HP HP 34970A - Manual

Display Annunciators To review the display annunciators, hold down the key as you turn on the instrument. SCAN MON VIEWCONFIG ADRS RMTERROREXTONCEMEMLASTMINMAXSHIFT4WOC Scan is in progress or enabled. Press and hold again to turn off. Monitor mode is enabled. Press again to turn off. Scanned reading...

The Rear Panel at a Glance WARNING For protection from electrical shock, the power cord ground must not bedefeated. If only a two-contact electrical outlet is available, connect theinstrument’s chassis ground screw (see above) to a good earth ground. 1 Slot Identifier (100, 200, 300) 2 Ext Trig Inpu...

HP BenchLink Data Logger Software at a Glance HP BenchLink Data Logger is a Windows-based application designed to make it easy to use the HP 34970A with your PC for gathering and analyzing measurements. Use the software to set up your test, acquireand archive measurement data, and perform real-time ...

The Plug-In Modules at a Glance For complete specifications on each plug-in module, refer to the modulesections in chapter 9. HP 34901A 20-Channel Armature Multiplexer • 20 channels of 300 V switching • Two channels for DC or AC current measurements (100 nA to 1A) • Built-in thermocouple reference j...

HP 34903A 20-Channel Actuator / General-Purpose Switch • 300 V, 1 A actuation and switching • SPDT (Form C) latching relays • Breadboard area for custom circuits • For detailed information and a module diagram, see page 168. Use this module for those applications that require high-integritycontacts ...

HP 34907A Multifunction Module • Two 8-bit Digital Input/Output ports, 400 mA sink, 42 V open collector • 100 kHz Totalize input with 1 Vpp sensitivity • Two ± 12 V Calibrated Analog Outputs • For detailed information and module block diagrams, see page 174. Use this module to sense status and contr...

In This Book Quick Start Chapter 1 helps you get familiar with a few of the instrument’s front-panel features. This chapter also shows how toinstall the HP BenchLink Data Logger software. Front-Panel Overview Chapter 2 introduces you to the front-panel menus and describes some of the instrument’s me...

Contents Chapter 1 Quick Start To Prepare the Instrument for Use 17Installing HP BenchLink Data Logger Software 18 To Connect Wiring to a Module 20To Set the Time and Date 22To Configure a Channel for Scanning 23To Copy a Channel Configuration 25To Close a Channel 26If the Instrument Does Not Turn O...

Chapter 4 Features and Functions SCPI Language Conventions 73Scanning 74Single-Channel Monitoring 93Scanning With External Instruments 95General Measurement Configuration 98Temperature Measurement Configuration 106Voltage Measurement Configuration 113Resistance Measurement Configuration 115Current M...

Quick Start One of the first things you will want to do with your instrument is tobecome acquainted with the front panel. We have written the exercisesin this chapter to prepare the instrument for use and help you getfamiliar with some of its front-panel operations. The front panel has several group...

To Prepare the Instrument for Use 1 Check the list of supplied items. Verify that you have received the following items with your instrument.If anything is missing, contact your nearest Hewlett-Packard Sales Office. One power cord. This User’s Guide . One Service Guide . One Quick Reference Guide . ...

Installing HP BenchLink Data Logger Software If you ordered the HP 34970A with the internal DMM , then the HP BenchLink Data Logger software is included. The software isshipped on one CD-ROM , but includes a utility to build installation floppy disks. To install the software on your PC , you will ne...

Creating Installation Floppy Disks You have the option to create an installation on floppy disks from the CD-ROM installation utility. This utility is provided so that you can install HP BenchLink Data Logger on a computer that does not have a CD-ROM drive. Note : You will need a total of five (5) f...

To Connect Wiring to a Module 6 mm 20 AWG Typical Channel Number: Slot Channel 5 Install the module into mainframe. Wiring Hints... • For detailed information on each module, refer to the section starting on page 163. • To reduce wear on the internal DMM relays, wire like functions on adjacent chann...

DC Voltage / AC Voltage / Frequency Thermocouple Thermocouple Types: B, E, J, K, N, R, S, TSee page 351 for thermocouple color codes. Ranges: 100 mV, 1 V, 10 V, 100 V, 300 V 4-Wire Ohms / RTD 2-Wire Ohms / RTD / Thermistor Ranges: 100, 1 k, 10 k, 100 k, 1 M, 10 M, 100 M Ω RTD Types: 0.00385, 0.00391...

To Set the Time and Date All readings during a scan are automatically time stamped and storedin non-volatile memory. In addition, alarm data is time stamped andstored in a separate non-volatile memory queue. 1 Set the time of day. Use and to select the field to modify and turn the knob to change the...

To Configure a Channel for Scanning Any channel that can be “read” by the instrument can also be includedin a scan. This includes readings on multiplexer channels, a read of adigital port, or a read of the count on a totalizer channel. Automatedscanning is not allowed with the RF multiplexer, matrix...

Note : Press to sequentially step through the scan list and take a measurement on each channel (readings are not stored in memory).This is an easy way to verify your wiring connections before initiatingthe scan. 3 Run the scan and store the readings in non-volatile memory. The instrument automatical...

To Copy a Channel Configuration After configuring a channel to be included in the scan list, you cancopy that same configuration to other channels in the instrument(including digital channels on the multifunction module). This featuremakes it easy to configure several channels for the same measureme...

To Close a Channel On the multiplexer and switch modules, you can close and open individualrelays on the module. However, note that if you have already configuredany multiplexer channels for scanning, you cannot independently closeand open individual relays on that module. 1 Select the channel. Turn...

If the Instrument Does Not Turn On Use the following steps to help solve problems you might encounterwhen turning on the instrument. If you need more help, refer to the HP 34970A Service Guide for instructions on returning the instrument to Hewlett-Packard for service. 1 Verify that there is ac powe...

1 Remove the power cord . Remove the fuse-holder assembly from the rear panel. 2 Remove the line-voltage selector from the assembly. 3 Rotate the line-voltage selector until the correct voltage appears in the window. 4 Replace the fuse-holder assembly in the rear panel. Verify that the correct line ...

To Adjust the Carrying Handle To adjust the position, grasp the handle by the sides and pull outward . Then, rotate the handle to the desired position. Bench-top viewing positions Carrying position 1 Chapter 1 Quick StartTo Adjust the Carrying Handle 29

To Rack Mount the Instrument You can mount the instrument in a standard 19-inch rack cabinet usingone of three optional kits available. Instructions and mountinghardware are included with each rack-mounting kit. Any HP System II instrument of the same size can be rack-mounted beside the HP 34970A. N...

To rack mount two instruments side-by-side, order lock-link kit 5061-9694 and flange kit 5063-9212. Be sure to use the support rails inside the rack cabinet. To install one or two instruments in a sliding support shelf, order shelf 5063-9255, and slide kit 1494-0015 (for a single instrument, also or...

Front-Panel Menu Reference This section gives an overview of the front-panel menus. The menus aredesigned to automatically guide you through all parameters required toconfigure a particular function or operation. The remainder of thischapter shows examples of using the front-panel menus. Configure t...

To Monitor a Single Channel You can use the Monitor function to continuously take readings on a single channel, even during a scan. This feature is useful for troubleshooting yoursystem before a test or for watching an important signal. 1 Select the channel to be monitored. Only one channel can be m...

To Set a Scan Interval You can set the instrument’s internal timer to automatically scan at aspecific interval (e.g., start a new scan sweep every 10 seconds) or whenan external TTL trigger pulse is received. You can configure the instrument to scan continuously or to stop after sweeping through the...

To Apply Mx+B Scaling to Measurements The scaling function allows you to apply a gain and offset to all readings on a specified multiplexer channel during a scan. In addition to settingthe gain (“M”) and offset (“B”) values, you can also specify a custommeasurement label for your scaled readings ( R...

To Configure Alarm Limits The instrument has four alarms which you can configure to alert youwhen a reading exceeds specified limits on a channel during a scan.You can assign a high limit, a low limit, or both to any configuredchannel in the scan list. You can assign multiple channels to any of thef...

4 Set the limit value. The alarm limit values are stored in non-volatile memory for the specified channels. The default values for the high and low limits are “0”.The low limit must always be less than or equal to the high limit, even ifyou are using only one of the limits. A Factory Reset clears al...

To Read a Digital Input Port The multifunction module (HP 34907A) has two non-isolated 8-bitinput/output ports which you can use for reading digital patterns.You can read the live status of the bits on the port or you can configurea scan to include a digital read. 1 Select the Digital Input port. Se...

To Write to a Digital Output Port The multifunction module (HP 34907A) has two non-isolated 8-bitinput/output ports which you can use for outputting digital patterns. 1 Select the Digital Output port. Select the slot containing the multifunction module and continueturning the knob until DIN is displ...

To Read the Totalizer Count The multifunction module (HP 34907A) has a 26-bit totalizer which cancount pulses at a 100 kHz rate. You can manually read the totalizercount or you can configure a scan to read the count. 1 Select the totalizer channel. Select the slot containing the multifunction module...

To Output a DC Voltage The multifunction module (HP 34907A) has two analog outputs capableof outputting calibrated voltages between ± 12 volts. 1 Select a DAC Output channel. Select the slot containing the multifunction module and continueturning the knob until DAC is displayed (channel 04 or 05). 2...

To Configure the Remote Interface The instrument is shipped with both an HP-IB ( IEEE -488) interface and an RS -232 interface. Only one interface can be enabled at a time. The HP-IB interface is selected when the instrument is shipped from the factory. HP-IB Configuration 1 Select the HP-IB interfa...

RS-232 Configuration 1 Select the RS-232 interface. 5 6 2 Select the baud rate. Select one of the following: 1200, 2400, 4800, 9600, 19200, 38400,57600 ( factory setting ), or 115200 baud. % $ 8 ' 3 Select the parity and number of data bits. Select one of the following: None (8 data bits, factory se...

To Store the Instrument State You can store the instrument state in one of five non-volatile storagelocations. A sixth storage location automatically holds the power-downconfiguration of the instrument. When power is restored, the instrumentcan automatically return to its state before power-down (a ...

System Overview This chapter provides an overview of a computer-based system anddescribes the parts of a data acquisition system. This chapter is dividedinto the following sections: • Data Acquisition System Overview, see below • Signal Routing and Switching, starting on page 57 • Measurement Input,...

The system configuration shown on the previous page offers thefollowing advantages: • You can use the HP 34970A to perform data storage, data reduction,mathematical calculations, and conversion to engineering units.You can use the PC to provide easy configuration and data presentation. • You can rem...

Measurement Software A variety of software is available to configure your data acquisitionhardware and manipulate and display your measurement data. Data Logging and Monitoring HP BenchLink Data Logger is a Windows ® -based application designed to make it easy to use the HP 34970A with your PC for g...

The HP 34970A Data Acquisition / Switch Unit As shown below, the logic circuitry for the HP 34970A is divided intotwo sections: earth-referenced and floating . These two sections are isolated from each other in order to maintain measurement accuracyand repeatability ( for more information on ground ...

Plug-In Modules The HP 34970A offers a complete selection of plug-in modules to giveyou high-quality measurement, switching, and control capabilities.The plug-in modules communicate with the floating logic via the internalisolated digital bus. The multiplexer modules also connect to theinternal DMM ...

System Cabling The plug-in modules have screw-terminal connectors to make it easy toconnect your system cabling. The type of cabling that you use to connectyour signals, transducers, and sensors to the module is critical tomeasurement success. Some types of transducers, such as thermocouples,have ve...

Transducers and Sensors Transducers and sensors convert a physical quantity into an electricalquantity. The electrical quantity is measured and the result is thenconverted to engineering units. For example, when measuring athermocouple, the instrument measures a dc voltage and mathematicallyconverts...

Signal Routing and Switching The switching capabilities of the plug-in modules available with theHP 34970A provide test system flexibility and expandability. You canuse the switching plug-in modules to route signals to and from your testsystem or multiplex signals to the internal DMM or external ins...

Multiplexer Switching Multiplexers allow you to connect one of multiple channels to a common channel, one at a time. A simple 4-to-1multiplexer is shown below. When you combine a multiplexer with ameasurement device, like the internal DMM , you create a scanner. For more information on scanning, see...

Measurement Input The HP 34970A allows you to combine a DMM (either internal or external) with multiplexer channels to create a scan . During a scan, the instrument connects the DMM to the configured multiplexer channels one at a time and makes a measurement on each channel. Any channel that can be ...

Main Processor The main processor, located in the floating logic section, controls the input signal conditioning, ranging, and the ADC . The main processor accepts commands from, and sends measurementresults to, the earth-referenced logic section. The main processorsynchronizes measurements during s...

You can configure the event or action that controls the onset of eachsweep through the scan list (a sweep is one pass through the scan list): • You can set the instrument’s internal timer to automatically scan ata specific interval as shown below. You can also program a time delaybetween channels in...

Scanning With External Instruments If your application doesn’t require the built-in measurement capabilitiesof the HP 34970A, you can order it without the internal DMM . In this configuration, you can use the HP 34970A for signal routing or controlapplications. If you install a multiplexer plug-in m...

The Multifunction Module The multifunction module (HP 34907A) adds two additional measurementinput capabilities to the system: digital input and event totalize . The multifunction module also contains a dual voltage output (DAC)which is described in more detail on page 68. Digital Input The multifun...

Control Output In addition to signal routing and measurement, you can also use theHP 34970A to provide simple control outputs. For example, you cancontrol external high-power relays using the actuator module or adigital output channel. The Multifunction Module The multifunction module (HP 34907A) ad...

Voltage (DAC) Output The multifunction module has two analog outputs capable of outputting calibrated voltages between ± 12 volts with 16 bits of resolution. Each DAC ( Digital-to-Analog Converter ) channel can be used as a programmable voltage source for analog input control ofother devices. A simp...

The Actuator / General-Purpose Switch You can think of the HP 34903A Actuator as a control output because itis often used to control external power devices. The actuator provides20 independent, isolated Form C ( SPDT ) switches. Each channel can switch up to 300V dc or ac rms. Each switch can alsosw...

Features and Functions You will find that this chapter makes it easy to look up all the detailsabout a particular feature of the HP 34970A. Whether you are operating the instrument from the front panel or over the remote interface, thischapter will be useful. This chapter is divided into the followi...

SCPI Language Conventions Throughout this manual, the following conventions are used for SCPI command syntax for remote interface programming: • Square brackets ( [ ] ) indicate optional keywords or parameters. • Braces ( { } ) enclose parameter choices within a command string. • Triangle brackets (...

Scanning The instrument allows you to combine a DMM (either internal or external) with multiplexer channels to create a scan . During a scan, the instrument connects the DMM to the configured multiplexer channels one at a time and makes a measurement on each channel. Any channel that can be “read” b...

Power Failure • When shipped from the factory, the instrument is configured toautomatically recall the power-down state when power is restored.In this configuration, the instrument will automatically recall theinstrument state at power-down and resume a scan in progress.If you do not want the power-...

Adding Channels to a Scan List Before you can initiate a scan, you must configure the channels to bescanned and set up a scan list (these two operations occur simultaneously from the front panel). The instrument automatically scans theconfigured channels in ascending order from slot 100 through slot...

Scan Interval You can configure the event or action that controls the onset of eachsweep through the scan list (a sweep is one pass through the scan list): • You can set the instrument’s internal timer to automatically scan at aspecific interval. You can also program a time delay betweenchannels in ...

Scan Once In this configuration, the instrument waits for either a front-panel key press or a remote interface command before sweepingthrough the scan list. • All readings from the scan are stored in non-volatile memory.Readings accumulate in memory until the scan is terminated (until thescan count ...

External Scanning In this configuration, the instrument sweeps through the scan list once each time a low-going TTL pulse is received on the rear-panel Ext Trig Input line (pin 6). • You can specify a scan count which sets the number of externalpulses the instrument will accept before terminating th...

Scan Count You can specify the number of times the instrument will sweep throughthe scan list. When the specified number of sweeps have occurred, thescan stops. • Select a scan count between 1 to 50,000 scan sweeps, or continuous. • During an Interval Scan ( see page 80 ), the scan count sets the nu...

Reading Format During a scan, the instrument automatically adds a time stamp toall readings and stores them in non-volatile memory. Each reading isstored with measurement units, time stamp, channel number, andalarm status information. From the remote interface, you can specifywhich information you w...

Channel Delay You can control the pace of a scan sweep by inserting a delay betweenmultiplexer channels in the scan list (useful for high-impedance orhigh-capacitance circuits). The delay is inserted between the relayclosure and the actual measurement on the channel. The programmedchannel delay over...

Automatic Channel Delays If you do not specify a channel delay, the instrument selects a delayfor you. The delay is determined by function, range, integration time,and ac filter setting as shown below. DC Voltage, Thermocouple, DC Current (for all ranges): Integration Time Channel Delay PLC > 1 P...

• Front-Panel Operation : CH DELAY AUTO • Remote Interface Operation : The following command enables an automatic channel delay on channel 01. ROUT:CHAN:DELAY:AUTO ON,( @ 101) Selecting a specific channel delay using the ROUTe:CHANnel:DELay command disables the automatic channel delay. Viewing Readi...

• Readings acquired during a Monitor are not stored in memory (however, all readings from a scan in progress at the same time arestored in memory). • The MEASure? and READ? commands send readings directly to the instrument’s output buffer but readings are not stored in memory. You will not be able t...

Single-Channel Monitoring In the Monitor function, the instrument takes readings as often as it canon a single channel, even during a scan. This feature is useful for trouble-shooting your system before a test or for watching an important signal. Any channel that can be “read” by the instrument can ...

• An externally-controlled scan can also include a read of a digital portor a read of the totalizer count on the multifunction module. Whenthe channel advance reaches the first digital channel, the instrumentscans through all of the digital channels in that slot and stores thereadings in reading mem...

General Measurement Configuration This section contains general information to help you configure theinstrument for making measurements during a scan. Since theseparameters are used by several measurement functions, the discussionis combined into one common section. Refer to the later sections in th...

Measurement Resolution Resolution is expressed in terms of number of digits the instrument can measure or display on the front panel. You can set the resolution to 4, 5, or 6 full digits , plus a “ 1 ⁄ 2 ” digit which can only be a “0” or “1”. To increase your measurement accuracy and improve noise ...

Custom A/D Integration Time Integration time is the period of time that the instrument’s analog-to-digital ( A/D ) converter samples the input signal for a measurement. Integration time affects the measurement resolution (for betterresolution, use a longer integration time) and measurement speed(for...

• The instrument selects 1 PLC when the measurement function is changed and after a Factory Reset ( *RST command). An Instrument Preset ( SYSTem:PRESet command) or Card Reset ( SYSTem:CPON command) does not change the integration time setting. • Front-Panel Operation : First, select the measurement ...

Autozero When autozero is enabled (default), the instrument internally disconnects the input signal following each measurement, and takes a zero reading . It then subtracts the zero reading from the preceding reading. This prevents offset voltages present on the instrument’s inputcircuitry from affe...

Temperature Measurement Configuration This section contains information to help you configure the instrumentfor making temperature measurements. For more information on thetypes of temperature transducers, see “Temperature Measurements”starting on page 345 in chapter 8. The instrument supports direc...

Thermocouple Measurements To connect a thermocouple to the module’s screw terminals, see page 21. • The instrument supports the following thermocouple types: B, E, J, K, N, R, S, and T using ITS -90 software conversions. The default is a J-Type thermocouple. • Thermocouple measurements require a ref...

RTD Measurements To connect an RTD to the module’s screw terminals, see page 21. • The instrument supports RTD s with α = 0.00385 (DIN / IEC 751) or α = 0.00391 using ITS -90 software conversions. The default is α = 0.00385. • The resistance of an RTD is nominal at 0 ° C and is referred to as R 0 . ...

Thermistor Measurements To connect a thermistor to the module’s screw terminals, see page 21. • The instrument supports 2.2 k Ω (44004), 5 k Ω (44007), and 10 k Ω (44006) thermistors. • Front-Panel Operation : To select the thermistor function for the active channel, choose the following items. TEMP...

Voltage Measurement Configuration To connect voltage sources to the module’s screw terminals, see page 21. This section contains information to help you configure the instrumentfor making voltage measurements. The instrument can measure dc andtrue RMS ac-coupled voltages on the measurement ranges sh...

• Remote Interface Operation : You can enable or disable the automatic input resistance mode on the specified channels. With AUTO OFF (default), the input resistance is fixed at 10 M Ω for all ranges. With AUTO ON , the input resistance is set to >10 G Ω for the three lowest dc voltage ranges. Th...

Resistance Measurement Configuration To connect resistances to the module’s screw terminals, see page 21. This section contains information to help you configure the instrumentfor making resistance measurements. Use the 2-wire method for ease ofwiring and higher density or the 4-wire method for impr...

Current Measurement Configuration To connect a current source to the module’s screw terminals, see page 21. This section contains information to help you configure the instrumentfor making current measurements on the HP 34901A multiplexermodule. This module has two fused channels for direct dc and a...

Frequency Measurement Configuration To connect an ac source to the module’s screw terminals, see page 21. Low Frequency Timeout The instrument uses three different timeout ranges for frequencymeasurements. The instrument selects a slow , medium , or fast timeout based on the input frequency that you...

Mx+B Scaling The scaling function allows you to apply a gain and offset to all readings on a specified multiplexer channel during a scan. In addition to settingthe gain (“M”) and offset (“B”) values, you can also specify a custommeasurement label for your scaled readings ( RPM , PSI , etc.). You can...

• During a Monitor operation, the gain and offset values are applied toall readings on the specified channel. • You can specify a custom label with up to three characters. You canuse letters (A-Z), numbers (0-9), an underscore ( _ ), or the “#” characterwhich displays a degree symbol ( ° ) on the fr...

• Front-Panel Operation : The menu automatically guides you through the gain, offset, and measurement label settings. SET GAIN , SET OFFSET , SET LABEL To reset the gain, offset, and measurement label to their defaults,go to the corresponding level in the menu and turn the knob. To turnscaling off (...

• You can assign an alarm to any configured channel and multiplechannels can be assigned to the same alarm number. However,you cannot assign alarms on a specific channel to more than onealarm number. • When an alarm occurs, the instrument stores relevant informationabout the alarm in the queue. This...

• Alarms are logged in the alarm queue only when a reading crosses alimit, not while it remains outside the limit and not when it returnsto within limits. • Four TTL alarm outputs are available on the rear-panel Alarms connector. You can use these hardware outputs to trigger externalalarm lights, si...

Viewing Stored Alarm Data If an alarm occurs on a channel as it is being scanned, then that channel’salarm status is stored in reading memory as the readings are taken. As alarm events are generated, they are also logged in an alarm queue , which is separate from reading memory. This is the only pla...

Using the Alarm Output Lines Four TTL alarm outputs are available on the rear-panel Alarms connector. You can use these hardware outputs to trigger externalalarm lights, sirens, or send a TTL pulse to your control system. You can assign an alarm to any configured channel and multiple channels can be...

• You can control the slope of the pulse from the alarm outputs(the selected configuration is used for all four outputs). In the falling edge mode, 0V ( TTL low) indicates an alarm. In the rising edge mode, +5V ( TTL high ) indicates an alarm. A Factory Reset ( *RST command) will reset the slope to ...

Using Alarms With the Multifunction Module You can configure the instrument to generate an alarm when a specificbit pattern or bit pattern change is detected on a digital input channelor when a specific count is reached on a totalizer channel. These channels do not have to be part of the scan list t...

• Remote Interface Operation (Digital Input Channel): To assign the alarm number to report any alarm conditions on the specified digitalinput channels, use the following command. OUTPut:ALARm[1|2|3|4]:SOURce ( @ < ch_list >) To configure alarms on the specified digital input channel, usethe fo...

Example: Configuring an Alarm on a Digital Input Assume that you want to generate an alarm when a binary pattern of“1 0 0 0 ” is read on the upper four bits of port 1. Send the followingcommands to configure the port for an alarm. CALC:COMP:TYPE EQUAL,( @ 301) CALC:COMP:DATA 128,( @ 301) CALC:COMP:M...

Digital Input Operations The multifunction module (HP 34907A) has two non-isolated 8-bitinput/output ports which you can use for reading digital patterns.You can read the live status of the bits on the port or you can configurea scan to include a digital read. • The digital input channels are number...

Totalizer Operations The multifunction module has a 26-bit totalizer which can count TTL pulses at a 100 kHz rate. You can manually read the totalizer countor you can configure a scan to read the count. • The totalizer channel is numbered “ s 03”, where s represents the slot number. • You can config...

Digital Output Operations The multifunction module (HP 34907A) has two non-isolated 8-bitinput/output ports which you can use for outputting digital patterns. • The digital output channels are numbered “ s 01” (lower byte) and “ s 02” (upper byte), where s represents the slot number. • You cannot co...

DAC Output Operations The multifunction module (HP 34907A) has two low-noise analogoutputs capable of outputting calibrated voltages between ± 12 volts with 16 bits of resolution. Each DAC ( Digital-to-Analog Converter ) channel can be used as a programmable voltage source for analog input control o...

System-Related Operations This section gives information on system-related topics such as storinginstrument states, reading errors, running a self-test, displayingmessages on the front panel, setting the system clock, disabling theinternal DMM , reading the firmware revisions, and reading the relay ...

Error Conditions When the front-panel ERROR annunciator turns on, one or more command syntax or hardware errors have been detected. A record ofup to 10 errors is stored in the instrument’s error queue. See chapter 6 for a complete listing of the errors. • Errors are retrieved in first-in-first-out (...

Display Control For security reasons or for a slight increase in scanning rates, you maywant to turn off the front-panel display. From the remote interface,you can also display a 13-character message on the front-display. • You can only disable the front-panel display by sending a commandfrom the re...

Real-Time System Clock During a scan, the instrument stores all readings and alarms withthe current time and date. The instrument stores the time and dateinformation in non-volatile memory. • When shipped from the factory, the instrument is set to the currenttime and date (U.S. Mountain Time). • Fro...

Firmware Revision Query The instrument has three microprocessors for control of various internalsystems. Each plug-in module also has its own on-board microprocessor.You can query the instrument and each module to determine whichrevision of firmware is installed for each microprocessor. • The instru...

Relay Cycle Count The instrument has a Relay Maintenance System to help you predict relay end-of-life. The instrument counts the cycles on each relay in theinstrument and stores the total count in non-volatile memory on eachswitch module. You can use this feature on any of the relay modules andthe i...

• Front-Panel Operation : To read the count on the active channel, choose the following item and then turn the knob. To read the counton the internal DMM relays, turn the knob counterclockwise beyond the lowest numbered channel in the instrument. To read the “hidden”backplane and bank relays, turn t...

SCPI Language Version Query The instrument complies with the rules and conventions of the presentversion of SCPI ( Standard Commands for Programmable Instruments ). You can determine the SCPI version with which the instrument is in compliance by sending a command from the remote interface. You canno...

Remote Interface Configuration This section gives information on configuring the instrument for remoteinterface communication. For more information on configuring theinstrument from the front panel, see “To Configure the Remote Interface”starting on page 46. For more information on the SCPI commands...

Remote Interface Selection The instrument is shipped with both an HP-IB ( IEEE -488) interface and an RS -232 interface. Only one interface can be enabled at a time. The HP-IB interface is selected when the instrument is shipped from the factory. • The interface selection is stored in non-volatile m...

Baud Rate Selection (RS-232) You can select one of eight baud rates for RS -232 operation. The rate is set to 57,600 baud when the instrument is shipped from the factory. You can set the baud rate from the front panel only. • Select one of the following: 1200, 2400, 4800, 9600, 19200, 38400, 57600 (...

Flow Control Selection (RS-232) You can select one of several flow control methods to coordinate the transfer of data between the instrument and your computer or modem.The method that you select will be determined by the flow method usedby your computer or modem. You can select the flow control meth...

Calibration Overview This section gives a brief introduction to the calibration features of theinstrument and plug-in modules. For a more detailed discussion of thecalibration procedures, see chapter 4 in the HP 34970A Service Guide . Calibration Security This feature allows you to enter a security ...

To Secure Against Calibration You can secure the instrument either from the front panel or over the remote interface. The instrument issecured when shipped from the factory and the security code is set to“ HP034970 ”. • Once you enter a security code, that code must be used for bothfront-panel and r...

Calibration Message The instrument allows you to store one message in calibration memoryin the mainframe. For example, you can store such information as thedate when the last calibration was performed, the date when the nextcalibration is due, the instrument’s serial number, or even the name andphon...

Calibration Count You can query the instrument to determine how many calibrations havebeen performed. Note that your instrument was calibrated before it leftthe factory. When you receive your instrument, be sure to read thecount to determine its initial value. • The calibration count is stored in no...

Factory Reset State The table below shows the state of the instrument after a FACTORY RESET from the Sto/Rcl menu or *RST command from the remote interface. Measurement Configuration Function Range Resolution Integration Time Input Resistance Channel Delay Totalizer Reset Mode Totalizer Edge Detect ...

Instrument Preset State The table below shows the state of the instrument after a PRESET from the Sto/Rcl menu or SYSTem:PRESet command from the remote interface. Measurement Configuration Function Range Resolution Advanced Settings Totalizer Reset Mode Totalizer Edge Detect Scanning Operations Scan...

Multiplexer Module Default Settings The table below shows the default settings for each measurementfunction on the multiplexer modules. When you configure a channel fora particular function, these are the default settings. Temperature Measurements Temperature Units Integration Time Display Resolutio...

Module Overview This section gives a description of each plug-in module, includingsimplified schematics and block diagrams. A wiring log is also includedto make it easy to document your wiring configuration for each module. For complete specifications on each plug-in module, refer to the modulesecti...

HP 34902A 16-Channel Multiplexer This module is divided into two banks of eight channels each. All 16channels switch both HI and LO inputs, thus providing fully isolated inputs to the internal DMM or an external instrument. When making4-wire resistance measurements, the instrument automatically pair...

HP 34903A 20-Channel Actuator This module contains 20 independent, SPDT (Form C) latching relays. Screw terminals on the module provide access to the Normally-Open,Normally-Closed, and Common contacts for each switch. This module does not connect to the internal DMM. A breadboard area is provided ne...

HP 34904A 4x8 Matrix Switch This module contains 32 two-wire crosspoints organized in a 4-row by8-column configuration. You can connect any combination of inputs andoutputs at the same time. This module does not connect to the internal DMM . Each crosspoint relay has its own unique channel label rep...

HP 34905A/6A Dual 4-Channel RF Multiplexers These modules consist of two independent 4-to-1 multiplexers.The channels in each bank are organized in a “tree” structure to providehigh isolation and low VSWR . Both banks have a common earth ground. This module does not connect to the internal DMM . You...

HP 34907A Multifunction Module This module combines two 8-bit ports of digital input/output, a 100 kHztotalizer, and two ± 12 analog outputs. For greater flexibility, you can read digital inputs and the totalizer count during a scan. Digital Input/Output T h e DIO c o n s is t s o f tw o 8 - bi t p ...

HP 34908A 40-Channel Single-Ended Multiplexer The module is divided into two banks of 20 channels each. All of the40 channels switch HI only, with a common LO for the module. The module has a built-in isothermal block to minimize errors due tothermal gradients when measuring thermocouples. NOTES: • ...

Remote Interface Reference • SCPI Command Summary, starting on page 181 • Simplified Programming Overview, starting on page 201 • The MEASure? and CONFigure Commands, starting on page 207 • Setting the Function, Range, and Resolution, starting on page 214 • Temperature Configuration Commands, starti...

SCPI Command Summary Throughout this manual, the following conventions are used for SCPI command syntax for remote interface programming: • Square brackets ( [ ] ) indicate optional keywords or parameters. • Braces ( { } ) enclose parameter choices within a command string. • Triangle brackets ( <...

Scan Measurement Commands ( see page 226 for more information ) MEASure :TEMPerature? { TCouple|RTD|FRTD|THERmistor|DEF} ,{< type >|DEF}[,1[,{< resolution >|MIN|MAX|DEF}]] ,( @ < scan_list >) :VOLTage:DC? [{< range >| AUTO|MIN|MAX|DEF} [,< resolution >|MIN|MAX|DEF}],] (...

Scan Configuration Commands ( see page 226 for more information ) ROUTe :SCAN ( @ < scan_list >) :SCAN? :SCAN:SIZE? TRIGger :SOURce {BUS| IMMediate|EXTernal|ALARm1|ALARm2|ALARm3|ALARm4|TIMer} :SOURce? TRIGger :TIMer {< seconds >| MIN|MAX} :TIMer? TRIGger :COUNt {< count >| MIN|MAX|...

Scan Statistics Commands ( see page 233 for more information ) CALCulate :AVERage:MINimum? [( @ < ch_list >)] :AVERage:MINimum:TIME? [( @ < ch_list >)] :AVERage:MAXimum? [( @ < ch_list >)] :AVERage:MAXimum:TIME? [( @ < ch_list >)] :AVERage:AVERage? [( @ < ch_list >)] :A...

Scanning With an External Instrument ( see page 239 for more information ) ROUTe :SCAN ( @ < scan_list >) :SCAN? :SCAN:SIZE? TRIGger :SOURce {BUS|IMMediate|EXTernal| TIMer} :SOURce? TRIGger :TIMer {< seconds >| MIN|MAX} :TIMer? TRIGger :COUNt {< count >|MIN|MAX| INFinity} :COUNt? R...

Temperature Configuration Commands ( see page 219 for more information ) CONFigure :TEMPerature { TCouple|RTD|FRTD|THERmistor|DEF} ,{< type >|DEF}[,1[,{< resolution >|MIN|MAX|DEF}]] ,( @ < scan_list >) CONFigure? [( @ < ch_list >)] UNIT :TEMPerature { C|F|K}[,( @ < ch_list...

Voltage Configuration Commands ( see page 223 for more information ) CONFigure :VOLTage:DC [{< range >| AUTO|MIN|MAX|DEF} [,< resolution >|MIN|MAX|DEF}],] ( @ < scan_list >) CONFigure? [( @ < ch_list >)] [SENSe:] VOLTage:DC:RANGe {< range >|MIN|MAX}[,( @ < ch_list &g...

Resistance Configuration Commands ( see page 224 for more information ) CONFigure :RESistance [{< range >| AUTO|MIN|MAX|DEF} [,< resolution >|MIN|MAX|DEF}],] ( @ < scan_list >) CONFigure? [( @ < ch_list >)] [SENSe:] RESistance:RANGe {< range >|MIN|MAX}[,( @ < ch_list...

Current Configuration Commands ( see page 224 for more information ) Valid only on channels 21 and 22 on the HP 34901A multiplexer module. CONFigure :CURRent:DC [{< range >| AUTO|MIN|MAX|DEF} [,< resolution >|MIN|MAX|DEF}],] ( @ < scan_list >) CONFigure? [( @ < ch_list >)] [S...

Frequency and Period Configuration Commands ( see page 214 for more information ) CONFigure :FREQuency [{< range >| AUTO|MIN|MAX|DEF} [,< resolution >|MIN|MAX|DEF}],] ( @ < scan_list >) CONFigure? [( @ < ch_list >)] [SENSe:] FREQuency:VOLTage:RANGe {< range >|MIN|MAX}[,...

Mx+B Scaling Commands ( see page 244 for more information ) CALCulate :SCALe:GAIN < gain >[,( @ < ch_list >)] :SCALe:GAIN? [( @ < ch_list >)] :SCALe:OFFSet < offset >[,( @ < ch_list >)] :SCALe:OFFSet? [( @ < ch_list >)] :SCALe:UNIT < quoted_string >[,( @ <...

Alarm Limit Commands ( see page 247 for more information ) OUTPut :ALARm[ 1|2|3|4]:SOURce ( @ < ch_list >) :ALARm[ 1|2|3|4]:SOURce? CALCulate :LIMit:UPPer < hi_limit >[,( @ < ch_ list >)] :LIMit:UPPer? [( @ < ch_list >)] :LIMit:UPPer:STATe {OFF|ON}[,( @ < ch_list >)] :L...

Digital Input Commands ( see page 255 for more information ) Ch 01 DIO (LSB) Ch 02 DIO (MSB) Ch 03 Totalizer Ch 04 DAC Ch 05 DAC CONFigure:DIGital:BYTE ( @ < scan_list >) CONFigure? [( @ < ch_list >)] [SENSe:]DIGital:DATA:{ BYTE|WORD}? [( @ < ch_list >)] Totalizer Commands ( see pa...

Digital Output Commands ( see page 258 for more information ) Ch 01 DIO (LSB) Ch 02 DIO (MSB) Ch 03 Totalizer Ch 04 DAC Ch 05 DAC SOURce :DIGital:DATA[:{ BYTE|WORD}] < data > ,( @ < ch_list >) :DIGital:DATA[:{ BYTE|WORD}]? ( @ < ch _list >) SOURce:DIGital:STATe? ( @ < ch_list &g...

Scan Triggering Commands ( see page 228 for more information ) TRIGger :SOURce {BUS| IMMediate|EXTernal|ALARm1|ALARm2|ALARm3|ALARm4|TIMer} :SOURce? TRIGger :TIMer {< seconds >| MIN|MAX} :TIMer? TRIGger :COUNt {< count >| MIN|MAX|INFinity} :COUNt? *TRG INITiate READ? State Storage Command...

System-Related Commands ( see page 264 for more information ) SYSTem :DATE < yyyy >,< mm >,< dd > :DATE? :TIME < hh >,< mm >,< ss.sss > :TIME? FORMat :READing:TIME:TYPE {ABSolute| RELative} :READing:TIME:TYPE? *IDN? SYSTem:CTYPe? {100|200|300} DIAGnostic :POKE:SLO...

Interface Configuration Commands ( see page 269 for more information ) SYSTem:INTerface {GPIB|RS232} SYSTem:LOCal SYSTem:REMote SYSTem:RWLock Status System Commands ( see page 286 for more information ) *STB?*SRE < enable_value > *SRE? STATus :QUEStionable:CONDition? :QUEStionable[:EVENt]? :QU...

Calibration Commands ( see page 292 for more information ) CALibration? CALibration:COUNt? CALibration :SECure:CODE < new_code > :SECure:STATe {OFF| ON},< code > :SECure:STATe? CALibration :STRing < quoted_string > :STRing? CALibration :VALue < value > :VALue? Service-Related...

IEEE 488.2 Common Commands *CLS *ESR?*ESE < enable_value > *ESE? *IDN? *OPC *OPC? *PSC {0|1}*PSC? *RST *SAV {0|1|2|3|4|5}*RCL {0|1|2|3|4|5} *STB?*SRE < enable_value > *SRE? *TRG *TST? Chapter 5 Remote Interface ReferenceSCPI Command Summary 200

Simplified Programming Overview This section gives an overview of the basic techniques used to programthe HP 34970A over the remote interface. This section is only anoverview and does not give all of the details you will need to write yourown application programs. Refer to the remainder of this chap...

Using the MEASure? Command The MEASure? command provides the easiest way to program the instrument for scanning. However, this command does not offer muchflexibility. When you execute this command, the instrument usesdefault values for the requested measurement configuration andimmediately performs ...

Using the range and resolution Parameters With the MEASure? and CONFigure commands, you can select the measurement function, range, and resolution all in one command.Use the range parameter to specify a fixed range larger than the expected value of the input signal. You can also set the range parame...

Using the READ? Command The READ? command changes the state of the scan trigger system from the “idle” state to the “wait-for-trigger” state. Scanning will begin whenthe specified trigger conditions are satisfied following the receipt of the READ? command. Readings are then sent immediately to the i...

The MEASure? and CONFigure Commands Both the MEASure? and CONFigure commands reset all measurement parameters to their default values. For more information on the defaultsettings for these commands, see the table on page 201. • For the range parameter, MIN selects the lowest range for the selected f...

MEASure:TEMPerature? {RTD|FRTD},{85|91|DEF} [,1[,< resolution >|MIN|MAX|DEF}]] ,( @ < scan_list >) Configure the specified channels for 2-wire or 4-wire RTD measurements and immediately sweep through the scan list one time. Use “85” tospecify α = 0.00385 or “91” to specify α = 0.00391. N...

MEASure:RESistance?MEASure:FRESistance? [{< range >|AUTO|MIN|MAX|DEF} [,< resolution >|MIN|MAX|DEF}],] ( @ < scan_list >) Configure the specified channels for 2-wire or 4-wire measurements andimmediately sweep through the scan list one time. Note that this command also redefines th...

MEASure:DIGital:BYTE? ( @ < scan_list >) Configure the instrument to read the specified digital input channels onthe multifunction module and immediately sweep through the scan listone time. Note that this command also redefines the scan list . The readings are sent directly to the instrument’...

CONFigure Command Syntax CONFigure:TEMPerature {TCouple},{B|E|J|K|N|R|S|T|DEF} [,1[,< resolution >|MIN|MAX|DEF}]] ,( @ < scan_list> ) Configure the specified channels for thermocouple measurements but do not initiate the scan. Note that this command also redefines the scan list . The def...

CONFigure:FREQuency CONFigure:PERiod [{< range >|AUTO|MIN|MAX|DEF} [,< resolution >|MIN|MAX|DEF}],] ( @ < scan_list >) Configure the specified channels for frequency or period measurementsbut do not initiate the scan. Note that this command also redefines the scan list . CONFigure:...

Setting the Function, Range, and Resolution See also “General Measurement Configuration” in chapter 4 startingon page 98. • For 4-wire measurements, the instrument automatically pairschannel n with channel n+10 (34901A) or n+8 (34902A) to provide the source and sense connections. Specify the paired ...

[SENSe:] VOLTage:DC:RANGe {< range >|MIN|MAX}[,( @ < ch_list >)] VOLTage:AC:RANGe {< range >|MIN|MAX}[,( @ < ch_list >)] RESistance:RANGe {< range >|MIN|MAX}[,( @ < ch_list >)] FRESistance:RANGe {< range >|MIN|MAX}[,( @ < ch_list >)] CURRent:DC:RANGe {...

[SENSe:] VOLTage:DC:RANGe:AUTO? [( @ < ch_list >)] VOLTage:AC:RANGe:AUTO? [( @ < ch_list >)] RESistance:RANGe:AUTO? [( @ < ch_list >)] FRESistance:RANGe:AUTO? [( @ < ch_list >)] CURRent:DC:RANGe:AUTO? [( @ < ch_list >)] CURRent:AC:RANGe:AUTO? [( @ < ch_list >)] FR...

[SENSe:] VOLTage:DC:APERture {< time >|MIN|MAX}[,( @ < ch_list >)] RESistance:APERture {< time >|MIN|MAX}[,( @ < ch_list >)] FRESistance:APERture {< time >|MIN|MAX}[,( @ < ch_list >)] CURRent:DC:APERture {< time >|MIN|MAX}[,( @ < ch_list >)] Select the...

[SENSe:] TEMPerature :NPLC {0.02|0.2|1|2|10|20|100|200|MIN|MAX}[,( @ < ch_list >)] VOLTage:DC :NPLC {0.02|0.2|1|2|10|20|100|200|MIN|MAX}[,( @ < ch_list >)] RESistance :NPLC {0.02|0.2|1|2|10|20|100|200|MIN|MAX}[,( @ < ch_list >)] FRESistance :NPLC {0.02|0.2|1|2|10|20|100|200|MIN|MAX...

Temperature Configuration Commands See also “Temperature Measurement Configuration” in chapter 4 startingon page 106. General Temperature Commands UNIT :TEMPerature {C|F|K}[,( @ < ch_list >)] :TEMPerature? [( @ < ch_list >)] Select the temperature measurement units on the specified chann...

Thermocouple Commands [SENSe:]TEMPerature:TRANsducer :TCouple:TYPE {B|E|J|K|N|R|S|T}[,( @ < ch_list >)] :TCouple:TYPE? [( @ < ch_list >)] Select the thermocouple type to use on the specified channels.The default is a J-Type thermocouple. The :TYPE? query returns the thermocouple type cur...

RTD Commands [SENSe:]TEMPerature:TRANsducer :RTD:TYPE {85|91}[,( @ < ch_list >)] :RTD:TYPE? [( @ < ch_list >)] :FRTD:TYPE {85|91}[,( @ < ch_list >)] :FRTD:TYPE? [( @ < ch_list >)] Select the RTD type for 2-wire or 4-wire measurements on the specified channels. Use “85” to spe...

Resistance Configuration Commands See also “Resistance Measurement Configuration” in chapter 4 startingon page 115. [SENSe:] RESistance:OCOMpensated {OFF|ON}[,( @ < ch_list >)] RESistance:OCOMpensated? [( @ < ch_ list >)] FRESistance:OCOMpensated {OFF|ON}[,( @ < ch_list >)] FRESist...

Frequency Configuration Commands See also “Frequency Measurement Configuration” in chapter 4 starting onpage 118. [SENSe:] FREQuency:RANGe:LOWer {3|20|200|MIN|MAX}[,( @ < ch_list >)] FREQuency:RANGe:LOWer? [{( @ < ch_list >)|MIN|MAX}] Specify the lowest frequency expected in the input si...

Scanning Overview See also “Scanning” in chapter 4 starting on page 74. The instrument allows you to combine a DMM (either internal or external) with multiplexer channels to create a scan . During a scan, the instrument connects the DMM to the configured multiplexer channels one at a time and makes ...

Scanning Commands ROUTe :SCAN ( @ < scan_list >) :SCAN? Select the channels to be included in the scan list. To start the scan,use the INITiate or READ? command. To remove all channels from the scan list, send ROUT:SCAN ( @ ) . The :SCAN? query returns a list of channel numbers in the SCPI def...

TRIGger :TIMer {< seconds >|MIN|MAX} :TIMer? Set the scan-to-scan interval (in seconds) for measurements on thechannels in the scan list. This command defines the time from the startof one scan sweep to the start of the next sweep. You can set the intervalto any value between 0 seconds and 359...

ROUTe :CHANnel:DELay:AUTO {OFF|ON}[,( @ < ch_list >)] :CHANnel:DELay:AUTO? [( @ < ch_list >)] Disable or enable an automatic channel delay on the specified channels.If enabled, the delay is determined by the function, range, integrationtime, and ac filter setting ( see “Automatic Channel...

Reading Format Commands During a scan, the instrument automatically adds a time stamp toall readings and stores them in non-volatile memory. Each reading isstored with measurement units, time stamp, channel number, andalarm status information. You can specify which information you wantreturned with ...

Scan Statistics Commands While a scan is running, the instrument automatically stores theminimum and maximum readings and calculates the average for eachchannel. You can read these values at any time, even during a scan.The instrument clears the values when a new scan is started, when the CALC:AVER:...

CALCulate:AVERage:AVERage? [( @ < ch_list >)] Calculate the mathematical average of all readings taken on each of thespecified channels since the start of the scan. Each channel must be amultiplexer channel that has been configured to be part of the scan list.If no data is available for the sp...

SYSTem:TIME:SCAN? Read the time at the start of the scan. This command is not affected bythe FORMat:READ:TIME:TYPE command. Returns the time in the form “ 1997,06,02,18,30,00.000 ” (June 1, 1997 at 6:30 PM ). FETCh? Transfer readings stored in non-volatile memory to the instrument’soutput buffer whe...

Single-Channel Monitoring Overview In the Monitor function, the instrument takes readings as often as it canon a single channel, even during a scan. This feature is useful for trouble-shooting your system before a test or for watching an important signal. Any channel that can be “read” by the instru...

ROUTe :MONitor ( @ < channel >) :MONitor? Select the channel to be monitored. To turn on the monitor function,use the ROUT:MON:STATE ON command (see below). The :SCAN? query returns a list of channel numbers in the SCPI definite length block format. The response begins with the “#” character, ...

Mx+B Scaling Overview See also “Mx+B Scaling” in chapter 4 starting on page 119. The scaling function allows you to apply a gain and offset to all readings on a specified multiplexer channel during a scan. In addition to settingthe gain (“M”) and offset (“B”) values, you can also specify a custommea...

Alarm System Overview See also “Alarm Limits” in chapter 4 starting on page 122. The instrument has four alarms which you can configure to alert youwhen a reading exceeds specified limits on a channel during a scan.You can assign a high limit, a low limit, or both to any configuredchannel in the sca...

Alarm Limit Commands OUTPut :ALARm[1|2|3|4]:SOURce ( @ < ch_list >) :ALARm[1|2|3|4]:SOURce? Assign the alarm number to report any alarm conditions on thespecified channels. If not assigned, all alarms on all channels arereported on Alarm 1 by default. The :SOUR? query returns a list of channel...

CALCulate :LIMit:LOWer < value >[,( @ < ch_ list >)] :LIMit:LOWer? [( @ < ch_list >)] Set the lower limit for alarms on the specified channels. You can set thevalue to any number between -120% and +120% of the highest range,for the present function. The default lower limit is - 1.0...

Alarm Output Commands Four TTL alarm outputs are available on the rear-panel Alarms connector. You can use these hardware outputs to trigger externalalarm lights, sirens, or send a TTL pulse to your control system. Each alarm output line represents the logical “ OR ” of all channels assigned to that...

Digital I/O Alarm Commands See also “Using Alarms With the Multifunction Module” in chapter 4starting on page 130. CALCulate :COMPare:TYPE {EQUal|NEQual}[,( @ < ch_list >)] :COMPare:TYPE? [( @ < ch_list >)] Select the comparison mode for alarms on the specified DIO channels.Select EQUal ...

CALCulate :COMPare:MASK < mask >[,( @ < ch_list >)] :COMPare:MASK? [( @ < ch_list >)] Specify the mask pattern for comparisons on the specified DIO channels. You must specify the mask parameter as a decimal value between 0 and 255 (binary data is not accepted). Specify 1’s for acti...

Digital Input Commands See also “Digital Input Operations” in chapter 4 starting on page 133. MEASure:DIGital:BYTE? ( @ < scan_list >) Configure the instrument to read the specified digital input channels onthe multifunction module and immediately sweep through the scan listone time. Note that...

[SENSe:] TOTalize:SLOPe {NEGative|POSitive}[,( @ < ch_list >)] TOTalize:SLOPe? [( @ < ch_list >)] Configure the totalizer to count on the rising edge (default; positive) orfalling edge (negative) of the input signal. The totalizer channel isnumbered “ s 03”, where s represents the slot n...

ROUTe :CHANnel:FWIRe {OFF|ON} [,( @ < ch_list >)] :CHANnel:FWIRe? [( @ < ch_list >)] This command is valid only when the internal DMM is disabled orremoved from the HP 34970A. Configure the list of channels for 4-wire external scanning without theinternal DMM . When enabled, the instrume...

State Storage Commands The instrument has six storage locations in non-volatile memory tostore instrument states. The locations are numbered 0 through 5.The instrument uses location “0” to automatically hold the state of theinstrument at power down. You can also assign a name to each of thelocations...

MEMory:STATe :NAME {1|2|3|4|5} [,< name >] :NAME? {1|2|3|4|5} Assign a name to the specified storage location (you cannot assign aname to location “0”). You can name a location from the front panel orover the remote interface but you can only recall a named state from thefront panel. From the ...

MEMory:STATe :RECall:AUTO {OFF|ON} :RECall:AUTO? Disable or enable (default) the automatic recall of the power-down statefrom storage location “0” when power is turned on. Select “ ON ” to automatically recall the power-down state when power is turned on.Select “ OFF ” to issue a Factory Reset (and ...

System-Related Commands See also “System-Related Operations” in chapter 4 starting on page 140. SYSTem:DATE < yyyy > , < mm > , < dd > Set the instrument calendar. The setting is stored in non-volatile memory.When shipped from the factory, instrument is set to the current timeand d...

*IDN? Read the instrument’s identification string. The instrument returnsthree numbers for the system firmware. The first number is thefirmware revision number for the measurement processor; the second isfor the input/output processor; and the third is for the front-panelprocessor. An example string...

RS-232 Interface Configuration See also “Remote Interface Configuration” in chapter 4 on page 150. This section contains information to help you use the instrument overthe RS-232 interface. The programming commands for RS-232 are listedon page 269. RS-232 Configuration Overview Configure the RS-232 ...

RS-232 Flow Control Modes You can select one of several flow control methods to coordinate the transfer of data between the instrument and your computer or modem. • None : In this mode, data is sent and received over the interface without any flow control used. When using this method, use a slowerba...

If your computer has a 9-pin serial port with a male connector, use thecable included with the instrument (if you ordered the internal DMM ). If you need an additional cable, order the F1047-80002 cable which is part of the HP 34398A Cable Kit . This cable has a 9-pin female connector on each end. T...

Modem Communications This section gives details on communicating with the instrument froma remote PC using a modem. To communicate over the phone lines, you must have a PC and two modems. One modem is connected to your PC ( local modem ) and the other is connected to the HP 34970A ( remote modem ). ...

The SCPI Status System This section describes the structure of the SCPI status system used by the HP 34970A. The status system records various conditions and states of the instrument in five register groups as shown on the following page.Each of the register groups is made up of several low-level re...

The Status Byte Register The Status Byte register group reports conditions from the otherregister groups. Data in the instrument’s output buffer is immediatelyreported on the “Message Available” bit (bit 4). Clearing an eventregister from one of the other register groups will clear the corresponding...

Using Service Request (SRQ) and Serial Poll You must configure your computer to respond to the IEEE -488 service request ( SRQ ) interrupt to use this capability. Use the Status Byte enable register ( *SRE command) to select which condition bits will assert the IEEE -488 SRQ line. If bit 6 ( RQS ) t...

Using the Message Available Bit (MAV) You can use the Status Byte “Message Available” bit (bit 4) to determinewhen data is available to read into your computer. The instrumentsubsequently clears bit 4 only after all messages have been read fromthe output buffer. To Interrupt Your Bus Controller Usin...

The Questionable Data Register The Questionable Data register group provides information about thequality of the instrument’s measurement results. Any or all of theseconditions can be reported to the Questionable Data summary bit throughthe enable register . To set the enable register mask, you must...

The Standard Event Register The Standard Event register group reports the following types ofinstrument events: power-on detected, command syntax errors,command execution errors, self-test or calibration errors, query errors,or the *OPC command is executed. Any or all of these conditions can be repor...

The Alarm Register The Alarm register group is used to report the status of the fourinstrument alarm limits. Any or all of these alarm conditions can bereported to the Alarm Register summary bit through the enable register . To set the enable register mask, you must write a decimal value to theregis...

The Standard Operation Register The Standard Operation register group is used to report when theinstrument is scanning. Any or all of these conditions can be reported tothe Standard Operation summary bit through the enable register . To set the enable register mask, you must write a decimal value to...

Status System Commands An application program is included in chapter 7 which shows the use ofthe Status System Registers. Refer to page 330 for more information. Status Byte Register Commands See the table on page 277 for the register bit definitions. *STB? Query the summary (condition) register in ...

Questionable Data Register Commands See the table on page 280 for the register bit definitions. STATus:QUEStionable:CONDition? Query the condition register in this register group. This is a read-onlyregister and bits are not cleared when you read the register. A *RST (Factory Reset) will clear all b...

Standard Event Register Commands See the table on page 282 for the register bit definitions. *ESR? Query the event register in this register group. This is a read-onlyregister. Once a bit is set, it remains set until cleared by a *CLS (clear status) command. A query of this register returns a decima...

Alarm Register Commands See the table on page 284 for the register bit definitions. STATus:ALARm:CONDition? Query the condition register in this register group (note that thiscondition register uses only bit 4). This is a read-only register and bitsare not cleared when you read the register. A *RST ...

Standard Operation Register Commands See the table on page 285 for the register bit definitions. STATus:OPERation:CONDition? Query the condition register in this register group. This is a read-onlyregister and bits are not cleared when you read the register. Note thata *RST (Factory Reset) command m...

DATA:POINts:EVENt:THReshold < num_rdgs > DATA:POINts:EVENt:THReshold? Set a bit in the event register when the specified number of readingshave been stored in reading memory during a scan. You can set thememory threshold to any value between 1 reading and 50,000 readings.The default is 1 readi...

Calibration Commands For an overview of the calibration features of the instrument, refer to“Calibration Overview” in chapter 4 starting on page 155. For a moredetailed discussion of the instrument’s calibration procedures,see chapter 4 in the HP 34970A Service Guide . CALibration? Perform a calibra...

Service-Related Commands INSTrument :DMM {OFF|ON} :DMM? Disable or enable the internal DMM . When you change the state of the internal DMM , the instrument issues a Factory Reset ( *RST command). The :DMM? query returns the state of the internal DMM. Returns “0” (disabled) or “1” (enabled). INSTrume...

*RST Reset the instrument to the Factory configuration. See “Factory ResetState” on page 160 in chapter 4 for a complete listing of the instrument’sFactory Reset state. This command is equivalent to selecting FACTORY RESET from the front-panel Sto/Rcl Menu. SYSTem:PRESet Preset the instrument to a k...

An Introduction to the SCPI Language SCPI ( Standard Commands for Programmable Instruments ) is an ASCII -based instrument command language designed for test and measurement instruments. Refer to “Simplified Programming Overview,” starting on page 201, for an introduction to the basic techniques use...

Command Format Used in This Manual The format used to show commands in this manual is shown below: VOLTage:DC:RANGe {< range >|MINimum|MAXimum}[,( @ < ch_list >)] The command syntax shows most commands (and some parameters)as a mixture of upper- and lower-case letters. The upper-case let...

Command Separators A colon ( : ) is used to separate a command keyword from a lower-level keyword. You must insert a blank space to separate a parameter from a command keyword. If a command requires more than one parameter,you must separate adjacent parameters using a comma as shown below: "CONF...

SCPI Parameter Types The SCPI language defines several different data formats to be used in program messages and response messages. Numeric Parameters Commands that require numeric parameters will accept all commonly used decimal representations of numbersincluding optional signs, decimal points, an...

String Parameters String parameters can contain virtually any set of ASCII characters. A string must begin and end with matching quotes; either with a single quote or with a double quote. You can include thequote delimiter as part of the string by typing it twice without anycharacters in between. Th...

Using Device Clear Device Clear is an IEEE-488 low-level bus message which you can useto return the instrument to a responsive state. Different programminglanguages and IEEE-488 interface cards provide access to this capabilitythrough their own unique commands. The status registers, the errorqueue, ...

Error Messages • Errors are retrieved in first-in-first-out ( FIFO ) order. The first error returned is the first error that was stored. Errors are cleared as youread them. When you have read all errors from the queue, the ERROR annunciator turns off and the errors are cleared. The instrumentbeeps o...

Execution Errors -101 Invalid character An invalid character was found in the command string. You may haveused an invalid character such as # , { , $ , or % in the command header or within a parameter. Example : CONF:VOLT:DC { @ 101) -102 Syntax error Invalid syntax was found in the command string. ...

Instrument Errors 111 Channel list: slot number out of range The specified slot number is invalid. The channel number has theform ( @ scc ) , where s is the slot number (100, 200, or 300) and cc is the channel number. Example : CONF:VOLT:DC ( @ 404) 112 Channel list: channel number out of range The ...

261 Not able to execute while scan initiated While a scan is running, you cannot change any parameters that affectthe scan (channel configuration, scan interval, scaling values, alarmlimits, issue a Card Reset, or recall a stored state). To stop a scan inprogress, send the ABORt command or a bus Dev...

303 Module not able to perform requested operation A command was received which is not valid for the specified module.This error is most commonly generated when you send a commandintended for the multifunction module to a switching module. 305 Not able to perform requested operation The requested op...

501 I/O processor: isolator framing error 502 I/O processor: isolator overrun error 511 Communications: RS-232 framing error 512 Communications: RS-232 overrun error 513 Communications: RS-232 parity error 514 RS-232 only: unable to execute using HP-IB There are three commands which are allowed only...

Self-Test Errors The following errors indicate failures that may occur during a self-test.Refer to the HP 34970A Service Guide for more information. 601 Self-test: front panel not responding 602 Self-test: RAM read/write 603 Self-test: A/D sync stuck 604 Self-test: A/D slope convergence 605 Self-tes...

Calibration Errors The following errors indicate failures that may occur during a calibration.Refer to the HP 34970A Service Guide for more information. 701 Cal: security disabled by jumper The calibration security feature has been disabled with a jumper insidethe instrument. When applicable, this e...

Plug-In Module Errors 901 Module hardware: unexpected data received 902 Module hardware: missing stop bit 903 Module hardware: data overrun 904 Module hardware: protocol violation 905 Module hardware: early end of data 906 Module hardware: missing end of data 907 Module hardware: module srq signal s...

Application Programs This chapter contains several example programs to help you developprograms for your specific measurement application. Chapter 5,“Remote Interface Reference,” starting on page 179, lists the syntax forthe SCPI ( Standard Commands for Programmable Instruments ) commands available ...

Example Programs for Excel 7.0 This section contains two example programs written using Excel macros( Visual Basic ® for Applications ) to control the HP 34970A. Using Excel, you can send SCPI commands to configure the instrument and then record measurement data on the Excel spreadsheet. To write an...

Excel 7.0 Example: Port Configuration Macro Option Explicit’ Declarations for VISA.DLL’ Basic I/O OperationsPrivate Declare Function viOpenDefaultRM Lib "VISA32.DLL" Alias "#141" (sesn As Long) As LongPrivate Declare Function viOpen Lib "VISA32.DLL" Alias "#131" (ByVa...

Example Programs for C and C++ The following C programming examples show you how to send andreceive formatted I/O. For more information on non-formatted I/O, referto the HP VISA User’s Guide . The examples in this section show you how to use the SCPI commands for the instrument with the VISA functio...

System Cabling and Connections This section describes methods to reduce measurement errors that canbe introduced by your system cabling. Many system cabling errors canbe reduced or eliminated by selecting the proper cable and groundingscheme for your system. Cable Specifications A wide variety of ge...

• Cable Resistance – Varies with wire gauge size and cable length. Use the largest gauge wire possible and try to keep the cable lengthsas short as possible to minimize the cable resistance. The followingtable lists typical cable resistance for copper wire of several gauge sizes (the temperature coe...

Grounding Techniques One purpose of grounding is to avoid ground loops and minimize noise.Most systems should have at least three separate ground returns. 1. One ground for signals. You may also want to provide separate signal grounds between high-level signals, low-level signals, and digital signal...

Shielding Techniques Shielding against noise must address both capacitive (electrical) andinductive (magnetic) coupling. The addition of a grounded shieldaround the conductor is highly effective against capacitive coupling.In switching networks, this shielding often takes the form of coaxialcables a...

Sources of System Cabling Errors Radio Frequency Interference Most voltage-measuring instruments can generate false readings in the presence of large, high-frequencysignals. Possible sources of high-frequency signals include nearby radioand television transmitters, computer monitors, and cellular te...

Noise Caused by Ground Loops When measuring voltages in circuits where the internal DMM and the device-under-test are both referenced to a common earth ground, a ground loop is formed. As shown below, any voltage difference between the two ground reference points (V ground ) causes a current to flow...

Low-Level AC Measurement Errors When measuring ac voltages less than 100 mV, be aware that these measurements are especiallysusceptible to errors introduced by extraneous noise sources. An exposedtest lead will act as an antenna and the internal DMM will measure the signals received. The entire meas...

Measurement Fundamentals This section explains how the HP 34970A makes measurements anddiscusses the most common sources of error related to these measurements. The Internal DMM The internal DMM provides a universal input front-end for measuring a variety of transducer types without the need for add...

Rejecting Power-Line Noise Voltages A desirable characteristic of an integrating analog-to-digital (A/D) converter is its ability to rejectspurious signals. Integrating techniques reject power-line related noisepresent with dc signals on the input. This is called normal mode rejection or NMR . Norma...

Temperature Measurements A temperature transducer measurement is typically either a resistanceor voltage measurement converted to an equivalent temperature bysoftware conversion routines inside the instrument. The mathematicalconversion is based on specific properties of the various transducers.The ...

To make a more accurate measurement, you should extend the coppertest leads of the internal DMM closer to the measurement and hold the connections to the thermocouple at the same temperature. This circuit will give accurate temperature measurements. However,it is not very convenient to make two ther...

T/C Type Pos (+) Lead Neg (-) Lead Temperature Range Probe Accuracy Comments B U.S. British DIN Japanese French Platinum-30% Rhodium Gray N/A Red Red N/A Platinum-60% Rhodium Red N/A Gray Gray N/A 250 ° C - 1820 ° C ± 0.5 ° C High Temperature. Beware of contamination.Do not insert in metal tubes. J ...

Sources of Error in Thermocouple Measurements Reference Junction Error A thermocouple is typically formed by welding or soldering two wires together to make the junction. Solderingintroduces a third metal into the junction. Provided that both sides ofthe thermocouple are at the same temperature, the...

Shunt Impedance The insulation used for thermocouple wire and extension wire can be degraded by high temperatures or corrosiveatmospheres. These breakdowns appear as a resistance in parallel withthe thermocouple junction. This is especially apparent in systems usinga small gauge wire where the serie...

DC Voltage Measurements To make a useful dc meter, a “front-end” is required to condition theinput before the analog-to-digital conversion. Signal conditioningincreases the input resistance, amplifies small signals, and attenuateslarge signals to produce a selection of measuring ranges. Signal Condi...

Sources of Error in DC Voltage Measurements Common Mode Rejection Ideally, the internal DMM is completely isolated from earth-referenced circuits. However, there is finiteresistance and capacitance between the input LO terminal and earth ground. If the input terminals are both driven by an earth-ref...

Loading Errors Due to Input Resistance Measurement loading errors occur when the resistance of the device-under-test ( DUT ) is an appreciable percentage of the instrument’s own input resistance.The diagram below shows this error source. Where: V s = Ideal DUT voltage R s = DUT source resistance R i...

Loading Errors Due to Input Bias Current The semiconductor devices used in the input circuits of the internal DMM have slight leakage currents called bias currents . The effect of the input bias current is a loading error at the internal DMM ’s input terminals. The leakage current will approximately...

AC Voltage Measurements The main purpose of an ac “front end” is to change an ac voltage inputinto a dc voltage which can be measured by the ADC . Signal Conditioning for AC Measurements Input signal conditioning for ac voltage measurements includes both attenuation andamplification. An input coupli...

Making High-Speed AC Measurements The internal DMM ’s ac voltage and ac current functions implement three low-frequencyfilters. These filters allow you to trade-off low frequency accuracy forfaster scanning speed. The fast filter settles in 0.12 seconds and is useful for measurements above 200 Hz. T...

Sources of Error in AC Voltage Measurements Many of the errors associated with dc voltage measurements also applyto ac voltage measurements. Additional errors unique to ac voltagemeasurements are described in this section. Crest Factor Errors (non-sinusoidal inputs) A common misconception is that “s...

Example: Calculating Measurement Error Calculate the approximate measurement error for a pulse train inputwith a crest factor of 3 and a fundamental frequency of 20 kHz.The internal DMM is set to the 1 V range. For this example, use the 90-day accuracy specifications of ± (0.05% of reading + 0.04% o...

AC Loading Errors In the ac voltage function, the input of the internal DMM appears as a 1 M Ω resistance in parallel with 150 pF of capacitance. The cabling that you use to connect signals to theinstrument will also add additional capacitance and loading. The tablebelow shows the approximate input ...

Measurements Below Full Scale You can make the most accurate ac measurements when the internal DMM is at full scale of the selected range. Autoranging occurs at 10% and 120% of full scale. This enablesyou to measure some inputs at full scale on one range and 10% of fullscale on the next higher range...

Current Measurements Current measurements are allowed only on the HP 34901A module. An ammeter senses the current flowing through its input connections – approximating a short circuit between its input terminals. An ammetermust be connected in series with the circuit or device being measuredsuch tha...

Sources of Error in DC Current Measurements When you connect the internal DMM in series with a test circuit to measure current, a measurement error is introduced. The error iscaused by the DMM ’s series burden voltage . A voltage is developed across the wiring resistance and current shunt resistance...

Resistance Measurements An ohmmeter measures the dc resistance of a device or circuit connectedto its input. Resistance measurements are performed by supplying aknown dc current to an unknown resistance and measuring thedc voltage drop. The internal DMM offers two methods for measuring resistance: 2...

The 4-wire ohms method is used in systems where lead resistances canbecome quite large and variable and in automated test applicationswhere cable lengths can be quite long. The 4-wire ohms method has theobvious disadvantage of requiring twice as many switches and twice asmany wires as the 2-wire met...

Offset Compensation Most connections in a system use materials that produce small dc voltages due to dissimilar metal-to-metal contact(thermocouple effect) or electrochemical batteries ( for a description of the thermocouple effect, see page 340 ). These dc voltages also add errors to resistance mea...

Sources of Error in Resistance Measurements External Voltages Any voltages present in the system cabling or connections will affect a resistance measurement. The effects of some ofthese voltages can be overcome by using offset compensation ( as described on the previous page ). Settling Time Effects...

Strain Gage Measurements Although the instrument does not directly support strain measurements,you can measure a strain gage using a 4-wire resistance measurementwith scaling. However, HP BenchLink Data Logger software has built-in strain gage measurement capability. When a force is applied to a bod...

For more information on strain gages, refer to “Practical Strain GageMeasurements” (HP Application Note 290-1). This application note isalso available on the HP Website in the Test and Measurement section(www.hp.com). Strain Sensors The metal foil resistance strain gage is by far the most widely use...

Making Strain Gage Measurements A Wheatstone bridge is commonly used to enable instruments with low-sensitivity measuringcapabilities to measure small resistance changes common in strainmeasurements. Instruments with high-resolution resistance measuringcapabilities, like the HP 34970A internal DMM ,...

Frequency and Period Measurements The internal DMM uses a reciprocal counting technique to measure frequency and period. This method generates constant measurementresolution for any input frequency. The internal DMM ’s ac voltage measurement section performs input signal conditioning for frequencyan...

Sources of Error in Frequency and Period Measurements The internal DMM ’s ac voltage measurement section performs input signal conditioning. All frequency counters are susceptible to errorswhen measuring low-voltage, low-frequency signals. The effects of bothinternal noise and external noise pickup ...

Low-Level Signal Multiplexing and Switching Low-level multiplexers are available in the following types: one-wire , 2-wire , and 4-wire . The following sections in this chapter describe each type of multiplexer. The following low-level multiplexer modules areavailable with the HP 34970A. • HP 34901A...

One-Wire (Single-Ended) Multiplexers On the HP 34908A multiplexer, all of the 40 channels switch the HI input only, with a common LO for the module. The module also provides a thermocouple reference junction for making thermocouple measurements (for more information on the purpose of an isothermal b...

Four-Wire Multiplexers You can make 4-wire ohms measurements using the HP 34901A andHP 34902A multiplexers. For a 4-wire ohms measurement, the channelsare divided into two independent banks by opening the bank relay. For 4-wire measurements, the instrument automatically pairs channel n with channel ...

Signal Routing and Multiplexing When used stand-alone for signal routing (not scanning or connected tothe internal DMM ), multiple channels on the HP 34901A and HP 34902A multiplexers can be closed at the same time. You must be careful thatthis does not create a hazardous condition (for example, con...

Sources of Error in Multiplexing and Switching Noise can be coupled inside a switch by the drive circuitry, by switchthermal EMF s, or by coupling among signal paths. Noise can also be generated outside the network and conducted or coupled into the switch.Although noise problems apply to the entire ...

Actuators and General-Purpose Switching The HP 34903A Actuator provides 20 independent, isolated SPDT ( single-pole, double-throw ) or Form C switches. This module offers simple on-off switching which you can use to control power devices orfor custom switching applications. For example, you can use ...

Snubber Circuits Whenever a relay contact opens or closes, electrical breakdown orarching can occur between the contacts. This can cause high-frequencynoise radiation, voltage and current surges, and physical damage to therelay contacts. A breadboard area is provided on the HP 34903A to implement cu...

The maximum value for R p is usually made equal to the load resistance R L . Therefore, the limits on R p can be stated as: V I max < R p < R L Note that the actual value of the current (I o ) in a circuit is determined by the equation: I o = V R L Where V is the peak value of the source volta...

Using Attenuators Provisions have been made on the HP 34903A circuit board forinstalling simple attenuators or filter networks. An attenuator iscomposed of two resistors that act as a voltage divider. A typicalattenuator circuit is shown below. To select the attenuator components, use the following ...

Matrix Switching A matrix switch connects multiple inputs to multiple outputs andtherefore offers more switching flexibility than a multiplexer. Use amatrix for switching low-frequency (less than 10 MHz) signals only.A matrix is arranged in rows and columns. For example, a simple 3x3matrix could be ...

Combining Matrices You can combine two or more matrix switches to provide more complexswitching. For example, the HP 34904A provides a 4-row by 8-columnmatrix. You can combine two of these modules as either a 4-row by16-column matrix or an 8-row by 8-column matrix. An 8x8 matrix isshown below. 8 Row...

RF Signal Multiplexing A special type of multiplexer is the RF multiplexer. This type of multiplexer uses special components to maintain a 50 Ω or 75 Ω impedance in the signal line being switched. In a test system, these switches are oftenused to route a test signal from a signal source to the devic...

Sources of Error in RF Switching Impedance mismatching can cause a variety of errors in an RF multiplexing system. These errors can cause distorted waveforms,overvoltage, or undervoltage conditions. To minimize RF impedance mismatching: • Use the correct cable and connector for the circuit impedance...

Multifunction Module Digital Input The HP 34907A module has two non-isolated 8-bit input/output portswhich you can use for reading digital patterns. • You can read the live status of the bits on the port or you canconfigure a scan to include a digital read. • You can generate an alarm when a specifi...

Digital Output The HP 34907A module has two non-isolated 8-bit input/output portswhich you can use for outputting digital patterns. You can combine thetwo ports to output a 16-bit word. A simplified diagram of a singleoutput bit is shown below. • Each output bit is capable of directly driving up to ...

Using an External Pull-Up In general, an external pull-up is required only when you want to setthe output “high” value greater than TTL levels. For example, to use a +12V external power supply, the value of the external pull-up resistor iscalculated as follows: V cc = 12 Vdc I max = I out low x safe...

Totalizer The HP 34907A module has a 26-bit totalizer which can count pulses ata 100 kHz rate. You can manually read the totalizer count or you canconfigure a scan to read the count. • You can configure the totalizer to count on the rising edge or fallingedge of the input signal. • Using the hardwar...

• You can control when the totalizer actually records counts by providinga gate signal ( G and G terminals on the module). A TTL high signal applied to the “ G ” terminal enables counting and a low signal disables counting. A TTL low signal applied to the “ G ” terminal enables counting and a high s...

DAC Errors The output of a DAC varies with temperature. If possible, you should operate the instrument at a stable temperature and as close as possibleto the calibration temperature of the DAC for greater accuracy. The output of a DAC also exhibits two other types of errors: differential error and i...

Relay Life and Preventative Maintenance The HP 34970A Relay Maintenance System automatically counts the cycles on each relay in the instrument and stores the total count innon-volatile memory on each switch module. Use this feature to trackrelay failures and predict system maintenance requirements. ...

Relay Life As a relay is used, the contacts begin to wear and the resistance of theclosed contacts increases. The initial contact resistance of a relay istypically 50 m Ω (plus lead resistance). When the contact resistance exceeds 20 to 50 times its initial value, the contact resistance becomesvery ...

9 Specifications • DC, Resistance, and Temperature Accuracy Specifications, on page 404 • DC Measurement and Operating Characteristics, on page 405 • AC Accuracy Specifications, on page 406 • AC Measurement and Operating Characteristics, on page 407 • Measurement Rates and System Characteristics, on...

DC, Resistance, and Temperature Accuracy Specifications ± ( % of reading + % of range ) [1] Includes measurement error, switching error, and transducer conversion error Function Range [3] Test Current or Burden Voltage 24 Hour [2] 23 °C ± 1 °C 90 Day 23 °C ± 5 °C 1 Year 23 °C ± 5 °C Temperature Coef...

DC Measurement and Operating Characteristics DC Measurement Characteristics [1] DC VoltageMeasurement Method: A/D Linearity: Input Resistance: 100 mV, 1 V, 10 V ranges 100 V, 300 V ranges Input Bias Current: Input Protection: Continuously Integrating, Multi-slope III A/D Converter0.0002% of reading ...

AC Accuracy Specifications ± ( % of reading + % of range ) [1] Includes measurement error, switching error, and transducer conversion error Function Range [3] Frequency 24 Hour [2] 23 °C ± 1 °C 90 Day 23 °C ± 5 °C 1 Year 23 °C ± 5 °C Temperature Coefficient /°C 0 °C – 18 °C 28 °C – 55 °C True RMSAC ...

AC Measurement and Operating Characteristics AC Measurement Characteristics [1] True RMS AC Voltage Measurement Method: Crest Factor:Additional Crest FactorErrors (non-sinewave): [2] AC Filter Bandwidth: Slow Medium FastInput Impedance: Input Protection: AC-coupled True RMS – measuresthe ac componen...

Measurement Rates and System Characteristics Single Channel Measurement Rates [1] [2] FunctionDCV, 2-Wire Ohms: Thermocouple: RTD, Thermistor: ACV: Frequency, Period: Resolution 6 1 ⁄ 2 (10 PLC) 5 1 ⁄ 2 (1 PLC) 4 1 ⁄ 2 (0.02 PLC) 0.1 ° C (1 PLC) (0.02 PLC) 0.01 ° C (10 PLC) 0.1 ° C (1 PLC) 1 ° C (0....

Module Specifications HP 34901A, 34902A, 34908A, 34903A, 34904A Multiplexer Actuator Matrix General 34901A 34902A 34908A 34903A 34904A Number of Channels 20+2 16 40 20 4x8 2/4 wire 2/4 wire 1 wire SPDT 2 wire Connects to Internal DMM Yes Yes Yes No No Scanning Speed 60 ch/s 250 ch/s 60 ch/s Open/Clo...

Typical AC Performance Graphs HP 34905A, 34906A Insertion Loss (50 W ) Insertion Loss (75 W ) VSWR (75 W ) Crosstalk (50 W ) Crosstalk (75 W ) Direct to ModuleUsing provided adapter cables VSWR (50 W ) 9 Chapter 9 SpecificationsTypical AC Performance Graphs 411

Module Specifications HP 34907A Digital Input / Output Port 1, 2:V in (L): V in (H): V out (L): V out (H): V out (H) Max: Alarming: Speed LatencyRead/Write Speed: 8 Bit, input or output, non-isolated< 0.8V (TTL)> 2.0V (TTL)< 0.8V @ Iout = - 400 mA> 2.4V @ Iout = 1 mA< 42V with externa...

Product and Module Dimensions 91.9 315.6 Module TOP All dimensions are shown in millimeters. 103.6 mm 254.4 mm 374.0 mm 348.3 mm 212.6 mm 88.5 mm 9 Chapter 9 SpecificationsProduct and Module Dimensions 413

To Calculate Total Measurement Error Each specification includes correction factors which account for errorspresent due to operational limitations of the internal DMM . This section explains these errors and shows how to apply them to your measurements.Refer to “Interpreting Internal DMM Specificati...

Understanding the “ % of range ” Error The range error compensates for inaccuracies that result from the function and range you select.The range error contributes a constant error, expressed as a percent ofrange, independent of the input signal level. The following table shows the range error applie...

Interpreting Internal DMM Specifications This section is provided to give you a better understanding of theterminology used and will help you interpret the internal DMM ’s specifications. Number of Digits and Overrange The “number of digits” specification is the most fundamental, andsometimes, the m...

Resolution Resolution is the numeric ratio of the maximum displayed value dividedby the minimum displayed value on a selected range. Resolution isoften expressed in percent, parts-per-million (ppm), counts, or bits.For example, a 6 1 ⁄ 2 -digit multimeter with 20% overrange capability can display a ...

24-Hour Accuracy The 24-hour accuracy specification indicates the internal DMM ’s relative accuracy over its full measurement range for short time intervals andwithin a stable environment. Short-term accuracy is usually specifiedfor a 24-hour period and for a ± 1 °C temperature range. 90-Day and 1-Y...

Configuring for Highest Accuracy Measurements The measurement configurations shown below assume that the internal DMM is in its Factory Reset state. It is also assumed that manual ranging is enabled to ensure proper full scale range selection. DC Voltage, DC Current, and Resistance Measurements : • ...

Index Warnings HP 34901A, 165 HP 34902A, 167 HP 34903A, 169 HP 34904A, 171 HP 34908A, 176“ 1 ⁄ 2 ” digit, 100, 416 4W annunciator, 4 50 Ω RF switching, 390 75 Ω RF switching, 390 *CLS command, 291 *ESE command, 288 *ESR? command, 288 *IDN? command, 265 *OPC command, 279, 291 *OPC? command, 279 *PSC ...

autozero definition, 105 vs. integration time, 105average responding error, 360average, during scan, 75AWG, wire gauge size, 336 B “B” (Mx+B scaling offset), 119backplane relays, 164, 166, 276, 383bandwidth (ac) ac current, 116 ac voltage, 114 vs. channel delays, 89bank switch, 164, 166, 176, 383bat...

DECLARATION OF CONFORMITY according to ISO / IEC Guide 22 and EN 45014 Manufacturer’s Name: Hewlett-Packard CompanyLoveland Manufacturing Center Manufacturer’s Address: 815 14th Street S.W.Loveland, Colorado 80537 U.S.A. declares, that the product Product Name: Data Acquisition / Switch Unit Model N...