Agilent-technologies 34401A Manuel d'utilisateur

Agilent TechnologiesAgilent 34401A 6 ½ Digit MultimeterUser’s Guide

Display Annunciators Adrs Rmt Man Trig Hold Mem Ratio Math ERRORRear Shift 4W Turns on during a measurement. Multimeter is addressed to listen

Programming Language Selection You can select one of three languages to program the multimeter fromthe selected remote interface. The language is SC

Calibration OverviewThis section gives a brief introduction to the calibration features of themultimeter. For a more detailed discussion of the calibr

CalibrationSecurity (continued) To Unsecure for Calibration You can unsecure the multimeterfor calibration either from the front panel or remote int

To Secure Against Calibration You can secure the multimeteragainst calibration either from the front panel or remote interface.The multimeter is sec

CalibrationSecurity (continued) To Change the Security Code To change the security code, you mustfirst unsecure the multimeter, and then enter a new

Calibration Message You can use the calibration message feature to record calibrationinformation about your multimeter. For example, you can store suc

Operator Maintenance This section describes how to replace the power-line and current fuses.If you need additional information about replacing parts o

Power-On and Reset State Measurement Configuration AC Filter Autozero • Continuity Threshold Function Input Resistance Integration Time R

102

4Remote Interface Reference 4

The Rear Panel at a Glance 1 Chassis Ground 2 Power-Line Fuse-Holder Assembly 3 Power-Line Voltage Setting 4 Front and Rear Current Input

Remote Interface Reference • Command Summary, starting on page 105• Simplified Programming Overview, starting on page 112• The MEASure? and CONFi

Command Summary This section summarizes the SCPI (Standard Commands forProgrammable Instruments) commands available to program themultimeter. Refer to

Default parameters are shown in bold. Measurement Configuration Commands (see page 121 for more information)[SENSe:] FUNCtion "VOLTage:DC"

Measurement Configuration Commands (continued)[SENSe:] VOLTage:DC:RESolution {<resolution>|MINimum|MAXimum} VOLTage:DC:RESolution? [MINimum|M

Math Operation Commands (see page 124 for more information)CALCulate :FUNCtion {NULL|DB|DBM|AVERage|LIMit} :FUNCtion? :STATe {OFF|ON} :STATe?CAL

Triggering Commands (see page 127 for more information)INITiateREAD?TRIGger :SOURce {BUS|IMMediate |EXTernal} :SOURce?TRIGger :DELay {<seconds

Default parameters are shown in bold. Status Reporting Commands (see page 144 for more information)SYSTem:ERRor?STATus :QUEStionable:ENABle <enabl

RS-232 Interface Commands (see page 148 for more information)SYSTem:LOCal SYSTem:REMoteSYSTem:RWLock IEEE-488.2 Common Commands (see page 169 for

Simplified Programming Overview You can program the multimeter to take measurements from the remoteinterface using the following simple seven-step seq

Using the MEASure? Command The easiest way to program the multimeter for measurements is byusing the MEASure? command. However, this command does not

In This Book Quick Start Chapter 1 prepares the multimeter for use and helps youget familiar with a few of its front-panel features.Front-Panel Men

Using the range and resolution Parameters With the MEASure? and CONFigure commands, you can select themeasurement function, range, and resolution all

Caution If you send two query commands without reading the response from thefirst, and then attempt to read the second response, you may receive somed

CONFigureExampleThe following program segment shows how to use the READ? commandwith CONFigure to make an externally-triggered measurement.The program

The MEASure? and CONFigure CommandsSee also “Measurement Configuration,” starting on page 51 in chapter 3.• For the range parameter, MIN selects the l

MEASure:CURRent:AC? {<range>|MIN|MAX|DEF},{<resolution>|MIN|MAX|DEF} Preset and make an ac current measurement with the specified rangeand

CONFigure:VOLTage:DC {<range>|MIN|MAX|DEF},{<resolution>|MIN|MAX|DEF}Preset and configure the multimeter for dc voltage measurements witht

CONFigure:FREQuency {<range>|MIN|MAX|DEF},{<resolution>|MIN|MAX|DEF} Preset and configure a frequency measurement with the specified range

Measurement Configuration Commands See also “Measurement Configuration,” starting on page 51 in chapter 3.FUNCtion "<function>"Select

<function>:RESolution {<resolution>|MINimum|MAXimum}Select the resolution for the specified function (not valid for frequency,period, or r

[SENSe:]DETector:BANDwidth {3|20|200|MINimum|MAXimum} Specify the lowest frequency expected in the input signal. The multimeterselects the slow, mediu

ContentsChapter 1 Quick Start To Prepare the Multimeter for Use 13If the Multimeter Does Not Turn On 14To Adjust the Carrying Handle 16To Measure

Math Operation Commands See also “Math Operations,” starting on page 63 in chapter 3.There are five math operations available, only one of which can b

CALCulate:AVERage:MINimum? Read the minimum value found during a min-max operation. Themultimeter clears the value when min-max is turned on, when po

CALCulate:DBM:REFerence {<value>|MINimum|MAXimum} Select the dBm reference value. Choose from: 50, 75, 93, 110, 124, 125,135, 150, 250, 300, 50

Triggering See also “Triggering,” starting on page 71 in chapter 3.The multimeter’s triggering system allows you to generate triggerseither manually

Agilent 34401A Triggering System Delay Idle State Wait-for- Trigger State Measurement Sample Sample Count ≠ 1Trigger Count ≠ 1Initiate T

The Wait-for-Trigger StateAfter you have configured the multimeter and selected a trigger source,you must place the multimeter in the wait-for-trigger

Triggering Commands See also “Triggering,” starting on page 71 in chapter 3.INITiateChange the state of the triggering system from the “idle” state to

TRIGger:DELay {<seconds>|MINimum|MAXimum}Insert a trigger delay between the trigger signal and each samplethat follows. If you do not specify a

System-Related CommandsSee also “System-Related Operations,” starting on page 84 in chapter 3. FETCh?Transfer readings stored in the multimeter’s inte

SYSTem:BEEPerIssue a single beep immediately. SYSTem:BEEPer:STATe {OFF|ON} Disable or enable the front-panel beeper. [Stored in non-volatile memory]

Chapter 3 Features and Functions (continued) Math Operations Min-Max Operation 64 Null (Relative) Operation 65 dB Measurements 67 dBm Measurements

The SCPI Status Model All SCPI instruments implement status registers in the same way.The status system records various instrument conditions in three

SCPI Status System 4Chapter 4 Remote Interface Reference The SCPI Status Model 135

The Status ByteThe status byte summary register reports conditions from other statusregisters. Query data that is waiting in the multimeter’s output b

Using Service Request (SRQ) and Serial POLL You must configure your bus controller to respond to the IEEE-488service request (SRQ) interrupt to use th

Using *STB? to Read the Status Byte The *STB? (status byte query) command is similar to a serial poll exceptit is processed like any other instrument

How to Use the Message Available Bit (MAV)You can use the status byte “message available” bit (bit 4) to determinewhen data becomes available to read

The Standard Event Register The standard event register reports the following types of instrumentevents: power-on detected, command syntax errors, com

The standard event register is cleared when:• You send a *CLS (clear status) command.• You query the event register using the *ESR? (event status regi

The Questionable Data Register The questionable data register provides information about the qualityof the multimeter’s measurement results. Overload

The questionable data event register is cleared when:• You execute a *CLS (clear status) command.• You query the event register using STATus:QUEStiona

Chapter 4 Remote Interface Reference Command Summary 105Simplified Programming Overview 112The MEASure? and CONFigure Commands 117Measurement Co

Status Reporting Commands SYSTem:ERRor?Query the multimeter’s error queue. Up to 20 errors can be stored in thequeue. Errors are retrieved in first-in

*ESR? Query the Standard event register. The multimeter returns a decimalvalue which corresponds to the binary-weighted sum of all bits set in theregi

Calibration CommandsSee “Calibration Overview” starting on page 95 for an overview of thecalibration features of the multimeter. For a more detailed d

CALibration:STRing <quoted string> Record calibration information about your multimeter. For example,you can store such information as the last

RS-232 Interface Configuration See also “Remote Interface Configuration,” on page 91 in chapter 3.You connect the multimeter to the RS-232 interface u

RS-232 Data Frame FormatA character frame consists of all the transmitted bits that make up asingle character. The frame is defined as the characters

DB-9 Serial Connection If your computer or terminal has a 9-pinserial port with a male connector, use the null-modem cable includedwith the Agilent 3

DTR / DSR Handshake ProtocolThe multimeter is configured as a DTE (Data Terminal Equipment) deviceand uses the DTR (Data Terminal Ready) and DSR (Data

The multimeter holds the DTR line FALSE while output is suspended.A form of interface deadlock exists until the controller asserts the DSRline TRUE to

RS-232 Interface Commands Use the front-panel I/O MENU to select the baud rate, parity, and number of data bits (see pages 163 and 164 for more infor

Chapter 7 Measurement Tutorial Thermal EMF Errors 199Loading Errors (dc volts) 199Leakage Current Errors 199Rejecting Power-Line Noise Voltages

An Introduction to the SCPI Language SCPI (Standard Commands for Programmable Instruments) is anASCII-based instrument command language designed for t

Command Format Used in This ManualThe format used to show commands in this manual is shown below: VOLTage:DC:RANGe {<range>|MINimum|MAXimum}

Command Separators A colon ( : ) is used to separate a command keyword from a lower-levelkeyword. You must insert a blank space to separate a paramete

Querying Parameter SettingsYou can query the current value of most parameters by adding aquestion mark ( ? ) to the command. For example, the followin

IEEE-488.2 Common CommandsThe IEEE-488.2 standard defines a set of common commands thatperform functions like reset, self-test, and status operations.

Boolean Parameters Boolean parameters represent a single binarycondition that is either true or false. For a false condition, the multimeterwill acce

Using Device Clear to Halt MeasurementsDevice clear is an IEEE-488 low-level bus message which can be used tohalt measurements in progress. Different

To Set the GPIB Address Each device on the GPIB (IEEE-488) interface must have a uniqueaddress. You can set the multimeter’s address to any value betw

To Select the Remote Interface The multimeter is shipped with both an GPIB (IEEE-488) interfaceand an RS-232 interface. Only one interface can be ena

To Set the Baud Rate You can select one of six baud rates for RS-232 operation. The rate is setto 9600 baud when the multimeter is shipped from the f

1Quick Start 1

To Set the Parity You can select the parity for RS-232 operation. The multimeter isconfigured for even parity with 7 data bits when shipped from thef

To Select the Programming Language You can select one of three languages to program the multimeterfrom the selected remote interface. The language i

Alternate Programming Language Compatibility You can configure the Agilent 34401A to accept and execute thecommands of either the Agilent 3478A multim

Fluke 8840A/8842A Language SettingAll Fluke 8840A or 8842A commands are accepted and executed bythe Agilent 34401A with equivalent operations, with th

SCPI Compliance Information The following commands are device-specific to the Agilent 34401A. Theyare not included in the 1991.0 version of the SCPI s

IEEE-488 Compliance Information IEEE-488.2 Common Commands *CLS *ESE <enable value> *ESE?*ESR?*IDN?*OPC*OPC?*PSC {0|1} *PSC?*RST*SRE <enable

170

5Error Messages 5

Error Messages • Errors are retrieved in first-in-first-out (FIFO) order. The firsterror returned is the first error that was stored. When you havere

Execution Errors -101 Invalid character An invalid character was found in the command string. You may haveinserted a character such as #, $, or % in

Quick Start One of the first things you will want to do with your multimeter is tobecome acquainted with its front panel. We have written the exerc

-112 Program mnemonic too long A command header was received which contained more than themaximum 12 characters allowed. Example: CONFIGURATION:VOL

-151 Invalid string data An invalid character string was received. Check to see if you haveenclosed the character string in single or double quotes

-221 Settings conflict This error can be generated in one of the following situations:• You sent a CONFigure or MEASure command with autorange enabl

-350 Too many errors The error queue is full because more than 20 errors have occurred. No additional errors are stored until you remove errors fro

501 Isolator UART framing error 502 Isolator UART overrun error 511 RS-232 framing error 512 RS-232 overrun error 513 RS-232 parity error 514 Command

Self-Test Errors The following errors indicate failures that may occur during a self-test.Refer to the Service Guide for more information.601 Front pa

616 DC current sense failed 617 Ohms 100 uA source failed 618 DC high voltage attenuator failed 619 Ohms 1 mA source failed 620 AC rms zero failed 621

703 Invalid secure code An invalid calibration security code was received when attempting tounsecure or secure the multimeter. You must use the same s

725 500V DC correction out of range 730 Precharge DAC convergence failed 731 A/D turnover correction out of range 732 AC flatness DAC convergence fail

6Application Programs 6

To Prepare the Multimeter for Use The following steps help you verify that the multimeter is ready for use.1 Check the list of supplied items.Verify

Application Programs This chapter contains several remote interface application programsto help you develop programs for your measurement applica

Using MEASure? for a Single Measurement The following example uses the MEASure? command to make a singleac current measurement. This is the easiest wa

Using CONFigure with a Math Operation The following example uses CONFigure with the dBm math operation.The CONFigure command gives you a little more p

REM $Include "QBSetup" DEV&=722 INFO1$="*RST" LENGTH1%=LEN(INFO1$) INFO2$="*CLS" LENGTH2%=LEN(INFO2$) INFO3$=&quo

Using the Status Registers The following example shows how you can use the multimeter’s statusregisters to determine when a command sequence is comple

GPIB Operation Using BASIC (continued) 280 Task=1290 WHILE Task=1300 DISP "Taking Readings"310 WAIT .5320 DISP ""330

GPIB Operation Using QuickBASIC REM $Include "QBSetup" ISC&=7DEV&=722 INFO1$="*RST" LENGTH1%=LEN(INFO1$) INFO2$="*

Call IOCLEAR(DEV&) Call IOOUTPUTS(DEV&, INFO1$, LENGTH1%) Call IOOUTPUTS(DEV&, INFO2$, LENGTH2%) ON PEN GOSUB RESULTSPEN ONCall IOPEN(ISC&

RS-232 Operation Using QuickBASIC The following example shows how to send command instructions andreceive command responses over the RS-232 interface

RS-232 Operation Using Turbo C The following example shows how to program an AT personal computerfor interrupt-driven COM port communications. SCPI co

ii 34401A User’s GuideNotices© Agilent Technologies, Inc. 1991 - 2007No part of this manual may be reproduced in any form or by any means (including e

If the Multimeter Does Not Turn OnUse the following steps to help solve problems you might encounterwhen turning on the multimeter. If you need more h

#define IRQ4_int 0xC /* IRQ4 interrupt vector number */ #define IRQ4_enab 0xEF /* IRQ4 interrupt controller enable mask */#defin

printf("\nEnter command string:\n"); gets(command); strcat(command,"\n"); /* SCPI requires line feed */ if(comman

void interrupt int_char_in(void) { enable(); /* Enable hardware interrupts */ if(int_buf_count < INT_BUF_size) { *int_buf_in++

7Measurement Tutorial 7

Measurement Tutorial The Agilent 34401A is capable of making highly accuratemeasurements. In order to achieve the greatest accuracy, you must takethe

Loading Errors (dc volts) Measurement loading errors occur when the resistance of the device-under-test (DUT) is an appreciable percentage of the mult

Rejecting Power-Line Noise Voltages A desirable characteristic of integrating analog-to-digital (A/D) convertersis their ability to reject spurious si

Common Mode Rejection (CMR) Ideally, a multimeter is completely isolated from earth-referenced circuits.However, there is finite resistance between th

Noise Caused by Ground Loops When measuring voltages in circuits where the multimeter and thedevice-under-test are both referenced to a common earth g

Resistance MeasurementsThe Agilent 34401A offers two methods for measuring resistance:2-wire and 4-wire ohms. For both methods, the test current flows

See rear panel for proper fuse rating.Agilent Part Number: 2110-0817 (250 mAT) 100, 120, 220 (230) or 240 Vac 1 Rem

Removing Test Lead Resistance Errors To eliminate offset errors associated with the test lead resistance in2-wire ohms measurements, follow the steps

Errors in High Resistance MeasurementsWhen you are measuring large resistances, significant errors can occurdue to insulation resistance and surface c

True RMS AC Measurements True RMS responding multimeters, like the Agilent 34401A, measurethe “heating” potential of an applied voltage. Unlike an “av

An ac-coupled true RMS measurement is desirable in situations whereyou are measuring small ac signals in the presence of large dc offsets.For example,

Crest Factor(continued)You can estimate the measurement error due to signal crest factor asshown below: Total Error = Error (sine) + Error (crest fac

Loading Errors (ac volts) In the ac voltage function, the input of the Agilent 34401A appears as a1 MΩ resistance in parallel with 100 pF of capacita

Measurements Below Full ScaleYou can make the most accurate ac measurements when the multimeteris at full scale of the selected range. Autoranging occ

Low-Level Measurement ErrorsWhen measuring ac voltages less than 100 mV, be aware that thesemeasurements are especially susceptible to errors introduc

Common Mode ErrorsErrors are generated when the multimeter’s input LO terminal is drivenwith an ac voltage relative to earth. The most common situatio

Frequency and Period Measurement ErrorsThe multimeter uses a reciprocal counting technique to measurefrequency and period. This method generates const

To Adjust the Carrying HandleTo adjust the position, grasp the handle by the sides and pull outward.Then, rotate the handle to the desired position.

Making High-Speed AC Measurements The multimeter’s ac voltage and ac current functions implement threedifferent low-frequency filters. These filters a

8Specifications 8

DC Characteristics DC Characteristics Accuracy Specifications ± ( % of reading + % of range ) [ 1 ] Function Range [ 3 ]Test Current or Burden Vo

DC Characteristics Function DCV, DCI, andResistanceDigits 61⁄2 61⁄2 51⁄2 51⁄2 41⁄2 Readings/s 0.6 (0.5) 6 (5) 60 (50) 300 1000 A

AC Characteristics AC Characteristics Accuracy Specifications ± ( % of reading + % of range ) [ 1 ]Function Range [ 3 ] Frequency24 Hour [ 2 ]23°C

AC Characteristics Measurement Noise Rejection [ 8 ] AC CMRRTrue RMS AC Voltage Measurement Method: Crest Factor:AC Filter Bandwidth: Slow Medium

Frequency and Period CharacteristicsFrequency and Period Characteristics Accuracy Specifications ± ( % of reading ) [ 1 ]Function Range [

Frequency and Period CharacteristicsFrequency and Period Measurement Method: Voltage Ranges:Gate Time: Reciprocal-counting technique.AC-coupled input

General Information General Information General Specifications Power Supply: Power Line Frequency:Power Consumption:Operating Environment:Storage Envi

Product Dimensions348. 3 mm88. 5 mm212. 6 mm261.1 mm379.4 mm103.8 mmTOPProduct DimensionsAll dimensions areshown in millimeters. 8Chapter 8 Specifica

To Measure Voltage Ranges: 100 mV, 1 V, 10 V, 100 V, 1000 V (750 Vac)Maximum resolution: 100 nV (on 100 mV range)AC technique: true RMS, ac-

To Calculate Total Measurement Error Each specification includes correction factors which account for errorspresent due to operational limitations of

Understanding the “ % of range ” Error The range error compensatesfor inaccuracies that result from the function and range you select.The range error

Interpreting Multimeter Specifications This section is provided to give you a better understanding of the terminologyused and will help you interpret

Resolution Resolution is the numeric ratio of the maximum displayed value dividedby the minimum displayed value on a selected range. Resolution isofte

Transfer Accuracy Transfer accuracy refers to the error introduced by the multimeterdue to noise and short-term drift. This error becomes apparent whe

Configuring for Highest Accuracy Measurements The measurement configurations shown below assume that themultimeter is in its power-on or reset state.

230

Index“1⁄2” digit, 21, 54 2-wire ohmsSee two-wire ohms34398A Cable Kit, 14934399A Adapter Kit, 1493478A compatibility, 16634812A BenchLink Software, 14

DDATA:FEED, 65, 126, 130DATA:FEED?, 65, 126, 130DATA:POINts?, 84, 133data logging to printer, 91, 160data types (SCPI), 158data formats, output, 159dB

Ggate time, 58GPIB (IEEE-488)addressdisplayed at power-on, 13factory setting, 91setting the, 91, 161TALK ONLY mode, 91, 160compliance information, 168

To Measure Current Ranges: 10 mA (dc only), 100 mA (dc only), 1 A , 3 AMaximum resolution: 10 nA (on 10 mA range)AC technique: true RMS, ac-co

menuexamples, 31-36overview, 3messages displayed, 30quick reference, 27-28tree diagram, 29messages displayedfront-panel, 87menu, 30message terminators

rangingautoranging, 20, 61front-panel keys, 20overload, 61, 142selecting, 20ratio (dcv:dcv) measurements connections, 44front panel, 44 math functions

status registercommands, 144description, 134diagram, 135enable register, 134event register, 134*STB?, 138, 145stop bits, 148storing readingsfunctions

To Test Continuity Test current source: 1 mAMaximum resolution: 0.1 Ω (range is fixed at 1 kohm)Beeper threshold: 1 Ω to 1000 Ω (beeps below ad

To Select a Range You can let the multimeter automatically select the range usingautoranging or you can select a fixed range using manual ranging. •

To Set the Resolution You can set the display resolution to 41⁄2, 51⁄2, or 61⁄2 digits either tooptimize measurement speed or noise rejection. In th

Front-Panel Display Formats -H.DDD,DDD EFFFFront-panel display format. 10.216,5 VDCThis is the 10 Vdc range, 51⁄2 digits are displayed. -04

To Rack Mount the Multimeter You can mount the multimeter in a standard 19-inch rack cabinet usingone of three optional kits available. Instructions

34401A User’s Guide iiiSafety InformationGeneralDo not use this product in any manner not specified by the manufacturer. The protec-tive features of t

To rack mount a single instrument, order adapter kit 5063-9240. To rack mount two instruments side-by-side, order lock-link kit 5061-9694 and

2Front-Panel Menu Operation 2

Front-Panel Menu Operation By now you should be familiar with the FUNCTION and RANGE / DIGITSgroups of front-panel keys. You should also understand

Front-Panel Menu Reference 1: AC FILTER 2: CONTINUITY 3: INPUT R 4: RATIO FUNC 5: RESOLUTION Selects the slow, medium, or fast ac filter. Sets th

1: RDGS STORE 2: SAVED RDGS 3: ERROR 4: TEST 5: DISPLAY 6: BEEP 7: COMMA 8: REVISION Enables or disables reading memory. Recalls readings stored i

A Front-Panel Menu Tutorial This section is a step-by-step tutorial which shows how to use thefront-panel menu. We recommend that you spend a few min

MESSAGES DISPLAYED DURING MENU USE TOP OF MENU You pressed while on the “menus” level; this is the top level ofthe menu and you cannot go

Menu Example 1 The following steps show you how to turn on the menu, move up ordown between levels, move across the choices on each level, and turn of

4 Move across to the BEEP command on the “commands” level.There are eight command choices available in the SYS MENU. Eachchoice on this level has a nu

Menu Example 2 The following exercise demonstrates how to use the menu recall featureas a shortcut to set the BEEP command back to its original settin

iv 34401A User’s GuideWARNINGIEC Measurement Category II. The HI and LO input terminals may be connected to mains in IEC Cate-gory II installations fo

Menu Example 3 Some commands in the menu require that you enter a numericparameter value. The following steps show you how to enter a numberin the men

5 Move down to edit the NULL VALUE parameter. The null value should be 0.0 Vdc when you come to this point in themenu for the first time. For this exa

9 Move the flashing cursor over to the “units” location.Notice that the units are flashing on the right side of the display. -200.000 mVDC10 Increase

To Turn Off the Comma Separator The multimeter can display readings on the front panel with or withouta comma separator. The following steps show how

To Make Null (Relative) Measurements Each null measurement, also called relative, is the difference between astored null value and the input signal.R

To Store Minimum and Maximum Readings You can store the minimum and maximum readings during a seriesof measurements. The following discussion shows h

To Make dB Measurements Each dB measurement is the difference between the input signal and astored relative value, with both values converted to dBm.

To Make dBm Measurements The dBm operation calculates the power delivered to a resistancereferenced to 1 milliwatt. dBm = 10 × Log10 ( reading2 / ref

To Trigger the Multimeter You can trigger the multimeter from the front panel using single triggeror auto trigger. • Auto triggering is enabled when

To Use Reading Hold The reading hold feature allows you to capture and hold a stablereading on the display. When a stable reading is detected, themul

34401A User’s Guide vIEC Measurement Category II includes elec-trical devices connected to mains at an out-let on a branch circuit. Such devices inclu

To Make dcv:dcv Ratio Measurements To calculate a ratio, the multimeter measures a dc reference voltageapplied to the Sense terminals and the voltag

The following steps show you how to select the ratio function using thefront-panel menu.1 Turn on the menu. A: MEAS MENU 2 Move down a level and th

To Use Reading Memory The multimeter can store up to 512 readings in internal memory.The following steps demonstrate how to store readings and retrie

6 Move down a level and then across to the “ON” choice. ON7 Save the change and exit the menu.Notice that the Mem (memory) annunciator turns on to in

10 Move down a level to view the first stored reading.Reading memory is automatically turned off when you go to the“parameter” level in the menu.The f

3Features and Functions 3

Features and Functions You will find that this chapter makes it easy to look up all the detailsabout a particular feature of the multimeter. Whether

Measurement Configuration This section contains information to help you configure the multimeterfor making measurements. You may never have to change

Continuity Threshold Resistance When measuring continuity, the multimeter emits a continuous tone ifthe measured resistance is less than the threshold

DC Input Resistance Normally, the multimeter’s input resistance is fixed at 10 MΩ for alldc voltage ranges to minimize noise pickup. To reduce the eff

DECLARATION OF CONFORMITYAccording to ISO/IEC Guide 22 and CEN/CENELEC EN 45014Revision: B.01 Issue Date: 18 July 2001 Document 34401A.DOCManufacturer

ResolutionResolution is expressed in terms of number of digits the multimeter canmeasure or display. You can set the resolution to 4, 5, or 6 full di

10.216,5 VDCThis is the 10 Vdc range, 51⁄2 digits are displayed. -045.23 mVDCThis is the 100 mVdc range, 41⁄2 digits are displayed. 113

Resolution (continued) • Front-Panel Operation: Select either the slow or fast mode for eachresolution setting. The default mode is 5 digits slow.

Integration Time Integration time is the period during which the multimeter’s analog-to-digital (A/D) converter samples the input signal for a measure

Integration Time(continued) • Front-Panel Operation: Integration time is set indirectly when youselect the number of digits. See the table for resolu

AutozeroWhen autozero is enabled (default), the multimeter internallydisconnects the input signal following each measurement, and takes azero reading.

Autozero (continued) The following table shows the relationship between integration time andautozero settings from the remote interface and the corres

RangingYou can let the multimeter automatically select the range usingautoranging or you can select a fixed range using manual ranging.Autoranging is

Ranging (continued) • Front-Panel Operation: Use the front-panel RANGE keys to selectautoranging or manual ranging. For frequency and periodmeasuremen

Math Operations There are five math operations available, only one of which can beenabled at a time. Each math operation performs a mathematicaloperat

Note: Unless otherwise indicated, this manual applies to all Serial Numbers.The Agilent Technologies 34401A is a 61⁄2-digit, high-performancedigital m

Min–Max Operation The min-max operation stores the minimum and maximum readingsduring a series of measurements. The multimeter then calculates theave

• Remote Interface Operation: You can use the following commands tomake min-max measurements. CALCulate:FUNCtion AVERage CALCulate:STATe {OFF|ON}

Null (Relative)(continued) • The null value is stored in the multimeter’s Null Register. There aretwo ways you can specify the null value. First, you

dB MeasurementsEach dB measurement is the difference between the input signal and astored relative value, with both values converted to dBm. dB = rea

• Remote Interface Operation: You can use the following commands tomake dB measurements. Math must be enabled before you can store avalue to the Rela

Limit TestingThe limit test operation enables you to perform pass/fail testing toupper and lower limits that you specify. Applies to all measurement f

Limit Testing (continued) • Remote Interface Operation: You can use the following commands forlimit testing. CALCulate:FUNCtion LIMit CALCulate:S

Triggering The multimeter’s triggering system allows you to generate triggerseither manually or automatically, take multiple readings per trigger,and

Agilent 34401A Triggering System Delay Idle State Wait-for- Trigger State Measurement Sample Sample Count ≠ 1Trigger Count ≠ 1Initiate T

Trigger Source Choices You must specify the source from which the multimeter will accept atrigger. From the front panel, the multimeter will accept a

The Front Panel at a Glance 1 Measurement Function keys 2 Math Operation keys 3 Single Trigger / Autotrigger / Reading Hold key4 Shift / Local k

External Triggering In the external trigger mode, the multimeterwill accept a hardware trigger applied to the Ext Trig terminal.The multimeter takes

Internal Triggering In the internal trigger mode (remote interface only),the trigger signal is always present. When you place the multimeter inthe wa

The Wait-for-Trigger StateAfter you have configured the multimeter and selected a trigger source,you must place the multimeter in the wait-for-trigger

Number of Samples Normally, the multimeter takes one reading (or sample) each time itreceives a trigger from the selected trigger source (if the multi

Number of TriggersNormally, the multimeter will accept only one trigger before returningto the “idle” trigger state. You can, however, instruct the mu

Trigger Delay You can insert a delay between the trigger signal and each sample thatfollows. This may be useful in applications where you want to al

• Front-Panel Operation (continued)To set the delay to 0 seconds, select the “parameter” level of the TRIGDELAY command. Move the flashing cursor to

Automatic Trigger Delays If you do not specify a trigger delay, the multimeter selects anautomatic delay for you. The delay is determined by functi

Reading Hold The reading hold feature allows you to capture and hold a stablereading on the front-panel display. This is especially useful in situati

Voltmeter Complete Terminal The rear-panel VM Comp (voltmeter complete) terminal provides alow-true pulse after the completion of each measurement. Vo

The Front-Panel Menu at a Glance A: MEASurement MENU 1: AC FILTER > 2: CONTINUITY > 3: INPUT R > 4: RATIO FUNC > 5: RESOLUTION

System-Related Operations This section gives information on topics such as reading memory, errors,self-test, and front-panel display control. This inf

Error Conditions When the front-panel ERROR annunciator turns on, one or morecommand syntax or hardware errors have been detected. A record of upt

Self-Test A power-on self-test occurs automatically when you turn on themultimeter. This limited test assures you that the multimeter isoperational.

Display Control To speed up your measurement rate, or for security reasons, you maywant to turn off the front-panel display. From the remote interf

Beeper Control Normally, the multimeter will emit a tone whenever certain conditionsare met from the front panel. For example, the multimeter will

Comma Separators The multimeter can display readings on the front panel with or withouta comma separator. This feature is available only from the f

SCPI Language Version Query The multimeter complies with the rules and regulations of the presentversion of SCPI (Standard Commands for Programmable

Remote Interface Configuration This section gives information on configuring the remote interface.For additional information, see chapter 4, “Remote I

Remote Interface Selection The multimeter is shipped with both an GPIB (IEEE-488) interfaceand an RS-232 interface. Only one interface can be enabled

Baud Rate Selection (RS-232) You can select one of six baud rates for RS-232 operation. The rate is setto 9600 baud when the multimeter is shipped fr