/Switch System User’s Manual Table 1-4 (continued) Default settings Setting RS-232 Baud rate Flow control Terminator Scanning Auto scan Type (Simple or Advanced) Simple scan Minimum channel Maximum channel Timer Reading count Advanced scan Setup Immediate trigger Limit triggers Timer Reading count Temperature Digits Filter Window Count Type Rate Rel Sensor Junction Open detector Type Units Timestamp Triggering Delay Source Reading hold Window Count Factory *RST
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Model 2700 Multimeter/Switch System User’s Manual Getting Started 1-25 Table 1-4 (continued) Default settings Setting Factory Voltage (AC and DC) dB Reference Digits (AC) Digits (DC) Filter Window Count Type Range Rate (DC) Rel Off 1.0 5Hdigits 6Hdigits On 0.1% 10 Moving Auto Slow (5 PLC) Off *RST Set Diff Off 1.0 5Hdigits 6Hdigits Off 0.1% 10 Repeat Auto Slow (5 PLC) Off ✓ ✓ Note: With a Model 7700, 7706, or 7708 installed, the default sensor junction is Internal.
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1-26 Getting Started Model 2700 Multimeter/Switch System User’s Manual Remote programming information Remote programming information is integrated with front panel operation throughout this manual. Programming commands are listed in tables, and additional information that pertains exclusively to remote operation is provided after each table. The tables may reference you to other sections of this manual. NOTE Except for Sections 11 through 15, most programming tables in this manual are abridged.
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Model 2700 Multimeter/Switch System User’s Manual Getting Started 1-27 Basic DMM measurements — front panel inputs NOTE See Section 3 for details on basic DMM operation. The Model 2700 is shipped from the factory to power-up to factory defaults. The instrument powers up to a setup that continuously measures DC volts. Some of the default settings for the DCV function include auto range enabled, 6H-digit resolution, filter enabled, and slow reading rate.
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1-28 Getting Started Model 2700 Multimeter/Switch System User’s Manual Exercise 1 — Basic DMM measurements The exercise in Table 1-6 measures ACV on the 10V range and stores 15 readings in the buffer. Table 1-6 Exercise 1—Measure AC volts - store readings in buffer Front panel operation 1 2 3 4 6 Command sequence For front panel operation, proceed to step 2. For remote programming, clear the buffer1: TRAC:CLE Restore defaults2: Press SHIFT > press SETUP > select RESTORE: FACT.
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Model 2700 Multimeter/Switch System User’s Manual Getting Started 1-29 Closing and opening channels — system channel operation NOTE See Section 2 for details on closing and opening switching module channels. NOTE The following discussion assumes a multiplexing switching module (i.e., Model 7700) is installed in slot 1 of the mainframe. Switching module installation is covered in Section 2 (see “Switching module installation and connections,” page 2-3).
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1-30 Getting Started • Model 2700 Multimeter/Switch System User’s Manual For a 4-wire function (i.e., Ω4), a channel pair is connected to the DMM when a system channel is closed. The system channel is connected to DMM Input and the paired channel is connected to DMM Sense. Figure 1-5 shows system channel 6 closed. For a 4-wire function, the paired channel also closes. For the Model 7700, channels 1 through 10 are paired to channels 11 through 20. When channel 6 is closed, channel 16 also closes.
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Model 2700 Multimeter/Switch System User’s Manual • • • Getting Started 1-31 When a system channel is closed, the channel number will be displayed on the Model 2700. 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 the system channel number is displayed.
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1-32 Getting Started Model 2700 Multimeter/Switch System User’s Manual Exercise 2 — Closing and opening channels (system channel operation) The exercise in Table 1-7 demonstrates a sequence to close and open channels of a Mode 7700 installed in slot 1 of the mainframe. Table 1-7 Exercise 2 — Close and open channels (system channel operation) Front panel operation 1 2 3 4 5 6 7 Command sequence Open all channels*: Press OPEN > display OPEN:ALL > Press OPEN.
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Model 2700 Multimeter/Switch System User’s Manual Getting Started 1-33 For SCAN, the reading count also determines the number of scans to perform and is best explained by an example. Assume 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 performed. If you set the reading count to any value from 11 to 20, two scans will be performed. A reading count from 21 to 30 gives you three scans, and so on.
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1-34 Getting Started Model 2700 Multimeter/Switch System User’s Manual For remote programming, the following commands are used for simple scanning: ROUTe:SCAN TRIGger:COUNt SAMPle:COUNt ROUTe:SCAN:LSELect ' Define scan list*. ' Specify number of scans (1 to 11000 or INFinity). ' Specify number of channels to scan (1 to 11000). ' Enable (INT) or disable (NONE) scan. * Any valid switching module channel can be included in the scan list.
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Model 2700 Multimeter/Switch System User’s Manual Getting Started 1-35 Trigger and return readings — remote programming There are several commands used to trigger and return readings. The proper commands and sequence to use depend on the trigger state (continuous or non-continuous) and what you are trying to accomplish. Presented here are three fundamental command sequences that can be used to “trigger and return readings.
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1-36 Getting Started Model 2700 Multimeter/Switch System User’s Manual Exercise 4 — Trigger and return a single reading Exercise 5 — Trigger and return multiple readings Trigger controlled measurements — The instrument is typically used in a noncontinuous trigger mode. In this mode, commands are used to trigger one or more readings. After the specified number of readings are completed, the measurement process stops. Exercise 4 in Figure 1-8 provides a command sequence to trigger and return one reading.
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Model 2700 Multimeter/Switch System User’s Manual Getting Started Figure 1-9 Exercise 5 — Trigger and return multiple readings TRAC:CLE INIT:CONT OFF TRIG:COUN 1 Trigger Configuration SAMP:COUN x Clear buffer1 Place 2700 in non-continuous trigger state Set 2700 to perform “x” number of measurements (x = 2 to 110000) INIT Trigger and Return OR READ? FETCh? Readings2, 3 Trigger and Return Readings TRAC:DATA? Return Stored Readings4 1.
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1-38 Getting Started Model 2700 Multimeter/Switch System User’s Manual Figure 1-10 Exercise 6 — Return a single reading (continuous triggering) Trigger Configuration Return Readings SAMP:COUN 1 INIT:CONT ON FETCh? OR CALC:DATA? Return result of MATH calculation1, 2 Place 2700 in continuous trigger state. DATA? OR DATA:FRESh? Return Basic Reading2, 3 1. If a MATH function (mX+B, percent or 1/X) is enabled, the result of the calculation will be returned.
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2 Closing and Opening Switching Module Channels • Close/open overview — Summarizes the two operating modes to control switching modules: System channel operation and multiple channel operation. • Switching module installation and connections — Explains how to install a switching module (or pseudocard) into the Model 2700 mainframe. Also explains where to find connection information which should only be performed by qualified service personnel.
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2-2 Close/Open Switching Module Channels Model 2700 Multimeter/Switch System User’s Manual Close/open overview NOTE This section covers basic close/open operations for switching module channels. It also covers the operating characteristics that are unique to the Model 7700 switching module. There are two modes of close/open operation: • • System channel operation — This is the mode of operation that should be used exclusively by most (if not all) users.
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Model 2700 Multimeter/Switch System User’s Manual Close/Open Switching Module Channels 2-3 Switching module installation and connections In order to exercise close/open operations explained in this section, a switching module (or pseudocard) must be installed in the mainframe. A switching module can be installed by the user, however external connections to the switching module are only to be performed by qualified service personnel.
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2-4 Close/Open Switching Module Channels Model 2700 Multimeter/Switch System User’s Manual Connections WARNING Connection information for switching modules is intended for qualified service personnel. Do not attempt to connect DUT or external circuitry to a switching module unless qualified to do so.
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Model 2700 Multimeter/Switch System User’s Manual Close/Open Switching Module Channels 2-5 Pseudocards Using remote programming, you can assign a pseudocard to an empty switching module slot. With a pseudocard installed, the Model 2700 will operate as if the switching module is installed in the Model 2700. This feature allows you exercise open/close/scan operations, or configure your system without having the actual switching module installed in the unit.
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2-6 Close/Open Switching Module Channels Model 2700 Multimeter/Switch System User’s Manual System channel operation The system channel is a closed measurement channel that is internally connected to the internal DMM Input of the Model 2700. The system channel number is displayed on the Model 2700. For a 4-wire function (i.e., Ω4), the paired channel for the system channel is internally connected to DMM Sense. The paired channel is not displayed on the Model 2700.
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Model 2700 Multimeter/Switch System User’s Manual Close/Open Switching Module Channels 2-7 2-wire functions Figure 2-1 shows an example of how the system channel is connected to the DMM Input of the Model 2700. Assume a Model 7700 switching module is installed in slot 1 of the mainframe. When channel 101 is closed using the system channel close keys, both the Channel 1 relay and the backplane isolation relay (Channel 25) close to connect the channel to the DMM.
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2-8 Close/Open Switching Module Channels Model 2700 Multimeter/Switch System User’s Manual 4-wire functions (paired channels) A 4-wire function, such as Ω4, requires that another measurement channel be paired to the system channel. For example, if the switching module has 20 measurement channels, channels 1 through 10 can be used as the system channel, while channels 11 through 20 are used as the paired channel.
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Model 2700 Multimeter/Switch System User’s Manual Close/Open Switching Module Channels 2-9 Controlling the system channel When a measurement channel is closed, a previous system channel (and, for a 4-wire function, its paired channel) is first opened. The closed measurement channel becomes the system channel. When a 4-wire function is selected, the paired channel for the system channel also closes.
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2-10 Close/Open Switching Module Channels Model 2700 Multimeter/Switch System User’s Manual CLOSE key (SINGLE menu option) The SINGLE menu option for the CLOSE key can be used to select a measurement channel as the system channel (Figure 2-4). Perform the following steps to select the system channel: 1. Press the CLOSE key. The “CLOSE:SINGLE” message will be displayed. NOTE 2. 3. 4.
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Model 2700 Multimeter/Switch System User’s Manual Close/Open Switching Module Channels 2-11 OPEN key (ALL menu option) The ALL menu option of the OPEN key opens all channels for all switching modules installed in the Model 2700 (Figure 2-5). For example, if a Model 7700 switching module is installed in slot 1, OPEN: ALL 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).
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2-12 Close/Open Switching Module Channels Model 2700 Multimeter/Switch System User’s Manual Remote programming — system channel control commands The commands to close and open the system channel are listed in Table 2-1. When a system channel reading is returned, the system channel number will be included in the data string if the CHANnel data element is selected. The FORMat:ELEMents command is used to specify the data elements to be included in the data string (see FORMat commands in Section 14).
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Model 2700 Multimeter/Switch System User’s Manual c. Close/Open Switching Module Channels 2-13 ROUTe:CLOSe? This query command returns a of closed measurement channels, including paired channels for 4-wire functions. This query command will not return non-measurement channels, such as backplane isolation channels and the pole-mode channel. d. ROUTe:OPEN:ALL This command functions the same as the front panel OPEN key (ALL menu option).
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2-14 Close/Open Switching Module Channels Model 2700 Multimeter/Switch System User’s Manual Non-amp and non-measure switching modules There are Keithley switching modules that do not support current measurements and there are modules that do not support any measurements at all. Non-amps module — With an amps function selected (DCI or ACI), system channel operation cannot be used to close channels on that module.
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Model 2700 Multimeter/Switch System User’s Manual Close/Open Switching Module Channels 2-15 Non-measure switching modules NOTE Presently, non-measure Keithley modules include the Models 7705, 7711, and 7712. You can check the Keithley website (www.keithley.com) for new modules. Keep the following in mind when using a non-measure module: • • • • • For a non-measure card, no channels are connected to the internal DMM (the channels cannot be connected to the backplane).
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2-16 Close/Open Switching Module Channels Model 2700 Multimeter/Switch System User’s Manual Multiple channel operation The capability to individually control channels provides you with added flexibility in how you use a switching module. For example, assume you want to route a signal into channel 1 and out channel 20 of a Model 7700 switching module. You would do this by closing channels 1, 20, and 23. If you open channels 24 and 25, you will isolate the input signal from the DMM of Model 2700.
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Model 2700 Multimeter/Switch System User’s Manual Close/Open Switching Module Channels 2-17 Controlling multiple channels WARNING When using multiple channel operation, you must be very careful when switching hazardous voltages. If you inadvertently close the wrong channel(s), you could create a shock hazard and/or cause damage to the equipment. Most switching modules use latching relays. That is, closed channels remain closed when the Model 2700 is turned off.
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2-18 Close/Open Switching Module Channels Model 2700 Multimeter/Switch System User’s Manual CLOSE key (MULTI menu option) The MULTI menu option for the CLOSE key can be used to close any individual channel in the mainframe (Figure 2-6). Perform the following steps to close a channel: NOTE 1. 2. 3. 4. Channels closed by the MULTI option of the CLOSE key are not displayed. Use the VIEW option of the CARD menu to display closed channels (see “CARD menu,” page 2-29).
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Model 2700 Multimeter/Switch System User’s Manual Close/Open Switching Module Channels 2-19 OPEN key The OPEN key has two options to open channels: ALL and MULTI. The ALL option simply opens all channels in the mainframe. The MULTI option opens only the specified channel. All other closed channels remain closed. Figure 2-7 summarizes OPEN key operation. OPEN: ALL — Perform the following steps to open all channels in the mainframe: 1. 2. Press the OPEN key to display “OPEN: ALL.
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2-20 Close/Open Switching Module Channels Model 2700 Multimeter/Switch System User’s Manual Remote programming — Multiple channel control commands The commands to close and open the system channel are listed in Table 2-2. Table 2-2 Multiple channel control commands Commands ROUTe:MULTiple:CLOSe ROUTe:MULTiple:OPEN ROUTe:OPEN:ALL ROUTe:MULTiple:CLOSe? ROUTe:MULTiple:CLOSe:STATe? Description Ref Specify one or more channels to close. Open channels specified in list.
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Model 2700 Multimeter/Switch System User’s Manual b. d. e. 2-21 ROUTe:MULTiple:OPEN With this command, you can open one or more switching module channels. When you send this command to open the channels specified in the , only those listed channels will open. Channels not specified are not affected. NOTE c. Close/Open Switching Module Channels For RS-232 operation (and in some cases, GPIB operation), *OPC or *OPC? should be used with :ROUT:MULT:OPEN if the is large.
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2-22 Close/Open Switching Module Channels Model 2700 Multimeter/Switch System User’s Manual Multiple channel operation anomalies • • NOTE Anomaly #1 — When you use multiple channel operation to open the system channel, the channel will open but the system channel number will still be displayed on the Model 2700. For details, see “Anomaly #1 example — wrong channel displayed.” Anomaly #2 — For a 4-wire function, you can use multiple channel operation to open the paired channel.
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Model 2700 Multimeter/Switch System User’s Manual Close/Open Switching Module Channels 2-23 Anomaly #2 example — opening the paired channel Assume 4-wire connections to a 1kΩ resistor using channels 1 and 11 of the Model 7700 switching module. Also assume the Ω4 function is selected. The following procedure demonstrates how careless multiple channel operation can cause an overflow reading even though everything else from the front panel “looks right.” 1. 2. 3. 4.
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2-24 Close/Open Switching Module Channels Model 2700 Multimeter/Switch System User’s Manual Dual independent multiplexers Using multiple channel operation, any multiplexer switching module can be configured as two independent multiplexers. For example, the Model 7700 is normally used as a single 1 × 20 multiplexer, but it can also be configured as two 1 × 10 multiplexers.
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Model 2700 Multimeter/Switch System User’s Manual Close/Open Switching Module Channels 2-25 Dual multiplexer application This application demonstrates how to use the Model 7700 as a dual multiplexer to bias and measure 10 DUT. An external source powers DUT, while the DMM of the Model 2700 measures the output of the DUT. To prevent overloading of the external source, each DUT is powered (and measured) separately. Figure 2-9 shows the connections for this application.
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2-26 Close/Open Switching Module Channels Model 2700 Multimeter/Switch System User’s Manual For this application, the 2-pole/4-pole relay and backplane isolation relays of the switching module are to be controlled as follows: • • • Closing channel 23 connects the External Source to DUT via channels 11 through 20. Closing channel 23 also isolates measure channels (1 through 10) from the source channels (11 through 20). This channel must remain closed while testing DUT.
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Model 2700 Multimeter/Switch System User’s Manual Close/Open Switching Module Channels 2-27 Figure 2-10 Testing DUT 1 Model 2700 Model 7700 Switching Module HI External Source Sense DUT 1 LO Slot 1 HI HI Ch 25 Ch 1 LO LO DMM Ch 23 (Closed) HI HI Ch 24 Ch 11 LO Mutliple channel operation: Open channels Close channel 123 Close channel 125 Close channel 101 Close channel 111 1. 2. Input Sense LO External Source DUT 1 DMM Equivalent Circuit Open all channels.
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2-28 Close/Open Switching Module Channels 3. 4. 5. 6. 7. 8. Model 2700 Multimeter/Switch System User’s Manual Close channels 1 and 11 to connect DUT #1 to the DMM and bias supply. Front panel operation: Press CLOSE > Select MULTI > Key in 101 > Press ENTER Press CLOSE > Select MULTI > Key in 111 > Press ENTER Remote programming: ROUT:MULT:CLOS (@101,111) Measure DUT #1. Front panel operation: Take reading from display Remote programming: DATA? Open channels 1 and 11.
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Model 2700 Multimeter/Switch System User’s Manual Close/Open Switching Module Channels 2-29 CARD menu The CARD menu identifies the switching modules installed in the mainframe, and is used for 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 channels that are presently closed.
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2-30 Close/Open Switching Module Channels Model 2700 Multimeter/Switch System User’s Manual SLOTX: 77XX — Use to configure the switching module in Slot X (where X = 1 or 2). If configuration is not necessary, the instrument will exit from the menu when ENTER is pressed. NOTE For switching modules that require configuration, refer to packing list that was shipped with each module. CARD: VIEW — This menu item is used to view all analog input channels that are presently closed.
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Model 2700 Multimeter/Switch System User’s Manual Close/Open Switching Module Channels 2-31 Switching module queries (remote operation) For remote operation, there are commands to identify installed switching modules and channels that are closed. There are also commands to acquire general information about the installed modules. *OPT? For remote operation, the *OPT? command can be used to determine which switching modules (or pseudocards) are installed in the Model 2700.
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2-32 Close/Open Switching Module Channels Model 2700 Multimeter/Switch System User’s Manual Relay closure count The Model 2700 keeps an internal count of the number of times each module relay has been closed. The total number of relay closures are stored in EEPROM on the card. This count will help you determine if and when any relays require replacement (see module contact life specifications). Relay closures are counted only when a relay cycles from open to closed state.
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Model 2700 Multimeter/Switch System User’s Manual Close/Open Switching Module Channels 2-33 Reading relay closure count To determine the closure count of specific channels, send this query via remote: ROUTe:CLOSe:COUNt? Here, is the summary of channels.
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2-34 Close/Open Switching Module Channels Model 2700 Multimeter/Switch System User’s Manual Model 7700 switching module NOTE Connection and wiring procedures for the Model 7700 are to be performed by qualified service personnel. This information is provided in Appendix B (Model 7700 Connection Guide). Switching module capabilities Channels 1 through 20 — The Model 7700 can multiplex one of 20 2-pole signals, or one of 10 4-pole signals into the input of the Model 2700.
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Model 2700 Multimeter/Switch System User’s Manual Close/Open Switching Module Channels 2-35 The 2-wire functions include DCV, ACV, DCI, ACI, Ω2, CONT, FREQ, PERIOD, and TEMP (thermocouple and thermistor). The 4-wire functions/operations include Ω4, TEMP (4-wire RTD), RATIO, and CH AVG (ratio and channel average are covered in Section 5).
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2-36 Close/Open Switching Module Channels Model 2700 Multimeter/Switch System User’s Manual Figure 2-12 Model 7700 simplified schematic Input HI LO Sense HI LO Cold Junction Ref x3 Channel 1 HI LO Channel 25 (See Note) Backplane Isolation (Channels 2–9) HI HI Input LO Channel 10 LO Channel 23 2-Pole (Open) 4-Pole (Closed) (See Note) Cold Junction Ref x3 Channel 11 Channel 24 (See Note) Backplane Isolation HI Sense LO HI LO To Model 2700 Backplane (Channels 12–19) HI Channel 20 LO 3A AMPS HI
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3 Basic DMM Operation • DMM measurement capabilities — Summarizes the measurement capabilities of the Model 2700 and covers maximum signal levels for switching modules. • High energy circuit safety precautions — Provides safety information when performing measurements in high energy circuits. • Performance considerations — Covers some considerations that affect overall performance including warm-up, autozero, and line synchronization.
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3-2 Basic DMM Operation Model 2700 Multimeter/Switch System User’s Manual DMM measurement capabilities NOTE Accuracy specifications for all measurement functions and the Model 7700 switching module are provided in Appendix A. The DMM of the Model 2700 can make the following measurements: DCV — DC voltage measurements from 0.1µV to 1000V. ACV — AC voltage measurements from 0.1µV to 750V. DCI — DC current measurements from 10nA to 3A. ACI — AC current measurements from 1µA to 3A.
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Model 2700 Multimeter/Switch System User’s Manual Basic DMM Operation 3-3 High energy circuit safety precautions To optimize safety when measuring voltage in high energy distribution circuits, read and use the directions in the following warning. WARNING Dangerous arcs of an explosive nature in a high energy circuit can cause severe personal injury or death. If the multimeter is connected to a high energy circuit when set to a current range or low resistance range, the circuit is virtually shorted.
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3-4 Basic DMM Operation Model 2700 Multimeter/Switch System User’s Manual Performance considerations Warm-up After the Model 2700 is turned on, it must be allowed to warm up for at least two hours to allow the internal temperature to stabilize. If the instrument has been exposed to extreme temperatures, allow extra warm-up time.
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Model 2700 Multimeter/Switch System User’s Manual Basic DMM Operation 3-5 LSYNC (line cycle synchronization) Synchronizing A/D conversions with the frequency of the power line increases common mode and normal mode noise rejection. When line cycle synchronization is enabled, the measurement is initiated at the first positive-going zero crossing of the power line cycle after the trigger. Figure 3-1 shows the measurement process that consists of two A/D conversions.
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3-6 Basic DMM Operation Model 2700 Multimeter/Switch System User’s Manual Remote programming — autozero and LSYNC Autozero and LSYNC commands The commands to control display resolution (digits) are listed in Table 3-1.
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Model 2700 Multimeter/Switch System User’s Manual Basic DMM Operation 3-7 Throughout this manual, you will encounter commands that can use the parameter. The simply indicates that the associated command can be used to configure a scan channel. For example: SENSe:FUNCtion 'VOLTage:AC' SENSe:FUNCtion 'VOLTage:AC',(@101) ' Select ACV function. ' Configure scan channel 101 for ACV. While in the normal measurement display state, the first command simply selects the ACV function.
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3-8 Basic DMM Operation Model 2700 Multimeter/Switch System User’s Manual Connections WARNING NOTE Even though the Model 2700 can measure up to 1000V peak, the maximum input to a switching module is less. Exceeding the voltage rating of a switching module may cause damage and create a safety hazard. 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.
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Model 2700 Multimeter/Switch System User’s Manual Basic DMM Operation Figure 3-2 DCV and ACV connections using front panel inputs Model 2700 SENSE Ω 4 WIRE INPUT HI 350V PEAK ! LO 500V PEAK INPUTS F FF DC Voltage Source 1000V PEAK R FRONT/REAR 3A 250V AMPS Input Resistance = 10MΩ on 1000V and 100V ranges; >10GΩ on 10V, 1V, and 100mV ranges. Caution: Maximum Input = 1000V peak A.
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3-10 Basic DMM Operation Model 2700 Multimeter/Switch System User’s Manual Model 7700 switching module Connections for the Model 7700 switching module are shown in Figure 3-3. For basic DCV and ACV measurements (Figure 3-3A and B), channels 1 through 20 can be used. Ratio and channel average calculations — Ratio calculates the reading ratio of two channels, while channel average calculates the reading average of two channels. For these calculations, paired switching channels are used.
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Model 2700 Multimeter/Switch System User’s Manual Basic DMM Operation 3-11 Volts measurement procedure NOTE 1. 2. 3. 4. 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 modules, it must be in the “R” (in) position. If a switching channel is presently closed (displayed), press OPEN to open it. Select the volts measurement function by pressing DCV or ACV.
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3-12 Basic DMM Operation Model 2700 Multimeter/Switch System User’s Manual AC voltage measurements and crest factor The root-mean-square (RMS) value of any periodic voltage or current is equal to the value of the DC voltage or current which delivers the same power to a resistance as the periodic waveform does. Crest factor is the ratio of the peak value to the RMS value of a particular waveform. The crest factor of various waveforms is different, since the peak-to-RMS ratios are variable.
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Model 2700 Multimeter/Switch System User’s Manual Basic DMM Operation 3-13 Additional error uncertainties are also specified for non-sinusoidal waveforms of specific crest factors and frequencies. The Model 2700 has capabilities of measuring AC waveforms of crest factors up to 5.
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3-14 Basic DMM Operation Model 2700 Multimeter/Switch System User’s Manual Figure 3-5 ACV measurements – square, pulse, and sawtooth waves Square VP AC coupled RMS: Crest factor: VRMS = VP 0 CF = 1 -VP Rectified square VP AC coupled RMS: 0 VRMS = VP CF = 2 2 Pulse VP 0 +V AC coupled RMS: VRMS = VP D(1-D) t T where; D (duty cycle) = t 1 D(1-D) T AC coupled peak: AC coupled pulse 0 -V CF = VP +V = VP(1-D) -V = -VPD When; 0 < D £ 0.5: CF = 1 -1 D When; 0.
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Model 2700 Multimeter/Switch System User’s Manual Basic DMM Operation 3-15 Low level considerations For sensitive measurements, external considerations beyond the Model 2700 affect the accuracy. Effects not noticeable when working with higher voltages are significant in microvolt signals. The Model 2700 reads only the signal received at its input; therefore, it is important that this signal be properly transmitted from the source.
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3-16 Basic DMM Operation Model 2700 Multimeter/Switch System User’s Manual Widely varying temperatures within the circuit can also create thermal EMFs. Therefore, maintain constant temperatures to minimize these thermal EMFs. A shielded enclosure around the circuit under test also helps by minimizing air currents. The REL control can be used to null out constant offset voltages.
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Model 2700 Multimeter/Switch System User’s Manual Basic DMM Operation 3-17 Current measurements (DCI and ACI) The Model 2700 can make DCI measurements from 10nA to 3A and ACI measurements from 1µA to 3A RMS. NOTE See the previous discussion about crest factor in “Voltage measurements (DCV and ACV),” page 3-7. Connections NOTE When using the front panel inputs, the INPUTS switch must be in the “F” (out) position. For switching modules, it must be in the “R” (in) position.
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3-18 Basic DMM Operation Model 2700 Multimeter/Switch System User’s Manual Model 7700 switching module Connections for the Model 7700 switching module are shown in Figure 3-7. Note that only channels 21 and 22 can be used for current measurements. Figure 3-7 DCI and ACI connections using Model 7700 switching module H Current Source CH 21 or 22 L Model 7700 Switching Module Caution: Maximum input: 60VDC or 30V RMS, 3A switched, 60W, 125VA maximum Amps measurement procedure NOTE 1. 2. 3. 4.
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Model 2700 Multimeter/Switch System User’s Manual 6. 7. 8. NOTE Basic DMM Operation 3-19 Observe the displayed reading. If the “OVERFLOW” message is displayed, select a higher range until a normal reading is displayed (or press AUTO for autoranging). For manual ranging, use the lowest possible range for the best resolution. To measure another amps channel, repeat steps 5 and 6. When finished, press OPEN if there is a channel closed.
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3-20 Basic DMM Operation Model 2700 Multimeter/Switch System User’s Manual Resistance measurements (Ω2 and Ω4) The Model 2700 uses the constant-current method to measure resistance from 100Ω to 1MΩ. The Model 2700 sources a constant current (I) to the resistance and measures the voltage (V). Resistance (R) is then calculated (and displayed) using the known current and measured voltage (R = V/I). For the 10MΩ and 100MΩ ranges, the ratiometric method is used to measure resistance.
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Model 2700 Multimeter/Switch System User’s Manual Basic DMM Operation Figure 3-8 Ω2 and Ω4 connections for front panel inputs Model 2700 SENSE Ω 4 WIRE Shielded Cable INPUT HI 350V PEAK 1000V PEAK ! LO 500V PEAK INPUTS F FF Optional Shield Resistance Under Test R FRONT/REAR 3A 250V AMPS Note: Source current flows from the INPUT HI to INPUT LO terminals. A.
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3-22 Basic DMM Operation Model 2700 Multimeter/Switch System User’s Manual Model 7700 switching module Connections for the switching module are shown in Figure 3-9. As shown in Figure 3-9A, each of the 20 channels can be used to perform Ω2 measurements. For Ω4 measurements, a channel pair is used for each 4-wire measurement as shown in Figure 3-9B.
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Model 2700 Multimeter/Switch System User’s Manual Basic DMM Operation 3-23 Cable leakage For high resistance measurements in a high humidity environment, use Teflon™ insulated cables to minimize errors due to cable leakage. Standard resistance measurements 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 modules, it must be in the “R” (in) position. Perform the following steps to measure resistance: 1. 2. 3. 4.
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3-24 Basic DMM Operation Model 2700 Multimeter/Switch System User’s Manual Offset-compensated ohms The presence of thermal EMFs (VEMF) can adversely affect low-resistance measurement accuracy. To overcome these unwanted offset voltages, you can use offset-compensated ohms (OCOMP). Offset-compensated ohms measurements can be performed on the 100Ω, 1kΩ, and 10kΩ ranges for the Ω4 function. It cannot be done on the Ω2 function.
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Model 2700 Multimeter/Switch System User’s Manual Basic DMM Operation 3-25 Performing offset-compensated ohms measurements Offset-compensated ohms can only be performed on the Ω4 function using the 100Ω, 1kΩ, or 10kΩ range. Make sure you use 4-wire connections to the DUT (see “Connections,” page 3-8). NOTE 1. 2. 3. 4. NOTE Make sure the INPUTS switch is in the correct position. To use front panel inputs, it must be in the “F” (out) position.
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3-26 Basic DMM Operation Model 2700 Multimeter/Switch System User’s Manual Constant-current source method For the 100Ω to 1MΩ ranges, the Model 2700 uses the constant-current method to measure resistance. The Model 2700 sources a constant current (ISOUR) to the DUT and measures the voltage (VMEAS). Resistance (RDUT) is then calculated (and displayed) using the known current and measured voltage (RDUT = VMEAS/ISOUR). The constant-current method is shown in Figure 3-10.
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Model 2700 Multimeter/Switch System User’s Manual Basic DMM Operation 3-27 Ratiometric method For the 10MΩ and 100MΩ ranges, the ratiometric method is used to measure resistance. Test current for this method is generated by a 0.7µA current source (ISOUR) in parallel with a 10MΩ reference resistance (RREF) as shown in Figure 3-11. Figure 3-11 Ratiometric method to measure ohms (10MΩ and 100MΩ ranges) A) 2-wire ohms (W2) measurements (10MW and 100MW ranges) 2700 V Eq.
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3-28 Basic DMM Operation Model 2700 Multimeter/Switch System User’s Manual Since I = V/R, Eq. 1 is modified using the V/R equivalents in place of IREF and IDUT. Therefore: ISOUR = (VMEAS / RREF) + (VMEAS / RDUT) Eq. 1 is then rearranged to solve for RDUT and is shown in Eq. 2 of Figure 3-11. Keep in mind that VMEAS is measured by the Model 2700. With VMEAS, ISOUR, RREF known, the Model 2700 calculates the resistance of the DUT and displays the result. NOTE Eq.
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Model 2700 Multimeter/Switch System User’s Manual Basic DMM Operation 3-29 Open test lead detection is illustrated in Figure 3-12 for an Ω4 measurement of a 100Ω resistor using the 100Ω range. For an Ω2 measurement, sense circuity is not used. With the test leads properly connected, as shown in Figure 3-12A, 1mA is sourced through the 100Ω DUT. The 100mV drop across the DUT appears on the Input Hi terminal. Resistance is then calculated (100mV / 1mA = 100Ω) and displayed by the Model 2700.
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3-30 Basic DMM Operation Model 2700 Multimeter/Switch System User’s Manual Figure 3-12 Open ohms test lead detection A) Normal 4-wire ohms measurement Sense HI Input HI DUT 1mA 100W H/W Detection 100mV S/W Detection I-Source 100.000 W 2700 Reading (100W range) Input Lo Sense Lo 2700 S/W Detection 100mV S/W Detection 0mV B) Open input lead lead detected Sense HI Input HI DUT 100W Open Input Lead 1mA H/W Detection 6.6V S/W Detection I-Source W OVR.
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Model 2700 Multimeter/Switch System User’s Manual Basic DMM Operation 3-31 10MΩ and 100MΩ ranges – Open sense lead detection for the 10MΩ and 100MΩ detection is slightly different and is shown in Figure 3-13. Detection is performed at Sense Lo only. Sense Hi is not used. It does not need to be connected to the DUT. When the Sense Lo lead opens, the Sense Lo terminal will drift to -15mV and trip the “OVRFLOW” message.
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3-32 Basic DMM Operation Model 2700 Multimeter/Switch System User’s Manual 4-wire common-side (CSID) ohms measurements (7701 module) For normal 4-wire ohms measurements using a switching module, channels are paired to provide the switch paths for input and sense. Each tested DUT requires two input channels. For example, the 7700 module has 20 channels. With the Ω4 function selected, channel 1 is paired to channel 11, channel 2 is paired to channel 12, and so on.
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Model 2700 Multimeter/Switch System User’s Manual Basic DMM Operation 3-33 Temperature measurements The Model 2700 can measure temperature using thermocouples, thermistors, and 4-wire RTDs. When deciding which temperature sensor to use, keep in mind that the thermocouple is the most versatile, the thermistor is the most sensitive, and the 4-wire RTD is the most stable. Thermocouples For thermocouples, temperature measurement range depends on which type of thermocouple is being used.
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3-34 Basic DMM Operation Model 2700 Multimeter/Switch System User’s Manual Reference junctions A reference junction is the cold junction in a thermocouple circuit which is held at a stable, known temperature. It is at the cold junction where dissimilar wire connections must be made. As long as the temperature of the cold junction is known, the Model 2700 can factor in the reference temperature to calculate the actual temperature reading at the thermocouple.
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Model 2700 Multimeter/Switch System User’s Manual Basic DMM Operation 3-35 External reference junction For switching modules that do not have built-in sensors to measure temperature, each module can use a thermistor or 4-wire RTD to acquire the reference temperature. Connect a thermistor to channel 1 or connect a 4-wire RTD to channel 1 and its paired channel. Position the temperature transducer near the terminals for the channel(s) being used to measure temperature.
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3-36 Basic DMM Operation Model 2700 Multimeter/Switch System User’s Manual 4-wire RTDs For 4-wire RTDs, the temperature measurement range is -200°C to 630°C (0.01°C resolution). RTD types that are supported include D100, F100, PT385, and PT3916. A USER type is available to modify RTD parameters, such as the resistance at 0°C. The USER type can be enabled from the front panel, but the settings can only be changed using remote programming. The RTD has a metal construction (typically platinum).
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Model 2700 Multimeter/Switch System User’s Manual Basic DMM Operation 3-37 reference junction may be inconvenient but it will provide more accurate temperature measurements (assuming the user enters a precise reference temperature). With open thermocouple detection disabled, the Model 2700 can calculate the average temperature of two thermocouple channels using Channel Average (see Section 5 for details).
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3-38 Basic DMM Operation Model 2700 Multimeter/Switch System User’s Manual Table 3-2 Color codes — thermocouple wires T/C type J U.S.
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Model 2700 Multimeter/Switch System User’s Manual Basic DMM Operation 3-39 Thermistor connections A thermistor can be connected directly to the front panel inputs or to any of the 20 input channels of the Model 7700 switching module as shown in Figure 3-15. Figure 3-15 Thermistor connections Model 2700 Input HI Thermistor Input LO A. Front panel inputs H Model 7700 Switching Module CH 1-20 Thermistor L B.
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3-40 Basic DMM Operation Model 2700 Multimeter/Switch System User’s Manual Temperature measurement configuration The Model 2700 is configured to measure temperature from the temperature measurement configuration menu. Use the following general rules to navigate through the menu structure: • • • • • Press SHIFT and then SENSOR to enter the menu structure. Cursor position is indicated by a flashing menu item or parameter. Cursor position is controlled by the and keys.
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Model 2700 Multimeter/Switch System User’s Manual Basic DMM Operation 3-41 Table 3-3 Thermocouple temperature measurement configuration Step Menu structure Description 1 UNITS: C, F, or K Select temperature measurement units (°C, °F, or K). 2 SENS: TCOUPLE Select the thermocouple transducer. 3 TYPE: J, K, T, E, R, S, B, or N Select thermocouple type. 4 JUNC: SIM, INT, or EXT Select the SIMulated, INTernal or EXTernal reference junction*.
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3-42 Basic DMM Operation Model 2700 Multimeter/Switch System User’s Manual 4-wire RTD temperature measurement configuration The Alpha, Beta, Delta, and Ω at 0°C parameters for the five basic RTD types are provided in Table 3-5. Note that these parameters can be modified using remote programming. Table 3-5 RTD parameters Type Standard Alpha Beta Delta Ω at 0°C PT100 ITS-90 0.00385055 0.10863 1.49990 100Ω D100 ITS-90 0.003920 0.10630 1.49710 100Ω F100 ITS-90 0.003900 0.11000 1.
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Model 2700 Multimeter/Switch System User’s Manual Basic DMM Operation 3-43 Temperature measurement procedure NOTE 1. 2. 3. 4. 5. 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 modules, it must be in the “R” (in) position. If a switching channel is presently closed (displayed), press OPEN to open it. Select the temperature measurement function by pressing TEMP.
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3-44 Basic DMM Operation Model 2700 Multimeter/Switch System User’s Manual Frequency and period measurements The Model 2700 can make frequency measurements from 3Hz to 500kHz on voltage ranges of 100mV, 1V, 10V, 100V, and 750V. Period (1 / frequency) measurements can be taken from 2µs to 333ms on the same voltage ranges as the frequency. Input impedance:1MΩ || <100pF, AC coupled. The instrument uses the volts input to measure frequency. The AC voltage range can be changed with the RANGE Δ and ∇ keys.
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Model 2700 Multimeter/Switch System User’s Manual Basic DMM Operation 3-45 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. Front panel input When using the front panel input terminals, connect the test leads to the INPUT HI and LO terminals as shown in Figure 3-17.
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3-46 Basic DMM Operation Model 2700 Multimeter/Switch System User’s Manual Frequency and period measurement procedure NOTE 1. 2. 3. 4. 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 modules, it must be in the “R” (in) position. If a switching channel is presently closed (displayed), press OPEN to open it. Perform one of the following steps to select the function: • Press FREQ to perform frequency measurements.
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Model 2700 Multimeter/Switch System User’s Manual Basic DMM Operation 3-47 Continuity testing The instrument can test continuity using the 2-wire 1kΩ range. After selecting continuity, you will be prompted to enter the threshold resistance level (1 to 1000Ω). When the measured circuit is below the set threshold level, the instrument will beep and display the resistance readings. When the measured circuit is above the threshold level, the unit will stop beeping and it will display the resistance value.
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3-48 Basic DMM Operation Model 2700 Multimeter/Switch System User’s Manual Figure 3-19 Continuity connections Model 2700 Input HI Resistance Under Test Input LO A. Front panel connections Model 7700 Switching Module H CH 1-20 L Resistance Under Test Note: Source current flows from input high to input low. B. Model 7700 connections Continuity testing procedure NOTE 1. 2. 3. 4. NOTE Make sure the INPUTS switch is in the correct position.
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Model 2700 Multimeter/Switch System User’s Manual Basic DMM Operation 3-49 Remote programming for basic measurements Basic measurement commands NOTE When measurements are performed, the readings are fed to other enabled processing operations. Appendix D explains “Data flow (remote operation)” and the commands used to return the various processed readings. Commands to perform basic measurements are listed in Table 3-7.
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3-50 Basic DMM Operation Model 2700 Multimeter/Switch System User’s Manual Table 3-7 (continued) Basic measurement commands Commands1 Description Default Ref TEMP function [SENSe[1]] :TEMPerature:TRANsducer [, ] :TEMPerature:TCouple:TYPE [, ] :TEMPerature:TCouple:ODETect :TEMPerature:TCouple:RJUNction: RSELect [, ] :TEMPerature:TCouple:RJUNction: SIMulated [, ] :TEMPerature:THERmistor [, ] :TEMPerature:FRTD:TYPE [, ] :
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Model 2700 Multimeter/Switch System User’s Manual Basic DMM Operation 3-51 Table 3-7 (continued) Basic measurement commands Commands1 PERIOD function :PERiod:THReshold:VOLTage:RANGe [, ] :PERiod:APERture [, ] CONT function [SENSe[1]] :CONTinuity:THReshold SYSTem:BEEPer Set temperature measurement units UNIT:TEMPerature Trigger and retrieve readings INITiate:CONTinuous INITiate [SENSe[1]] :DATA[:LATest]? :DATA:FRESh? FETCh? READ? Description Select threshold vol
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3-52 Basic DMM Operation Model 2700 Multimeter/Switch System User’s Manual Reference a. FUNCtion [, ] Note that the parameters in the table are enclosed in single quotes (‘ ’). However, double quotes (“ ”) can instead be used. For example: FUNC ‘VOLT:AC’ = FUNC “VOLT:AC” Scan configuration — When using the command to configure a scan channel, the scan channel must first be set to the appropriate function before sending other commands to configure it.
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Model 2700 Multimeter/Switch System User’s Manual d. Basic DMM Operation 3-53 TEMPerature:TCouple:RJUNction:SIMulated [, ] The units for the simulated reference temperature depend on the present temperature measurement units as set by UNIT:TEMPerature (see Ref h). NOTE The following command can instead be used to set the simulated reference temperature: TEMPerature:RJUNction:SIMulated [, ] e.
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3-54 Basic DMM Operation Model 2700 Multimeter/Switch System User’s Manual DATA[:LATest]? DATA:FRESh? These commands do not trigger a reading. They simply return the last reading string. The reading reflects what is applied to the input. While the instrument is performing measurements, you can use these commands to return the last reading. If the instrument is not performing measurements, DATA[:LATest]? will keep returning the same reading string.
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Model 2700 Multimeter/Switch System User’s Manual Basic DMM Operation 3-55 Basic measurement programming examples Example #1 — continuous triggering The following command sequence places the Model 2700 in a continuous trigger mode to measure ACV. Whenever DATA? is sent, the last measured reading will be sent to the computer when the Model 2700 is addressed to talk. NOTE The following example can be run from the KE2700 Instrument Driver using the example named “CTMMV” in Table H-1 of Appendix H.
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3-56 Basic DMM Operation Model 2700 Multimeter/Switch System User’s Manual Example #4 — Scan configuration (Model 7700) The following commands configure scan channels 101, 102, and 121 of a Model 7700 installed in slot 1. When channel 101 is scanned, DCV will be selected. When channel 102 is scanned, Ω2 will be selected. When channel 121 is scanned, DCI will be selected.
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Model 2700 Multimeter/Switch System User’s Manual Basic DMM Operation 3-57 Where appropriate Since this query does not trigger a reading, and can give duplicate results, there are not many cases where this command should be used. The “:DATA:FRESh?” query (see page 3-47) is often a better choice.
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3-58 Basic DMM Operation Model 2700 Multimeter/Switch System User’s Manual :MEASure[:]? What it does This query will reconfigure the instrument to the function specified in the query, set the trigger source for immediate, set the trigger count to 1, and configure the measurement parameters to *RST defaults. It will then trigger a single reading, and return the result.
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Model 2700 Multimeter/Switch System User’s Manual Basic DMM Operation 3-59 [:SENSe[1]]:DATA[:LATest]? What it does This query will return the last reading the instrument had, regardless of what may have invalidated that reading, such as changing ranges or functions. Limitations This query is fully capable of returning meaningless, old data.
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3-60 Basic DMM Operation Model 2700 Multimeter/Switch System User’s Manual 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 :INITiate *TRG -or- GET // Triggers reading (GET is a GPIB general bus command).
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4 Range, Digits, Rate, Bandwidth, and Filter • Range — Provides details on measurement range selection. Includes the commands for remote programming. • Digits — Provides details on selecting display resolution. Includes the commands for remote programming. • Rate and bandwidth — Provides details on integration rate and bandwidth (for AC measurements). Includes the commands for remote programming. • Filter — Provides details on filtering. Includes the commands for remote programming.
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4-2 Range, Digits, Rate, Bandwidth, and Filter Model 2700 Multimeter/Switch System User’s Manual Range The range setting is “remembered” by each measurement function. When you select a function, the instrument will return to the last range setting for that function. Measurement ranges and maximum readings The selected range affects both accuracy of the measurement as well as the maximum level that can be measured.
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Model 2700 Multimeter/Switch System User’s Manual Range, Digits, Rate, Bandwidth, and Filter 4-3 Manual ranging To change range, press the RANGE Δ or ∇ key. The instrument changes one range per key press. The selected range is displayed for one second. Note that the manual range keys have no effect on temperature (TEMP). If the instrument displays the “OVERFLOW” message on a particular range, select a higher range until an on-range reading is displayed.
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4-4 Range, Digits, Rate, Bandwidth, and Filter Model 2700 Multimeter/Switch System User’s Manual Remote programming — range Range commands The commands to set range are listed in Table 4-2. Additional information on these commands follow the table. NOTE Query commands and some optional command words are not included in Table 4-2. All commands for the SENSe subsystem are provided in Table 15-5. Table 4-2 Range commands Commands1, 2 Description [SENSe[1]] Optional root command.
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Model 2700 Multimeter/Switch System User’s Manual Range, Digits, Rate, Bandwidth, and Filter 4-5 Manual ranging The range is selected by specifying the expected reading as an absolute value using the parameter for the appropriate :RANGe command. The Model 2700 will then go to the most sensitive range for that expected reading. For example, if you expect a reading of approximately 3V, let the parameter () equal 3 to select the 10V range.
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4-6 Range, Digits, Rate, Bandwidth, and Filter Model 2700 Multimeter/Switch System User’s Manual Scanning When a simple scan is configured, the present digits setting will apply to all channels in the scan. When an advanced scan is configured, each channel can have its own unique digits setting. Details to configure and run a scan are provided in Section 7. For remote programming, the parameter is used to configure channels for a scan.
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Model 2700 Multimeter/Switch System User’s Manual Range, Digits, Rate, Bandwidth, and Filter 4-7 Setting digits Even though the parameters for the DIGits command are expressed as integers (4 to 7), you can specify resolution using a real number. For example, to select 3Hdigit resolution, let = 3.5. Internally the instrument rounds the entered parameter value to the nearest integer. As implied by the commands in Table 4-3, each mainframe input function can have its own unique digits setting.
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4-8 Range, Digits, Rate, Bandwidth, and Filter Model 2700 Multimeter/Switch System User’s Manual Rate and bandwidth Rate The RATE key sets the integration time (measurement speed) of the A/D converter, the period of time the input signal is measured (also known as aperture). The integration time affects the amount of reading noise, as well as the ultimate reading rate of the instrument.
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Model 2700 Multimeter/Switch System User’s Manual Range, Digits, Rate, Bandwidth, and Filter 4-9 The front panel RATE settings for all but the AC functions are explained as follow: • FAST sets integration time to 0.1 PLC. Use FAST if speed is of primary importance (at the expense of increased reading noise and fewer usable digits). MEDium sets integration time to 1 PLC. Use MEDium when a compromise between noise performance and speed is acceptable. SLOW sets integration time to 5 PLC.
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4-10 Range, Digits, Rate, Bandwidth, and Filter Model 2700 Multimeter/Switch System User’s Manual Bandwidth Bandwidth specifies the lowest frequency of interest for AC measurements. The RATE setting determines the bandwidth setting: • • • SLOW — 3Hz to 300kHz MEDium — 30Hz to 300kHz FAST — 300Hz to 300kHz When the Slow bandwidth (3Hz to 300kHz) is chosen, the signal goes through an analog RMS converter.
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Model 2700 Multimeter/Switch System User’s Manual Range, Digits, Rate, Bandwidth, and Filter 4-11 Table 4-5 Rate and bandwidth commands Commands 1, 7 Description Integration rate commands [SENSe[1]] Optional root command. :VOLTage[:DC]:NPLCycles [, ] Set rate for DCV in PLCs; = 0.01 to x2. :VOLTage[:DC]:APERture [, ] Set rate for DCV in secs; = x to 13. :VOLTage:AC:NPLCycles [, ] Set rate for ACV in PLCs; = 0.01 to xx2,5.
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4-12 Range, Digits, Rate, Bandwidth, and Filter Model 2700 Multimeter/Switch System User’s Manual Aperture Aperture is a different way to specify the integration rate. As previously explained, 1 PLC sets the integration rate to 16.67msec (assuming 60Hz line power). You can instead use an APERture command as follows to set the same integration rate: :APERture 16.
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Model 2700 Multimeter/Switch System User’s Manual Range, Digits, Rate, Bandwidth, and Filter 4-13 Rate and bandwidth programming examples NOTE The following examples can be run from the KE2700 Instrument Driver using the example named “RateBandwidth” in Table H-1 of Appendix H. Example #1 — The following command sequence sets ACV rate to 5 PLC. In order to set rate for an AC function, bandwidth must first be set to 300: VOLT:AC:DET:BAND 300 VOLT:AC:NPLC 5 NOTE ' Set ACV bandwidth to 300.
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4-14 Range, Digits, Rate, Bandwidth, and Filter Model 2700 Multimeter/Switch System User’s Manual Filter type There are two digital filter types: moving and repeating. The moving average filter uses a first-in first-out stack, where the newest reading conversion replaces the oldest. An average of the stacked reading conversions yields a filtered reading. After the specified number of reading conversions (“Filter count”) fill the stack, the moving filter gives a new reading for every new conversion.
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Model 2700 Multimeter/Switch System User’s Manual Range, Digits, Rate, Bandwidth, and Filter 4-15 Figure 4-2 Moving and repeating filters A. Type - Moving Average, Readings = 10 Conversion Conversion #10 #9 #8 #7 #6 #5 #4 #3 #2 #1 Conversion Average Reading #1 Conversion #11 #10 #9 #8 #7 #6 #5 #4 #3 #2 Conversion Average Reading #2 Conversion #12 #11 #10 #9 #8 #7 #6 #5 #4 #3 Average Reading #3 #30 #29 #28 #27 #26 #25 #24 #23 #22 #21 Average Reading #3 B.
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4-16 Range, Digits, Rate, Bandwidth, and Filter Model 2700 Multimeter/Switch System User’s Manual Filter window The digital filter uses a “noise” window to control filter threshold. As long as the input signal remains within the selected window, A/D conversions continue to be placed in the stack. If the signal changes to a value outside the window, the filter resets and the filter starts processing again starting with a new initial conversion value from the A/D converter.
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Model 2700 Multimeter/Switch System User’s Manual Range, Digits, Rate, Bandwidth, and Filter 4-17 Figure 4-3 Filter window +1% of range Voltage B Windows Violation -1% of range +1% of range A -1% of range Integration Time t1 t2 t3 t4 t5 t6 t7 t8 t9 t10 t11 A1 A1 A1 A1 A1 A2 A1 A1 A1 A1 A3 A2 A1 A1 A1 A4 A3 A2 A1 A1 A5 A4 A3 A2 A1 A6 A5 A4 A3 A2 B1 A5 A4 A3 A2 B2 B1 A5 A4 A3 B3 B2 B1 A5 A4 B4 B3 B2 B1 A5 B5 B4 B3 B2 B1 Rdg #1 Rdg #2 Rdg #3 Rdg #4 Rdg #5 Rdg #6 Rdg #7 Rdg
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4-18 Range, Digits, Rate, Bandwidth, and Filter Model 2700 Multimeter/Switch System User’s Manual Filter control and configuration The FILTER key toggles the state of the Filter. When the Filter is enabled, the FILT annunciator is on. The FILT annunciator will flash when the filter is not settled. When disabled, the FILT annunciator is off. The filter can be configured while it is enabled or disabled. The filter is configured from the filter configuration menu (Figure 4-4).
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Model 2700 Multimeter/Switch System User’s Manual Range, Digits, Rate, Bandwidth, and Filter 4-19 Scanning The moving filter cannot be used when scanning. A scan channel cannot be configured to use the moving filter. Also, the filter window is not used when scanning. When a simple scan is configured, the present filter count and state will apply to all channels in the scan.
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4-20 Range, Digits, Rate, Bandwidth, and Filter Model 2700 Multimeter/Switch System User’s Manual Remote programming — filter Filter commands The filter commands are listed in Table 4-6. Additional information on these commands follow the table. NOTE Query commands are not included in Table 4-6. All commands for the SENSe subsystem are provided in Table 15-5.
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Model 2700 Multimeter/Switch System User’s Manual Range, Digits, Rate, Bandwidth, and Filter 4-21 Table 4-6 (continued) Filter commands Commands1, 4 Ω2 filter commands [SENSe[1]] :RESistance:AVERage:TCONtrol :RESistance:AVERage:WINDow :RESistance:AVERage:COUNt [, clist] :RESistance:AVERage:STATe [, clist] Ω4 filter commands [SENSe[1]] :FRESistance:AVERage:TCONtrol :FRESistance:AVERage:WINDow :FRESistance:AVERage:COUNt [, clist] :FRESistance:AVERage:STATe [, clist
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4-22 Range, Digits, Rate, Bandwidth, and Filter Model 2700 Multimeter/Switch System User’s Manual Filter programming examples NOTE The following example can be run from the KE2700 Instrument Driver using the example named “MAFilter” in Table H-1 of Appendix H. Example #1 — The following command sequence configures filtering for the DCI function: CURR:TCON MOV CURR:AVER:WIND 0.01 CURR:AVER:COUN 10 CURR:AVER ON NOTE ' ' ' ' Select the moving filter. Set filter window to 0.01%.
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5 Relative, Math, Ratio, Channel Average, and dB • Relative — Explains how to null an offset or establish a baseline value. Includes the commands for remote programming. • Math — Covers the three basic math operations: mX+b, percent, and reciprocal (1/X). Includes the commands for remote programming. • Ratio and channel average — Explains how to use these calculations to display the ratio or average of two switching channels.
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5-2 Rel, Math, Ratio, Channel Average, dB Model 2700 Multimeter/Switch System User’s Manual Relative The rel (relative) function can be used to null offsets or subtract a baseline reading from present and future readings. When rel is enabled, the instrument uses the present reading as a relative value. Subsequent readings will be the difference between the actual input value and the rel value. You can define a rel value for each function.
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Model 2700 Multimeter/Switch System User’s Manual 4. 5. Rel, Math, Ratio, Channel Average, dB 5-3 Press the REL key to set the rel value. The display will zero and the REL annunciator will turn on. Apply the signal to be measured. Pressing REL a second time disables rel. You can input a rel value manually using the mX+b function. Set M for 1 and B for any value you want. The mX+b function is covered in this section (see “Math,” page 5-8).
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5-4 Rel, Math, Ratio, Channel Average, dB Model 2700 Multimeter/Switch System User’s Manual Remote programming — rel Rel commands The rel commands to set range are listed in Table 5-1. Additional information on these commands follow the table. NOTE Query commands are not included in Table 5-1. All commands for the SENSe subsystem are provided in Table 15-5.
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Model 2700 Multimeter/Switch System User’s Manual Rel, Math, Ratio, Channel Average, dB 5-5 Table 5-1 (continued) Rel commands Commands1 Rel commands for Ω2 [SENSe[1]] :RESistance:REFerence [, ] :RESistance:REFerence:STATe [, ] :RESistance:REFerence:ACQuire [, ] Description Optional root command. Specify rel value; = 0 to 120e6 (Ω). Enable/disable rel; = ON or OFF. Use input signal as rel value. Rel commands for Ω4 [SENSe[1]] Optional root command.
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5-6 Rel, Math, Ratio, Channel Average, dB Model 2700 Multimeter/Switch System User’s Manual “Pressing REL” using rel commands When the front panel REL key is pressed, the displayed reading is used as the rel value. Subsequent readings are then the result of the actual input value and the rel value. The :REFerence:ACQuire and :REFerence:STATe ON commands (in that order) can be used to “press” the REL key.
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Model 2700 Multimeter/Switch System User’s Manual Rel, Math, Ratio, Channel Average, dB 5-7 Rel programming examples Example #1 — The following command sequence zeroes the display for DCV. NOTE The following example can be run from the KE2700 Instrument Driver using the example named “Relative1” in Table H-1 of Appendix H. FUNC 'VOLT' VOLT:REF:ACQ VOLT:REF:STAT ON ' Select DCV. ' Use input level as rel value for DCV. ' Enable rel.
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5-8 Rel, Math, Ratio, Channel Average, dB Model 2700 Multimeter/Switch System User’s Manual Math The Model 2700 has three built-in math calculations that are accessed from the MATH menu: mX+b, percent, and reciprocal (1/X). Figure 5-1 shows the MATH menu tree. Note that the settings shown in the menu tree are the factory defaults. NOTE The various instrument operations, including Math, are performed on the input signal in a sequential manner. See “Signal processing sequence,” page D-2, for details.
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Model 2700 Multimeter/Switch System User’s Manual Rel, Math, Ratio, Channel Average, dB 5-9 mX+b This math operation lets you manipulate normal display readings (X) mathematically according to the following calculation. Y = mX + b where: X is the normal display reading. m and b are the user-entered constants for scale factor and offset. Y is the displayed result. NOTE When using Rel, the rel’ed reading of the input signal is used by the mX+b calculation. mX+b configuration 1. 2.
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5-10 Rel, Math, Ratio, Channel Average, dB Model 2700 Multimeter/Switch System User’s Manual mX+b rel The mX+b function can be used to manually establish a rel value. To do this, set the scale factor (m) to 1 and set the offset (b) to the rel value. Each subsequent reading will be the difference between the actual input and the rel value (offset). Percent This math function determines percent deviation from a specified reference value.
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Model 2700 Multimeter/Switch System User’s Manual Rel, Math, Ratio, Channel Average, dB 5-11 Reciprocal (1/X) The reciprocal of a reading is displayed when the reciprocal (1/X) math function is enabled: Reciprocal = 1/X where: X is the normal input reading The displayed units designator for reciprocal readings is “R.” This units designator cannot be changed. Example — Assume the normal displayed reading is 2.5Ω. The reciprocal of resistance is conductance.
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5-12 Rel, Math, Ratio, Channel Average, dB Model 2700 Multimeter/Switch System User’s Manual Basic operation NOTE 1. 2. 3. NOTE 4. If using switching module inputs, make sure the front panel INPUTS switch is set to the REAR position (in). If using the front panel inputs, the switch must be in the FRONT position (out). Configure and enable the mX+b, percent, or reciprocal (1/X) math function as previously explained. Select the desired measurement function.
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Model 2700 Multimeter/Switch System User’s Manual Rel, Math, Ratio, Channel Average, dB 5-13 Remote programming — math Math commands NOTE When measurements are performed, the readings are fed to other enabled processing operations, including Math. Appendix D explains “Data flow (remote operation),” page D-7, and the commands used to return Math results. The commands to perform math calculations are listed in Table 5-2. Details on these commands follow the table.
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5-14 Rel, Math, Ratio, Channel Average, dB Model 2700 Multimeter/Switch System User’s Manual Setting mX+b units The parameter for CALCulate:KMATh:MUNits must be one character enclosed in single or double quotes. It can be any letter of the alphabet, the degrees symbol (°) or the ohms symbol (Ω).
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Model 2700 Multimeter/Switch System User’s Manual Rel, Math, Ratio, Channel Average, dB 5-15 Math programming examples Example #1 — The following command sequence performs the mX+b calculation for channels 101 and 102 of the Model 7700. Keep in mind that after CALC:DATA? is sent, the Model 2700 has to be addressed to talk to send the math result to the computer. NOTE The following example can be run from the KE2700 Instrument Driver using the example named “Linear” in Table H-1 of Appendix H.
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5-16 Rel, Math, Ratio, Channel Average, dB Model 2700 Multimeter/Switch System User’s Manual Ratio and channel average With a switching module installed in the Model 2700, the ratio or average of two channels can be calculated and displayed. The ratio calculation can be done on the DCV function, and the channel average calculation can be done on the DCV and TEMP (thermocouples only) functions.
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Model 2700 Multimeter/Switch System User’s Manual Rel, Math, Ratio, Channel Average, dB 5-17 Basic operation NOTE 1. 2. 3. 4. 5. NOTE Make sure the INPUTS switch is set to the REAR position (in). Select and configure (range, filter, rel, etc.) a valid measurement function. For ratio, the only valid function is DCV. For channel average, the only valid functions are DCV and TEMP (TCs only). Use the or key to select (close) a primary channel (101 through 110 for the Model 7700).
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5-18 Rel, Math, Ratio, Channel Average, dB Model 2700 Multimeter/Switch System User’s Manual Scanning Ratio and channel average can be used in an advanced scan. The 2-channel scan for the calculation is performed for every primary channel that is scanned. For example, assume the Model 7700 is installed in slot 1 and is configured to perform the ratio calculation for 10 channels. When channel 101 is scanned, measurements are performed on channels 101 and on its paired channel (111).
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Model 2700 Multimeter/Switch System User’s Manual Rel, Math, Ratio, Channel Average, dB 5-19 Remote programming — ratio and channel average Ratio and channel average commands The ratio and channel average are listed in Table 5-3. Details on these commands follow the table. NOTE Queries are not included in Table 5-3. All the math commands are provided in Table 15-5. Table 5-3 Ratio and channel average commands Commands* Description [SENSe[1]] Optional root command.
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5-20 Rel, Math, Ratio, Channel Average, dB Model 2700 Multimeter/Switch System User’s Manual 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 Model 2700 must be addressed to talk to return the result of the calculation. NOTE The following example can be run from the KE2700 Instrument Driver using the example named “Ratio1” in Table H-1 of Appendix H.
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Model 2700 Multimeter/Switch System User’s Manual Rel, Math, Ratio, Channel Average, dB 5-21 dB Expressing DC or AC voltage in dB makes it possible to compress a large range of measurements into a much smaller scope. The relationship between dB and voltage is defined by the following equation: V IN dB = 20log ------------V REF where: VIN is the DC or AC input signal. VREF is the specified voltage reference level. The instrument will read 0dB when the reference voltage level is applied to the input.
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5-22 Rel, Math, Ratio, Channel Average, dB Model 2700 Multimeter/Switch System User’s Manual Remote programming — dB dB commands The dB commands are listed in Table 5-4. Details on these commands follow the table. NOTE Queries are not included in Table 5-4. All the dB commands are provided in Table 15-10.
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Model 2700 Multimeter/Switch System User’s Manual Rel, Math, Ratio, Channel Average, dB 5-23 Programming examples — dB Example #1 — The following command sequence configures the Model 2700 to perform DCV dB measurements. A 1V input will be measured as 0dB. NOTE The following example can be run from the KE2700 Instrument Driver using the example named “VoltdB1” in Table H-1 of Appendix H. FUNC 'VOLT' UNIT:VOLT DB UNIT:VOLT:DB:REF 1V ' Select DCV function. ' Select DCV dB. ' Set dB reference to 1V.
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5-24 Rel, Math, Ratio, Channel Average, dB Model 2700 Multimeter/Switch System User’s Manual
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6 Buffer • Buffer overview — Summarizes basic buffer (data store) capabilities. • Front panel buffer — Explains how to store and recall readings, and discusses the various statistics available on buffer data including minimum and maximum values, average (mean), standard deviation, and peak-to-peak values. • Remote programming buffer — Summarizes the commands to control the data store and provides a programming example.
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6-2 Buffer Model 2700 Multimeter/Switch System User’s Manual Buffer overview The Model 2700 has a data store (buffer) to store from 2 to 55,000 readings. The instrument stores the readings that are displayed during the storage process. Each timestamped reading includes the buffer location number and a timestamp. The data store also provides statistical data on the measured readings stored in the buffer. These include minimum, maximum, average, peak-to-peak, and standard deviation.
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Model 2700 Multimeter/Switch System User’s Manual Buffer 6-3 With buffer auto clear disabled, the only two valid buffer size values are 55000 and 000000. Buffer size 000000 clears the buffer. Entering any other buffer size value resets the buffer size to 55000. NOTE If the buffer is empty when the Model 2700 is turned off, buffer auto clear will enable when it is turned back on. If the buffer is not empty, the instrument will power up to the last auto clear setting.
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6-4 Buffer Model 2700 Multimeter/Switch System User’s Manual Timestamps Each stored reading is referenced to either a real-time clock timestamp or to a relative timestamp. Relative timestamp — With relative selected, there are two timestamp types for each reading: absolute and delta. The absolute timestamp (S) references each stored reading to zero seconds. Therefore, the first reading in the buffer has an absolute timestamp of zero seconds.
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Model 2700 Multimeter/Switch System User’s Manual Buffer 6-5 Configuring timestamp Setting time and date For the real-time clock, the time and date is set at the factory. However, you can check and correct the time and date as follows: Perform the following steps to set the time: 1. 2. 3. Press SHIFT and then SETUP. Use the Δ and ∇ keys to display SET TIME and press ENTER. The displayed clock will be running in the hour/minute/second AM/PM format.
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6-6 Buffer Model 2700 Multimeter/Switch System User’s Manual Storing readings Perform the following steps to store readings: 1. 2. 3. NOTE 4. 5. NOTE Set up the Model 2700 for the desired configuration. Press the STORE key. Use the , , Δ, and ∇ keys to specify the number of readings to store in the buffer (2 to 55000). Pressing the AUTO key sets the readings count to 000000. With buffer auto clear disabled, the only valid buffer size values are 55000 and 000000 (which clears the buffer).
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Model 2700 Multimeter/Switch System User’s Manual Buffer 6-7 Figure 6-1 Recalling buffer data — relative timestamp RANGE RANGE RDG RDG RDG RDG RDG RDG RDG RDG RDG RDG STD Average Peak-to-Peak Min Max NO. NO. NO. NO. NO. NO. NO. NO. NO. NO.
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6-8 Buffer Model 2700 Multimeter/Switch System User’s Manual Buffer statistics Minimum and maximum This mode displays the minimum and maximum readings stored in the buffer. The buffer location number and timestamp are also provided for these readings. Peak-to-peak This mode displays the peak-to-peak reading (peak-to-peak = Maximum - Minimum). Average The average mode displays the mean (average) of all measured readings stored in the buffer.
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Model 2700 Multimeter/Switch System User’s Manual Buffer 6-9 Remote programming — buffer 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 readings in the buffer that were stored in that manner, you cannot use the INIT or READ? command if sample count is >1 (error -225, out of memory). NOTE The measurement event register can be read to check when the buffer becomes G, H, I, or full.
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6-10 Buffer Model 2700 Multimeter/Switch System User’s Manual Table 6-1 (continued) Buffer commands Command TRACe:FEED:CONTrol TRACe:DATA? TRACe:DATA:SELected? , TRACe:NEXT? TRACe:NOTify FORMat:ELEMents CALCulate2:FORMat CALCulate2:STATe CALCulate2:IMMediate CALCulate2:IMMediate? CALCulate2:DATA? Description Set buffer control; = NEVer, NEXT, or ALWays. Read all readings in the buffer.
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Model 2700 Multimeter/Switch System User’s Manual c. SYSTem:TSTamp:TYPE RELative | RTClock SYSTem:TSTamp:TYPE? TRACe:TSTamp:TYPE? Buffer 6-11 Select timestamp Query timestamp type; next storage Query timestamp type; readings in buffer SYSTem:TSTamp:TYPE — Use to select the relative timestamp or the real-time timestamp. Note that changing the timestamp will clear the buffer if a storage is in process. If no storage is in process, changing the timestamp will not clear the buffer.
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6-12 Buffer Model 2700 Multimeter/Switch System User’s Manual g. TRACe:TSTamp:FORMat ABSolute | DELta Select timestamp format For front panel operation, both timestamp formats (absolute and delta) can be recalled. For remote programming, you can only use one timestamp at a time. NOTE Changing the timestamp format clears the buffer. The timestamp will only be included with a returned buffer reading if it is specified as a data element (see FORMat:ELEMents). h.
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Model 2700 Multimeter/Switch System User’s Manual Buffer TRACe:DATA:SELected? , TRACe:NEXT? j. 6-13 Specify readings to return Query location of last buffer reading Use the TRACe:DATA:SELected? command to specify which stored readings to return. The parameter specifies the first stored reading to return. Note that the first stored reading in the buffer is #0. The parameter specifies the number of readings to return.
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6-14 Buffer Model 2700 Multimeter/Switch System User’s Manual l. FORMat:ELEMents Select elements for TRACe:DATA? = READing, CHANnel, UNITs, RNUMber, TSTamp The data returned by TRACe:DATA? can include from one to all five data elements shown in the above item list. For example, if you want the units and reading number included with the reading, you would send this command: FORMat:ELEMents READing, UNITs, RNUMber. Only the elements defined by the list are used.
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Model 2700 Multimeter/Switch System User’s Manual Buffer m.
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6-16 Buffer Model 2700 Multimeter/Switch System User’s Manual
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7 Scanning • Scanning fundamentals — Explains channel assignments (slot/channel programming format), the difference between sequential and non-sequential scans, and the basic scan process. Block diagrams (known as trigger models) are provided to help explain the STEP and SCAN operations. • Scan configuration — Provides the step-by-step procedures to configure a simple scan or an advanced scan. Covers other scan options, including delay, monitor, auto configuration, saving setups, and auto scan.
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7-2 Scanning Model 2700 Multimeter/Switch System User’s Manual Scanning fundamentals The Model 2700 can scan the channels of up to five installed Keithley switching modules. Each scan channel can have its own unique setup. Aspects of operation that can be uniquely set for each channel include function, range, rate, AC bandwidth, rel, filter, digits, math, Ω offset compensation, TEMP transducers, limits, channel average, channel ratio, and volts dB.
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Model 2700 Multimeter/Switch System User’s Manual Scanning 7-3 Channel assignments A switching module has a certain number of channels. For example, the Model 7700 switching module has 22 channels (1 through 22). When you encounter a 1 or 2-digit channel number in this manual, the switching module channel is the point of discussion. A switching module can be installed in one of two slots of the mainframe.
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7-4 Scanning Model 2700 Multimeter/Switch System User’s Manual Scan process Basic scan — For functions that use 2-wire measurements, the basic scan process is to (1) open any closed channel, (2) close a channel, and then (3) perform the measurement. This 3-step process is repeated for each channel in the scan. The last scanned channel opens. Channel pair scan — For the functions that use 4-wire measurements (Ω4 and 4-wire RTD TEMP), the scan process uses paired channels.
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Model 2700 Multimeter/Switch System User’s Manual NOTE Scanning 7-5 The trigger model in Figure 7-2 also applies for bus operation. See “Remote programming — scanning,” page 7-26, for differences between front panel and remote scanning. For the following discussion, refer to Figure 7-1 for STEP operation, and Figure 7-2 for SCAN operation.
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7-6 Scanning Model 2700 Multimeter/Switch System User’s Manual Figure 7-2 Trigger model with SCAN function Enable Scan Close First Chan in List No Yes Control Source Immediate External Timer Manual* Bus* Another Scan? Trigger Counter Event Detection Timer Enabled ? No Output Trigger Yes Timer Bypass No Timer > Delay ? Yes Delay (Auto or Manual) Yes Another Reading ? Timer Open Last Chan Close Next Chan in List Ratio/Chan Average Delay Device Action Measurement Process *Remote programming
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Model 2700 Multimeter/Switch System User’s Manual Scanning 7-7 STEP operation overview — When the STEP key is pressed, the Model 2700 leaves the idle state, closes the first channel, and waits for the programmed trigger event. After the trigger is detected, the instrument may be subjected to one or more delays before performing the measurement.
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7-8 Scanning Model 2700 Multimeter/Switch System User’s Manual Immediate control source With immediate triggering, event detection is immediate allowing channels to be scanned. Timer control source With the timer source enabled (selected), event detection is immediately satisfied. On the initial pass through the loop, the Timer Bypass is enabled allowing operation to bypass the Timer and continue to the Delay block. On each subsequent pass through the loop, the Timer Bypass is disabled.
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Model 2700 Multimeter/Switch System User’s Manual Scanning 7-9 The auto delay period cannot be adjusted by the user. It is a fixed delay for the selected function and range (Table 8-1). NOTE When scanning, the auto delay times in Table 8-1 are valid for all control sources (Immediate, External, Timer, Manual, or Bus). With manual delay selected, the user can set the delay period from 0 seconds to 99 hours, 99 minutes, 99.999 seconds.
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7-10 Scanning Model 2700 Multimeter/Switch System User’s Manual SCAN operation — When a scan is started, one or more complete scans will be performed. The number of channels in the scan list determines the number of channels for each scan. The reading count determines the number of scans to perform and is best explained by an example. Assume there are 10 channels in the scan list. If you set the reading count to 10 or less, one scan of the 10 channels will be performed.
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Model 2700 Multimeter/Switch System User’s Manual Scanning 7-11 Figure 7-3 Scan configuration flowchart SHIFT CONFIG Simple Advanced Min Chan Setup Max Chan Imm Scan? Timer? Timer? Rdg Cnt Rdg Cnt NOTE Reset The instrument is always configured to run a scan. On power-up, each available channel uses the power-on default setup. For example, for factory power-on default settings, and two Model 7700s installed, the instrument will scan channels 101 through 220 when the scan is run.
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7-12 Scanning Model 2700 Multimeter/Switch System User’s Manual Hold — Reading hold cannot be used with scanning. Do not set up a scan channel to use hold and do not run a scan with hold enabled. NOTE When in the scan setup menu, use the edit keys ( , , Δ, and ∇ ) to make selections and set values. Displayed selections and settings are entered by pressing the ENTER key. Saving the configured scan The configured scan can be saved in a user-saved setup (SAV0, SAV1, SAV2, or SAV3).
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Model 2700 Multimeter/Switch System User’s Manual Scanning 7-13 Scan reset From the scan configuration menu, you can reset the scan configuration to the default setup for a simple scan. For the Model 7700 switching module, channels 21 and 22 are turned off (not used), and channels 1 through 20 are configured as follows: Function - DCV Range - Auto Rate - Slow All other multimeter features and functions are disabled.
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7-14 Scanning Model 2700 Multimeter/Switch System User’s Manual 7. 8. If you enabled the timer, set the timer interval using the hour/minute/second format. The timer can be set from 0.001 sec (00H:00M:00.001S) to 99 hrs, 99 min, 99.999 sec (99H:99M:99.999S). Note that pressing the AUTO key sets the timer to 0.001 sec. With the desired interval displayed, press ENTER. The displayed reading count (RDG CNT) sets the number of channels to scan (STEP) or the number of scans to run (SCAN).
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Model 2700 Multimeter/Switch System User’s Manual Scanning 7-15 Advanced scan setup notes 1. 2. 3. 4. The CHAN annunciator is on while in the scan setup menu. For some channel-specific setups, you have to configure them from a menu. For example, to set up and enable mX+B, you have to use MATH menu. While in that menu, the CHAN annunciator will flash to indicate that you are editing the mX+b math setup for that channel in the scan list.
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7-16 Scanning Model 2700 Multimeter/Switch System User’s Manual Advanced scan setup procedure Step 1: Select the advanced scan configuration menu 1. 2. Press SHIFT and then CONFIG to access the scan setup menu. Press the Δ or ∇ key to display INT: ADVANCED and press ENTER. Step 2: Edit scan channels 1. Use the or key to select channel 101: SETUP NOTE 2. NOTE 3. 4. 5. V:101 (factory default) The CLOSE key can instead be used to select a scan channel to be edited.
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Model 2700 Multimeter/Switch System User’s Manual Scanning 7-17 Step 3: Enable immediate scan The present state of immediate scan (IMM SCAN) is displayed; Y (yes, which is the factory and *RST default) or N (no). With immediate scan enabled, the scan will start when you press the STEP or SCAN key. Use the Δ or ∇ key to display IMM SCAN: Y, and press ENTER. NOTE Disable immediate scan (IMM SCAN: N) when you wish to use a monitored reading limit to trigger the start of the scan.
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7-18 Scanning Model 2700 Multimeter/Switch System User’s Manual Setting delay As shown in Figure 7-1 and Figure 7-2, a delay (auto or manual) can be set by the user. With auto delay selected, the delay period depends on function and range (Table 8-1). With manual delay selected, the delay period can be set from 0 secs to 99 hrs, 99 mins, 99.999 secs. Perform the following steps to set auto or manual delay: 1. 2. 3. NOTE 4.
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Model 2700 Multimeter/Switch System User’s Manual Scanning 7-19 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, the scan is triggered to start. The detailed procedure to perform a monitor scan is provided in “Scan operation — Monitor scan,” page 7-36.” NOTE An overflow reading (“OVRFLW” message displayed) is interpreted by the Model 2700 as a positive reading, even if the input signal is negative.
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7-20 Scanning Model 2700 Multimeter/Switch System User’s Manual Auto channel configuration Auto channel configuration allows you to recall scan list setups. With auto channel configuration enabled, a closed channel assumes the scan list setup. With this feature, you can inspect the channel setups of the scan, or manually scan channels. When a scan channel is disabled (not in scan list), it cannot be closed with auto channel configuration enabled.
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Model 2700 Multimeter/Switch System User’s Manual Scanning 7-21 Saving setup Up to four instrument setups can be saved in memory using the SHIFT > SAVE menu (SAV0, SAV1, SAV2, or SAV3). 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 When auto scan is enabled, the scan operation is saved in memory.
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7-22 Scanning Model 2700 Multimeter/Switch System User’s Manual Scan operation A basic scan is controlled solely by the STEP and SCAN keys. When one of these keys is pressed, the STEP or SCAN operation will be performed. For the manual/external trigger scan, the TRIG key or triggers received from another instrument starts the STEP or SCAN operation. For the monitor scan, a channel monitors readings. When a set reading limit is reached, STEP or SCAN will start.
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Model 2700 Multimeter/Switch System User’s Manual Scanning 7-23 Manual/external trigger scan The only difference between a manual/external trigger scan and the basic scan is control. The basic scan runs as soon as the STEP or SCAN key is pressed. The manual/external trigger scan is controlled by the front panel TRIG key or by triggers received from another instrument.
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7-24 Scanning Model 2700 Multimeter/Switch System User’s Manual Monitor scan (analog trigger) A channel can be assigned as a monitor channel. When the monitor channel detects that a reading limit has been reached, the scan will be triggered to start. There are four reading limits that can be used to trigger the start of the scan: low limit 1 (LLIM1), high limit 1 (HLIM1), low limit 2 (LLIM2), and high limit 2 (HLIM2).
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Model 2700 Multimeter/Switch System User’s Manual 2. 3. NOTE Scanning 7-25 Press the Δ or ∇ key to display IMM SCAN: N and press ENTER. a. Press the Δ or ∇ key to enable or disable low limit 1 (LLIM1 SCAN:N/Y), and press ENTER. b. Press the Δ or ∇ key to enable or disable high limit 1 (HLIM1 SCAN:N/Y), and press ENTER. c. Press the Δ or ∇ key to enable or disable low limit 2 (LLIM2 SCAN:N/Y), and press ENTER. d. Press the Δ or ∇ key to enable or disable high limit 2 (HLIM2 SCAN:N/Y), and press ENTER.
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7-26 Scanning Model 2700 Multimeter/Switch System User’s Manual Remote programming — scanning NOTE Scanning examples (remote programming and front panel operation) are provided at the end of this section. Trigger model The trigger model for bus operation is shown in Figure 7-2. Bus operation is similar to front panel SCAN operation, with the following significant differences: Idle — The instrument goes into the idle state (measurements halted) after the last scan channel is measured.
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Model 2700 Multimeter/Switch System User’s Manual Scanning 7-27 Channel setup The parameter is used to set up scan channels. For example, the following examples show how to set up scan channel 101: FUNC 'VOLT', (@101) VOLT:RANG 10, (@101) VOLT:DIG 4.5, (@101) VOLT:NPLC 3, (@101) NOTE ' ' ' ' Set Set Set Set 101 101 101 101 for DCV. for 10V range. for 4H digit resolution. rate for 3 PLC.
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7-28 Scanning Model 2700 Multimeter/Switch System User’s Manual Table 7-1 Scanning commands Commands Scan commands ROUTe:SCAN ROUTe:SCAN? ROUTe:SCAN:TSOurce Description Specify list of channels to be scanned. Returns list of channels to be scanned. Select trigger(s) to start scan; = IMMediate, or HLIMit1, LLIMit1, HLIMit2, LLIMit2. ROUTe:SCAN:NVOLatile Enable or disable auto scan; = ON or OFF.
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Model 2700 Multimeter/Switch System User’s Manual Scanning 7-29 Table 7-1 (continued) Scanning commands Commands Trigger commands TRIGger:SOURce Description Select control source; = IMMediate, TIMer, MANual, BUS, or EXTernal. Set timer interval in sec; = 0.001 to 999999.999. Set trigger count; = 1 to 55000, or INFinity. Set delay in sec; = 0 to 999999.999. Enable/disable auto delay; = ON or OFF. Set sample count; = 1 to 55000. Query sample count.
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7-30 Scanning Model 2700 Multimeter/Switch System User’s Manual Reference a. ROUTe:SCAN — Channels will be scanned in the order that they are listed. The following example shows the proper format for specifying channels in a scan list for a sequential scan: ROUT:SCAN (@101:110,201,204,206) For the above scan list, the scan will run starting with the lowest numbered channel (101) and then sequence up (forward) to the highest numbered channel (206).
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Model 2700 Multimeter/Switch System User’s Manual Scanning 7-31 For the 4-wire resistance function, channels 101through 110 will be paired to channels 111 through 120. ROUT:SCAN? returns the following scan list: (@101:110) Now assume the scan is returned to DCV function as follows: SENS:FUNC 'VOLT',(@101:120) The above command sets channels 101 through 120 for DCV. However, it will NOT affect the scan list.
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7-32 Scanning Model 2700 Multimeter/Switch System User’s Manual e. f. SAMPle:COUNt and TRIGger:COUNt — Sample count specifies the number of readings to scan and store in the buffer, while the trigger count specifies the number of scans to perform. If the sample count is greater than the number of channels in the scan list (scan list length), operation wraps around to the beginning of the scan list and continues.
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Model 2700 Multimeter/Switch System User’s Manual Scanning 7-33 Scanning examples The following scanning examples assume that the Model 7700 switching module is installed in slot 1 of the mainframe. Tables are used for the procedure steps to configure and run scan examples. The left side of the table provides the front panel procedure, while the right side shows the equivalent remote programming commands. Where appropriate, menu sequences are provided to summarize a front panel operation or selection.
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7-34 Scanning Model 2700 Multimeter/Switch System User’s Manual Operation A simplified model of external trigger scan operation is shown in Figure 7-4, while the procedure steps and programming commands are listed in Table 7-2. As shown in the operation model, when the scan is enabled, channel 101 closes and the Model 2700 waits for an external trigger. When the trigger is received, channels 101 and 102 are measured. Operation then returns to the control source where it waits for another trigger.
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Model 2700 Multimeter/Switch System User’s Manual Scanning Table 7-2 External trigger scan example Front panel operation 1 Restore defaults: Restore defaults (SHIFT SETUP > RESTORE: FACT). 2 For front panel operation, proceed to step 3. For remote programming, clear buffer and disable buffer auto clear: 3 a b c d e f Configure advanced scan: (SHIFT CONFIG > ADVANCED): Channel 101: Select TEMP function. Configure temperature (SHIFT SENSOR): Select thermocouple sensor (SENS: TCOUPLE).
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7-36 Scanning Model 2700 Multimeter/Switch System User’s Manual Monitor scan For this example, channel 101 of the Model 7700 is used to monitor temperature. When the temperature reading reaches 30°C, it will start the scan. For this 4-channel scan, channel 101 measures temperature, while channels 102, 103, and 104 measure DCV. This example uses the channel average feature to measure temperature.
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Model 2700 Multimeter/Switch System User’s Manual Scanning Figure 7-5 Monitor scan example Monitor Mode: Close Monitor Channel (101) No ≥30˚C ? Measure TEMP Scan Mode: Close First Channel Return to Monitor Mode Yes No 4 Measurements ? Open Last Chan Close Next Chan Measure Yes SCAN 7-37
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7-38 Scanning Model 2700 Multimeter/Switch System User’s Manual Table 7-3 Monitor scan example Front panel operation Remote programming 1 Restore defaults (SHIFT SETUP > RESTORE: FACT). SYST:PRES 2 For front panel operation, proceed to step 3. For remote programming, clear the buffer: TRAC:CLE 3 a b c d e f g 4 Configure advanced scan: SHIFT CONFIG > ADVANCED: Channel 101: Select TEMP function. Configure temperature (SHIFT SENSOR): Select Thermocouple sensor (SENS: TCOUPLE).
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8 Triggering • Trigger model — Explains the various components of the front panel trigger model, which controls the triggering operations of the instrument. • Reading hold — Explains the Reading Hold feature which is used to screen out readings that are not within a specified reading window. • External triggering — Explains external triggering which allows the Model 2700 to trigger and be triggered by other instruments.
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8-2 Triggering Model 2700 Multimeter/Switch System User’s Manual Trigger model The flow chart in Figure 8-1 summarizes triggering as viewed from the front panel. It is called a trigger model because it is modeled after the SCPI commands used to control triggering. NOTE For scanning, the trigger model has additional control blocks, such as a Timer. These are described in Section 7 (Figure 7-1 and Figure 7-2).
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Model 2700 Multimeter/Switch System User’s Manual Triggering 8-3 Idle When not scanning and in the continuous trigger mode (factory default setup), the instrument will not stay in idle. Operation will continuously fall through the idle state and proceed to the Event Detection block of the trigger model. When in the one-shot trigger mode (*RST default setup), the TRIG key must be pressed to take the instrument out of idle.
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8-4 Triggering Model 2700 Multimeter/Switch System User’s Manual Delay (auto or manual) A programmable 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 sufficient settling for function and autorange changes and multiphase measurements.
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Model 2700 Multimeter/Switch System User’s Manual Triggering 8-5 If MANual is chosen, also enter the duration of the delay in the hour/minute/second format using the , , Δ, and ∇ keys. The maximum is 99H:99M:99.999S:. Note that pressing the AUTO key sets the delay to 0.001 sec. Press ENTER to accept the delay or EXIT for no change. Device action The primary device action is a measurement.
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8-6 Triggering Model 2700 Multimeter/Switch System User’s Manual Output trigger After the device action, an output trigger occurs and is available at the rear panel Trigger Link connector. This trigger can be used to trigger another instrument to perform an operation (e.g., select the next channel for an external scan). Reading hold (autosettle) With hold enabled (HOLD annunciator on), the first processed reading becomes the “seed” reading and operation loops back within the device action block.
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Model 2700 Multimeter/Switch System User’s Manual Triggering 8-7 Beeper control The beeper for Hold can be enabled or disabled from the OUTPUT menu as follows: 1. 2. 3. 4. Press SHIFT and then OUTPUT. Use the Δ or ∇ key to display the present beeper (BEEP) state; NEVER, OUTSIDE, or INSIDE. Perform step a or b: a. To enable the beeper, use the Δ or ∇ key to display OUTSIDE or INSIDE. b. To disable the beeper, use the Δ or ∇ key to display NEVER. Press ENTER.
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8-8 Triggering Model 2700 Multimeter/Switch System User’s Manual Figure 8-3 TRIG LINK pinout Pin Number TRIG LINK Pinout 8 6 7 4 5 2 Pin 2 External Trigger Input 3 1 Pin 1 Voltmeter Complete Output Description 1 Voltmeter Complete Output 2 External Trigger Input 3 No Connection 4 No Connection 5 No Connection 6 No Connection 7 Signal Ground 8 Signal Ground External trigger The EXT TRIG input requires a falling-edge, TTL-compatible pulse with the specifications shown in Figure 8
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Model 2700 Multimeter/Switch System User’s Manual Triggering 8-9 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 are shown in Figure 8-5. Typically, you would want the Model 2700 to output a trigger after the settling time of each measurement. Figure 8-5 Trigger link output pulse specifications (VMC) Meter Complete TTL High (3.4V Typical) TTL Low (0.
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8-10 Triggering Model 2700 Multimeter/Switch System User’s Manual External triggering example For a test system that requires a large number of switching channels, the Model 2700 can be used with external scanners such as the Keithley Models 7001 and 7002. For example, 10 Model 7011s installed in the Model 7002 can provide up to 400 2-pole channels, as shown in Figure 8-6.
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Model 2700 Multimeter/Switch System User’s Manual Triggering 8-11 For this example, the Models 2700 and 7002 are configured as follows: Model 2700 Factory defaults restored (accessed from SHIFT-SETUP) External triggers (accessed from EX TRIG) Buffer enabled and set to store 400 readings Model 7002 Factory defaults restored Scan list = 1!1-1!400 Number of scans = 1 Channel spacing = TrigLink Figure 8-7 Trigger link connections Trigger Link Model 7002 WARNING: INTERCONNECTION, INSTALLATION AND REMOVAL
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8-12 Triggering Model 2700 Multimeter/Switch System User’s Manual 1. 2. Press EX TRIG to place the Model 2700 in the external trigger mode. Press STEP on the Model 7002 to take it out of idle and start the scan. The scanner’s output pulse triggers the Model 2700 to take a reading, store it, and send a trigger pulse. The following explanation on operation is referenced to the operation model shown in Figure 8-8.
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Model 2700 Multimeter/Switch System User’s Manual D. E & F. Triggering 8-13 After the relay settles, the Model 7002 outputs a Channel Ready pulse. Since the instrument is programmed to scan 400 channels, operation loops back up to point B, where it waits for an input trigger. Model 2700 operation is at point A waiting for a trigger. The output Channel Ready pulse from the Model 7002 triggers the Model 2700 to measure DUT #1 (point E).
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8-14 Triggering Model 2700 Multimeter/Switch System User’s Manual Figure 8-9 DIN to BNC trigger cable Model 220 Current Source 8503 DIN to BNC Trigger Cable INPUT External Trigger OUTPUT Trigger Link WARNING:NO INTERNAL OPERATOR SERVICABLE PARTS,SERVICE BY QUALIFIED PERSONNEL ONLY. DIGITAL I/O TRIG. LINK ! RS232 MADE IN U.S.A. IEEE-488 ! SLT 1 KEITHLEY SLOT COVER SLT 2 CAUTION:FOR CONTINUED PROTECTION AGAINST FIRE HAZARD,REPLACE FUSE WITH SAME TYPE AND RATING.
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Model 2700 Multimeter/Switch System User’s Manual • Triggering 8-15 *RST What happens next depends on the state of initiation. If continuous initiation is already enabled, the instrument will leave the idle state. SYSTem:PRESet enables continuous initiation. Therefore, operation will immediately leave the idle state when it is sent. The *RCL command will do the same if INITiation:CONTinuous ON is a user-saved default. *RST disables continuous initiation.
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8-16 Triggering Model 2700 Multimeter/Switch System User’s Manual Figure 8-10 Trigger model (remote operation) START :ABOrt *RCL 0 :SYST:PRES *RST Idle and Initiate :INIT (:IMM) or :INIT:CONT ON ? No No :INIT (:IMM) or :INIT:CONT ON ? Yes Yes No :Trigger:Signal Yes Control Source :Trigger:Source :Trigger:Source :Trigger:Source :Trigger:Source :Trigger:Source Event Detection Immediate External Timer Manual BUS Timer Enabled ? No :Trigger:Count | INFinity Yes Output Trigger Timer Bypass
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Model 2700 Multimeter/Switch System User’s Manual Triggering 8-17 Trigger model operation Once the instrument is taken out of idle, operation proceeds through the trigger model down to the device action. In general, the device action includes a measurement and, when scanning, closes the next channel. Control Source — As shown in Figure 8-10, a control source is used to hold up operation until the programmed event occurs.
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8-18 Triggering Model 2700 Multimeter/Switch System User’s Manual Output Trigger — The Model 2700 will send one or more output triggers. The output trigger is applied to the Trigger Link connector on the rear panel. It can be used to trigger an external instrument to perform an operation. The trigger model can be configured to output a trigger after the completion of a series of measurements, or after every measurement.
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Model 2700 Multimeter/Switch System User’s Manual Triggering 8-19 Reference a. b. c. d. ABORt — With continuous initiation disabled, the 2700 goes into the idle state. With continuous initiation enabled, operation continues at the top of the trigger model. INITiate — Whenever the instrument is operating within the trigger model, sending this command causes an error and will be ignored.
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8-20 Triggering Model 2700 Multimeter/Switch System User’s Manual Programming example The following program fragment triggers (and stores in the buffer) 10 readings. Note that in order to send the readings to the computer, you must address the Model 2700 to talk after sending READ?. *RST TRAC:CLE TRIG:DEL 0.5 SAMP:COUN 10 READ? ' ' ' ' ' Restore *RST defaults. Clear buffer. Set delay for 0.5sec. Set sample count to 10. Trigger, store, and request readings.
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9 Limits and Digital I/O • Limits — Explains how to perform limit tests on measured readings. • Digital I/O — Covers the digital I/O port. Explains how the five digital outputs respond to the results of limit tests. • Remote programming — limits and digital output — Summarizes the commands to perform limit tests and control the digital I/O port. • Application — sorting resistors — Provides an application to test the tolerances of 100Ω resistors.
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9-2 Limits and Digital I/O Model 2700 Multimeter/Switch System User’s Manual Limits NOTE Limits cannot be used with the CONT function. When using limits, you can set and control the values that determine the HIGH/IN/LOW status of subsequent measurements. The limit test is performed on the result of an enabled Rel, Math, Ratio, or Channel Average operation. NOTE The various instrument operations, including Limits, are performed on the input signal in a sequential manner.
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Model 2700 Multimeter/Switch System User’s Manual Limits and Digital I/O 9-3 Overflow readings — A reading that exceeds the present measurement range causes the “OVRFLW” message to be displayed. The “IN,” “1,” and “2” messages are not displayed while in the overflow condition. The HIGH annunciator will turn on to indicate an out of limits reading. The LOW annunciator is not used for an overflow reading.
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9-4 Limits and Digital I/O Model 2700 Multimeter/Switch System User’s Manual Scanning When a simple scan is configured, the present limit values and state will apply to all channels in the scan. When an advanced scan is configured, each channel can have its own unique limits configuration. Details to configure and run a scan are provided in Section 7. For remote programming, the parameter is used to configure channels for a scan.
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Model 2700 Multimeter/Switch System User’s Manual Limits and Digital I/O 9-5 Digital I/O Model 2700’s Digital I/O port is accessed at a male DB-9 connector located on the rear panel. The connector location and pin designations are shown in Figure 9-2. Figure 9-2 Digital I/O port Model 2700 WARNING:NO INTERNAL OPERATOR SERVICABLE PARTS,SERVICE BY QUALIFIED PERSONNEL ONLY. DIGITAL I/O TRIG. LINK ! RS232 MADE IN U.S.A.
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9-6 Limits and Digital I/O Model 2700 Multimeter/Switch System User’s Manual Digital outputs The digital I/O port has five digital outputs. Each digital output can be used as a sink to control devices (e.g., relays), or as a source to provide input to external logic (TTL or CMOS) circuitry. The simplified schematic for the digital outputs are shown in Figure 9-3. Note that this illustration shows the schematic for one digital output. All five digital output circuits are identical.
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Model 2700 Multimeter/Switch System User’s Manual Limits and Digital I/O 9-7 When a limit (LO1, HI2, LO2, HL2) is reached, the digital output line for that limit will be pulled high or low. When a reading is within the limit, the output line is released. Digital output 5 is the logical OR of the four limits. Therefore, if any of the four limits are reached or exceeded, output 5 will be pulled high or low.
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9-8 Limits and Digital I/O Model 2700 Multimeter/Switch System User’s Manual Sink mode — controlling external devices Each output can be operated from an external supply (voltage range from +5V to +33V applied through the external device being driven). The high current sink capacity of the output driver allows direct control of relays, solenoids, and lamps (no additional circuitry needed).
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Model 2700 Multimeter/Switch System User’s Manual Limits and Digital I/O 9-9 Figure 9-4 Controlling externally powered relays Model 2700 Pin 7 - Diode Clamp 33V +5V Digital Output #1 Flyback Diode 4.
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9-10 Limits and Digital I/O Model 2700 Multimeter/Switch System User’s Manual Source mode — logic control The digital outputs can be used as logic inputs to active TTL, low-power TTL, or CMOS inputs. For this mode of operation, the output lines can source up to 200µA. CAUTION Each output line can source up to 200µA. Exceeding 200µA may cause damage to Model 2700 that is not covered by the warranty. Figure 9-5 shows how to connect a logic device to one of the output lines.
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Model 2700 Multimeter/Switch System User’s Manual NOTE • • Limits and Digital I/O 9-11 The factory default pulse time is 2ms maximum. Using remote programming, pulse time can be set from 0.001 to 99999.999 sec. It cannot be set from the front panel. LSENSE — Use to select the logic sense: active HIGH or active LOW. With active high selected, an output will be at approximately +5V when a reading is at or exceeds the limit.
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9-12 Limits and Digital I/O 8. Model 2700 Multimeter/Switch System User’s Manual To retain the present pulse mode setting, press ENTER. Otherwise, press to move the cursor to the right, press Δ or ∇ key to display “NO” or “YES,” and press ENTER. Scanning While limits can be configured on a per scan channel basis, the digital output configuration cannot.
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Model 2700 Multimeter/Switch System User’s Manual Limits and Digital I/O 9-13 Table 9-2 (continued) Limits and digital I/O commands Commands* Description Def Ref Digital output commands CALCulate3:OUTPut:LSENse CALCulate3:OUTPut:[STATe] Set logic sense; = AHIGh or ALOW. AHIGh Enable/disable digital outputs; = ON or OFF OFF. CALCulate3:OUTPut:PULSe:TIME Set output pulse time in secs; = 0.001 0.002 to 99999.999.
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9-14 Limits and Digital I/O b. c. Model 2700 Multimeter/Switch System User’s Manual CALCulate3:LIMit1:FAIL? CALCulate3:LIMit2:FAIL? These commands are used to query the results of Limit 1 and Limit 2: 0 = Passing (reading within the high and low limits) 1 = Failing (reading has reached or exceeded the high or low limit) The “1” response message does not tell you which limit (high or low) has been reached.
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Model 2700 Multimeter/Switch System User’s Manual Limits and Digital I/O 9-15 Application — sorting resistors For this application, the idea is to sort a batch of 100Ω resistors into three bins. Bin 1 is for resistors that are within 1% of the nominal value. Bin 2 is for resistors that exceed 1% tolerance, but are within 5%. Bin 3 is for resistors that exceed 5% tolerance.
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9-16 Limits and Digital I/O Model 2700 Multimeter/Switch System User’s Manual Limit 1 will be used to test for the 1% tolerance and Limit 2 will be used to test for the 5% tolerance. The resistance values for the 1% and 5% tolerances are calculated as follows: R1% = 100Ω × 1% = 100Ω × 0.01 = 1Ω R5% = 100Ω × 5% = 100Ω × 0.
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Model 2700 Multimeter/Switch System User’s Manual Limits and Digital I/O 9-17 Remote Operation — For remote operation, make sure both Limit 1 and Limit 2 are enabled. The following table evaluates the three possible pass/fail combinations for this example. Limit 1 result Limit 2 result Resistor tolerance Bin assignment Pass Pass >1% 1 Fail Pass >5% 2 Fail Fail >5% 3 Keep in mind that a fail condition must be reset before testing the next resistor.
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9-18 Limits and Digital I/O Model 2700 Multimeter/Switch System User’s Manual
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10 Remote Operations • Operation enhancements — Summarizes some of the more important operations that can only be performed using remote operation. • GPIB setup — Covers GPIB bus standards, selecting the GPIB, primary address selection, and bus connections. • General bus commands — Describes general bus commands used for fundamental GPIB control. • Front panel GPIB operation — Summarizes GPIB error messages, status indicators, and using the LOCAL key.
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10-2 Remote Operations Model 2700 Multimeter/Switch System User’s Manual Operation enhancements There are some operations you can do over the IEEE-488 bus and RS-232 interface that you cannot do from the front panel. The more important ones are summarized below. Pseudocards Using remote operation, you can assign a pseudocard to an empty switching module slot. With a pseudocard installed, the Model 2700 will operate as if the switching module is installed in the Model 2700.
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Model 2700 Multimeter/Switch System User’s Manual Remote Operations 10-3 Separate function setups A few settings from the front panel are global. That is, the setting on one function also applies to the other functions. For example, if you set DCV for 3Hdigits, all the other functions will also be set to 3Hdigits. Using remote programming, each function can have its own unique setup. For example, DCV can be set to 3Hdigits, ACI can be set to 4Hdigits, and DCI can be set to 5Hdigits.
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10-4 Remote Operations Model 2700 Multimeter/Switch System User’s Manual GPIB setup The following provides information about GPIB standards, selecting the GPIB, setting the primary address, and bus connections. GPIB standards The GPIB is the IEEE-488 instrumentation data bus with hardware and programming standards originally adopted by the IEEE (Institute of Electrical and Electronic Engineers) in 1975. The Model 2700 conforms to these standards: • • IEEE-488.1-1987 IEEE-488.
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Model 2700 Multimeter/Switch System User’s Manual Remote Operations 10-5 GPIB connections To connect the Model 2700 to the GPIB bus, use a cable equipped with standard IEEE-488 connectors as shown in Figure 10-1. Figure 10-1 IEEE-488 connector To allow many parallel connections to one instrument, stack the connectors. Two screws are located on each connector to ensure that connections remain secure. Present standards call for metric threads, which are identified with dark-colored screws.
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10-6 Remote Operations Model 2700 Multimeter/Switch System User’s Manual Figure 10-2 shows a typical connecting scheme for a multi-unit test system. Figure 10-2 IEEE-488 connections Instrument Instrument Instrument Controller To avoid possible mechanical damage, stack no more than three connectors on any one unit. NOTE To minimize interference caused by electromagnetic radiation, use only shielded IEEE-488 cables. Available shielded cables from Keithley are Models 7007-1 and 7007-2.
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Model 2700 Multimeter/Switch System User’s Manual Remote Operations 10-7 To connect the Model 2700 to the IEEE-488 bus, follow these steps: 1. 2. 3. 4. NOTE Line up the cable connector with the connector located on the rear panel. The connector is designed so it will fit only one way. Figure 10-3 shows the location of the IEEE-488 connector. Tighten the screws securely, making sure not to overtighten them. Connect any additional connectors from other instruments as required for your application.
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10-8 Remote Operations Model 2700 Multimeter/Switch System User’s Manual General bus commands General commands are those commands, such as DCL, that have the same general meaning regardless of the instrument. Table 10-1 lists the general bus commands. Table 10-1 General bus commands Command REN IFC LLO GTL DCL SDC GET SPE, SPD Effect on Model 2700 Goes into effect when next addressed to listen. Goes into talker and listener idle states. LOCAL key locked out.
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Model 2700 Multimeter/Switch System User’s Manual Remote Operations 10-9 LLO (local lockout) Use the LLO command to prevent local operation of the instrument. After the unit receives LLO, all of its front panel controls except OUTPUT OFF are inoperative. In this state, pressing LOCAL will not restore control to the front panel. The GTL command restores control to the front panel. Cycling power will also cancel local lockout.
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10-10 Remote Operations Model 2700 Multimeter/Switch System User’s Manual Front panel GPIB operation This section describes aspects of the front panel that are part of GPIB operation, including messages, status indicators, and the LOCAL key. Error and status messages See Appendix C for a list of error and status messages associated with IEEE-488 programming. The instrument can be programmed to generate an SRQ, and command queries can be performed to check for specific error conditions.
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Model 2700 Multimeter/Switch System User’s Manual Remote Operations 10-11 SRQ You can program the instrument to generate a service request (SRQ) when one or more errors or conditions occur. When this indicator is on, a service request has been generated. This indicator stays on until the serial poll byte is read or all the conditions that caused SRQ have been cleared. See Section 11, “Status Structure,” for more information.
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10-12 Remote Operations Model 2700 Multimeter/Switch System User’s Manual These brackets indicate that IMMediate is implied (optional) and does not have to be used. Thus, the above command can be sent in one of two ways: INITiate or INITiate:IMMediate Notice that the optional command is used without the brackets. When using optional command words in your program, do not include the brackets.
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Model 2700 Multimeter/Switch System User’s Manual Angle brackets < > Remote Operations 10-13 Angle brackets (< >) are used to denote a parameter type. Do not include the brackets in the program message. For example: RATio The indicates a Boolean-type parameter is required. Therefore, to enable channel ratio, you must send the command with the ON or 1 parameter as follows: RATio ON RATIO 1 Query commands This type of command requests (queries) the presently programmed status.
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10-14 Remote Operations Model 2700 Multimeter/Switch System User’s Manual Long-form and short-form versions An SCPI command word can be sent in its long-form or short-form version. The command subsystem tables in Section 15 provide the long-form version. However, the short-form version is indicated by upper case characters.
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Model 2700 Multimeter/Switch System User’s Manual Remote Operations 10-15 Program messages A program message is made up of one or more command words sent by the computer to the instrument. Each common command is a three letter acronym preceded by an asterisk (*). SCPI commands are categorized in the STATus subsystem and are used to explain how command words are structured to formulate program messages.
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10-16 Remote Operations Model 2700 Multimeter/Switch System User’s Manual Command path rules • • • • • Each new program message must begin with the root command, unless it is optional (e.g., [SENSe]). If the root is optional, simply treat a command word on the next level as the root. For fastest operation, do not send optional data. A colon (:) can be used at the beginning of a program message. However, using the colon slows down execution time.
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Model 2700 Multimeter/Switch System User’s Manual Remote Operations 10-17 Response messages A response message is the message sent by the instrument to the computer in response to a query command program message. Sending a response message After sending a query command, the response message is placed in the Output Queue. When the Model 2700 is then addressed to talk, the response message is sent from the Output Queue to the computer.
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10-18 Remote Operations Model 2700 Multimeter/Switch System User’s Manual RS-232 interface operation Sending and receiving data The RS-232 interface transfers data using eight data bits, one stop bit, and no parity. Make sure the controller you connect to the multimeter also uses these settings. You can break data transmissions by sending a ^C (decimal 3) or ^X (decimal 18) character string to the instrument. This clears any pending operation and discards any pending output.
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Model 2700 Multimeter/Switch System User’s Manual Remote Operations 10-19 Signal handshaking (flow control) Signal handshaking between the controller and the instrument allows the two devices to communicate to each other regarding being ready or not ready to receive data. The Model 2700 does not support hardware handshaking (flow control). Software flow control is in the form of X__ON and X__OFF characters and is enabled when XonXoFF is selected from the RS232 FLOW menu.
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10-20 Remote Operations Model 2700 Multimeter/Switch System User’s Manual Selecting and configuring RS-232 interface After selecting (enabling) the RS-232 interface, you will then set the baud rate, flow control, and terminator. 1. 2. Press the SHIFT key and then the RS-232 key. The RS 232 ON or RS 232 OFF message will be displayed. If the RS-232 is already ON, press ENTER and proceed to step 3.
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Model 2700 Multimeter/Switch System User’s Manual Figure 10-4 RS-232 interface connector 5 4 3 2 1 9 8 7 6 Rear Panel Connector Remote Operations 10-21
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10-22 Remote Operations Model 2700 Multimeter/Switch System User’s Manual Table 10-2 RS-232 connector pinout Pin number 1 2 3 4 5 6 7 8 9 1CTS Description No connection TXD, transmit data RXD, receive data No connection GND, signal ground Not used RTS, ready to send1 CTS, clear to send1 No connection and RTS are not used. Table 10-3 provides pinout identification for the 9-pin (DB-9) or 25-pin (DB-25) serial port connector on the computer (PC).
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11 Status Structure • Overview — Provides an operational overview of the status structure for the Model 2700. • Clearing registers and queues — Covers the actions that clear (reset) registers and queues. • Programming and reading registers — Explains how to program enable registers and read any register in the status structure. • Status byte and service request (SRQ) — Explains how to program the Status Byte to generate service requests (SRQs).
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11-2 Status Structure Model 2700 Multimeter/Switch System User’s Manual Overview The Model 2700 provides a series of status registers and queues allowing the operator to monitor and manipulate the various instrument events. The status structure is shown in Figure 11-1. The heart of the status structure is the Status Byte Register. This register can be read by the user’s test program to determine if a service request (SRQ) has occurred, and what event caused it.
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Model 2700 Multimeter/Switch System User’s Manual Status Structure 11-3 Figure 11-1 Model 2700 status register structure Questionable Questionable Questionable Condition Event Event Enable Register Register Register Temperature Summary Calibration Summary Command Warning (Always Zero) 0 1 2 3 Temp 5 6 7 Cal 9 10 11 12 13 Warn 15 Standard Event Status Register Operation Complete OPC 1 Query Error QYE Device-Dependent Error DDE Execution Error EXE Command Error CME User Request URQ Power On PON 8 9 10
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11-4 Status Structure Model 2700 Multimeter/Switch System User’s Manual Clearing registers and queues When the Model 2700 is turned on, the bits of all registers in the status structure are cleared (reset to 0), and the two queues are empty. Commands to reset the event and event enable registers, and the Error Queue are listed in Table 11-1. In addition to these commands, any enable register can be reset by sending the 0 parameter value with the individual command to program the register.
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Model 2700 Multimeter/Switch System User’s Manual Status Structure 11-5 Programming and reading registers Programming enable registers The only registers that can be programmed by the user are the enable registers. All other registers in the status structure are read-only registers. The following explains how to ascertain the parameter values for the various commands used to program enable registers. The actual commands are covered later in this section (Table 11-2 and Table 11-5).
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11-6 Status Structure Model 2700 Multimeter/Switch System User’s Manual Reading registers Any register in the status structure can be read by using the appropriate query (?) command. The following explains how to interpret the returned value (response message). The actual query commands are covered later in this section (Table 11-2 through Table 11-5). The response message for a register query will be a decimal value. This decimal value will have to be converted to its binary equivalent.
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Model 2700 Multimeter/Switch System User’s Manual Status Structure 11-7 Status byte register The summary messages from the status registers and queues are used to set or clear the appropriate bits (B0, B2, B3, B4, B5, and B7) of the Status Byte Register. These summary bits do not latch, and their states (0 or 1) are solely dependent on the summary messages (0 or 1). For example, if the Standard Event Register is read, its register will clear.
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11-8 Status Structure Model 2700 Multimeter/Switch System User’s Manual Service request enable register The generation of a service request is controlled by the Service Request Enable Register. This register is programmed by you and is used to enable or disable the setting of bit B6 (RQS/MSS) by the Status Summary Message bits (B0, B2, B3, B4, B5, and B7) of the Status Byte Register.
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Model 2700 Multimeter/Switch System User’s Manual Status Structure 11-9 Status byte and service request commands The commands to program and read the Status Byte Register and Service Request Enable Register are listed in Table 11-2. For details on programming and reading registers, see “Programming enable registers,” page 11-5, and “Reading registers,” page 11-6. NOTE To reset the bits of the Service Request Enable Register to 0, use 0 as the parameter value for the *SRE command (*SRE 0).
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11-10 Status Structure Model 2700 Multimeter/Switch System User’s Manual Serial poll programming example This example is written specifically for the KPCI-488.2 GPIB card and QuickBasic/ VisualBasic with the appropriate IEEE libraries. Other types of cards and/or languages may have different function calls that are equivalent to the initialize(), transmit(), send(), srq, and spoll() calls used below.
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Model 2700 Multimeter/Switch System User’s Manual Status Structure 11-11 ' $INCLUDE: 'ieeeqb.bi' CLS CONST addr = 16 ' Clear PC output screen. ' Set instrument address. ' ' Init GPIB. ' CALL initialize(21, 0) CALL transmit("unt unl listen " + STR$(addr) + " sdc unl", status%)' Send Device Clear.
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11-12 Status Structure Model 2700 Multimeter/Switch System User’s Manual Status register sets As shown in Figure 11-1, there are four status register sets in the status structure of the Model 2700: Standard Event Status, Operation Event Status, Measurement Event Status, and Questionable Event Status.
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Model 2700 Multimeter/Switch System User’s Manual • • • • • • • Status Structure 11-13 Bit B1 — Not used. Bit B2, Query Error (QYE) — Set bit indicates that you attempted to read data from an empty Output Queue. Bit B3, Device-Dependent Error (DDE) — Set bit indicates that an instrument operation did not execute properly. Some of the errors specific to the Model 2700 that will set this bit include the following: • Error +516: Battery backed RAM error — Data stored in RAM has been lost.
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11-14 Status Structure Model 2700 Multimeter/Switch System User’s Manual Operation event register The bits of the Operation Event Register (Figure 11-5) are described as follows: • • • • • • • • Bits B0 through B3 — Not used. Bit B4, Measuring (Meas) — Set bit indicates that the instrument is performing a measurement. Bit B5, Waiting for Trigger (Trig) — Set bit indicates that the Model 2700 is in the trigger layer waiting for a trigger event to occur. Bits B6 and B7 — Not used.
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Model 2700 Multimeter/Switch System User’s Manual Status Structure 11-15 Measurement event register The used bits of the Measurement Event Register (Figure 11-6) are described as follows: • • • • • • NOTE • • • • NOTE • • • NOTE Bit B0, Reading Overflow (ROF) — Set bit indicates that the reading exceeds the measurement range of the instrument. Bit B1, Low Limit 1 Event (LL1) — Set bit indicates that a reading has reached or exceeded Low Limit 1.
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11-16 Status Structure • • • Model 2700 Multimeter/Switch System User’s Manual Bit B13, Buffer Three-Quarter Full (BTF) — Set bit indicates that the trace buffer is three-quarters full. Bit B14, Master Limit (ML) — Set bit indicates that one or more of the other limits have been reached or exceeded. Bit B15 — Not used.
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Model 2700 Multimeter/Switch System User’s Manual Status Structure 11-17 Questionable event register The used bits of the Questionable Event Register (Figure 11-7) are described as follows: • • • • • • • NOTE Bits B0 through B3 — Not used. Bit B4, Temperature Summary (Temp) — Set bit indicates that an invalid reference junction measurement has occurred for thermocouple temperature measurements. Bits B5, B6 and B7 — Not used.
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11-18 Status Structure Model 2700 Multimeter/Switch System User’s Manual Condition registers As Figure 11-1 shows, each status register set (except the Standard Event Register set) has a condition register. A condition register is a real-time, read-only register that constantly updates to reflect the present operating conditions of the instrument. For example, while the Model 2700 is in the idle state, bit B10 (Idle) of the Operation Condition Register will be set.
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Model 2700 Multimeter/Switch System User’s Manual Status Structure 11-19 Event enable registers As Figure 11-1 shows, each status register set has an enable register. Each event register bit is logically ANDed (&) to a corresponding enable bit of an enable register. Therefore, when an event bit is set and the corresponding enable bit is set (as programmed by the user), the output (summary) of the register will set to 1, which in turn sets the summary bit of the Status Byte Register.
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11-20 Status Structure Model 2700 Multimeter/Switch System User’s Manual Programming examples Example 1 – Program and read a register set NOTE The following example can be run from the KE2700 Instrument Driver using the example named “Prmr” in Table H-1 of Appendix H. The following command sequence programs and reads the measurement register set: STAT:MEAS:ENAB 512 STAT:MEAS:COND? STAT:MEAS? NOTE ' Enable BFL (buffer full). ' Read Measurement Condition Register. ' Read Measurement Event Register.
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Model 2700 Multimeter/Switch System User’s Manual Status Structure 11-21 As shown in the above result for the AND operation, when B0 is set, your program routine will generate a “1” to indicate that RAV is set. If B0 is not set (0), the AND operation will result in “0” to indicate that RAV is not set. Example 3 – Read BHF bit of measurement event register The buffer half full bit (BHF) is read in the same manner that the RAV bit was read in Example 2.
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11-22 Status Structure Model 2700 Multimeter/Switch System User’s Manual Queues The Model 2700 uses two queues, which are first-in, first-out (FIFO) registers: • • Output Queue — Used to hold reading and response messages. Error Queue — Used to hold error and status messages. The Model 2700 status model (Figure 11-1) shows how the two queues are structured with the other registers. Output queue The Output Queue holds data that pertains to the normal operation of the instrument.
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Model 2700 Multimeter/Switch System User’s Manual Status Structure 11-23 On power-up, all error messages are enabled and will go into the Error Queue as they occur. Status messages are not enabled and will not go into the queue. As listed in Table 11-6, there are commands to enable and/or disable messages. For these commands, the parameter is used to specify which messages to enable or disable. The messages are specified by their codes.
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11-24 Status Structure Model 2700 Multimeter/Switch System User’s Manual
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12 Common Commands
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12-2 Common Commands Model 2700 Multimeter/Switch System User’s Manual Common commands (summarized in Table 12-1) are device commands that are common to all devices on the bus. These commands are designated and defined by the IEEE-488.2 standard. Table 12-1 IEEE-488.2 common commands and queries Mnemonic *CLS *ESE *ESE? *ESR? Name Clear status Event enable command Event enable query Event status register query Description Clears all event registers and error queue.
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Model 2700 Multimeter/Switch System User’s Manual Common Commands A *IDN? — identification query 12-3 Reads identification code The identification code includes the manufacturer, model number, serial number, and firmware revision levels and is sent in the following format: KEITHLEY INSTRUMENTS INC., Model 2700, xxxxxxx, yyyyy/zzz Where: xxxxxxx is the serial number. yyyyy/zzzzz is the firmware revision levels of the digital board ROM and display board ROM.
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12-4 Common Commands Model 2700 Multimeter/Switch System User’s Manual After addressing the Model 2700 to talk, the returned value of 1 denotes that the bit (bit 1) is set indicating that the :INITiate operation is now complete. SYST:PRES ‘ Returns 2700 to default setup. NOTE The following commands take a long time to process and may benefit from using *OPC or *OPC?: • • • • *RST and SYST:PRES *RCL and *SAV ROUT:MULT:CLOS and ROUT:MULT:OPEN – Only if the is long.
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Model 2700 Multimeter/Switch System User’s Manual Common Commands 12-5 Programming example – The following command sequence demonstrates how to use *OPC? to signal the end of a measurement process: NOTE The following example can be run from the KE2700 Instrument Driver using the example named “SOPC” in Table H-1 of Appendix H. SYST:PRES INIT:CONT OFF ABORt TRIG:COUN 1 SAMP:COUN 5 INIT *OPC? ‘ ‘ ‘ ‘ ‘ ‘ ‘ Returns 2700 to default setup. Disables continuous initiation. Aborts operation.
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12-6 Common Commands Model 2700 Multimeter/Switch System User’s Manual D *OPT? — option query Query installed switching modules Use this query command to determine which switching modules are installed in the Model 2700. For example, if a Model 7703 is installed in slot 1, and the other slot is empty, the response message will look like this: 7703, NONE Note that the model number of an installed pseudocard is returned in the same manner. See Section 2 for details on pseudocards.
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Model 2700 Multimeter/Switch System User’s Manual F Common Commands *RST — reset 12-7 Return Model 2700 to RST defaults When the *RST command is sent, Model 2700 performs the following operations: 1. 2. 3. NOTE Returns Model 2700 to the RST default conditions (see “Default” column of SCPI tables). Cancels all pending commands. Cancels response to any previously received *OPC and *OPC? commands.
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12-8 Common Commands I Model 2700 Multimeter/Switch System User’s Manual *WAI — Wait-to-Continue Prevent execution of commands until previous commands are completed Description Two types of device commands exist: • • Sequential commands – A command whose operations are allowed to finish before the next command is executed. Overlapped commands – A command that allows the execution of subsequent commands while device operations of the Overlapped command are still in progress.
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13 SCPI Signal Oriented Measurement Commands
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13-2 SCPI Signal Oriented Commands Model 2700 Multimeter/Switch System User’s Manual The signal oriented measurement commands are used to acquire readings. You can use these high level instructions to control the measurement process. These commands are summarized in Table 13-1. NOTE When measurements are performed, the readings are fed to other enabled operations.
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Model 2700 Multimeter/Switch System User’s Manual SCPI Signal Oriented Commands 13-3 NOTES The CONFigure: and MEASure:? commands can be sent without any of the optional parameters (, , ). For details, see the “Description” for the CONFigure and MEASure commands. When using the parameter, it is interpreted as the last parameter. Any parameter after will generate error -102 (syntax error).
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13-4 SCPI Signal Oriented Commands Model 2700 Multimeter/Switch System User’s Manual CONFigure: [], [], [] CONFigure:VOLTage[:DC] [], [], [] CONFigure:VOLTage:AC [], [], [] CONFigure:CURRent[:DC] [], [], [] CONFigure:CURRent:AC [], [], [] CONFigure:RESistance [], [], [] CONFigure:FRESistance [], [], [] CONFigure:FREQuency [], [], [] CONFigure:PERiod [
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Model 2700 Multimeter/Switch System User’s Manual SCPI Signal Oriented Commands 13-5 Query CONFigure? Description included — When the parameter is included with CONFigure command, the specified channel(s) for the scanlist assumes the *RST default settings for the specified function. Range can also be set for the channel(s) by including the parameter. If the resolution parameter () is included, it will be ignored. Query the selected function.
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13-6 SCPI Signal Oriented Commands Model 2700 Multimeter/Switch System User’s Manual FETCh? Description This command requests the latest post-processed reading. After sending this command and addressing the Model 2700 to talk, the reading is sent to the computer. This command does not affect the instrument setup. This command does not trigger a measurement. The command simply requests the last available reading. FETCh? can also be used to return more than one reading.
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Model 2700 Multimeter/Switch System User’s Manual SCPI Signal Oriented Commands 13-7 READ? Description This command is typically used with the instrument in the “one-shot” measurement mode to trigger and acquire a specified number of readings. The SAMPle:COUNt command is used to specify the number of readings (see Trigger Subsystem). Note that with sample count >1, the readings are stored in the buffer.
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13-8 SCPI Signal Oriented Commands Model 2700 Multimeter/Switch System User’s Manual MEASure:? [], [], [] MEASure:VOLTage[:DC]? [], [], [] MEASure:VOLTage:AC? [], [], [] MEASure:CURRent[:DC]? [], [], [] MEASure:CURRent:AC? [], [], [] MEASure:RESistance? [], [], [] MEASure:FRESistance? [], [], [] MEASure:FREQuency? [], [], [] MEASure:PERiod? [], [<
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Model 2700 Multimeter/Switch System User’s Manual SCPI Signal Oriented Commands 13-9 Depending on the specified resolution, the measurement rate is set as follows: 6H-digits 5H-digits 3Hor 4H-digits NPLC = 1.0 NPLC = 0.1 NPLC = 0.01 Medium Fast >Fast If resolution is not specified, 6H-digit resolution and medium speed will be selected when MEAS? is sent. All other instrument settings related to the selected function are reset to the *RST defaults.
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13-10 SCPI Signal Oriented Commands Model 2700 Multimeter/Switch System User’s Manual
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14 FORMat and Miscellaneous SYSTem 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.
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14-2 FORMat and Misc SYSTem Commands Model 2700 Multimeter/Switch System User’s Manual FORMat commands The commands in this subsystem are used to select the format for transferring data, Table 14-1, over the bus. Table 14-1 SCPI commands — data format Command Description FORMat[:DATA] [,] FORMat:ELEMents FORMat:BORDer Default Specify data format; ASCii, SREal, REAL, 32, ASCii DREal, or REAL, 64.
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Model 2700 Multimeter/Switch System User’s Manual FORMat and Misc SYSTem Commands 14-3 ASCII data format The ASCII data format is in a direct readable form for the operator. Most programming languages easily convert ASCII mantissa and exponent to other formats. However, some speed is compromised to accommodate the conversion. Figure 14-1 shows an example ASCII string that includes all the data elements. See “FORMat:ELEMents ,” page 14-6, for information on the data elements.
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14-4 FORMat and Misc SYSTem Commands Model 2700 Multimeter/Switch System User’s Manual IEEE-754 binary formats Binary data from the instrument can be returned using the single precision format or the double precision format. The data can be returned in the normal byte order or the swapped (reversed) byte order. See “FORMat:BORDer ” for details on byte order. A returned data string from the instrument is made of one or more data elements.
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Model 2700 Multimeter/Switch System User’s Manual FORMat and Misc SYSTem Commands Figure 14-2 IEEE-754 data formats A. Single precision data format (32 data bits) Data Element Byte 1 Byte 2 7 07 Byte 3 Byte 4 0 7 0 7 s e s = sign bit (0 = positive, 1 = negative) e = exponent bits (8) f = fraction bits (23) 0 f Normal byte order shown. For swapped byte order, bytes sent in reverse order: Header, Byte 4, Byte 3, Byte 2, Byte 1. B.
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14-6 FORMat and Misc SYSTem Commands Model 2700 Multimeter/Switch System User’s Manual FORMat:ELEMents Parameters READing UNITs TSTamp RNUMber CHANnel LIMits = DMM reading = Units = Timestamp = Reading number = Channel number = Limits reading The specified elements are included in the data string in response to FETCh?, READ?, MEASure?, and TRACe:DATA?. Note that each element in the item list must be separated by a comma (i.e.
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Model 2700 Multimeter/Switch System User’s Manual FORMat and Misc SYSTem Commands 14-7 Limits — For the ASCII data format, limit test results are returned as a 4-bit binary number “abcd” where: a = High limit 2 b = Low limit 2 c = High limit 1 d = Low limit 1 A “0” indicates that the limit has passed, while a “1” indicates that the limit has failed. For the binary data formats, the limits information must be decoded from the returned value (0 to 15).
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14-8 FORMat and Misc SYSTem Commands Model 2700 Multimeter/Switch System User’s Manual Miscellaneous SYSTem commands SYSTem commands not covered in other sections of the manual are documented here. Table 15-7 lists all SYSTem commands and provides references on where to find more information. SYSTem:PRESet Returns the instrument to states optimized for front panel operation. SYSTem:PRESet defaults are listed in the SCPI tables in Section 15.
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Model 2700 Multimeter/Switch System User’s Manual FORMat and Misc SYSTem Commands 14-9 This command is used to simulate front panel key presses. For example, to select the volts measurement function, send the following command to simulate pressing the “DCV” key: SYSTem:KEY 2. The key-press codes are also shown in Figure 14-3. The queue for the :KEY? query command can only hold one key-press.
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14-10 FORMat and Misc SYSTem Commands Model 2700 Multimeter/Switch System User’s Manual
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15 SCPI Reference Tables
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15-2 SCPI Reference Tables Model 2700 Multimeter/Switch System User’s Manual Reference tables Table 15-1 through Table 15-10 summarize the commands to operate the Model 2700 and Model 7700 switching module. NOTE The commands listed in the following tables pertain to operation of the Model 2700 and the Model 7700 switching module. For commands that are unique to operation of other switching modules, refer to the packing list provided with each switch module.
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Model 2700 Multimeter/Switch System User’s Manual SCPI Reference Tables 15-3 Table 15-1 CALCulate command summary Command Description CALCulate[1] Subsystem to control CALC 1: :FORMat Select math format (NONE, MXB, PERCent, or [<, clist>] RECiprocal). :FORMat? [] Query math format. :KMATh Path to configure math calculations: :MMFactor Set “m” factor for mx+b (-4294967295 to [, ] +4294967295).1 :MA1Factor Set “m” factor for mx+b (-4294967295 to [, ] +4294967295).
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15-4 SCPI Reference Tables Model 2700 Multimeter/Switch System User’s Manual Table 15-1 (continued) CALCulate command summary Command CALCulate3 :MLIMit :LATChed :OUTPut [:STATe] [:STATe]? :PULSe [:STATe] [:STATe]? :TIME Description Subsystem to control CALC 3 (limit test): Path for master limit command: Enable or disable master limit latch. Path for limit output commands: Enable or disable limit outputs. Query state of limit outputs.
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Model 2700 Multimeter/Switch System User’s Manual SCPI Reference Tables 15-5 Table 15-1 (continued) CALCulate command summary Command CALCulate3 :LIMit2 :UPPer [:DATA] [, ] [:DATA]? [] :LOWer [:DATA] [, ] [:DATA]? [] :STATe [, ] :STATe? [] :FAIL? :CLEAR [:IMMediate] :AUTO :AUTO? Description Path to control LIMIT 2 test: Path to configure upper limit: Set upper limit (-4294967295 to +4294967295). Query upper limit.
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15-6 SCPI Reference Tables Model 2700 Multimeter/Switch System User’s Manual Table 15-2 DISPlay command summary Command DISPlay [:WINDow[1]] :TEXT :DATA :DATA? :STATe :STATe? :ENABle :ENABle? Description Default parameter Ref SCPI (see Note) Sec 1 Path to control user text messages. ASCII message “a” (up to 12 characters). Query text message. Enable or disable message mode. Query text message state. Enable or disable the front panel display. Query state of the display.
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Model 2700 Multimeter/Switch System User’s Manual SCPI Reference Tables 15-7 Table 15-4 ROUTe command summary Command ROUTe :MONitor :STATe :STATe? :DATA? :POINts :POINts? :MONitor? :CLOSe :STATe? :ACONfigure :ACONfigure? :COUNt? :INTerval :INTerval? :CLOSe? :OPEN:ALL Description Specify one channel to be monitored. Enable or disable channel monitoring. Query state of channel monitoring. Returns the most recent monitor reading.
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15-8 SCPI Reference Tables Model 2700 Multimeter/Switch System User’s Manual Table 15-4 (continued) ROUTe command summary Command ROUTe :MULTiple :OPEN :CLOSe :STATe? :CLOSe? :SCAN [:INTernal] [:INTernal]? :TSOurce :TSOurce? :NVOLatile :NVOLatile? :LSELect :LSELect? Description Path to control multiple channels: Open channel(s) specified in list. Unlisted channels not affected. Close channel(s) specified in list4. Unlisted channels not affected.
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Model 2700 Multimeter/Switch System User’s Manual SCPI Reference Tables 15-9 Table 15-5 SENSe command summary Command [SENSe[1]] :FUNCtion [, ] :FUNCtion? [] :DATA[:LATest]? :DATA:FRESh? :HOLD :WINDow :WINDow? :COUNt :COUNt? :STATe :STATe? :CAVerage [, ] :DELay [, ] :DELay? [] [:STATe] [, ] [:STATe]? [, ] :RATio [, ] :DELay [, ] :DELay? [] [:STATe] [, ] [:STATe]? [, ]
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15-10 SCPI Reference Tables Model 2700 Multimeter/Switch System User’s Manual Table 15-5 (continued) SENSe command summary Command [SENSe[1]] :VOLTage[:DC] :APERture [, ] :APERture? [] :NPLCycles [, ] :NPLCycles? [] :RANGe [:UPPer] [, ] [:UPPer]? [] :AUTO [, ] :AUTO? [] :DIGits [, ] :DIGits? [] :REFerence [, ] :STATe [, ] :STATe? [] :ACQuire [, ] :REFerence? [] :AVERage :TC
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Model 2700 Multimeter/Switch System User’s Manual SCPI Reference Tables 15-11 Table 15-5 (continued) SENSe command summary Command [SENSe[1]] :VOLTage:AC :APERture [, ] :APERture? [] :NPLCycles [, ] :NPLCycles? [] :RANGe [:UPPer] [, ] [:UPPer]? [] :AUTO [, ] :AUTO? [] :DIGits [, ] :DIGits? [] :REFerence [, ] :STATe [, ] :STATe? [] :ACQuire [, ] :REFerence? [] :AVERage :TCON
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15-12 SCPI Reference Tables Model 2700 Multimeter/Switch System User’s Manual Table 15-5 (continued) SENSe command summary Command [SENSe[1]] :CURRent[:DC] :APERture [, ] :APERture? [] :NPLCycles [, ] :NPLCycles? [] :RANGe [:UPPer] [, ] [:UPPer]? [] :AUTO [, ] :AUTO? [] :DIGits [, ] :DIGits? [] :REFerence [, ] :STATe [, ] :STATe? [] :ACQuire [, ] :REFerence? [] :AVERage :TC
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Model 2700 Multimeter/Switch System User’s Manual SCPI Reference Tables 15-13 Table 15-5 (continued) SENSe command summary Command [SENSe[1]] :CURRent:AC :APERture [, ] :APERture? [] :NPLCycles [, ] :NPLCycles? [] :RANGe [:UPPer] [, ] [:UPPer]? [] :AUTO [, ] :AUTO? [] :DIGits [, ] :DIGits? [] :REFerence [, ] :STATe [, ] :STATe? [] :ACQuire [, ] :REFerence? [] :AVERage :TCONtr
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15-14 SCPI Reference Tables Model 2700 Multimeter/Switch System User’s Manual Table 15-5 (continued) SENSe command summary Command [SENSe[1]] :RESistance :APERture [, ] :APERture? [] :NPLCycles [, ] :NPLCycles? [] :RANGe [:UPPer] [, ] [:UPPer]? [] :AUTO [, ] :AUTO? [] :DIGits [, ] :DIGits? [] :REFerence [, ] :STATe [, ] :STATe? [] :ACQuire [, ] :REFerence? [] :AVERage :TCON
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Model 2700 Multimeter/Switch System User’s Manual SCPI Reference Tables 15-15 Table 15-5 (continued) SENSe command summary Command [SENSe[1]] :FRESistance :APERture [, ] :APERture? [] :NPLCycles [, ] :NPLCycles? [] :RANGe [:UPPer] [, ] [:UPPer]? [] :AUTO [, ] :AUTO? [] :DIGits [, ] :DIGits? [] :REFerence [, ] :STATe [, ] :STATe? [] :ACQuire [, ] :REFerence? [] :AVERage :TCO
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15-16 SCPI Reference Tables Model 2700 Multimeter/Switch System User’s Manual Table 15-5 (continued) SENSe command summary Command [SENSe[1]] :TEMPerature :APERture [, ] :APERture? [] :NPLCycles [, ] :NPLCycles? :DIGits [, ] :DIGits? [] :REFerence [, ] :STATe [, ] :STATe? [] :ACQuire [, ] :REFerence? [] :AVERage :TCONtrol :TCONtrol? :WINDow :WINDow? :COUNt [, ] :COUNt? [] [:STATe]
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Model 2700 Multimeter/Switch System User’s Manual SCPI Reference Tables 15-17 Table 15-5 (continued) SENSe command summary Command [SENSe[1]] :TEMPerature :TCouple :TYPE [, ] :TYPE? [] :ODETect :ODETect? :RJUNction :RSELect [, ] :RSELect? [] :SIMulated [, ] :SIMulated? [] :THERmistor [:TYPE] [, ] [:TYPE]? [] :FRTD :TYPE [, ] :TYPE? [] :RZERo [, ] :RZERo? [] :ALPHa [, ]
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15-18 SCPI Reference Tables Model 2700 Multimeter/Switch System User’s Manual Table 15-5 (continued) SENSe command summary Command [SENSe[1]] :FREQuency :APERture [, ] :APERture? [] :DIGits [, ] :DIGits? [] :REFerence [, ] :STATe [, ] :STATe? [] :ACQuire [, ] :REFerence? [] :THReshold :VOLTage :RANGe [, ] :RANGe? [] :PERiod :APERture [, ] :APERture? [] :DIGits [, ] :DIGits? [
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Model 2700 Multimeter/Switch System User’s Manual SCPI Reference Tables 15-19 Table 15-5 (continued) SENSe command summary Command [SENSe[1]] :CONTinuity :THReshold :THReshold? Description Path to configure continuity test: Set threshold resistance in ohms (1 to 1000). Query threshold resistance. Default parameter Ref SCPI Sec 3 10 Notes: 1. CAVerage:DELay and RATio:DELay are coupled. Changing the delay for channel average also changes the delay for channel ratio, and vice versa. 2.
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15-20 SCPI Reference Tables Model 2700 Multimeter/Switch System User’s Manual Table 15-6 STATus command summary Command STATus :MEASurement [:EVENt]? :ENABle :ENABle? :CONDition? :OPERation [:EVENt]? :ENABle :ENABle? :CONDition? :QUEStionable [:EVENt]? :ENABle :ENABle? :CONDition? :PRESet :QUEue [:NEXT]? :ENABle :ENABle? :DISable :DISable? :CLEar Description Path to control measurement event registers: Read the event register. Program the enable register.
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Model 2700 Multimeter/Switch System User’s Manual SCPI Reference Tables 15-21 Table 15-7 SYSTem command summary Command SYSTem :PRESet :POSetup :POSetup? :FRSWitch? :BEEPer [:STATe] [:STATe]? :KCLick :KCLick? :KEY :KEY? :AZERo [:STATe] [:STATe]? :LSYNc [:STATe] [:STATe]? :LFRequency? :FRESistance :TYPEx :TYPEx? :PCARdX :CARDX :SNUMber? :SWRevision? :VMAX? :MUX? :ISOLated? :TCOMpensated? :VCHannel Description Return to :SYST:PRES defaults.
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15-22 SCPI Reference Tables Model 2700 Multimeter/Switch System User’s Manual Table 15-7 (continued) SYSTem command summary Command SYSTem :CARDX [:STARt]? :END? :ACHannel [:STARt]? :END? :ICHannel [:STARt]? :END? :AOUTput [:STARt]? :END? :DOUTput [:STARt]? :END? :TCHannel? :DINPut [:STARt]? :END? :SNOpen? Description Request lowest numbered volts/2-wire channel (usually 1); 0 = voltage measurements not supported. Request highest numbered volts/2-wire channel. 0 = voltage measurements not supported.
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Model 2700 Multimeter/Switch System User’s Manual SCPI Reference Tables 15-23 Table 15-7 (continued) SYSTem command summary Command SYSTem :CARDX :BANKs? :SWOpen? :BANKs? :CSOhms? :TIME :TIME? :DATE :DATE? :TSTamp :TYPE :TYPE? :RELative :RESet :RNUMber :RESet :ERRor? :CLEar :VERSion? :LOCal :REMote :RWLock Description Default parameter Ref For “single no-open” card, query number of banks. If not “single no-open” type, error -221 (settings conflict) results.
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15-24 SCPI Reference Tables Model 2700 Multimeter/Switch System User’s Manual Table 15-8 TRACe command summary Command TRACe|:DATA :CLEar [:IMMediate] :AUTO :AUTO? :FREE? :POINts :POINts? :NOTify Description Use TRACe or DATA as root command. Path to clear the buffer. Clear the buffer. Enable or disable buffer auto-clear. Query state of buffer auto-clear. Query bytes available and bytes in use. Specify size of buffer (2 to 55000). Query buffer size.
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Model 2700 Multimeter/Switch System User’s Manual SCPI Reference Tables 15-25 Table 15-9 Trigger command summary Command INITiate [:IMMediate] :CONTinuous :CONTinuous? Description Subsystem command path: Initiate one trigger cycle. Enable or disable continuous initiation. Query continuous initiation. ABORt Reset trigger system. TRIGger[:SEQuence[1]] Path to program Trigger Layer: :COUNt Set measure count (1 to 55000, or INFinity). :COUNt? Query measure count. :DELay Set delay (0 to 999999.
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15-26 SCPI Reference Tables Model 2700 Multimeter/Switch System User’s Manual Table 15-10 UNIT command summary Command UNIT :TEMPerature :TEMPerature? :VOLTage [:DC] [, ] :DB :REFerence :REFerence? [:DC]? [] :AC [, ] :DB :REFerence :REFerence? :AC? [] Description Select temperature units (C, CEL, F, FAR, or K). Query temperature units. Path to configure voltage units. Select DCV measurement units (V or DB).
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A Specifications Model 2700 Data Acquisition/Control System Model 7700 20-Channel Differential Multiplexer w/Automatic CJC
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A-2 Specifications Model 2700 Multimeter/Switch System User’s Manual
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Model 2700 Multimeter/Switch System User’s Manual Specifications A-3
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A-4 Specifications Model 2700 Multimeter/Switch System User’s Manual
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Model 2700 Multimeter/Switch System User’s Manual Specifications A-5
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A-6 Specifications Model 2700 Multimeter/Switch System User’s Manual
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Model 2700 Multimeter/Switch System User’s Manual Specifications A-7 Accuracy calculations The information below discusses how to calculate accuracy for both DC and AC characteristics. Calculating DC characteristics accuracy DC characteristics accuracy is calculated as follows: Accuracy = ±(ppm of reading + ppm of range) (ppm = parts per million, and 10ppm = 0.001%) As an example of how to calculate the actual reading limits, assume that you are measuring 5V on the 10V range.
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A-8 Specifications Model 2700 Multimeter/Switch System User’s Manual Calculating dBm characteristics accuracy As an example of how to calculate the actual reading limits for a 13dBm measurement with a reference impedance of 50Ω, assume an applied signal of 0.998815V. The relationship between voltage and dBm is as follows: 2 VIN ⁄ R REF 1mW dBm = 10 log ------------------------------From the previous example on calculating DC characteristics accuracy, it can be shown that a measurement of 0.
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Model 2700 Multimeter/Switch System User’s Manual Specifications A-9 Thus, the actual reading accuracy is 10mV ±36mV or 10.036mV to 9.964mV. Applying the voltage reading accuracy into the dB equation yields: dBm = 20 log 10.036mV -------------------------- = – 59.96879dB 10V dBm = 20 log 9.964mV ----------------------- = – 60.03133dB 10V Thus, the actual reading accuracy is -60dB + 0.031213dB to -60dB - 0.031326dB.
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A-10 Specifications Model 2700 Multimeter/Switch System User’s Manual Optimizing measurement speed The configurations listed below assume that the multimeter has had factory setups restored. DC voltage, DC current, and resistance: • Select 3Hdigits, 0.01 PLC, filter OFF, fixed range. AC voltage and AC current: • Select 3Hdigits, 0.01 PLC, filter OFF, fixed range. Temperature: • Select 3Hdigits, 0.01 PLC, filter OFF.
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B Model 7700 Connection Guide
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B-2 Model 7700 Connection Guide Model 2700 Multimeter/Switch System User’s Manual Card configuration — schematic Figure B-1 shows a simplified schematic diagram of the Model 7700 module. As shown, the Model 7700 has channels that are grouped into two banks of ten channels (twenty channels total). Backplane isolation is provided for each bank. Each bank also includes separate cold junction reference points.
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Model 2700 Multimeter/Switch System User’s Manual Model 7700 Connection Guide B-3 Figure B-1 Simplified schematic for Model 7700 Input HI LO Sense HI LO Cold Junction Ref x3 Channel 1 HI LO Channel 25 (See Note) Backplane Isolation (Channels 2–9) HI HI Input LO Channel 10 LO Channel 23 2-Pole (Open) 4-Pole (Closed) (See Note) Cold Junction Ref x3 Channel 11 Channel 24 (See Note) Backplane Isolation HI Sense LO HI LO To Model 2700 Backplane (Channels 12–19) HI Channel 20 LO AMPS 3A HI Channel
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B-4 Model 7700 Connection Guide Model 2700 Multimeter/Switch System User’s Manual Connections and wiring WARNING The following information is intended for qualified service personnel. Do not make or break switching module connections unless qualified to do so.
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Model 2700 Multimeter/Switch System User’s Manual Model 7700 Connection Guide Screw terminals Figure B-2 shows how to access the screw terminals on the Model 7700. Channel designations for the screw terminals are contained in Figure B-3.
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B-6 Model 7700 Connection Guide Model 2700 Multimeter/Switch System User’s Manual Figure B-3 Model 7700 screw terminal channel designations INPUT SENSE CH1 H L H L H L CH2 H L INPUT SENSE H L H L CH3 H L CH1 H L CH4 H L CH5 CH4 CH3 CH2 H L H L H L H L CH5 H L CH6 CH7 CH8 CH9 CH10 H L H L H L H L H L Cable Tie Holes CH6 H L CH7 H L CH8 CH9 CH10 H L H L H L INPUT (V, 2-WIRE) SENSE (OHMS, 4-WIRE) LO AMPS H L H L CH21 CH22 LO AMPS H L H L H L H L CH17 CH18 CH19 CH20 H L H L CH21 CH22 H L
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Model 2700 Multimeter/Switch System User’s Manual 3. Model 7700 Connection Guide Using a small flat-blade screwdriver, loosen terminal screws and install wires as desired. (Figure B-4 shows connections to channels 1 and 2.) Route wire along wire-path and secure with cable tie as shown. Fill in a copy of the connection log (Table B-1) and affix it to the module cover. Close and lock cover. 4. 5. 6.
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B-8 Model 7700 Connection Guide Model 2700 Multimeter/Switch System User’s Manual Typical connections The following examples show typical wiring connections for the following types of measurements: • • • • • Thermocouple connections, Figure B-5 Ω2-Wire and thermistor connections, Figure B-6 Ω4-Wire and RTD connections, Figure B-7 Current connections (AC or DC), Figure B-8 Voltage connections (AC or DC), Figure B-9 Figure B-5 Thermocouple connections HI Channel 1 LO (Channels 2-19) Thermocouple HI Cha
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Model 2700 Multimeter/Switch System User’s Manual Model 7700 Connection Guide Figure B-7 Ω4-Wire and RTD connections HI Resistor or 4-Wire RTD Channel 1 LO (Channels 2-9) HI Resistor or 4-Wire RTD Channel 10 LO HI Channel 11 LO (Channels 12-19) HI Channel 20 LO Figure B-8 Current connections (AC or DC) HI Channel 21 LO HI Channel 22 LO B-9
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B-10 Model 7700 Connection Guide Model 2700 Multimeter/Switch System User’s Manual Figure B-9 Voltage connections (DC or AC) DC Voltage AC Voltage HI + Channel 1 LO (Channels 2-19) HI + Channel 20 LO 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.
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Model 2700 Multimeter/Switch System User’s Manual Model 7700 Connection Guide Table B-1 Connection log Model 7700 Channel AMPS COM INPUT SENSE CH1 CH2 CH3 CH4 CH5 CH6 CH7 CH8 CH9 CH10 CH11 CH12 CH13 CH14 CH15 CH16 CH17 CH18 CH19 CH20 AMPS 21 AMPS 22 Color H L H L H L H L H L H L H L H L H L H L H L H L H L H L H L H L H L H L H L H L H L H L H L H L H L Description B-11
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B-12 Model 7700 Connection Guide Model 2700 Multimeter/Switch System User’s Manual
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C Status and Error Messages
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C-2 Status and Error Messages Model 2700 Multimeter/Switch System User’s Manual Table C-1 Status and error messages Number -440 -430 -420 -410 -363 -350 -330 -314 -315 -285 -284 -282 -281 -260 -241 -230 -225 -224 -223 -222 -221 -220 -215 -214 -213 -212 -211 -210 -202 -201 -200 -178 -171 -170 -168 -161 -160 -158 -154 -151 -150 Description Query unterminated after indefinite response Query deadlocked Query unterminated Query interrupted Input buffer overrun Queue overflow Self-test failed Save/recall memo
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Model 2700 Multimeter/Switch System User’s Manual Status and Error Messages Table C-1 (continued) Status and error messages Number Description Event -148 -144 -141 -140 -128 -124 -123 -121 -120 -114 -113 -112 -111 -110 -109 -108 -105 -104 -103 -102 -101 -100 Character data not allowed Character data too long Invalid character data Character data error Numeric data not allowed Too many digits Exponent too large Invalid character in number Numeric data error Header suffix out of range Undefined header P
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C-4 Status and Error Messages Model 2700 Multimeter/Switch System User’s Manual Table C-1 (continued) Status and error messages Number +101 +121 +122 +123 +124 +125 +126 +161 +171 +174 +180 +301 +302 +303 +304 +305 +306 +307 +308 +309 +310 +311 +312 +313 +314 Description Operation complete Device calibrating Device settling Device ranging Device sweeping Device measuring Device calculating Program running Waiting in trigger layer Re-entering the idle layer Filter settled Reading overflow Low limit 1 eve
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Model 2700 Multimeter/Switch System User’s Manual Status and Error Messages Table C-1 (continued) Status and error messages Number +400 +401 +402 +403 +404 +405 +406 +407 +408 +409 +410 +411 +412 +413 +414 +415 +416 +417 +418 +419 +420 +421 +422 +423 +424 +425 +426 +427 +428 +429 +430 +438 +439 +450 +451 +452 +453 +454 +455 Description Calibration messages: 10vdc zero error 100vdc zero error 10vdc full scale error -10vdc full scale error 100vdc full scale error -100vdc full scale error 1k 2-w zero error
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C-6 Status and Error Messages Model 2700 Multimeter/Switch System User’s Manual Table C-1 (continued) Status and error messages Number +456 +457 +458 +459 +460 +461 +462 +463 +464 +465 +466 +467 +468 +469 +470 +471 +472 +473 +474 +475 +476 +477 +478 +479 +480 +481 +482 +483 +484 +485 +486 +487 +488 +489 +490 +491 +492 +493 +494 +495 Description 1 vac zero error 1 vac full scale error 1 vac noise error 10 vac zero error 10 vac full scale error 10 vac noise error 100 vac zero error 100 vac full scale erro
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Model 2700 Multimeter/Switch System User’s Manual Status and Error Messages C-7 Table C-1 (continued) Status and error messages Number Description Event +496 +497 +498 +499 +500 +510 +511 +512 +513 +514 +515 +516 +517 +518 +519 +520 +521 1 4-w dckt Ioff zero error 1 4-w dckt Ion zero error 1 4-w dckt Ion full scale error 1V 10Hz frequency error Calibration data invalid Reading buffer data lost GPIB address lost Power-on state lost AC calibration data lost DC calibration data lost Calibration dates lo
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C-8 Status and Error Messages Model 2700 Multimeter/Switch System User’s Manual
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D Signal Processing Sequence and Data Flow
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D-2 Signal Processing Sequence and Data Flow Model 2700 Multimeter/Switch System User’s Manual Signal processing sequence Basic signal processing The signal is applied to the multimeter input via front panel input terminals or a switching module. When a channel is closed or scanned, the signal connected to that channel (or channel-pair for 4-wire measurements) is connected to the input. Figure D-1 is a flowchart that shows the basic processing sequence of an input signal.
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Model 2700 Multimeter/Switch System User’s Manual Signal Processing Sequence and Data Flow D-3 Signal processing using instrument features Figure D-2 shows the processing sequence for an input signal with various instrument features enabled. If a feature is not enabled, the reading simply falls through to the next enabled feature or to the display.
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D-4 Signal Processing Sequence and Data Flow Model 2700 Multimeter/Switch System User’s Manual OComp (offset-compensated ohms) The Model 2700 performs a normal ohms measurement by sourcing a known current (I), measuring the voltage (V), and then calculating the resistance (R = V/I). Offsetcompensated ohms cancels the effects of thermal EMFs which can adversely affect lowresistance measurements.
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Model 2700 Multimeter/Switch System User’s Manual Signal Processing Sequence and Data Flow D-5 Math Next in the signal processing sequence is a Math operation (mX+b, Percent, or Reciprocal). These math operations allow you to mathematically manipulate the reading (X) that is applied to this block in the flowchart. With one of the Math functions enabled, the math result is calculated as shown in Figure D-2. NOTE For details on Math operations, see “Math,” page 5-8.
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D-6 Signal Processing Sequence and Data Flow Model 2700 Multimeter/Switch System User’s Manual Signal processing using Ratio or Ch Avg With a switching module installed, the ratio or average of two channels can be calculated. Figure D-3 shows where Ratio or Ch Avg is calculated in the signal processing sequence.
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Model 2700 Multimeter/Switch System User’s Manual Signal Processing Sequence and Data Flow D-7 Data flow (remote operation) Remote operation can be used with triggering configured to perform a specified number of measurements and then stop. The various read commands (SENS:DATA?, FETCh?, READ?, MEAS?, CALC2:DATA?, TRACe:DATA?, and CALC1:DATA?) return the data array(s) acquired during the measurement cycle. Data flow for this triggering configuration is summarized by the block diagram shown in Figure D-4.
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D-8 Signal Processing Sequence and Data Flow NOTE Model 2700 Multimeter/Switch System User’s Manual For the following discussion, a “data array” is defined as the group of data elements that are included with each measured reading. Each data array includes the reading as well as the channel, reading number, units, timestamp, and limits result (see “FORMat:ELEMents ,” page 14-6, for details).
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Model 2700 Multimeter/Switch System User’s Manual Signal Processing Sequence and Data Flow D-9 [SENS[1]]:DATA[LATest]? [SENS[1]]:DATA:FRESh? These commands are used to return (read) the last processed data array stored in the sample buffer. [SENS[1]]:DATA[:LATest]? This command returns (reads) one data array. It returns the last processed data array stored in the sample buffer. If, for example, 10 data arrays are stored in the sample buffer, only the last (10th) data array is returned.
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D-10 Signal Processing Sequence and Data Flow Model 2700 Multimeter/Switch System User’s Manual FETCh? READ? MEASure? CALC[1]:DATA[LATest]? CALC[1]:DATA:FRESh? As shown in Figure D-4, these commands are used to read data arrays output from the CALC1 Math block. However, if there is no math function enabled, these commands read the data arrays in the sample buffer. NOTE For more information on FETCh?, READ?, and MEASure?, see Section 13, “SCPI Signal Oriented Measurement Commands.
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Model 2700 Multimeter/Switch System User’s Manual Signal Processing Sequence and Data Flow D-11 MEASure? The MEASure? command places the instrument in a “one-shot” measurement mode (which places one data array in the sample buffer) and then performs a READ?. With no math function enabled, the one data array in the sample buffer is read. With a math function enabled, the reading is the result of the math calculation.
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D-12 Signal Processing Sequence and Data Flow Model 2700 Multimeter/Switch System User’s Manual CALC2:IMM? CALC2:IMM CALC2:DATA? Statistical information (minimum, maximum, mean, standard deviation, and peak-to-peak) is available for the readings stored in the buffer (data store).
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Model 2700 Multimeter/Switch System User’s Manual Signal Processing Sequence and Data Flow D-13 Scanning For remote operation, scanning is normally performed with continuous initiation disabled (INIT:CONT OFF). The sample count (SAMP:COUNt) specifies the number of channels to scan and store in the buffers (sample buffer and data store), and the trigger count (TRIG:COUNt) specifies the number of scans to perform.
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D-14 Signal Processing Sequence and Data Flow Model 2700 Multimeter/Switch System User’s Manual
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E Measurement Considerations
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E-2 Measurement Considerations Model 2700 Multimeter/Switch System User’s Manual Measurement considerations Low-level voltage measurements made using the Model 2700 can be adversely affected by various types of noise or other unwanted signals that can make it very difficult to obtain accurate voltage readings. Some of the phenomena that can cause unwanted noise include thermoelectric effects (thermocouple action), source resistance noise, magnetic fields, and radio frequency interference.
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Model 2700 Multimeter/Switch System User’s Manual Measurement Considerations E-3 Thermoelectric generation Figure E-1 shows a representation of how thermal EMFs are generated. The test leads are made of the A material, while the source under test is the B material. The temperatures between the junctions are shown as T1 and T2.
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E-4 Measurement Considerations Model 2700 Multimeter/Switch System User’s Manual Minimizing thermal EMFs To minimize thermal EMFs, use only copper wires, lugs, and test leads for the entire test setup. Also, it is imperative that all connecting surfaces are kept clean and free of oxides. As noted in Table E-1, copper-to-copper oxide junctions can result in thermal EMFs as high as 1mV/°C. Even when low-thermal cables and connections are used, thermal EMFs can still be a problem in some cases.
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Model 2700 Multimeter/Switch System User’s Manual Measurement Considerations E-5 Source resistance noise Noise present in the source resistance is often the limiting factor in the ultimate resolution and accuracy of Model 2700 measurements. The following paragraphs discuss the generation of Johnson noise as well as ways to minimize such noise.
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E-6 Measurement Considerations Model 2700 Multimeter/Switch System User’s Manual Magnetic fields When a conductor loop cuts through magnetic lines of force, a very small current is generated. This phenomenon will frequently cause unwanted signals to occur in the test leads of a test system. If the conductor has sufficient length or cross-sectional area, even weak magnetic fields such as those of the earth can create sufficient signals to affect lowlevel measurements.
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Model 2700 Multimeter/Switch System User’s Manual Measurement Considerations E-7 path such as 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 develops a small but undesirable voltage between the LO terminals of the two instruments. This voltage will be added to the source voltage, affecting the accuracy of the measurement.
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E-8 Measurement Considerations Model 2700 Multimeter/Switch System User’s Manual Shielding WARNING Do not float input LO more than 30V rms, 42.4V peak above earth ground with an exposed shield connected to input LO. To avoid a possible shock hazard, surround the LO shield with a second safety shield that is insulated from the inner shield. Connect this safety shield to safety earth ground using #18 AWG minimum wire before use.
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Model 2700 Multimeter/Switch System User’s Manual Measurement Considerations E-9 Meter loading Loading of the voltage source by the Model 2700 becomes a consideration for high source resistance values. As the source resistance increases, the error caused by meter loading increases. Figure E-5 shows the method used to determine the percent error due to meter loading.
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E-10 Measurement Considerations Model 2700 Multimeter/Switch System User’s Manual
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F Temperature Equations • Thermocouple equation — Documents the ITS-90 inverse function polynomial and the coefficients to calculate thermocouple temperature. • Thermistor equation — Documents the Steinhart-Hart equation which is used to calculate thermistor temperature. • RTD equation — Documents the Callendar-Van Dusen equation which is used to calculate the temperature vs. resistance readings listed in the RTD reference tables.
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F-2 Temperature Equations Model 2700 Multimeter/Switch System User’s Manual Thermocouple equation The Model 2700 uses the ITS-90 inverse function coefficients for the polynomial to calculate thermocouple temperature. The Model 2700 measures the thermocouple voltage, and then calculates temperature (in °C) as follows: t90 = c0 + c1E + c2E2 + c3E3 ... ciEi where: t90 is the calculated temperature in °C. c0, c1, c2, c3 ... ci are the coefficients for the thermocouple type.
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Model 2700 Multimeter/Switch System User’s Manual Temperature Equations F-3 Table F-2 Type E inverse function polynomial -200°C to 0°C (-8,825µV to 0µV) c0 = c1 = c2 = c3 = c4 = c5 = c6 = c7 = c8 = c9 = Error: 0.0 1.697 728 8 × -4.351 497 0 × -1.585 969 7 × -9.250 287 1 × -2.608 431 4 × -4.136 019 9 × -3.403 403 0 × -1.156 486 0 × 0°C to 1,000°C (0µV to 76,373µV) 0.0 1.705 703 5 × 10-2 -2.330 175 9 × 10-7 6.543 558 5 × 10-12 -7.356 274 9 × 10-17 -1.789 600 1 × 10-21 8.403 616 5 × 10-26 -1.
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F-4 Temperature Equations Model 2700 Multimeter/Switch System User’s Manual Table F-4 Type K inverse function polynomial -200°C to 0°C (-5,891µV to 0µV) c0 = c1 = c2 = c3 = c4 = c5 = c6 = c7 = c8 = c9 = Error: 0.0 2.517 346 2 × -1.166 287 8 × -1.083 363 8 × -8.977 354 0 × -3.734 237 7 × -8.663 264 3 × -1.045 059 8 × -5.192 057 7 × 10-2 10-6 10-9 10-13 10-16 10-20 10-23 10-28 0.04°C to -0.02°C 0°C to 500°C (0µV to 20,644µV) 0.0 2.508 355 2 × 10-2 7.860 106 2 × 10-8 -2.503 131 2 × 10-10 8.
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Model 2700 Multimeter/Switch System User’s Manual Temperature Equations F-5 Table F-6 Type R inverse function polynomial -50°C to 250°C (-226µV to 1,923µV) c0 = c1 = c2 = c3 = c4 = c5 = c6 = c7 = c8 = c9 = c10 = Error: 250°C to 1,200°C (1,923µV to 13,228µV) 0.0 1.889 138 0 × 10-1 -9.383 529 0 × 10-5 1.306 861 9 × 10-7 -2.270 358 0 × 10-10 3.514 565 9 × 10-13 -3.895 390 0 × 10-16 2.823 947 1 × 10-19 -1.260 728 1 × 10-22 3.135 361 1 × 10-26 -3.318 776 9 × 10-30 0.02°C to -0.02°C 1.334 584 505 × 1.
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F-6 Temperature Equations Model 2700 Multimeter/Switch System User’s Manual Table F-8 Type T inverse function polynomial -200°C to 0°C (-5,603µV to 0µV) c0 = c1 = c2 = c3 = c4 = c5 = c6 = c7 = Error: 0.0 2.594 919 2 × 10-2 -2.131 696 7 × 10-7 7.901 869 2 × 10-10 4.252 777 7 × 10-13 1.330 447 3 × 10-16 2.024 144 6 × 10-20 1.266 817 1 × 10-24 0.04°C to -0.02°C 0°C to 400°C (0µV to 20,872µV) 0.0 2.592 800 × -7.602 961 × 4.637 791 × -2.165 394 × 6.048 144 × -7.
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Model 2700 Multimeter/Switch System User’s Manual Temperature Equations F-7 Selecting a thermistor — The thermistor manufacturers specified curve fitting values (A, B, and C) may not be exactly the same as the ones used by the Model 2700. If they are not exactly the same, perform the following steps to select a thermistor to use with the Model 2700: NOTE 1. 2. 3. 4.
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F-8 Temperature Equations Model 2700 Multimeter/Switch System User’s Manual RTD equations The temperature vs. resistance readings listed in the RTD reference tables are calculated using the Callendar-Van Dusen equation. There are two equations based on different temperature ranges. There is an equation for the -200° to 0°C range and one for the 0° to 630°C range.
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Model 2700 Multimeter/Switch System User’s Manual Temperature Equations F-9 RTD parameters for equations The RTD parameters for the Callendar-Van Dusen equations are listed in Table F-10. Table F-10 RTD parameters Type Standard Alpha Beta Delta Ω at 0°C PT100 D100 F100 PT385 PT3916 ITS-90 ITS-90 ITS-90 IPTS-68 IPTS-68 0.003850 0.003920 0.003900 0.003850 0.003916 0.10863 0.10630 0.11000 0.11100 0.11600 1.49990 1.49710 1.49589 1.50700 1.
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F-10 Temperature Equations Model 2700 Multimeter/Switch System User’s Manual Example 2 Calculate the resistance of a D100 RTD at -100°C (T). The following R0 (Ω at 0°C), alpha, beta, and delta values are used for the D100 RTD (Table F-10): T = -100°C R0 (Ω at 0°C) = 100Ω alpha = 0.003920 beta = 0.10630 delta = 1.49710 Using the above alpha and delta values, A and B are calculated as follows: A = 0.003920 [1 + (1.49710/100)] = 0.003920 (1.014971) = 0.003978686 B = -1 (0.003920)(1.49710)(1e-4) = -1 (0.
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G IEEE-488 Bus Overview
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G-2 IEEE-488 Bus Overview Model 2700 Multimeter/Switch System User’s Manual Introduction The IEEE-488 bus is a communication system between two or more electronic devices. A device can be either an instrument or a computer. When a computer is used on the bus, it serves as a supervisor of the communication exchange between all the devices and is known as the controller. Supervision by the controller consists of determining which device will talk and which device will listen.
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Model 2700 Multimeter/Switch System User’s Manual IEEE-488 Bus Overview Figure G-1 IEEE-488 bus configuration To Other Devices Device 1 able to talk, listen, and control (computer) Device 2 able to talk and listen 2700 Device 3 only able to listen (printer) Data Bus Data Byte Transfer Control General Interface Management Device 4 only able to talk DIO 1 8 Data (8 Lines) DAV NRFD NDAC Handshake IFC ATN SRQ REN EOI Bus Management G-3
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G-4 IEEE-488 Bus Overview Model 2700 Multimeter/Switch System User’s Manual There are two categories of controllers: system controller and basic controller. Both are able to control other instruments, but only the system controller has the absolute authority in the system. In a system with more than one controller, only one controller may be active at any given time. Certain protocol is used to pass control from one controller to another.
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Model 2700 Multimeter/Switch System User’s Manual IEEE-488 Bus Overview G-5 Bus management lines The five bus management lines help to ensure proper interface control and management. These lines are used to send the uniline commands. ATN (Attention) — The ATN state determines how information on the data bus is to be interpreted. IFC (Interface Clear) — The IFC line controls clearing of instruments from the bus.
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G-6 IEEE-488 Bus Overview Model 2700 Multimeter/Switch System User’s Manual Once all NDAC and NRFD are properly set, the source sets DAV low, indicating to accepting devices that the byte on the data lines is now valid. NRFD will then go low, and NDAC will go high once all devices have accepted the data. Each device will release NDAC at its own rate, but NDAC will not be released to go high until all devices have accepted the data byte.
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Model 2700 Multimeter/Switch System User’s Manual IEEE-488 Bus Overview G-7 Table G-1 IEEE-488 bus command summary Command type Command State of ATN line Comments Uniline REN (Remote Enable) EOI IFC (Interface Clear) ATN (Attention) SRQ X X X Low X Set up devices for remote operation. Marks end of transmission. Clears interface. Defines data bus contents. Controlled by external device.
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G-8 IEEE-488 Bus Overview Model 2700 Multimeter/Switch System User’s Manual Uniline commands ATN, IFC, and REN are asserted only by the controller. SRQ is asserted by an external device. EOI may be asserted either by the controller or other devices depending on the direction of data transfer. The following is a description of each command. Each command is sent by setting the corresponding bus line true. REN (Remote Enable) — REN is sent to set up instruments on the bus for remote operation.
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Model 2700 Multimeter/Switch System User’s Manual IEEE-488 Bus Overview G-9 Addressed multiline commands Addressed commands are multiline commands that must be preceded by the device listen address before that instrument will respond to the command in question. Note that only the addressed device will respond to these commands. Both the commands and the address preceding it are sent with ATN true.
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G-10 IEEE-488 Bus Overview Model 2700 Multimeter/Switch System User’s Manual Common commands Common commands are commands that are common to all devices on the bus. These commands are designated and defined by the IEEE-488.2 standard. Generally, these commands are sent as one or more ASCII characters that tell the device to perform a common operation, such as reset. The IEEE-488 bus treats these commands as data in that ATN is false when the commands are transmitted.
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D2 0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1 D3 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 D1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 D0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Column Row GET TCT* SDC PPC* GTL 0 (B) Command ADDRESSED COMMAND GROUP (ACG) NUL SOH STX ETX EOT ENQ ACK BEL BS HT LF VT FF CR SO SI 0 (A) X 0 0 0 SPE SPD DCL PPU* LLO 1 (B) UNIVERSAL COMMAND GROUP (UCG) DLE DC1 DC2 DC3 DC4 NAK SYN ETB CAN EM SUB ESC FS GS RS US 1 (A) X 0 0 1 Command Primary Address + , _
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G-12 IEEE-488 Bus Overview Model 2700 Multimeter/Switch System User’s Manual Typical command sequences For the various multiline commands, a specific bus sequence must take place to properly send the command. In particular, the correct listen address must be sent to the instrument before it will respond to addressed commands. Table G-3 lists a typical bus sequence for sending the addressed multiline commands. In this instance, the SDC command is being sent to the instrument.
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Model 2700 Multimeter/Switch System User’s Manual IEEE-488 Bus Overview IEEE command groups Command groups supported by the Model 2700 are listed in Table G-5. Common commands and SCPI commands are not included in this list.
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G-14 IEEE-488 Bus Overview Model 2700 Multimeter/Switch System User’s Manual Interface function codes The interface function codes, which are part of the IEEE-488 standards, define an instrument’s ability to support various interface functions and should not be confused with programming commands found elsewhere in this manual. The interface function codes for the Model 2700 are listed in Table G-6.
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Model 2700 Multimeter/Switch System User’s Manual IEEE-488 Bus Overview G-15 PP (Parallel Poll Function) — The instrument does not have parallel polling capabilities (PP0). DC (Device Clear Function) — DC1 defines the ability of the instrument to be cleared (initialized). DT (Device Trigger Function) — DTI defines the ability of the Model 2700 to have readings triggered. C (Controller Function) — The instrument does not have controller capabilities (C0).
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G-16 IEEE-488 Bus Overview Model 2700 Multimeter/Switch System User’s Manual
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H KE2700 Instrument Driver Examples
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H-2 KE2700 Instrument Driver Examples Model 2700 Multimeter/Switch System User’s Manual Introduction An IVI style Instrument Driver is provided with the Models 2700, 2701, and 2750. The driver supports programming in LabView, LabWindows CVI, Visual Basic, and C, Test examples provided by the KE2700 Instrument Driver are listed in Table H-1 and Table H-2. Some of the examples demonstrate the simple command sequence examples that are used throughout this manual.
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Model 2700 Multimeter/Switch System User’s Manual KE2700 Instrument Driver Examples H-3 Table H-1 Visual Basic and CVI (C) examples Name Manual Reference Brief Description Advance1 None Use Case 1 — 40-channel scan using 7708 module: • 30 channels DCV (10V range). • 10 channels type T thermocouple temperature. • Measurement speed (rate) – 1 plc. • Filter – Disabled (no filtering). • Buffer – Store 160 reading strings. Buffer elements include reading, channel #, and real time clock.
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H-4 KE2700 Instrument Driver Examples Model 2700 Multimeter/Switch System User’s Manual Table H-1 (continued) Visual Basic and CVI (C) examples Name Advance4 Manual Reference None Brief Description Use Case 4 — Two scans using 7708 module: • 40 channel DCV scan (1V range). Configuration saved in User Setup 1. • 20 channel Ω4 scan. Configuration saved in User Setup 2. • Models 2700 and 2701 – 100Ω range. • Model 2750 – 10Ω range, dry-circuit ohms enabled. • Setup 1 or Setup 2 recalled to perform scan.
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Model 2700 Multimeter/Switch System User’s Manual KE2700 Instrument Driver Examples H-5 Table H-1 (continued) Visual Basic and CVI (C) examples Name Advance6 Manual Reference None Brief Description Use Case 6 — Scan 160 channels using 7703 module (see NOTE): • Type K thermocouple (TC) temperature measurements. • Reference junction – Simulated. • Measurement speed (rate) – 0.01 plc. • Filter – Disabled (no filtering). • Buffer – Store 160 reading strings. Buffer elements include reading and channel #.
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H-6 KE2700 Instrument Driver Examples Model 2700 Multimeter/Switch System User’s Manual Table H-1 (continued) Visual Basic and CVI (C) examples Name Advance8 Manual Reference None Brief Description Use Case 8 — 7706 module in slot 1 and 7702 module in slot 2: • 7706 module: • Output analog output values to analog output channels. • Output digital output values to digital output channels. • 7702 module: • Scan 120 DCV channels. • Measurement speed (rate) – 1 plc. • Filter – Disabled (no filtering).
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Model 2700 Multimeter/Switch System User’s Manual KE2700 Instrument Driver Examples H-7 Table H-1 (continued) Visual Basic and CVI (C) examples Name Manual Reference Brief Description MultiRange Page 4-5 (Ex. 1 & 2) Demonstrates various range and function settings. Ohmm Page 3-55 (Ex. 2) Demonstrates measuring offset compensated ohms in one-shot trigger mode. Percent Page 5-15 (Ex. 2) Demonstrates percent calculation. PollSQR Page 11-9 (Prog Ex.
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H-8 KE2700 Instrument Driver Examples Model 2700 Multimeter/Switch System User’s Manual Table H-1 (continued) Visual Basic and CVI (C) examples Name Manual Reference Brief Description Simple2 None Use Case 2 — 40-channel scan using 7708 module: • 30 channels DCV (15 on 100mV range, 15 on 10V range). • 9 channels ACV (1V range). • 1 channel 4-wire RTD temperature. • Measurement speed (rate) – 1 plc. • Filter – Disabled (no filtering). • Buffer – Store 120 reading strings.
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Model 2700 Multimeter/Switch System User’s Manual KE2700 Instrument Driver Examples H-9 Table H-1 (continued) Visual Basic and CVI (C) examples Name Manual Reference Brief Description Simple4 None Use Case 4 — Two scans using 7708 module: • 40 channel DCV scan (1V range). Configuration saved in User Setup 1. • 20 channel Ω4 scan. Configuration saved in User Setup 2. • Models 2700 and 2701 – 100Ω range. • Model 2750 – 10Ω range, dry-circuit ohms enabled. • Setup 1 or Setup 2 recalled to perform scan.
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H-10 KE2700 Instrument Driver Examples Model 2700 Multimeter/Switch System User’s Manual Table H-1 (continued) Visual Basic and CVI (C) examples Name Simple6 Manual Reference None Brief Description Use Case 6 — Scan 160 channels using 7703 module (see NOTE): • Type K thermocouple (TC) temperature measurements. • Reference junction – Simulated. • Measurement speed (rate) – 0.01 plc. • Filter – Disabled (no filtering). • Buffer – Store 160 reading strings. Buffer elements include reading only.
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Model 2700 Multimeter/Switch System User’s Manual KE2700 Instrument Driver Examples H-11 Table H-1 (continued) Visual Basic and CVI (C) examples Name Manual Reference Brief Description Simple8 None Use Case 8 — 7706 module in slot 1 and 7702 module in slot 2: • 7706 module: • Output analog output values to analog output channels. • Output digital output values to digital output channels. • 7702 module: • Scan 120 DCV channels. • Measurement speed (rate) – 1 plc. • Filter – Disabled (no filtering).
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H-12 KE2700 Instrument Driver Examples Model 2700 Multimeter/Switch System User’s Manual LabVIEW examples Table H-2 lists the LabVIEW examples and “Use Cases” that are provided with the KE2700 Instrument Driver. LabVIEW examples are provided in the file: Examples.llb. Use cases are provided in the file: Use Cases.llb. By default, these are installed in the Program Files\National Instruments\LabView X\instr.lib\KE2700 directory.
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Model 2700 Multimeter/Switch System User’s Manual KE2700 Instrument Driver Examples H-13 Table H-2 (continued) LabVIEW examples Name Advance2 Manual Reference None Brief Description Use Case 2 — 40-channel scan using 7708 module: • 30 channels DCV (15 on 100mV range, 15 on 10V range). • 9 channels ACV (1V range). • 1 channel 4-wire RTD temperature. • Measurement speed (rate) – 1 plc. • Filter – Disabled (no filtering). • Buffer – Store 160 reading strings. Buffer elements include reading only.
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H-14 KE2700 Instrument Driver Examples Model 2700 Multimeter/Switch System User’s Manual Table H-2 (continued) LabVIEW examples Name Advance4 Manual Reference None Brief Description Use Case 4 — Two scans using 7708 module: • 40 channel DCV scan (1V range). Configuration saved in User Setup 1. • 20 channel Ω4 scan. Configuration saved in User Setup 2. • Models 2700 and 2701 – 100Ω range. • Model 2750 – 10Ω range, dry-circuit ohms enabled. • Setup 1 or Setup 2 recalled to perform scan.
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Model 2700 Multimeter/Switch System User’s Manual KE2700 Instrument Driver Examples H-15 Table H-2 (continued) LabVIEW examples Name Advance6 Manual Reference None Brief Description Use Case 6 — Scan 160 channels using 7703 module (see NOTE): • Type K thermocouple (TC) temperature measurements. • Reference junction – Simulated. • Measurement speed (rate) – 0.01 plc. • Filter – Disabled (no filtering). • Buffer – Store 160 reading strings. Buffer elements include reading and channel #.
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H-16 KE2700 Instrument Driver Examples Model 2700 Multimeter/Switch System User’s Manual Table H-2 (continued) LabVIEW examples Name Advance8 Manual Reference None Brief Description Use Case 8 — 7706 module in slot 1 and 7702 module in slot 2: • 7706 module: • Output analog output values to analog output channels. • Output digital output values to digital output channels. • 7702 module: • Scan 120 DCV channels. • Measurement speed (rate) – 1 plc. • Filter – Disabled (no filtering).
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Model 2700 Multimeter/Switch System User’s Manual KE2700 Instrument Driver Examples H-17 Table H-2 (continued) LabVIEW examples Name Manual Reference Brief Description Simple3 None Use Case 3 — Two scans using 7708 module: • 40 channel DCV (1V range) scan. • 20 channel Ω4 scan: • Models 2700 and 2701 – 100Ω range. • Model 2750 – 10Ω range, dry-circuit ohms enabled. • Measurement speed (rate) – 0.1 plc. • DCV input divider – Enabled (10MΩ input impedance). • Filter – Disabled (no filtering).
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H-18 KE2700 Instrument Driver Examples Model 2700 Multimeter/Switch System User’s Manual Table H-2 (continued) LabVIEW examples Name Manual Reference Brief Description Simple5 None Use Case 5 — 32-channel scan using 7701 module. • Common-side 4-wire ohms measurements (CSIDe mode). • Dry-circuit ohms option for Model 2750. • Install jumpers to connect Input Hi and Sense Hi directly to DUT (common-side bus). • Install jumpers to connect channel 35 to Sense Lo and Input Lo.
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Model 2700 Multimeter/Switch System User’s Manual KE2700 Instrument Driver Examples H-19 Table H-2 (continued) LabVIEW examples Name Manual Reference Brief Description Simple7 None Use Case 7 — Ten 40-channel scans using 7702 module: • Channel 1 uses an external reference junction. • Measurement speed (rate) – 1 plc. • Filter – Repeat, 25 readings. • Channels 2 through 40 are connected to type K thermocouples. • Measurement speed (rate) – 1 plc. • Filter – Disabled (no filtering).
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H-20 KE2700 Instrument Driver Examples Model 2700 Multimeter/Switch System User’s Manual
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Index Overview 3-2 Baud rate 10-18 Beeper control 8-7 Buffer 6-1, 7-27 Auto clear 6-2 Clear 6-12 Commands 6-9 CALCulate2:DATA? 6-15 CALCulate2:FORMat 6-15 CALCulate2:IMMediate 6-15 CALCulate2:IMMediate? 6-15 CALCulate2:STATe 6-15 FORMat:ELEMents 6-14 SYSTem:DATE 6-10 SYSTem:TIME 6-10 SYSTem:TSTamp:TYPE 6-11 TRACe:CLEar 6-11 TRACe:CLEar:AUTO 6-11 TRACe:DATA:SELected? , 6-13 TRACe:DATA? 6-12 TRACe:FEED 6-12 TRACe:FEED:CONTrol 6-12 TRACe:FREE? 6-11 TRACe:NEXT? 6-13 TRACe:NOTify 6-13 TRACe:POINt
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Delay 5-19 Enabling/disabling 5-19 Programming examples 5-20 Remote programming 5-19 Scanning 5-18 Channel list parameter () 3-6 Channels Assignments 2-5, 7-3 Auto channel configuration 7-20 Average see Channel average Closing and opening 1-29, 2-1 Monitor 7-18 Multiple see Multiple channels Numbering 2-5 Setup 7-27 Setup considerations 7-11 System see System channel CLOSE key 2-10, 2-18 CLOSE:MULTI 2-10 CLOSE:SINGLE 2-10 Color codes Thermocouple wires 3-38 Commands Address G-9 Addressed multiline G-
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Current measurements (DCI and ACI) 3-17 AMPS fuse replacement (front panel AMPS input) 3-19 Amps measurement procedure 3-18 Connections 3-17 Front panel inputs 3-17 Model 7700 switching module 3-18 CVI (C) examples H-2 Scanning 4-6 Setting 4-7 Display 1-18 Annunciators 1-12 Commands 1-18 DISPlay:ENABle 1-19 DISPlay:TEXT:DATA 1-19 DISPlay:TEXT:STATe 1-19 Programming example 1-19 Remote programming 1-18 DMM measurements 1-27 Dual independent multiplexers 2-24 Dual multiplexer application 2-25 DUT test system
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With BNC connections 8-13 REN (remote enable) 10-8 SDC (selective device clear) 10-9 SPE, SPD (serial polling) 10-9 General information 1-2 Getting started 1-1 GPIB Configuration G-3 Connections 10-5 Description G-2 Front panel 10-10 Overview G-1 Selecting 10-4 Setup 10-4 Standards 10-4 Status indicators 10-10 Ground loops E-6 F Features Model 2700 1-6 Filter 4-13 *RST disables filter 4-18 *RST disables filter state to off 4-21 Characteristics 4-13 Commands 4-20 Control and configuration 4-18 Count 4-14 E
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J Johnson noise equation E-5 K KE2700 Instrument Driver H-1 Keyclick 1-18 Remote programming 1-18 Key-press codes 14-9 Keys CLOSE 2-10, 2-18 FILTER 4-18 Function 1-11 LOCAL 10-11 OPEN 2-11, 2-19 Operation 1-11 Range 1-12 RATE 4-8 Special 1-11 L LabVIEW examples H-12 Limits 9-2 Basic operation 9-4 Beeper settings 9-4 Commands 9-12 Default 9-2 Enabling/disabling 9-4 Programming example 9-14 Remote programming 9-12 Scanning 9-4 Setting 9-4 Line cycle synchronization see LSYNC Line frequency 1-16 Line power c
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Voltage connections (DC or AC) B-10 Wire dressing B-7 Wiring procedure B-6 Monitor channel 7-18 Monitor scan example 7-37 Multiple channels Control commands 2-20 Controlling 2-17 Operation 2-16 Anomalies 2-22 mX+b (math function) 5-9 Configuration 5-9 Rel 5-10 Setting units 5-14 N Noise Johnson noise equation E-5 Lowest settings 4-8 Source resistance E-5 vs.
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Rear panel Summary 1-14 Reciprocal (1/X) (math function) 5-11 Configuration 5-11 Reference junctions 3-34 External 3-35 Internal 3-34 Simulated 3-34 Registers Bit descriptions 11-12 Clearing 11-4 Condition 11-18 Event 11-18 Event enable 11-19 Measurement event 11-15 Operation event 11-14 Programming enable registers 11-5 Questionable event 11-17 Reading 11-6 Service request enable 11-8 Standard event 11-12 Status byte and SRQ see Status byte and service request (SRQ) Status byte register 11-7 Status registe
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Auto scan 7-21 Basic scan 7-22 Buffer 7-22 Configuration 7-10 dB 5-21 Digital outputs 9-12 Digits 4-6 Examples 7-33 External trigger scan example 7-33 Filter 4-19 Fundamentals 7-2 Limits 9-4 Manual/external trigger scan 7-23 Math 5-12 Monitor scan 7-36 Monitor scan (analog trigger) 7-24 Operation 7-22 Process 7-4 Range 4-3 Rate and bandwidth 4-10 Ratio and channel average 5-18 Relative 5-3 Remote programming 7-26 Remote programming example 7-32 Reset 7-13 Resume scan after power-up 7-21 Sequential and non-s
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4-wire RTDs 3-36 Configuration 3-40 Connections 3-36 Procedure 3-43 Thermistors 3-35 Thermocouples 3-33 Terminator 10-19 Tests Continuity see Continuity testing Thermal EMFs 3-15 Minimizing E-4 Thermistors 3-35 Connections 3-39 Equation F-6 Temperature measurement configuration 3-41 Thermocouples 3-33 Color codes 3-38 Connections 3-36 Equation F-2 Open thermocouple detection 3-35 Reference junctions see Reference junctions Temperature measurement configuration 3-40 Thermoelectric Coefficients E-2 Generation
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7.5X9BackCovr 12-06.qxd 1/10/07 2:45 PM Page 1 Specifications are subject to change without notice. All Keithley trademarks and trade names are the property of Keithley Instruments, Inc. All 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 Road • Cleveland, Ohio 44139 • 440-248-0400 • Fax: 440-248-6168 • 1-888-KEITHLEY • www.keithley.