Agilent 34401A Users Guide

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Note: Unless ot h erwise ind i cated, this manual applies t o all Serial Nu m b e rs.

The Agilent Technologies 34401A is a 6

⁄

-digit, high-performance

digital multimeter. Its co m bination o f b e nch- to p and system f e atur e s makes this multimeter a versatile solution for y our m easurement n eeds now and in the future.

Convenient Bench-Top Features

• Highly visible vacuum-fluorescent displ a y

• Built-in math operations

• Continuity and diode test functions

• Hands-free, Reading Hold feature

• Portable, ruggedized case with non-skid feet

Flexible System Features

• GPIB (IEEE-488) interface and RS-232 interface

• Standard programming languages: SCPI, Agilent 3478A, and

Fluke 8840

• Reading rates up to 1000 readings per second

• Storage for up to 512 readings

• Limit testing with pass/fail signals

• Optional 34812A BenchLink/Meter Software for Microsoft

Windows

Agilent 34401A Multimeter

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The Front Panel at a Glance

1 Measurement Function keys 2 Math Operation keys 3 Single Trigger / Autotrigger / Reading Hold key 4 Shift / Local key

5 Front / Rear Input Terminal Switch 6 Range / Number of Digits Displayed keys 7 Menu Operation keys

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The Front-Panel Menu at a Glance

The menu is organized in a top-down tree structure with three levels.

A: MEASurement MENU

1: AC FILTER > 2: CONTINUITY > 3: INPUT R > 4: RATIO FUNC > 5: RESOLUTION

B: MATH MENU

1: MIN-MAX > 2: NULL VALUE > 3: dB REL > 4: dBm REF R > 5: LIMIT TEST > 6: HIGH LIMIT > 7: LOW LIMIT

C: TRIGger ME N U

1: READ HOLD > 2: TRIG DELAY > 3: N SAMPLES

D: SYStem MENU

1: RDGS STORE > 2: SAVED RDGS > 3: ERROR > 4: TEST > 5: DISPLAY > 6: BEEP > 7: COMMA > 8: REVISION

E: Input / Output MENU

1: HP-IB ADDR > 2: INTERFACE > 3: BAUD RATE > 4: PARITY > 5: LANGUAGE

F: CALibration MENU

1: SECURED > [ 1: UNSECURED ] > [ 2: CALIBRATE ] > 3: CAL COUNT > 4: MESSAGE

The commands enclosed in square brackets ( [ ] ) are “hidden” unless the multimeter

is UNSECURED for calibration.

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Display Annunciators

∗

Adrs Rmt Man Trig Hold Mem Ratio Math ERROR Rear Shift 4W

Turns on during a measurement. Multimeter is addressed to listen or talk over the GPIB interface. Multimeter is in remote mode (remote interface). Multimeter is using manual ranging (autorange is disabled). Multimeter is waiting for a single trigger or external trigger. Reading Hold is enabled. Turns on when reading memo ry is enabled. Multimeter is in dcv:dcv ratio function. A math operation is enabled (null, min-max, dB, dBm, or limit test). Hardware or remote interface command errors are detected. Rear input terminals are selected. “Shift” key has been pressed. Multimeter is in 4-wire ohms function. Multimeter is in continuity test function. Multimeter is in diode test function.

Press “Shift” again to turn off.

To review the display annunciators, hold down the Shift key as you turn on the multimeter.

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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 Inpu t Fuse

5 Voltmeter Complete Output Terminal 6 External Trigger Input Terminal 7 GPIB (IEEE-488) Interface connector 8 RS-232 interface connector

Use the front-panel Input / Output Menu to:

• Select the GPIB or RS-232 interface (see chapter 4).

• Set the GPIB bus address (see chapter 4).

• Set the RS-232 baud rate and parity (see chapter 4).

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In This Book

Quick Start Chapter 1 prepares the multimeter for use and helps you get familiar with a few of its front-panel features.

Front-Panel Menu Operation Chapter 2 introduces you to the front-panel menu and describes some of t he mu ltimeter’s menu fea tur es.

Features and Functions Chapter 3 gives a detailed description of the multimeter’s capabilities and operation. You will find this chapter useful whether you are operating the multimeter from the front panel or over the remote in t er fac e.

Remote Interface Reference Chapter 4 contains reference information to help you program th e m ultimeter over t he rem ote interface.

Error Messages Chapter 5 lists the error messages that may appear as you are working with the multimeter. Each listing contains enough information to help you diagnose and solve the problem.

Application Programs Chapter 6 contains several remote interface application programs to help you develop programs for your measurement application.

Measurement Tutorial Chapt er 7 discusses measure m e nt considera ti ons an d te chn iq u es to hel p you obt ai n the bes t acc u rac ies and reduce sources of measurement error.

Specifications Chapter 8 lists the multimeter’s specifications and describes how to interpret these specifications.

If you have questions relating to the operation of the Agilent 34401A, call 1-800-452-4844 in the United States, or contact your nearest Agilent Sal es Of fic e .

If your 34401A fails within three years of purchase, Agilent will repair or replace i t free of c harge. Call 1-877-444-7278 (“Agilent Express”) in the United State s, or con tact your n ear est A gile nt Sales Office.

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Contents

Chapter 1 Quick Start

To Prepare th e Multimeter for Us e 13 If the Multi meter Does Not T urn On 14 To Adjust the Carrying Handle 16 To Measure Volt ag e 17 To Measure Resis tan ce 17 To Measur e C urr en t 18 To Measure Frequency (or Period) 18 To Test Continuity 19 To Check Di ode s 19 To Select a Range 20 To Set th e R e s olu t io n 21 Front-Panel Display Formats 22 To Rack Mount th e Multimeter 23

Chapter 2 Front-Panel Menu Operation

Front-Panel Menu Reference 27 A Front-Panel Menu Tutorial 29 To Turn Off the Comma Separator 37 To Make Null (Relative) Measur em en t s 38 To Store Mi nim u m an d Max i mum Reading s 39 To Make dB M eas urements 40 To Make dBm Measurements 41 To Trigger the Multimeter 42 To Use Reading Hold 43 To Make dcv:dcv Ratio Measurements 44 To Use Reading Memory 46

Chapter 3 Features and Functions

Measurement Configuration

AC Signal Filter 51 Continuity Threshold Resistance 52 DC Input Resistance 53 Resolution 54 Integration Time 57 Front / Rear Input Terminal Switching 58 Autozero 59 Ranging 60

Contents

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Contents

Chapter 3 Features and Functions (continued)

Math Operations

Min-Max Operation 64 Null (Relative) Operation 65 dB Measurements 67 dBm Measurements 68 Limit Testing 69

Triggering

Trigger Source Choices 73 The Wait-for-Trigger State 76 Halting a Measurement in Progress 76 Number of S amples 77 Number of Tr ig g er s 78 Trigger Delay 79 Automatic Trigger Delays 81 Reading Hold 82 Voltmeter Complete Terminal 83 External Trigger Terminal 83

System-Related Operations

Reading Memory 84 Error Conditions 85 Self-Test 86 Display Control 87 Beeper Control 88 Comma Separators 89 Firmware Revision Query 89 SCPI Language Version Query 90

Remote Interface Conf iguration

GPIB Address 91 Remo te I n terface Selection 92 Baud Rate Se lection (RS-232) 93 Parity Selection (RS-232) 93 Programming Language Selection 94

Calibration

Calibration Security 95 Calibration Count 98 Calibration Message 99

Operator Maintenance

To Replace the Power-Line Fuse 100 To Replace the Current Input Fu s es 100 Power-On and Reset State 101

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Contents

Chapter 4 Remote I nterface Reference

Command Su mmary 105 Simplified P rog r amming Overview 112 The MEASure? and CONFigure Commands 117 Measurement Configuration Commands 121 Math Operation Commands 124 Triggering 127 Triggering Commands 130 System-Rel ate d Commands 132 The SCPI Status Model 134 Status Reporting Commands 144 Calibration C om ma n ds 146 RS-232 Interface Configuration 148 RS-232 Interface Commands 153 An Introd uct ion to the SCPI L an gu age 154 Output Data Formats 159 Using Device Clear to Halt Measurements 160 TALK ONLY for Printers 160 To Set the GPIB Address 161 To Select the R em ote Interface 162 To Set th e B au d Rate 163 To Set th e P arity 164 To Select the Programming Language 165 Alternate Programming Language Compatibility 166 SCPI Complianc e I nfo rmation 168 IEEE-488 Compliance Information 169

Contents

Chapter 5 Error Messages

Execution Errors 173 Self-Test E r rors 179 Calibration E rr ors 180

Chapter 6 Application Programs

Using MEASure? for a Single Measur ement 185 Using CONFigure with a Math Operation 186 Using the Status Registers 188 RS-232 Operation Using QuickBASIC 192 RS-232 Operation Using Turbo C 193

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Contents

Chapte r 7 Measurement Tutorial

Thermal EMF Errors 199 Loading Errors (dc volts) 199 Leakage Current Errors 199 Rejecting Power-Line Noise Voltages 200 Common Mode Rejection (CMR) 201 Noise Caused by Magnetic Loops 201 Noise Caused by Ground Loops 202 Resistan ce Measurem ents 203 4-Wire Ohms Meas ur em ent s 203 Removing Test Lead Resistance Errors 204 Power Dissipat ion Effects 204 Settling T im e E f fec ts 204 Errors in High Resistance Mea surements 20 5 DC Current Measurement Errors 205 True RMS AC Measurements 206 Crest Fa ct or Errors 207 Loadi ng Errors (a c v olts) 209 Measurem ents Below Full S cal e 210 High-Voltage Self-Heating Errors 210 Temperature Coefficien t and O v erload Errors 210 Low-Level Measurement Errors 211 Common Mode Errors 212 AC Current Measurement Errors 212 Frequency and Peri od M easurement Errors 213 Making H ig h- Speed DC and Res is tance Measurements 213 Making High - Sp eed AC Measurement s 214

Chapter 8 Specifications

DC Character is tic s 216 AC Character is tic s 218 Frequency and Peri od Ch a rac teristics 220 General Information 222 Product Dimensions 223 To Calcula te Tot a l M eas urement Err or 224 Interpreting Multimeter Specifications 226 Configur in g f or H ig h est Accura cy Measurem ents 229

Index 231

Declaration of Conformity 237

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Quick Start

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Quick Start

One of the first things you will want to do with your multimeter is to become acquainted with its front panel. We have written the exercises in this chapter to prepare the multimeter for use and help you get familiar with some of its front-panel operations.

The front panel has two rows of keys to select various functions and operations. Most ke ys have a shifted function printed in bl ue above the key. To perform a shifted function, press annunciator will turn on). Then, press the key that has the desired label above it. For example, to select the dc current function,

Shift DC V .

press

Shift (the Shift

If you accident a l ly press

Shift annunciato r.

The rear cover of this bo ok is a fold -out Qu ick Re feren ce Gu ide. On t his cover you will find a quick summary of va rious multimeter features.

Shift , just press it again to turn off the

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Chapter 1 Quick Start

To Prepare the Multimeter for Use

The following steps help you verify that the multimeter is ready for use.

1 Check the list of suppl ied items.

Verify that you have received the following items with your multimeter. If anyt hi ng i s mi s si ng , c o nt a ct y o ur nearest A g ile n t Sales Offi ce.

One test lead kit. One power cord. This User’s Guide. One Service Guide. One folded Quick Reference card. Certificate of Calibration.

2 Connect the power cord and turn on the multimeter.

The front-panel display will light up while the multimeter performs its power-on self-test. The multimeter powers up in the dc voltage function with autorang ing enab led.

To review the power-on display with all annunciators turned on, hold down

3Perform a complete self-test.

The complete self-test perfor ms a more ex ten siv e ser i es of tests tha n those performed at power-on. Hold down Power switch to turn on the multimeter; hold down the key for more than 5 seconds. The self-test will begin when you release the key.

If the self-test is successful, “ not successful, “ See the Service Guide for instructions on returning the multimeter to Agilent for service.

Shift as you tur n on th e mu lti met e r.

FAIL” is displayed and the ERROR annunciator turns on.

GPIB bus address is displayed. Notice that the

Shift as you pres s the

PASS” is displayed. If the self-test is

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Chapter 1 Quick Start

If the Multimeter Does Not Turn On

Use the following steps to help solve problems you might encounter when turning on the multimeter. If you need more help, see the Service Gui de for instructions on returning the multimeter to Agilent for service.

1 Verify that there is ac power to the multi meter.

First, verify that the multimeter’s Power switch is in the “On” position. Also, make sure that the power cord is firmly plugged into the power module on the rear panel. You should also make sure that the power source you plugged the multimeter into is energized.

2 Verify the power-line voltage setting.

The line voltage i s set to the pr oper valu e for yo ur co un tr y when the multimeter is shipped from the factor y . Chang e t he voltag e se tt ing i f it is not correct. The settings are: 100, 120, 220, or 240 Vac (for 230 Vac operation, use the 220 Vac setting).

See the next page if you need to change the li ne-voltage setting.

3 Verify that the power-line fuse is good.

The multimeter is shipped from the factory with a 250 mA fuse installed. This is the correct fuse for all line voltages.

See the next page if you need to replace the power-line fuse.

To replace the 250 mAT fuse, order Agilent part number 2110-0817.

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Chapter 1 Quick Start

If the Multimeter Does Not Turn On

1 Remov e th e powe r co rd. Remove the

fuse-holder assembly from the rea r pan el.

3 Rotate the line-voltage selector until the

correct voltage appears in the window.

2 Remove the line-voltage selector from

the assembly.

See rear panel for proper fuse rating.

Agilent Part Number: 2110-0817 (250 mAT) 2110-0894 (125 mAT)

4 Replace the fuse-h ol der assemb ly in the rear panel.

100, 120, 220 (230) or 240 Vac

Verify that the correct line voltage is selected and the power-line fuse is good.

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Chapter 1 Quick Start

To Adjust the Carrying Handle

To adjust the position, grasp the handle by the sides and pull outwar d. Then, rotate the handle to the desired position.

Bench-top viewing positions Carrying position

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Chapter 1 Quick Start

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-coupled

To Measure Resistance

Ranges: 100 Ω, 1 kΩ, 10 kΩ, 100 kΩ, 1 MΩ, 10 MΩ, 100 MΩ Maximum resolution: 100 µΩ (on 100 ohm range)

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Chapter 1 Quick Start

To Measure Current

Ranges: 10 mA (dc only), 100 mA (dc only), 1 A , 3 A Maximum resolution: 10 nA (on 10 mA range) AC technique: true

RMS, ac-coupled

To Measure Frequency (or Period)

Measurement band: 3 Hz to 300 kHz (0.33 sec to 3.3 µsec) Input signal range: 100 mVac to 750 Vac Techniqu e: reciprocal count i ng

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Chapter 1 Quick Start

To Test Continuity

Test current source: 1 mA Maximum resolution: 0.1 Beeper threshold: 1

Ω (range i s fi xed at 1 ko hm )

Ω to 1000 Ω (beeps below adjustable threshold)

To Check Diodes

Test current source: 1 mA Maximum resolution: 100 Beeper threshold: 0.3 volts

µV (range i s fi xed at 1 Vd c)

≤ V

measured

≤ 0.8 volts (no t adjustable)

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Chapter 1 Quick Start

To Select a Range

You can let the multimeter automatically select the range using autoranging or you can select a fi xed range using manual ra nging.

Selects a lower range and disables autoranging.

Selects a higher range and disables autoranging.

Toggles betwee n aut or anging and manual ranging.

• Autoranging is sel e ct ed a t p ower-on a nd a ft e r a re m ot e i nt erf a ce reset.

• Autorange t h re sholds:

Man annu nci ator is on when manual range is enabl ed.

Down range at <10% of range Up range at >120% of range

• If the input signal is greater than the present range can measure,

the multimeter will give an overload indication (“

• For frequency and period measurements from the front panel,

OVLD”).

ranging applies to the signal’s input voltage, not its frequency.

• The range is fixed for conti n u ity (1 kΩ range) and diode (1 Vdc ran g e).

Ranging is local to the selected function. This means that you can select the ranging method (auto or manual) for each function independently. When manually ranging, the selected range is local t o th e fu nction ; the multimeter remembers the range when you switch between functions.

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Chapter 1 Quick Start

To Set the Resolution

You can set the display resolution to 4

⁄

, 5

⁄

, or 6

⁄

digits either to

optimize measur emen t speed or nois e reje ction. In this book, the most

⁄

significant digit (leftmost on the display) is referred to as the “

” digit,

since it can only be a “0” or “1.”

Press the Shift key.

Selects 4

⁄2 digits.

Selects 5

⁄2 digits.

Sele cts 61⁄2 digits (most noise reject i on ).

• The resolution is set to 5

⁄

digits at power-on and after a remote

interface reset.

• The resolution is fixed at 5

• You can also vary the number of digits displayed using the arrow keys

⁄

digits for continuity and diode tests.

(however, the integration time is not changed).

Fewer More Digits Digits

Resolutio n is local to t he selected func tion. This means t hat you can select the r esolutio n for each fun ction inde pendently. T he multime ter remembers the resolution when you switch between functions.

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5 digits

Chapter 1 Quick Start

Front-Panel Display Formats

Front-Pan el Display Formats

– Negative sign or blank (positive)

H “

-H.DDD,DDD EFFF

Front-pa ne l display forma t.

10.216,5 VDC

D Numeric digits E Exponent ( m, k, M ) F Measurement units ( VDC, OHM, HZ, dB )

⁄2 ” digit (0 or 1)

“1⁄2” digit

This is the 10 Vdc range, 5

⁄

digits are displayed.

-045.23 mVDC

This is the 100 mVdc range, 4

⁄

digits are displayed.

113.325,6 OHM

This is the 100 ohm range, 6

⁄

digits are displayed.

OVL.D mVDC

This is an overload indication on the 100 mVdc range.

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Chapter 1 Quick Start

To Rack Mount the Multimeter

You can mount the multi m eter in a standard 19 -inch rack cabinet using one of three optional kits available. In struc tions and m ountin g hardw are are included with each r ack-mou nting kit . Any instrument of the same size can be rack-mounted beside the 34401A.

Remove the carrying handle, and the front and rear rubber bumpers, before rack- m ounting the multim eter.

Agilent System II

To remove the handle, rotate it to the vertical position and pull the ends outward.

Fron t

To remove the rubber bumper, stretch a corner and then slide it off.

Rear (bottom view)

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Chapter 1 Quick Start

To Rack Mount the Multimeter

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 flange kit 5063-9212.

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 order filler panel 5002-3999).

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Front-Panel Menu Operation

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Front-Panel Menu Operation

By now you should be familiar with the FUNCTION and RANGE / DIGITS groups of fro nt -panel keys. You should also understand how to make front-panel connections for the various types of measurements. If you are not familiar with this information, we recommend that you read chapter 1, “Quick Start,” starting on page 11.

This chapter introduces you to three new groups of front-panel keys:

MENU, MATH, and TRIG. You will also learn how to use the comma

separator and store readings in memory. This chapter does not give a detailed description of every front-panel ke y or menu operation. It does, however, give you a good ov er vie w of th e fro nt- pan el menu a nd many front-panel operations. See chap t er 3 “ F eat u re s and Fun c tion s ,” starting on page 49, for a complete discussion of the multimeter’s capabilities and operation.

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Chapter 2 Front-Panel Menu Operation

Front-Panel Menu Reference

A: MEASurement MENU

1: AC FILTER > 2: CONTINUITY > 3: INPUT R > 4: RATIO FUNC > 5: RESOLUTION

1: AC FILTER 2: CONTINUITY 3: INPUT R 4: RATIO FUNC 5: RESOLUTION

Selects the slow, medium, or fast ac filter. Sets the continuity beeper threshold (1 Ω to 1000 Ω). Sets the input r esistance for dc voltage measurements.

Enables the dcv:dcv ratio function. Selects the measuremen t resolution.

B: MATH MENU

1: MIN-MAX > 2: NULL VALUE > 3: dB REL > 4: dBm RE F R > 5: LIMIT TES T > 6: HIGH LIMI T > 7: LOW LIMIT

1: MIN- MAX 2: NULL VALUE 3: dB REL 4: dBm REF R 5: LIMIT TEST 6: HIGH LIMIT 7: LOW LIMIT

Recalls the stored minimum, maximum, average, and reading count. Recalls or sets the null value stored in the null re gister. Recalls or sets the dBm value stor ed in the d B relati ve register. Selects the dBm reference resistance value. Enables or disables limit testing. Sets the upper limit for limit testing. Sets the low er limit for limit testing.

C: TRIGger MENU

1: READ HOLD > 2: TRIG DELAY > 3: N SAMPLES

1: READ HOLD 2: TRIG DELAY 3: N SAMPLES

Sets the readin g ho ld se ns itiv ity ban d. Specifies a time inte rval which is inserted before a mea s uremen t. Sets the nu mb er of sa mp le s p er tr ig ge r .

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Chapter 2 Front-Panel Menu Operation

Front-Panel Menu Reference

D: SYStem MENU

1: RDGS STORE > 2: SAVED RDGS > 3: ERROR > 4: TEST > 5: DISPLAY > 6: BEEP > 7: COMMA > 8: REVISION

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 sto red in memory (up to 512 readings). Retrieves errors from the error queue (up to 20 errors). Performs a complete self-test. Enables or disables th e front-panel display. Enables or disables the beeper function. Enables or disables a co mma separator between digi ts on the display. Displays the multimeter’s fir mware revision codes.

E: Input / Output MENU

1: HP-IB ADDR > 2: INTERFACE > 3: BAUD RATE > 4: PARITY > 5: LANGUAGE

1: HP-IB ADDR 2: INTERFACE 3: BAUD RATE 4: PARITY 5: LANGUAGE

F: CALibra tion MENU

1: SECURED > [ 1: UNSECURED ] > [ 2: CALIBRATE ] > 3: CAL COUNT > 4: MESSAGE

1: SECURED 1: UNSECURED 2: CALIBRATE 3: CAL COUNT 4: MESSAGE

Sets the GPIB bus address (0 to 31). Selects the GPIB or RS-232 interface. Selects the baud rate for RS-232 operation. Selects even, odd, or no parity for RS-232 operation. Selects the interface language: SCPI, Agilent 3478, or Fluke 8840/ 42.

The multimeter is secur ed against calibration; enter c ode to unse cure. The multimeter is unsecured for calibration; enter code to secure. Performs complete calibration of present function; must be UNSECURED. Reads the total number of times the multimeter has been calibrated. Reads the calibration string (up to 12 characters) entered from remote.

The commands enclosed in square brackets ( [ ] ) are “hidden” unless the multimeter is UNSECURED for calibration.

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Chapter 2 Front-Panel Menu Operation

A Front-Panel Menu Tutorial

A Front-Pan el Menu Tutorial

This section is a step-by-step tutorial which shows how to use the front-panel menu. We recommend that you spend a few minutes with this tutorial to get comfortable with the structure and operation of the menu.

The menu is organized in a top-down tree structure with three levels (menus, commands, and parameters). You move down

or up

∧ the menu tree to get from one level to the next. Each of the

three levels has several horizontal choices which you can v i ew by moving left

< or right > .

Menus

Commands

∨

Parameters

• To turn on the menu, press Shift Menu On/Off .

• To turn off the men u , pres s Shift Menu On/Off , or press any of

the function or math keys on the top row of front-panel keys.

• To execute a menu command, press Enter .

• To recall the last menu command that was executed,

Shift Recall .

press

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Chapter 2 Front-Panel Menu Operation

A Front-Panel Menu Tutorial

MESSAGES DISPLAYED DURING MENU USE

TOP OF MENU You pressed while on the “menus” level; this is the top level of

the menu and you cannot go any higher. To turn off the menu, press (Menu On/Off). To move across the choices

on a level, press or . To move down a level, press .

MENUS You are on the “menus” level. Press or to view the choices. COMMANDS You are on the “commands” level. Press or to view the

command c hoices within the selected menu group.

PARA METER You are on the “parameter” level. Press or to view and edit

the parameter for the selected comm and.

MENU BOTTOM You pressed while on the “parameter” level; this is the bottom

level of the menu and you cannot go any l ower. To turn off the menu, press (Menu On/Off). To move up a level,

press .

∧

CHANGE SAVED The change made on the “parameter” level is saved. This is

displayed after you press (Menu Enter) to execute the command.

MIN VALUE The value you s pecifie d on the “parameter” level is too small for the

selected command. The minimum value allowed is displayed for you to edit.

MAX VALUE The value you specified on the “parameter” level is too large for the

selected command. The maximu m value allowed is displayed for you to edit.

EXITING MENU You will see this message if you turn off the menu by pressing

(Menu On/Off) or a front-panel function/math key. You did not edit any values

Shift

on the “para meter” level and changes were NO T saved.

< >

∧

Shift <

∨

Shift

Auto/Man

∨

NOT ENTERED You will see this message if you turn off the menu by pressing

(Menu On/Off) or a front-panel function/math key. You did some editing of

Shift parameters but the changes were NOT saved. Press (Menu Enter) to save changes made on the “parameter” level.

NOT RELEVANT The selected math operation is NOT valid for the function in use.

Auto/Man

Page 33

Chapter 2 Front-Panel Menu Operation

A Front-Panel Menu Tutorial

Menu Example 1 The following steps show yo u h ow to turn on the men u, mo ve up or

down between levels, move across the choices on each level, and turn off the menu. In this example, you will turn off the front-panel beeper.

On/Off

Shift <

> >

∨

1 Turn on the menu.

You enter the menu on the “menus” level. The

MEAS MENU is your first

choice on this level.

A: MEAS MENU

2 Move across to the SYS MENU choice on this level.

There are six menu grou p choi c es a vaila ble on the “men u s” level. Each choice has a letter prefix for eas y ident ifica tion (

A: , B: , etc.).

D: SYS MENU

3 Move down to the “commands” level within the SYS MENU.

RDGS STORE command is your first choice on this level.

The

1: RDGS STORE

Page 34

Chapter 2 Front-Panel Menu Operation

A Front-Panel Menu Tutorial

> > > > >

∨

4 Move across to the BEEP command on the “commands” level.

There are eight command choices available in the choice on this level has a n umber prefi x for ea sy identifi cation (

SYS MENU. Each

1: , 2: , etc.).

6: BEEP

5 Move down a level to the BEEP parameter choices.

The first parameter choice is “ setting is stored in non-volatile memory and “

ON” for the BEEP command (the beeper

ON” is the factory setting).

6 Move across to the “OFF” choice.

There are two parameter choices for

BEEP.

OFF

Auto/Man

ENTER

7 Save the change and turn off the menu.

The multimeter beeps and displays a message to show that the change is now in effect. You are then exited from the menu.

CHANGE SAVED

Page 35

Chapter 2 Front-Panel Menu Operation

A Front-Panel Menu Tutorial

Menu Example 2 The following exercise dem onstrates how to use the menu recall feature

as a shortcut to set the

BEEP command back to its original setting.

You must perform the steps in Exam ple 1 before you start this example.

Shift

∨

Recall

1 Use menu recall to return to the

This returns you to the

BEEP command, which was the last command

BEEP command.

used before you exi ted t he me nu i n the Exa mple 1.

6: BEEP

2 Move down to the BEEP parameter choices.

The first parameter choice is “

OFF” (the current sett i ng from Example 1).

OFF

3 Move across to the “ON” choice.

Set the parameter back to its original value.

Auto/Man

ENTER

4 Save the change and turn off the menu.

The multimeter beeps and displays a message to show that the change is now in effect. You are then exited from the menu.

CHANGE SAVED

Page 36

Chapter 2 Front-Panel Menu Operation

A Front-Panel Menu Tutorial

Menu Example 3 Some commands in the menu require that you enter a numeric

parameter value. The following steps show you how to enter a number in the menu. For this example, you will set the null value to –2.0 volts.

Make sure the mul timeter is in the dc vo ltage function with 5

resolution displayed. Disconnect all inputs to the multimeter.

On/Off

Shift <

1 Turn on the menu.

⁄

digits of

∨

You enter the menu on the “menus” level. The

MEAS MENU is your first

choice on this level.

A: MEAS MENU

2 Move across to the MATH MEN U choice on this level.

There are six menu grou p choi c es a vaila ble on this level.

B: MATH MENU

3 Move down to the “commands” level within the MATH MENU.

The

MIN–MAX command is your first choice on this level.

1: MIN-MAX

4 Move across to the NULL VALUE command on this level.

There are seven command choices available within the

2: NULL VALUE

MATH ME NU.

Page 37

Chapter 2 Front-Panel Menu Operation

A Front-Panel Menu Tutorial

∨

∨ ∨

5 Move down to edit the NULL VALUE parameter.

The null value should be 0.0 Vdc when you come to this point in the menu for the first time. For this example, you will set the null value to –2.0 volts.

∧000.000 mVDC

When you see the flashing “∧” on the left side of the display, you can abort the edit and return to the “commands” level by pressing

6 Make the number negative.

The leftmost character on the display toggles between + and – .

-000.000 mVDC

7 Move the flashing cursor over to edit the first digit.

Notice that the leftmost digit is flashing.

∧ .

∧

-000.000 mVDC

8 Increment the first digit until “ 2 ” is displayed.

You decrement or increment each digit independently. Neighboring digits are not affected.

-200.000 mVDC

Page 38

Chapter 2 Front-Panel Menu Operation

A Front-Panel Menu Tutorial

< <

∧

Auto/Man

ENTER

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 mVDC

10 Increase the displayed number by a factor of 10.

Notice that the position of the decimal point changes and the displayed number increases by a factor of 10.

-2.000,00 VDC

11 Save the change and turn off the menu.

The multimeter beeps and displays a message to show that the change is now in effect. You are then exited from the menu.

CHANGE SAVED

Keep in mind that math null is turned on and –2.0 volts i s u sed a s the null va lu e for m ea su r e men ts. To clear the nu ll value, pres s

Null .

This is the end of the front-panel menu tutorial. The remainder of the

chapter discusses several of the most common front-panel operations.

Page 39

Chapter 2 Front-Panel Menu Operation

To Turn Off the Comma Separator

The multimet er can display re adi n gs on the fr on t panel w it h or with ou t a comma separator. The following steps show how to disable the comma.

On/Off

Shift <

∨

08.241,53 VDC

With comma separator

(factory setting) Without comma separator

08.24153 VDC

1 Turn on the menu.

A: MEAS MENU

2 Move across to the SYS MENU choice on the “menus” level.

D: SYS MENU

3 Move down a level and then across to the COMMA command.

7: COMMA

4 Move down a level and then move across to the “OFF” choice.

Auto/Man

ENTER

OFF

5 Save the change and turn off the menu.

The comma separator setting is stored in non-volatile memory, and does not ch ange when pow er has been off or a fter a r em ote interface reset.

Page 40

Chapter 2 Front-Panel Menu Operation

To Make Null (Relative) Measurements

Each null measurement, also called relative, is the difference between a stored null value a nd the i n put signal.

Result = reading – null value

To read / edit the null value, use the MATH menu.

Enables null ope rati on; Press again to di sable.

• You can make null m easurements wi t h any function except

Math annunciator is on when null operation is enabl ed.

continuity, diode, or ratio. The null operation is local to the selected function ; when yo u chan g e fu nct ion s , null is disab led.

• To null the test lead resistance for more accurate two-wire ohms

measurements, short the ends of the test leads together and then

Null .

press

• The first reading taken after you press Null is stored as the null

value in the Null Register. Any previously stored value is replaced with the new value.

• After enabling null, you can edit the stored null value by

pressing

NULL VAL UE ” command in the MATH MENU (only if null is

“

Shift > (Menu Recall). This takes you to the

enabled). Go down to the “parameter” level, and then edit the displayed value.

• The null register is c lear ed wh en yo u chan g e fu nct ion s, tu rn nul l off,

turn off the power, or perform a remote interface reset.

Page 41

Chapter 2 Front-Panel Menu Operation

To Store Minimum and Maximum Readings

You can store the minimum and maximum readings during a series of measuremen t s. The follow i ng dis cus s ion show s how to rea d the minimum, maximum, average, and reading count.

To read the minimum, ma ximu m, average, and count, use the MATH menu.

Enables min-max operation; Press again to dis able.

• You can use min-max with any fu nction ex cept c ontinuity or diode test.

Math annunciator is on when min-max operation is enabled.

The min-max operation is local to the selected function; when you change functions, min-max is disabled.

•• After enabling min-max, you can read the stored minimum,

maximum, average, and count by pressing

This takes you to the “

MIN–MAX” command in the MATH MENU

Shift > (Menu Recall).

(only if min-max is ena bled). Go down to the “parameter” level, and then read the values by pressing

• The stored valu es are c l ear ed when yo u tu rn min- m ax off , turn off t he

< or > .

power, or perform a remote interface reset.

• The average is of all re a din gs t aken sin c e min- m ax w as ena bl ed (n ot

just the average of the stored minimum and maximum). The count is the total number of readings taken since min-max was enabled.

Page 42

Chapter 2 Front-Panel Menu Operation

To Make dB Measurements

Each dB measurement is the difference between the input signal and a stored relative value, with both values converted to dBm.

dB = reading in dBm – relative value in dBm

To read / edit the dB relativ e value, use the MATH menu .

Enables dB operat ion; Press again to disa bl e.

• Select DC V or AC V .

• The first reading taken after you enable dB measurements is

Math annunciator is on when dB operation is enabl ed.

converted to dBm and is stored as the relative value in the dB Relative Register. Any previously stored value is replaced with the new value.

• After enabling dB operations, you can edit the relative value by

pressing

command in the

Shift > (Menu Recall). This takes you to the “dB REL”

MATH MENU (only if dB is enabled) . Go down to

the “p a rame t er ” level, and then edit th e valu e dis pla yed.

• The register is cl ear ed when yo u c hang e fu nc tion s , tu rn dB off,

turn off the power, or perform a remote interface reset.

Page 43

Chapter 2 Front-Panel Menu Operation

To Make dBm Measurements

The dBm operation calculates the power delivered to a resistance referenced to 1 milliwatt.

dBm = 10

× Log

( reading

/ reference resistance / 1 mW )

To read / edit the dBm refer enc e res is tance, use the MATH menu.

Enables dBm oper at ion; Press again to dis able.

• Select DC V or AC V .

• The factory setting for the reference resistance is 600 Ω. To select a

different value, press

operations. This takes you to the “

MATH MENU (only if dBm is enabled).

Shift > (Menu Recall) after enabling dBm

dBm REF R” command in the

Math annunciator is on when dBm operation is enabled.

Go down to the “ p ar am eter” lev el, an d then selec t a value: 50, 75, 93, 110, 124, 125, 135, 150, 250, 300, 500, 600, 800, 900, 1000, 1200, or 8000 ohms.

• The reference resistance is stored in non-volatile memory, and does no t

change when power has been off or after a remote interface reset.

Page 44

Chapter 2 Front-Panel Menu Operation

To Trigger the Multimeter

You can trigger the multimeter from the front panel using single trigger or auto trigger.

Enables single trigger and triggers the multimeter.

Toggles betwe en aut o trigger and reading hold.

• Auto trigger ing is ena bled w he n y ou tur n on the mu l ti met er. Not ic e

that the

• Single triggering takes one reading each time you press Single

∗ (sample) annunciator turns on during each measurement.

and then waits for the next trigger. Continue pressing this key to trigger the multimeter.

Using an External Trigger

The external trigger mode is also enabled by pressi ng . It is like the single trigger mode except that you apply a tri gger pulse t o t he re ar-panel Ext Trig terminal. The mult imet er is trigger ed on t he negative edge of a TTL pulse.

The front-panel key is disabled when in remote.

Single

(sample) annunciator is on

∗

during each measur ement .

Trig annunciator is on when the multimeter is waiting f or singl e trigger (auto trigge r disabled).

Single

Page 45

Chapter 2 Front-Panel Menu Operation

To Use Reading Hold

The reading hold feature allows you to capture and hold a stable reading on the display. When a stable reading is detected, the multimeter emits a beep and holds the value on the display.

To adjust the rea di ng hold sensitivity band, use the TRIG men u.

Toggles between aut o trigger and reading hold.

• Reading hold has an adjustable sen s iti vit y b an d to allow you to

Hold annunciator is on when reading hold is enabled.

select which readings are considered stable enough to be displayed. The band is expres sed as a perc en t of re ad in g on the s elec ted r ang e. The multimeter will capture and display a new value only after three consecutiv e r ea din g s are wit h in the b and .

• The default band is 0.10% of reading. After enabling reading hold,

you can choose a different band by pressing

Shift >

(Menu Recall). This takes you to the “READ HOLD” c ommand in

TRIG MENU (only if read ing hol d is enable d ).

the Go down to the “ p ar am eter” lev el, an d then selec t a value:

0.01%, 0.10%, 1.00%, or 10.00% of reading.

• The sensitivity band is stored in volatile memory; the multimeter

sets the band to 0.10% of reading when power has been off or after a remote interface reset.

Page 46

Chapter 2 Front-Panel Menu Operation

To Make dcv:dcv Ratio Measurements

To calculate a ratio, the multimeter measures a dc reference voltage applied to the terminals.

To enable ratio me asurem ent s, use the MEAS menu.

Sens e terminals and the voltage applied to the Input

Ratio =

dc signal voltage

dc reference voltage

Ratio annunciator is on when

• At the Sense terminals, the reference voltage measurement function

ratio measurem ents ar e enabled.

is always dc voltage and has a maximum measurable input of

±12 Vdc. Autoranging is automatically selected for reference voltage

measurements on the

• The Input LO and Sense LO terminals must have a common reference

and cannot hav e a volta ge di ff er en ce great er than

• The specified measurement range applies only to the signal connected

Input terminals. The signal on the Input ter minals can be any

to the

Sens e terminals.

±2 volts.

dc voltage up to 1000 volts.

Page 47

On/Off

Shift <

∨

Chapter 2 Front-Panel Menu Operation

To Make dcv:dcv Ratio Measurements

The following steps show yo u h ow to selec t the ratio function using the front-panel menu.

1 Turn on the menu.

A: MEAS MENU

2 Move down a level and then across to the RATIO FUNC command.

4: RATIO FUNC

∨

Auto/Man

ENTER

3 Move down to the “parameter” level.

For this command, there is only one choice on this level.

DCV:DCV

4 Select the ratio function and turn off the menu.

Notice that the

Ratio annunciator turns on.

CHANGE SAVED

To disabl e rat io measurement s, select a different measurement function by pressing any front-panel function key.

Page 48

Chapter 2 Front-Panel Menu Operation

To Use Reading Memory

The multimeter can store up to 512 readings in internal memory. The following steps demonstrate how to store readings and retrieve them.

1 Select the func tio n.

Select any measurement functi on. You can also sele ct Nu ll, Min–Max, dB, dBm, or limit test. You can change the function at any time during reading memory.

Single

On/Off

Shift <

> > >

∨

2 Select the single trigger mode.

Notice that the

Tri g annunc iator turns on. When reading memory is

enabled, read i ngs are s tor ed wh en yo u tr igger the mul tim eter .

For this example, single triggering is used to store readings. You can also use auto triggering or reading hold.

3 Turn on the menu.

A: MEAS MENU

4 Move across to the SYS MENU choice on this level.

D: SYS MENU

5 Move down to a level to the RDGS STORE command.

1: RDGS STORE

Page 49

Chapter 2 Front-Panel Menu Operation

To Use Reading Memory

Auto/Man

ENTER

Single Single Single

Recall

Shift >

> ∨

6 Move down a level and then across to the “ON” choice.

7 Save the change and exit the menu.

Notice that the multimeter is ready to store readings. Up to 512 readings can be stored in fir st-i n-f irs t-ou t ( will turn off.

Readings are preserved until you re-enable reading memory at another time, tur n of f the power, or perform a remote interface reset.

8 Trigger the multimeter three times.

This stores three readings in memory.

9 Use menu recall to retrieve the stored readings.

This takes you to the “

Mem (memory) annun ci a t or turns on to indicat e that the

FIFO) order. When memory is full, the Mem annunciator

SAVED RDGS” command in the SYS ME NU.

2: SAVED RDGS

Page 50

Chapter 2 Front-Panel Menu Operation

To Use Reading Memory

∨

On/Off

Shift <

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 first readi ng displayed is the first reading that was stored (FIFO). If no readings are s tor ed in mem or y, “

readings are displayed with their units (

EMPTY” is displayed. The stored

µ, m, k, etc.) when appropriate.

For example:

Reading number

10.31607K: 1

Exponent

11 Move across to view the two remaining stored readings.

The readings a re stor ed horizontally on the “paramet er ” level. If you press

< when you get to the “parameter” level, you will see the

last reading and you will know how many readings were stored.

12 Turn off the menu.

EXITING MENU

Page 51

Features and Functions

Page 52

Features and Functions

You will find that this chapter makes it easy to look up all the details about a particular feature of the multimeter. Whether you are operating the multimeter from the front panel or from the remote interface, this chapter will be useful. This chapter is divided into the following sections:

• Measurement Configuration, starting on page 51

• Math Operations, starting on page 63

• Triggering, starting on page 71

• System-Rela ted O per a tion s , star ti ng on page 84

• Remote Interface Configuration, starting on page 91

• Calibration Overview, starting on page 95

• Operator Maintenance, starting on page 1 00

• Power-On and Reset State, o n page 101

Some knowledge of the front-panel menu will be helpful before you read this chapter. If you have not already read chapter 2, “Front-Panel Menu Operation,” starting on page 25, you may want to read it now. Chapter 4 , “Remote Interface Reference,” starting on page 103, lists the syntax for

SCPI commands available to program the multimeter.

the 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 parameters within a command string.

• Triangle brackets ( < > ) indicate that you must substitute a value

for the enclosed parameter.

• A vertical bar (

) separates multiple parameter choices.

Page 53

Chapter 3 Features and Functions

Measurement Configuration

This secti on contains information to hel p you configure the multimeter for making measurements. You may never have to change any of the measurement parameters discussed here, but they are provided to give you the flexibility you might need.

AC Signal Filter

The multimet er uses thr ee diffe re nt a c filte rs whi c h enable y ou to eith er optimize low frequency accuracy or achieve faster ac settling times. The multimeter selects the slow, medium, or fast filter based on the input freque ncy t ha t you specify.

Applies to ac vo ltage and ac current m easurements only.

Input Frequency

3 Hz to 300 kHz 20 Hz to 300 kHz 200 Hz to 300 kHz

• The ac filter selection is stored in volatile memory; the multimeter

AC Filter Selected

Slow f ilter Mediu m filt er (d ef au lt ) Fast filter

Settling Time

7 seconds / reading 1 reading / second 10 readings / second

selects the medium filter (20 Hz) when pow er has been off or aft er a remote interface reset.

• Front-Panel Operation: Select from the menu the slow filt er (3 Hz),

medium filter (20 Hz), or fast filter (200 Hz). The default is the

medium filter.

1: AC FILTER (MEAS MENU)

• Remote Interface Operation: Specify the lowest frequ en cy ex pec ted in

the input signal. The multimeter selects the appropriate filter based on the frequency you specify (see table above). The

CONFigure and

MEASure? commands select the 20 Hz filter.

DETector:BANDwidth {3|20|200|MINimum|MAXimum}

Page 54

Chapter 3 Features and Functions

Measurement Configuration

Continuity Threshold R esistance

When measuring continuity, the multimeter emits a continuous tone if the measured resistance is less than the threshold resistance. You can

set the threshold to any value between 1

The threshold resistance is adjustable only from the front panel .

• The threshold resistance is stored in non-v olatile mem or y, an d does not

change when power has been off or after a remote interface reset.

• The factory setting for the threshold resistance is 10 Ω.

• After enabling the continuity function, you can select a different

threshold resistance by pressi ng

Ω and 1000 Ω.

Shift > (Menu Recall).

2: CONTINUITY (MEAS MENU)

See also “To Test Conti nuity,” on page 19.

∧0010 OHM

Page 55

Chapter 3 Features and Functions

Measurement Configuration

DC Input Resistance

Normally, the multimeter’s input resistance is fixed at 10 MΩ for all dc voltage ranges to mini mize n oi se pi cku p. To r edu c e the eff ec ts of measurement loading errors, you can set the input resistance to greater than 10 G

Applies to dc voltage meas ureme nts an d is d isab led for all oth er fu nctions .

Fixed Resistance ON (default) Fixed Resistance OFF

• The input resi stan c e set ting is stor ed in volatile memory; the

multimeter selects 1 0 M has been off or after a remote interface reset.

Ω for the 100 mVdc, 1 Vdc, and 10 Vdc ranges.

Input Resistance Input Resistance 100mV, 1V, 10V ranges 100V, 1000V ranges

10 MΩ 10 MΩ > 10 GΩ 10 MΩ

Ω (for all dc voltage ranges) wh en pow er

• Front-Panel Operation: Select from the menu the 10 MΩ mode (fixed

resistance fo r all d c volt a ge ranges) or the >10 G

is 10 M

• Remote Interface Operation: You can enable or disable the automatic

input resistance mode. With is fixed at 10 M is set to >10 G

Ω.

3: INPUT R (MEAS MENU)

AUTO OFF (default), the input resistance

Ω for all ranges. With AUTO ON, the input resistance

Ω for the three lowest dc voltage ranges. Th e CONFigure

Ω mode. The default

and MEASure? commands automatically turn AUTO OFF.

INPut:IMPedance:AUTO {OFF|ON}

Page 56

Chapter 3 Features and Functions

Measurement Configuration

Resolution

Resolution is expr es sed in t erm s of number of digits the multimeter can measure or display. You can set the resolution to 4, 5, or 6 full digits, plus a “ accuracy and improve noise rejection, select 6 measurement speed, select 4

Applies to all measurement functions. The resolution for the math operations (null, min-max, dB, dBm, limit test) is the same as the resolution for the measu rem ent function i n use.

The correspondence between the number of digits selected and the resulting integration time (in power line cycles) is shown below. The autozero mode is set indirectly when you set the resolution.

See also “Autozero,” on page 59.

⁄

” digit which can only be a “0” or “1”. To increase measurement

⁄

digits.

⁄

digits. To increase

Resolution Choices

Fast 4 Digit

* Slow 4 Digit

Fast 5 Digit

* Slow 5 Digit (default)

* Fast 6 Digit

Slow 6 Digit

* These settings configure the multimeter just as if you had pressed the corresponding “DIGITS” keys from the front panel.

Integration Time

0.02 PLC 1 P LC

0.2 PLC 10 PLC

10 PLC 100 PLC

Resolutio n is local to t he selected func tion. This means t hat you can

select the r esolutio n for each fun ction inde pendently. T he multime ter

remembers the resolution when you switch between functions.

Page 57

5 digits

Chapter 3 Features and Functions

Measurement Configuration

10.216,5 VDC

“1⁄2” digit

⁄

This is the 10 Vdc range, 5

digits are displayed.

-045.23 mVDC

This is the 100 mVdc range, 4

⁄

digits are displayed.

113.325,6 OHM

This is the 100 ohm range, 6

⁄

digits are displayed.

• The resolutio n is stor ed in volatile memory; the multimeter sets the

resolution to 5

⁄

digits (for all functio ns ) w hen pow er has b een off or

after a remote interface reset.

• The resolution is fixed at 5

• For dc and resistance measurements, changing the number of digits

⁄

digits for continuity and diode tests.

does more than just change the resolution of the multimeter. It also changes the integration time, which is the period the multimeter’s analog-to-digital (A/D) converter samples the input signal for a measurement. See also “Integration Time,” on page 57.

• For ac measurements, the resolution is actually fixed at 6

If you select 4

⁄

digits or 5

⁄

digits, the multimeter “masks” one or

⁄

digits.

two digits. The only way to c ontrol th e reading rate for ac measur ements is by setting a trigger delay (see page 79).

• For ratio measurements, the specified resolution applies to the signal

connected to the

Input terminals.

Page 58

Chapter 3 Features and Functions

Measurement Configuration

Resolution

(continued)

• Front-Panel Operation: Select either the slow or fast mode for eac h

resolution setting. The default m ode is 5 digits slow.

5: RESOLUTION (MEAS MENU)

See also “To Set the Resolution,” on page 21.

• Remote Interface Operation: You can set the resolution using the

foll owing co m m a nds.

CONFigure:<function> {<range>|MIN|MAX|DEF},{<resolution>|MIN|MAX|DEF}

MEASure:<

function>:RESolution {<resolution>|MIN|MAX}

function>? {<range>|MIN|MAX|DEF},{<resolution>|MIN|MAX|DEF}

Specify the resolution in the same units as the measurement function, not in nu m b er of digi ts. For example, for dc volts , specify the resolution in volts. For frequency, specify the resolution in hertz.

CONF:VOLT:DC 10,0.001 4 MEAS:CURR:AC? 1,1E-6 6

⁄

digits on the 10 Vdc range

⁄

digits o n th e 1 A ra n g e

CONF:FREQ 1 KHZ,0.1 Hz 1000 Hz input, 0.1 Hz resolution VOLT:AC:RES 0.05 50 mV resolution on the ac fun ction

Page 59

Chapter 3 Features and Functions

Measurement Configuration

Integration Time

Integration time is the period during which the multimeter’s analog-todigital (A/D) converter samples the input signal for a measurement. Integration time affects the measurement resolution (for better resolution, use a longer integration time), and measurement speed (for faster measurements, use a shorter integration time).

Applies to all measurement functions except ac voltage, ac current, frequency, and period. The integration time for the math operations (null, min-max, dB, dBm, limit test) is the same as the integration time for the measurement function in use.

• Integration time is specified in number of power line cycles (NPLCs).

The choices are 0.02, 0.2, 1, 10, or 100 power line cycles. The default is 10 PLCs.

• The integration time is stored in volatile memory; the multimeter

selects 10 PLCs when power has been off or after a remote interface reset.

• Only the integral number of power line cycles (1, 10, or 100 PLCs)

provide normal mode (line frequency noise) rejection.

• The only way to contr ol th e reading rate for ac measu r em en ts is by

setting a trigger delay (see page 79).

• The following table shows the relationship between integration time

and measurement resolution.

Integration Time

0.02 NPLC

0.2 NPLC 1 NPLC 10 NPLC 100 NPLC

Resolution

0.0001 x Full-Scale

0.0000 1 x Full-Scale

0.000003 x Full-Scale

0.000001 x Full-Scale

0.0000 00 3 x F ull -S ca le

Page 60

Chapter 3 Features and Functions

Measurement Configuration

Integration Time

(continued)

• Front-Panel Operation: Integration time is set indirectly when you

select the numbe r o f d i gi t s. See the table for resolution on page 54.

• Remote Interface Operation:

<function>:NPLCycles {0.02|0.2|1|10|100|MINimum|MAXimum}

For frequen cy an d per iod m eas urem e nts , aperture time (or gate time)

⁄

is analogous to integration time. Specify 10 ms (4 (default; 5

⁄

digits), or 1 second (6

⁄

digits).

digits), 100 ms

FREQuency:APERture {0.01|0.1|1|MINimum|MAXimum} PERiod:APERture {0.01|0.1|1|MINimum|MAXimum}

Front / Rear Input Terminal Switching

Any measurement made using the front terminals can also be made using the input terminals on the rear panel. See “The Front Panel at a Glance,” on page 2, for the locati on of the front / rear switch.

The input terminals can only b e configured fro m the front panel. You cannot select the terminals from the remote interface, but you can query the present setting.

• The Rear annunciator turns on when you select the rear terminals.

• Remote Interface Operation: You can query the multimeter to

determine whether the front or rear input terminals are selected.

ROUTe:TERMinals? returns “FRON” or “REAR”

Page 61

Chapter 3 Features and Functions

Measurement Configuration

Autozero

When autozero is enabled (default), the multimeter internally disconnects the input signal following each measurement, and takes a zero reading. It then subtract s the zer o re a din g from the preceding reading. This prevents offset voltages present on the multimeter’s input circuitry from affecting measurement accuracy.

When autozero is disabled, the multimeter takes one zero re ad in g an d subtracts it from all subsequent measurements. It takes a new zero reading each time you change the function, range, or integration time.

Applies to dc voltage, dc current, and 2-wire ohms measurements only. Autozero i s e na b led when you select 4-wire ohms or ratio me asurements.

• The autozero mode i s stor ed in volatile memory; the multimeter

automatically enables autozero when power has been off or after a remote interface reset.

• Front-Panel Operation: The autozero mode is set indirectly when you

set the resolution.

Resolution Choices

Fast 4 Digit

* Slow 4 Digit

Fast 5 Digit

* Slow 5 Digit (default)

Fast 6 Digit

Slow 6 Digit

* These settings configure the multimeter just as if you had pressed the corresponding “DIGITS” keys from the front panel.

• Remote Interface Operation: The OFF and ONCE parameters have a

similar effe ct . Autozero Autozero

ONCE issues an immediate zero measurement.

Integration Time

0.02 PLC 1 PLC

0.2 PLC 10 PLC

10 PLC 100 PLC

Autozero

Off On

On On

OFF does not issue a new zero measurement.

ZERO:AUTO {OFF|ONCE|ON}

Page 62

Chapter 3 Features and Functions

Measurement Configuration

Autozero

(continued)

The following table shows the relationship between integration time and autozero settings from the remote interface and the corresponding front-panel settings.

From 34401A Specifications:

Remote Configuration

NPLC: 100 Autozero: On Digits Displayed: 6

⁄

NPLC: 100 Autozero: Off Digits Displayed: 6

⁄

NPLC: 10 Autozero: On Digits Displayed: 6

⁄

NPLC: 10 Autozero: Off Digits Displayed: 6

⁄

NPLC: 1 Autozero: On Digits Displayed: 5

⁄

NPLC: 1 Autozero: Off Digits Displayed: 5

⁄

NPLC: 0.2 Autozero: On Digits Displayed: 5

⁄

NPLC: 0.2 Autozero: Off Digits Displayed: 5

⁄

NPLC: 0.02 Autozero: On Digits Displayed: 4

⁄

NPLC: 0.02 Autozero: Off Digits Displayed: 4

⁄

Front-Panel Equivalent

Slow 6 digits

N/A

Fast 6 digits Slow 5 digits

N/A

Slow 4 digits

N/A

Fast 5 digits

N/A

Fast 4 digits

Digits Displayed

N/A

⁄

N/A

⁄

N/A

⁄

N/A

⁄

N/A

⁄

Readings/Sec

N/A

0.6

N/A

300

N/A

1000

See the Agilent 34401A specifications listed on page 217.

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Chapter 3 Features and Functions

Measurement Configuration

Ranging

You can let the multimeter automatically select the range using autoranging or you can select a fi xed range using manual ra nging. Autoranging is convenient because the multimeter automatically selects the appropriate range for each measurement. However, you can use manual ranging for faster measurements since the multimeter does not have to determine which range to use for each measurement.

• The selected mode (a u to or manu a l ran ge ) is store d in volatile

memory; the multimeter returns to autoranging when power has been off or after a remote interface reset.

• Autorange t h re sholds:

Down range at <10% of range Up range at >120% of range

• If the input signal is greater than the present range can measure, the

multimeter gives a n overload indication: “ or “9.90000000E+37” from the remote interface.

• For frequen cy and period measuremen t s, th e mult im eter uses one

“range” for all inputs between 3 Hz and 300 kHz. The multimeter determines an internal resolution based on a 3 Hz signal. If you query the range, the multimeter will respond with “3 Hz”. With no input signal applied, frequency and period measurements return “0”.

OVLD” from the front panel

• The range is fixed for continuity tests (1 kΩ range) and diode tests

(1 Vdc range with 1 mA current source output).

• For ratio measurements, the specified range applies to the signal

connected to the selected for reference voltage measurements on the

Input terminals. Autoranging is automatically

Sens e terminals.

Ranging is local to the selected function. This means that you can select the ranging method (auto or manual) for each function independently. When manually ranging, the selected range is local to the function; the multimeter rem em b ers the range when you switch between functions.

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Chapter 3 Features and Functions

Measurement Configuration

Ranging

(continued)

• Front-Panel Operation: Use the front-panel RANGE keys to select

autoranging or manual ranging. For frequency and period measurements from the front panel, ranging applies to the signal’s input voltage, not its frequency.

See also “To Select a Range,” on page 20.

• Remote Interface Operation: You can se t the range using any of the

foll owing co m m a nds.

CONFigure:<

MEASure:<

function>:RANGe {<range>|MINimum|MAXimum}

function>:RANGe:AUTO {OFF|ON}

function> {<range>|MIN|MAX|DEF},{<resolution>|MIN|MAX|DEF}

function>? {<range>|MIN|MAX|DEF},{<resolution>|MIN|MAX|DEF}

Page 65

Chapter 3 Features and Functions

Math Operations

There are five mat h oper a tion s av ai la ble, on ly one of w hich can be enabled at a time. Each math operation performs a mathematical operation on ea ch re a din g or stor es dat a on a series of re adi n gs. The selected math operation remains in effect until you disable it, change functions, turn off the power, or perform a remote interface reset. The math ope rat ions use one or more inter nal reg i ste rs. You can preset the values in some of the registers, while others hold the results of the math operat ion .

Null Min -Max dB dBm Limit

The following table shows the math/measurement function combinations allowed. Each “

X” indicates an allowable combination. If you choose a

math operation that is not allowed with the present measurement function, math is turned off. If you select a valid math operation and then change to one that is invalid, a “Settings conflict” error is generated from the remote interface.

DC V

X X X X X

AC V

X X X X X

DC I

X X

AC I

X X

Ω

X X

Ω

X X

Freq

X X

Per

Con t Dio d e Ratio

X X

From the front pan el , you enabl e a math oper at ion by pr ess ing t he appropriate key. The exception is Limit Test which you enable using the

LIMIT TEST command in the MATH MENU.

From the remote interface, the math operations and registers are controlled using commands within the

CALCulate command

subsystem. First, select the math operation you want to use (the default function is null):

CALCulate:FUNCtion {NULL|DB|DBM|AVERage|LIMit}

Then, enable the selected math function by turning the math state on:

CALCulate:STATe ON

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Chapter 3 Features and Functions

Math Operations

Min–Max Operation

The min-max operation stores the minimum and maximum readings during a series of measurements. The multimeter then calculates the average of all readings and records the number of readings taken since min-max was enabled.

Applies to all measurement functions, except continuity and diode.

• After you enable min-max, the first reading that the multimeter

takes is stored as both the minimum and maximum value. The minimum is replaced with any subsequent value that is less. The maximum is replaced with any subsequent value that is greater.

• The multimeter displays “MIN” or “MAX” and beeps (if the front-pan el

beeper is enabled) whenever a new minimum or maximum is found. It is possible that the multimeter will beep even if the displayed reading does not change; this is because the multimeter’s internal resolution may be greater than the displayed resolution. See also

“Beeper Control,” on page 88.

• The minimum, maximum, average, and count are stored in volatile

memory; the multimeter clears the valu es when m in-ma x is t urned on, when power has been off, or after a remote interface reset.

• Front-Panel Operation: After enabling min-max, you can read the

stored minimum, maximum, average, and count by pressing

Shift > (Menu Recall). Turning on the menu does not disa b l e

the min-max operation; the multimeter will resume taking measurements when you turn off the menu.

1: MIN-MAX (MATH MENU)

See also “To Store Minim um and Maximum Reading s,” on page 39.

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Chapter 3 Features and Functions

Math Operations

• Remote Interface Operation: You can use the following commands to

make min-max measurements.

CALCulate:FUNCtion AVERage CALCulate:STATe {OFF|ON} CALCulate:AVERage:MINimum?

CALCulate:AVERage:MAXimum? read the maximum value CALCulate:AVERage:AVERage? read the average of all readings CALCulate:AVERage:COUNt? read the count

read the minimum value

A new command is available starting with firmware Revision 2 which allows you to take readings using internal memory. This command may be useful with the min-max operation since it all ows you to deter mine the averag e of a series of readings wit hout storing the individual values.

DATA:FEED RDG_STORE, "" do not store readings DATA:FEED RDG_STORE, "CALCulate" store readings (default)

See page 126 for more information on using the

INITiate without storing them in

DATA:FEED command.

Null (Relative) Operation

When making null measurements, also called relative, each reading is the difference b etw een a stor ed n ull va lue and the inpu t sig n al. One possible application is in making more accurate two-wire ohms measurements by nulling the test lead resistance.

Result = reading – null value Applies to al l measurement fun ctions, excep t co ntinuity, di ode, and ratio.

• The null value is adjustable and you can set it to any value between

0 and

±120% of the highest range, for the present function.

• The null value is stored in volatile memory; the value is cleared

when power has been off, after a remote interface reset, or after a function change.

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Chapter 3 Features and Functions

Math Operations

Null (Relative)

(continued)

• The null value is stored in the m ultim e t er ’s Nu ll Regis ter . Ther e a re

two ways you can specify the null value. First, you can enter a specific num ber into the register from the fr on t-pa n el m en u or fr om the remote interface. Any previously stored value is replaced with the new value. If you are operating the multimeter from the front panel,

entering a nul l va lue also turns on the null functio n.

The second way to enter the null value is to let the multimeter store the first reading in the register. After you enable null, the first

reading displayed will be zero (if you have not changed the value stored in the register). If you entered a number into the register, as

described in the paragraph above, the first reading does not overwrite the stored valu e.

• Front-Panel Operation: After enabling null, you can edit the stored

null value by pressing

Shift > (Menu Recall). Any previously

stored value is replaced with the new value. Turning on the menu does not disable the null operation; the multimeter will resume taking measurements when you turn off the menu.

2: NULL VALUE (MATH MENU)

See also “To Make Null (Rel ative) Measurements,” on page 38.

• Remote Interface Operation: You can use the following commands to

make null measurements. Math must be enabled before you can store

a value in the Nu ll Re g is ter .

CALCulate:FUNCtion NULL CALCulate:STATe {OFF|ON} CALCulate:NULL:OFFSet {<

value>|MINimum|MAXimum}

The following pro gra m se gme nt sho ws t he prop er orde r tha t you should execute the commands to enable null and set an offset value.

CALC:FUNC NULL CALC:STAT ON CALC:NULL:OFFS -2.0

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Chapter 3 Features and Functions

Math Operations

dB Measurements

Each dB measurement is the difference between the input signal and a stored relative value, with both values converted to dBm.

dB = readi ng in dBm – relative value in dBm Applies to dc volta ge an d ac voltag e meas u reme n ts onl y.

• The relative value is adjustable and you can set it to any value

between 0 dBm and

±200.00 dBm.

• The relative value is stored in volatile memory; the value is cleared

when power has been off, after a remote interface reset, or after a function change.

• The relative value is stored in the multimeter’s dB Relative Register.

There are two w ays yo u ca n spec i fy the r el at iv e valu e. First , you can enter a specific nu mb er into the re gis ter fr om the fr on t -pan el men u or from the remote interface. Any previously stored value is replaced with the new value. If you are operating the multimeter from the front

panel, entering a relative va lue also turns on the dB function.

The second way to enter the relative value is to let the multimeter take the first reading, convert it to dBm, and store that value in the register. Changing the dBm reference resistance (see page 68) does not change the s t ored re l at ive valu e. Aft er you ena b le dB, the first

readin g ta k en will be 0 dB (if you have not chan g ed th e valu e sto re d in the register). If you entered a number into the register, as described in the paragraph above, the first reading does not overwrite t he store d va lu e.

• Front-Panel Operation: After enabling dB, you can edit the stored

rela tive valu e b y pressing

Shift > (Menu Recall). Any prev iously

stored value is replaced with the new value. Turning on the menu does not disable the dB operation; the multimeter will resume taking measurements when you turn off the menu.

3: dB REL (MATH MENU)

See also “To Make dB Measurements,” on page 40.

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Chapter 3 Features and Functions

Math Operations

• Remote Interface Operation: You can use the following commands to

make dB measurements. Math must be enabled b efore you can store a

value to the Relative Register.

CALCulate:FUNCtion DB CALCulate:STATe {OFF|ON} CALCulate:DB:REFerence {<

value>|MINimum|MAXimum}

dBm Measurements

The dBm operation calculates the power delivered to a resistance referenced to 1 milliwatt.

dBm = 10

× Log

( reading2 / reference resistance / 1 mW )

Applies to dc volta ge an d ac voltag e meas u reme n ts onl y.

• You can choose from 17 different reference resistance values.

The factory setting for the referenc e resi st a nce is 600

Ω.

The choice s are: 50, 75, 93, 110, 124, 125, 135, 150, 250, 300, 500,

600, 800, 900, 1000, 1200, or 8000 ohms.

• The reference resistance is stored in non-volatile memory, and does not

change when power has been off or after a remote interface reset.

• Front-Panel Operation: After enabling dBm, you can select a new

reference resistance by pressing

Shift > (Menu Recall). Turning

on the menu does not disable the dBm operation; the multimeter will resume taking measurements when you turn off the menu.

4: dBm REF R (MATH MENU)

See also “To Make dBm Measurem ents,” on page 41.

• Remote Interface Operation: You can use the following commands to

make dBm measurements.

CALCulate:FUNCtion DBM CALCulate:STATe {OFF|ON} CALCulate:DBM:REFerence {<

value>|MINimum|MAXimum}

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Chapter 3 Features and Functions

Math Operations

Limit Testing

The limit test operation enables you to perform pass/fail testing to upper and lower limits that you specify.

Applies to all measurement functions, except continuity and diode tests.

• You can set the upper and lower limits to any value between 0 and

±120% of the highest range, for the present function. The upper limit

selected should always be a more positive number than the lower limit. The default upp er and lower limits are both “0”.

• The upper and lower limits are stored in volatile memory; the

multimeter sets both limits to “0” when power has been off, after a remote interface reset, or after a function change.

• You can configure the multimeter to generate a service request (SRQ)

on the first occurrence of a failed reading. See “The SCPI Status Model,” starting on page 134 for more information.

• Front-Panel Operation: The multimeter displays “OK” for each

reading that is within the specified limits. It displays “

HI” or “ LO” for

each reading that exceeds the upper or lower limit. The multimeter beeps once (if the front-panel beeper is enabled) on the first occurrence of a failed reading after a good reading. See also “Beeper

Control,” on page 88.

5: LIMIT TEST (MATH MENU) enable or disab le limit test 6: HIGH LIMIT (MATH MENU) set the upper limit 7: LOW LIMIT (MATH MENU) set the lower limit

You can also turn off limit test by selecting a diffe rent math operatio n from the front pane l (only one m ath oper ation can b e enab led at a tim e ).

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Chapter 3 Features and Functions

Math Operations

Limit Testing

(continued)

• Remote Interface Operation: You can use th e f oll owing comman ds for

limit testing.

CALCulate:FUNCtion LIMit CALCulate:STATe {OFF|ON} CALCulate:LIMit:LOWer {< CALCulate:LIMit:UPPer {<

• There are two unu s ed pin s on the RS-232 interface co nnec t or whi c h

value>|MINimum|MAXimum} value>|MINimum|MAXimum}

are available to indicate the pass/fail status of readings taken with limit testing. To configure these pins for limit testing, you must install two jumpers inside the multimeter. See the Service Guide for

more informa tion.

A low-going pulse is output to pin 1 for each reading that is within the specified limits. A low-going pulse is output to pin 9 for each reading that exceeds the upper or lower limit.

5 V

0 V

Pin 1: Pass Output Pin 9: Fail Output

2 ms

minimum

Caution Do not use the RS-232 interface if you have configured the multimeter to

output pass/fail signals on pins 1 and 9. Internal components on the RS-232 interface circuitry may be damaged.

Page 73

Chapter 3 Features and Functions

Triggering

The multimeter’s triggering system allows you to generate triggers either manually or automatically, take multiple readings per trigger, and insert a delay before each reading. Normally, the multimeter will take one reading each time it receives a trigger, but you can specify multiple readings (up to 50,000) per trigger.

You can trigger the multimeter from the front panel using a single trigger, an external trigger, or auto triggering. Single triggering takes one reading each time you press the triggering is like single triggering, but the multimeter waits for a pulse on the rear-panel Ext Trig (external trigger) terminal before taking a readi ng. Auto triggeri ng t a ke s continuous readi ngs at the fastest rate possible for the present configu ration. Se e also “To Trigger

the Multimeter,” on page 42.

Triggering the multimeter from the remote interface is a multi-step process that offers triggering flexibility.

Single key. External

• First, you must configure the multimeter for the measurement by

selecting the function, range, resolution, etc.

• Then, you must specify the source from which the multimeter will

accept the trigger. The multimeter will accept a software (bus) trigger from the remote interface, a hardware trigger from the Ext Trig terminal, or an immediate internal trigger.

• Then, you must make sure that the multimeter is ready to accept a

trigger from the specified trigger source (this is called the

wait-for-trigger st ate) .

The diagram on the next page shows the multimeter’s triggering system.

Page 74

Chapter 3 Features and Functions

Triggering

Agilent 34401A Trigg ering System

Initiate Triggering

MEASure? READ? INITiate

Trigger Source

TRIGger:SOURce IMMediate TRIGger:SOURce EXTernal TRIGger:SOURce BUS Front-panel “Single” key

Idle State

Wait-for Trigger State

Trigger Delay

TRIGger:DELay

Sample ( ∗ ) Annunciator

Delay

Measurement Sample

Sample Count

≠ 1

Trigger Count ≠ 1

Page 75

Chapter 3 Features and Functions

Triggering

Trigger Source Choices

You must specify the source from which the multimeter will accept a trigger. From the front panel, the multimeter will accept a single trigger, a ha rd wa re trigger from the Ext Trig terminal, or continuously take readings using auto trigger. At power-on, auto triggering is used. From the remote interface, the multimeter will accept a software (bus) trigger, a ha rd wa re trigger from the Ext Trig terminal, or an immediate internal trigger. The measurement.

Q (sample) annunciator turns on during each

• The trigger so urce is stored in volatile memory; the source is set to

auto trigger (front panel) or immediate (remote interface) when power has been off or after a remote interface reset.

• To select the trigger source from the remote interface, use the

foll owing co m m a nd. The automatically set the trigger source to

TRIGger:SOURce {BUS|IMMediate|EXTernal}

Auto Triggering In the auto trigger mode (front panel only), the multimeter continuously takes readings at the fastest rate possible for the present configuration. This is the power-on trigger source for front-panel operation.

Single Triggering In the single trigger mode (front panel only), you can manually trigger the multimeter by pressing The multimet er tak es one r eadi n g, or the spec i fied n umber of readings (sam ple c ou nt) , eac h tim e yo u pres s the key . The annunciator turns on when the multimeter is waiting for a trigger.

The front-panel

Single key is disabled when in remote.

CONFigure and MEASure? commands

IMMediate.

Single .

Tri g

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Chapter 3 Features and Functions

Triggering

External Triggering In the external trigger mode, the multimeter will accept a hardware trigger applied to the Ext Trig terminal. The multimet er tak es one r eadi n g, or the spec i fied n umber of readings (sample count), each time Ext Trig receives a low-true pulse.

See also “External Tri gger Terminal,” on page 83.

• The multimeter buffers one external trigger. This means that if the

multimeter is taking a reading and another external trigger occurs, that trigger is a ccepted (a “Trigger ignored ” error is not reported). After the reading in progress is complete, the stored trigger satisfies the trigger source and then the trigger is issued.

• Front-Panel Operation: The external trigger mode is like the single

trigger mode except that you apply the trigger to the Ext Trig terminal. Pressing

enables the external trigger mode. The

Single to enable the single trigger mode also

Tri g annunciator turns on

when the multimeter is waiting for an external trigger.

The front-p an el

• Remote Interface Operation:

Single key is disabled when in remote.

TRIGger:SOURce EXTernal

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Chapter 3 Features and Functions

Triggering

Internal Tr igg ering In the internal trigger mode (r em ote interface only), the trigger signal is always present. When you place the multimeter in the wait-for-trigger state, the trigger is issued immediately. This is the power-on trigger source for remote interface operation.

To select the internal trigger source, send the following command.

CONFigure and MEASure? commands automatically set the

The trigger source to

IMMediate.

TRIGger:SOURce IMMediate

Software (Bus) Triggering The bus trigger mode is available only from the remote interface. This mode is similar to the single trigger mode from the front panel, but you trigger the multimeter by sending a bus trigger command.

• To select the bus trigger source, send the following command.

TRIGger:SOURce BUS

• To trigger the multimeter from the r emote in terface (GPIB or RS-232),

send the

*TRG (trigger) com ma n d. The *TRG command will not be

accepted unless the multimeter is in the wait-for-trigger state.

• You can also trigger the multimeter from the GPIB interface by

sending the

IEEE-488 Group Execute Trigger (GET) message.

The multimeter must be in the wait-for-trigger state. The following statement shows how to sen d a

GET using BASIC.

TRIGGER 722 Group Execute Trigger

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Chapter 3 Features and Functions

Triggering

The Wait-for-Trigger State

After you have configured the multimeter and selected a trigger source, you must place the multimeter in the wait-for-trigger state. A trigger will not be accepted until the multimeter is in this state. If a trigger signal is present, and if multimeter is in the “wait-for-trigger” state, the measurement sequence begins and readings are taken.

The “wait-for-t rigger” state is a term used prima rily for remote interface operation. From the front panel, the multimeter is always in the “wa it-for- trigger ” state and will accep t trig g er s at an y time , u nl ess a measurement is already in progress.

You can place the multimeter in the “wait-for-trigger” state by executing any of the following commands from the remote interface.

MEASure? READ? INITiate

The multim eter re qui res approximately 20 ms of set-up time after you

send a comm a nd to change to the “wait-for-trigger” state. Any triggers

that occur during this set-up time are ignored.

Halting a Measurement in Progress

You can send a device clear at any time to halt a measurement in progress and place the multimeter in the “idle state.” The following statement shows how to send a device clear over the using BASIC.

CLEAR 722 IEEE-488 Device Clear

A device clear does not affect the configuration of the triggering system. The trigger source, sample count, trigger delay, and number of triggers are not changed.

GPIB interface

Page 79

Chapter 3 Features and Functions

Triggering

Number of Samples

Normally, the multimeter takes one reading (or sample) each time it receives a tr i gger from the selected trigger source (if t he multimeter is in the wait-for-trigger state). You can, however, instruct the multimeter to take multiple readings for each trigger received.

• Number of samples: 1 to 50,000. The default is 1 sample p er tr ig g er .

• The selected num ber of samples is stored in volatile memory; the

multimeter sets the sample count to 1 when power has been off or after a remote interface reset. The commands automatically set the sample count to 1.

• Front-Panel Operation:

3: N SAMPLES (TRIG MENU)

• Remote Interface Operation:

SAMPle:COUNt {<value>|MINimum|MAXimum}

CONFigure and MEASure?

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Chapter 3 Features and Functions

Triggering

Number of Triggers

Normally, the multimeter will accept only one trigger before returning to the “idle” trigger state. You can, however, instruct the multimeter to accept multiple triggers.

This feature is available only from the remote interface. If you set the trigger c ou nt and th e n go to loc al (fr on t panel), the mult ime te r ign or e s the trigg er count setting; when you return to remote, the trigger count returns to the va lue you selected.

• Number of triggers: 1 to 50,000. The defa ul t is 1 tr ig g er.

• The selected num ber of t rigg er s is stored in volatile memory; the

multimeter sets the trigger count to 1 when power has been off or after a remote interface reset. The commands automatically set the trigger count to 1.

• Remote Interface Operation:

TRIGger:COUNt {<value>|MINimum|MAXimum|INFinite}

CONFigure and MEASure?

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Chapter 3 Features and Functions

Triggering

Trigger Delay

You can insert a delay between the trigger signal and each sample that follows. This may be useful in applications where you want to allow the input to settle before taking a reading, or for pacing a burst of readings. If you do not specify a trigger delay, the multimeter automatically selects a delay for you.

• Delay range: 0 to 3600 seconds. The default trigger delay is

automatic; the d elay is det er mined b y fu nc tion, ran ge , inte gr ation time, and ac filter setting (see also “Automatic Trigger Delays,” on page 81).

• The trigger delay is stored in volatile memory; the multimeter selects

an automatic trigger delay when power has been off or after a remote interface reset. The

CONFigure and MEASure? commands

automatically set the trigger delay to automatic.

• If you specify a delay other than automatic, that same delay is used

for all functions and ranges.

• If you have configured the multimeter to take more than one reading

per trigger (sample count > 1), the specified trigger delay is inserted between the trigger and each reading.

• Front-Panel Operation: You can use an automatic trigger delay or

you can specify a delay in seconds.

2: TRIG DELAY (TRIG MENU)

If an automatic trigger delay is enabled, “AUTO” is displayed momentarily before the actual number of seconds is displayed.

--- AUTO ---

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Chapter 3 Features and Functions

Triggering

Trigger Dela y

(continued)

• Front-Panel Operation (continued)

To set the delay to 0 seconds, select the “parameter” level of the

DELAY

the right side of the display. Press

command. Move the flashing cursor to the “units” location on

∨ until ZERO DELAY is reached,

then press Menu Enter.

ZERO DELAY

To select the automatic trigger delay, select the “parameter” level of the

TRIG DELAY command. Move the flashing cursor to the

“units” location on the right side of the display. Press

AUTO DELAY is reached, th en press Menu Enter.

∨ until

AUTO DELAY

• Remote Interface Operation:

You can use the following command to set the trigger delay.

TRIGger:DELay {<seconds>|MINimum|MAXimum}

You can use the following command to set an automatic trigger delay.

TRIG

TRIGger:DELay:AUTO {OFF|ON}

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Chapter 3 Features and Functions

Triggering

Automatic Trigger Delays

If you do not specify a trigger delay, the multimeter selects an automatic delay for you. The delay is determined by function, range, integration time, and ac filter setting.

• DC Voltage and DC Cu rrent (for all ranges ):

Integration Time

NPLC ≥ 1 NPLC < 1

• Resistance (2-wire and 4-wire):

Rang e

100 Ω 1 kΩ 10 kΩ 100 kΩ 1 MΩ 10 MΩ 100 MΩ

• AC Voltage and AC Cu rrent (for all ranges) :

Remote or single/external trigger

AC F ilter

Slow Medium Fast

Trigger Delay

1.5 ms

1.0 ms

Trigger Delay (For NPLC ≥ 1)

1.5 ms

1.5 ms 15 ms 100 ms 100 ms

Trigger Delay

7.0 sec

1.0 sec 600 ms

Range

100 Ω 1 kΩ 10 kΩ 100 kΩ 1 MΩ 10 MΩ 100 MΩ

Front panel with auto tr igger ON

AC Filter

Slow Medium Fast

Trigger Delay (For NPLC < 1)

1.0 ms

1.0 ms 10 ms 100 ms 100 ms

Trigger Delay

1.5 sec 200 ms 100 ms

• Frequenc y and Pe ri od :

Remote or single/external trigger

Trigger Delay

1.0 sec

Front panel with auto trigger ON

Trigger Delay

0 sec

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Chapter 3 Features and Functions

Triggering

Reading Hold

The reading hold feature allows you to capture and hold a stable reading on the front-panel display. This is especially useful in situations where you want to take a reading, remove the test probes, and have the reading remain on the display. When a stable reading is detected, the multimeter emits a beep (if the front-panel beeper is enabled) and holds the reading on the display. See also “Beeper Control,” on page 88.

The reading hold feature is available only from the front panel. If you go to remote when reading hold is enabled, the multimeter ignores it; when you return to loc al (fr on t panel), reading hold is enable d aga in .

• Reading hold has an adjustable sen s iti vit y b an d (adj u st ab le only fr om

the front panel) to allow you to select which readings are considered stable enough to be displa yed. The band is expressed as a perc en t of reading, on the selected range. The multimeter will capture and display a new value only after three consecutive readings are within t he band.

Select one of these values: 0. 01%, 0.10% (default), 1.00%, or 10.00% of reading. For example, assume that the 1.00% band is selected and a 5 volt signal is applied to the multimeter. If three consecutive readings are between 4.975 volts and 5.025 volts, the display will show a new reading.

• The sensitivity band is stored in volatile memory; the multimeter sets

the band to 0.10% when power has been off or after an interface reset.

• If the multimeter is in autorange when you enable reading hold,

it will autorange to the correct range. If the multimeter is in the manual r a ng e m o de , th e s am e f ixed range w i ll b e u se d for rea din g hold.

• When reading hold is enabled, the input resistance is automatically

set to 10 M

Ω (AUTO OFF) for all dc voltage ranges. This helps to

minimize noise pickup when the test leads are open-circuit.

• For certain applications, it may be useful to use reading hold with

reading memory. See also “Reading Memory,” on page 84.

• Front-Panel Operation: After enabling reading hold, you can select a

different sensitivity band by pressing

Shift > (Menu Recall).

1: READ HOLD (TRIG MENU)

See also “To Use Reading Hold,” on page 43.

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Chapter 3 Features and Functions

Triggering

Voltmeter Complete Terminal

The rear-pan el VM Comp (voltmeter complete) terminal provides a low-true pulse after the completion of each measurement. Voltmeter complete and external trigger (see below) implement a standard hardware handshake sequence between measur ement and s witching devices.

5 V

0 V

Output

Approximately 2 µs

External Trigger Terminal

You can trigger the multimeter by applying a low-true pulse to the rear-panel Ext Trig (external trigger) terminal. To use this terminal from the remote interface, you must select the external trigger source

TRIGger:SOURce EXTernal).

(

5 V

0 V

You can use a simple switch to generate an external trigger using the Ext Trig input as shown below.

Input

>1 µs

Ext Trig

Page 86

Chapter 3 Features and Functions

System-Related Operations

This sectio n gi ve s information on topics such as reading memo ry, errors, self-test, and front-panel display control. This information is not directly related to making measurements but is an important part of operating the multimeter.

Reading Memory

The multimeter can store up to 512 readings in internal memory. Readings are stored in first-in-first-out ( returned is the first reading stored. The reading memory feature is

available only from the front panel.

• You can use reading memory with all functions, math operations, and

also reading hold. After you have enabled reading memory, you can change the function. Be aware, however, that the function labels

VDC, OHM, etc. ) are not stored with the reading.

(

FIFO) order. The first reading

• Readings taken while reading memory is enabled are stored in

volatile memory; the multimeter clears the stored readings when reading memory is turned on again, when power has been off, after a self-test, or after a remote interface reset.

• You can use reading memory with auto trigger, single trigger,

external trigger, and reading hold. If you configure the multimeter for multiple readings per trigger, the specified number of readings are stored in memory each time a trigger is received.

• Front-Panel Operation:

1: RDGS STORE (SYS MENU) store readings in memory 2: SAVED RDGS (SYS MENU) read the stored rea dings

Reading memory is automatically turned off when you go to the “parameter” level in the menu to recall the readings. See also “To Use

Reading Memory,” on page 46.

• Remote Interface Operation: The INITiate command uses reading

memory to store readings prior to a

FETCh? command. You ca n q uery

the number of stored readings in memory by sending the

DATA:POINts? command from the remote interface.

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Chapter 3 Features and Functions

System-Related Operations

Error Conditions

When the front-panel ERROR annunciator turns on, one or more command syntax or hardware erro rs ha ve been detected . A reco rd of up to 20 errors is stored in the multimeter’s error queue. See chapter 5,

“Error Messages,” for a complet e li sting of the errors.

• Errors are retrieved in first-in-first-out (FIFO) order. The first

error returned is the first error that was stored. Wh en you have read al l error s from th e queue, the The multimeter beeps once each time an error is generated.

ERROR annunciator turns off.

• If more than 20 errors have occurred, the last error stored in the

queue (the most recent error) is replaced w ith -350, “Too many errors”. No additional e rrors are stored until you remove errors from the queue. If no errors have occurred when you read the error queue, the multime ter respon ds with +0, “No error ”.

• The error queue is cleared when power has been off or after a *CLS

(clear statu s) co m ma nd has been exec u t ed. The *RST (reset) command does not clear the error queue.

• Front-Panel Operation:

3: ERROR (SYS MENU)

If the ERROR annunciat or is on, press Shift < (Recall Menu) to read the error s stored in the queue. The erro rs are listed horizontally on the “parameter” level. All errors are cleared when you go to the “parameter” level and then turn off the menu.

ERR 1: -113

First error in queue

• Remote Interface Operation:

Error code

SYSTem:ERRor?

Reads one error from the error queue

Errors have the following format (the error string may contain

up to 80 characters):

-113,"Undefined header"

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Chapter 3 Features and Functions

System-Related Operations

Self-Test

A power-on self-test occurs automatically when you turn on the multimeter. This limited test assures you that the multimeter is operational. This sel f-tes t does no t perf or m the ex t en sive set of anal og tests that are included as part of the complete self-test described below.

A complete self-test run s a series of tes ts an d tak es ap pr ox ima tel y 15 seconds to execute. If all test s p a s s, you can have a high confid ence that the multimeter is operational.

• The results of the complete self-test are stored in internal reading

memory (see page 84). Memory is cleared a s the self -t est stores this informati on. Other than clea ri ng memory, the co m plete self-test does not alter the state of the multim eter .

• If the complete self-test is successful, “PASS” is displa yed on the fr on t

panel. If the self-test fails, “ annunciator turns on. See the Service Guide for instructions o n returning the multimeter to Agilent for service.

FAIL” is displayed and the ERROR

• Front-Panel Operation: You can perform some of the tests (complete

self-test) individually or you can perform all tests together at once.

4: TEST (SYS MENU)

Another way to perform the complete front-panel self-test is as follows: Hold down

Shift as you press the Power switch to turn on the

multimeter; hold down the key for more than 5 seconds. The selftest will begin when you release the key.

• Remote Interface Operation:

*TST?

Returns “0” if the self-test is successful, or “1” if it fails.

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Chapter 3 Features and Functions

System-Related Operations

Display Control

To speed up your measurement rate, or for security reasons, you may want to turn off the front-panel display. From the remote interface, you can also display a 12-character message on the front panel.

• When the display is turned off, readings are not sent to the display

and all display annunciators except

Front-panel operation is otherwise una ffected by turning off the display.

• The display state i s stor ed in volatile memory; the display is enabled

when power has been off or after a remote interface reset.

• You can display a message on the front panel by sending a

command from the remote interface. The multimeter can display up

to 12 characters of the message on the front panel; any additional

characters are truncated. Commas, periods, and semicolons share a

display space with the preceding character, and are not considered

individual characters. When a message is displayed, readings are not

sent to the display.

• Sending a message to the display from the remote interface overrides

the display state; this means that you can display a message even if

the display is turned off.

ERROR and Shif t are disabled.

• Front-Panel Operation:

5: DISPLAY (SYS MENU)

The display always turns on for menu operation; this means that

even when the display is turned off, you can still operate the menu.

• Remote Interface Operation:

DISPlay {OFF|ON} disable/enable the display

DISPlay:TEXT <quoted string> display the string enclosed in quotes

DISPlay:TEXT:CLEar clear the displayed message

The following command string shows how to display a message on the

front panel.

"DISP:TEXT ’HELLO’"

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Chapter 3 Features and Functions

System-Related Operations

Beeper Control

Normally, the multimeter will emit a tone whenever certain conditions are met from the front panel. For example, the multimeter will beep when a stable reading is captured in reading hold. You may want to disable the front-panel beeper for certain applications.

• When you disable the beeper, the multimeter will not em it a t one when:

1) a new minimum or maximum is found in a min–max test.

2) a stable reading is captured in reading hold.

3) a limit is exceeded in a limit test.

4) a forward-biased diode is measured in the diode test function.

• Disabling the beeper has no effect on the tone generated when:

1) an error is generated.

2) the continuity thr es hol d is exc eede d.

3) you turn off the front-panel menu.

Turn ing off th e b eeper does not disable the key click ge nerated when you press a front-panel key.

• The beeper stat e is store d in non-volatile memory, and does not

change when power has been off or after a remote interface reset. The beeper is enabled when the m ultimeter is shipped fr om t he factory.

• Front-Panel Operation:

6: BEEP (SYS MENU)

• Remote Interface Operation:

SYSTem:BEEPer issue a single b eep imm ediately SYSTem:BEEPer:STATe {OFF|ON} disable/enable beeper state

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Chapter 3 Features and Functions

System-Related Operations

Comma Separato rs

The multimet er can display re adi n gs on the fr on t panel w it h or with ou t a comma separator. This featu r e is ava ilable only from the front pa nel.

08.241,53 VDC

With comma separator

• The display format is stored in non-volatile memory, and does not

(factory setting) Without comma separator

08.24153 VDC

change when power has been off or after a remote interface reset.

The comma separator is enabled when the multimeter is shipped

from the facto ry .

• Front-Panel Operation:

7: COMMA (SYS MENU)

See also “ T o Tu rn Of f the Comm a Se par at or ,” on page 37.

Firmware Revision Query

The multimeter has three micropr ocessors for control of various internal systems. You can query the multimeter to determine which revision of firmware is installed for each microprocessor.

• The multim ete r returns three numbe rs. The first numbe r i s th e

firmware revi sion number for the measurement processo r; the second

is for the input/output processor; and the third is for the front-panel

processor.

• Front-Panel Operation:

8: REVISION (SYS MENU)

• Remote Interface Operation:

REV XX-XX-XX

*IDN? returns “HEWLETT-PACKARD,34401A,0,XX-XX-X X”

Be sure to dimens io n a string variabl e with at least 35 charact ers.

Page 92

Chapter 3 Features and Functions

System-Related Operations

SCPI Language Version Query

The multimet er complies with the rules and reg ulat io ns of the presen t version of You can determine the compliance by sending a command from the remote interface.

SCPI (Standard Commands for Programmable Instruments).

SCPI version with which the multimeter is in

You cannot query the

• The following command returns the SCPI version.

SCPI version from the front panel.

SYSTem:VERSion?

Returns a string in the form “YYYY.V” where the “Y’s” represent the year of the version, and the “V” represents a version number for that year (for example, 1991.0).

Page 93

Chapter 3 Features and Functions

Remote Interface Configuration

Remote Interface C onfigur ation

This section gives information on configuring the remote interface. For additional inf or ma tion , see ch apt er 4, “ R e m ote In t er fac e Refer en c e,” starting on page 103.

GPIB Address

Each device on the GPIB (IEEE-488) interface must have a unique address. You can set the multimeter’s address to any value between 0 and 31. The address is set to “22” when the multimeter is shipped from the factor y . The

The GPIB address can be set only from the front-panel.

• The address is stored in non-volatile memory, and does not change

when power has been off or after a remote interface reset.

• You can set the address to “31” which is the talk only mode. In this

mode, the multimeter can output readings directly to a printer

without being addressed by a bus controller (over either

RS-232). For proper operation, make sure your printer is configured in

the listen always mode. Address 31 is not a valid address if you are

operating the multimeter from the

GPIB address is displayed at power-on.

GPIB or

GPIB interface with a bus controller.

If you select the

RS-232 interface and then set the GPIB address to the

talk only address (31), the multimeter will send readings over the

RS-232 interface when in the local mode.

• If you select the RS-232 interface and then set the GPIB address to the

talk only address (31), the multimeter will send readings over the

RS-232 interface when in the local mode.

• Your GPIB bus controll er has its own address. Be sure to avoid using

the b us controller’ s addres s f or any instrument on the interface bus.

Agilent controllers generally use address “21”.

• Front-Panel Operation:

1: HP-IB ADDR (I/O MENU)

See also “To Set the GPIB Address,” on page 161.

Page 94

Chapter 3 Features and Functions

Remote Interface Configuration

Remote Interface Selection

The multimeter is shipped with both an GPIB (IEEE-488) interface and an The the factory.

The remote interface can be set only from the front- panel.

• The interface selection is stored in non-volatile memory, and does not

• If you select the GPIB interface, you must select a unique address for

• If you select the RS-232 interface, you must set the baud rate and

• If you select the RS-232 interface and then set the GPIB address to the

RS-232 interface. Only one interface can be enabled at a time.

GPIB interface is selected when the multimeter is shipped from

change when power has been off or after a remote interface reset.

the multime ter . Th e

GPIB address is displayed when you tu rn on the

multimeter.

parity for the multimeter. “

RS-232” is display ed when yo u tu rn on the

multimeter.

talk only address (31), the multimeter will send readings over the

RS-232 interface when in the local mode.

• There are certain restrictions to be aware of when you are selecting

the remote interface (see also “Programming Language Selection,” on page 94). The only programming language supported on

SCPI Language 3478A Language Fluk e 8840A Language

• Front-Panel Operation:

GPIB / 488

X X

RS-232

X Not allowed Not allowed

RS-232 is SCPI.

2: INTERFACE (I/O MENU)

See also “To Select the Remote Interface,” on page 162.

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Chapter 3 Features and Functions

Remote Interface Configuration

Baud Rate Selection (RS-232)

You can select one of six baud rates for RS-232 operation. The rate is set to 9600 baud when the multimeter is shipped from the factory.

The baud rate ca n be se t only from the front-panel.

• Select one of the following: 300, 600, 1200, 2400, 4800, or 9600 baud

(factory setting).

• The baud rate selection is stored in non-volatile memory, and does not

change when power has been off or after a remote interface reset.

• Front-Panel Operation:

3: BAUD RATE (I/O MENU)

See also “To Set the Baud Rate,” on page 163.

Parity Selection (RS-232)

You can select the p a ri t y fo r RS-232 operation. The multimeter is configured for even parity with 7 data bits w hen shi pped from th e fa ctory.

The parity ca n b e set only from the fr ont-panel.

• Select one of the following: None (8 data bits), Even (7 data bits), or

Odd (7 data bits). When you set the parity, you are indirectly setting

the number of data bits.

• The parity selection is stored in non-volatile memory, and does not

change when power has been off or after a remote interface reset.

• Front-Panel Operation:

4: PARITY (I/O MENU)

See also “To Set the Parity,” on page 164.

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Chapter 3 Features and Functions

Remote Interface Configuration

Programming Language Selection

You can select one of three languages to program the multimeter from the selected remote interface. The languag e is shipped from the factor y.

• Select one of the following: SCPI, Agilent 3478A, or Fluke 8840A.

• The la n gu age se lec tio n is st ore d in non-volatile memory, and does not

change when power has been off or after a remote interface reset.

• There are certain restrictions to be aware of when you are selecting

the interface language (see also “Remote Interface Selection,” on page 92). The Agilent 3478A and Fluke 8840A/8842A languages are not sup ported on the

RS-232 interface.

SCPI when the multimeter is

SCPI Language 3478A Language Fluk e 8840A Language

• Front-Panel Operation:

GPIB / 488

X X

RS-232

X Not allowed Not allowed

5: LANGUAGE (I/O MENU)

See also “To Select the Programming Language,” on page 165.

• Remote Interface Operation:

L1 select SCPI langu ag e L2 select Agilent 3478A language L3 select Fluke 8840A language

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Chapter 3 Features and Functions

Calibration Overview

This section gives a brief introduction to the calibration features of the multimeter. For a more detailed discussion of th e calibra tion procedur es, see cha p t er 4 in the Service Guide.

Calibration Secur i ty

This feature allows you to enter a security code to prevent accidental or unauthori zed c al ibrat ions of the multimeter . When yo u firs t rec eiv e your multimeter, it is secured. Before you can calibrate the multimeter, you must unsecure it by entering the correct security code.

• The security code is set to “HP034401” w hen the multimeter is shipped

from the factory. The security code is stored in non-volatile memory,

and does not change when power has been off or after a remote

interface reset.

• To secure the multimeter from the remote interface, the security code

may contain up to 12 alphanumeric characters as shown below.

The first character must be a letter, but the remaining characters can

be letters or numbers. You do not have to use all 12 characters but

the first character must always be a letter.

A _ _ _ _ _ _ _ _ _ _ _ (12 charact ers)

• To secure the multimeter from the remote interface so that it can be

unsecured fr om the fron t pa nel , use the eig ht- ch ar a c ter format s hown

below. The first two characters must be “HP” and the remaining

characters must be numbers. Only the last six characters are

recognized from the front panel, but all eight characters are required.

(To unsecure t h e mult imet e r fr om t he front pan el , omit t he “HP” a n d

enter the remaining numbers as shown on the following pages.)

H P _ _ _ _ _ _ (8 charact ers)

If you for get your security code, you can disable the security feature by adding a jumper inside the mul timeter, and then entering a new co de. See the Service Guide for more informa tion.

Page 98

Chapter 3 Features and Functions

Calibration Overview

Calibration Security

(continued)

To Unsecure for Calibration You can unsecure the multimeter for calibration either from the front panel or remote interface. The multimet er is secur ed wh en sh ipped from the factor y, and the security co de i s s et to “

• Front-Panel Operation:

HP034401”.

1: SECURED (CAL MENU)

If the multimeter is secured, you will see the above command when you go into the in the menu, you will notice that the “

CAL MENU. (If you move across the “commands” level

2: CALIBRATE” command is

“hidden” if the multimeter is secured.) To unsecure the multimeter, select the “parameter” level of the

SECURED command, enter the

security code, then press Menu Enter.

∧000000 CODE

When you go to the “commands” level in the

CAL MENU again,

you will notice that the multimeter is unsecured. Notice also that the

2: CALIBRATE” command is no longer hidden and you can perform

“ a calibration.

1: UNSECURED

• Remote Interface Operation:

CALibration:SECure:STATe {OFF|ON},<code>

To unsecure the multimeter, send the above command with the same code used to secure. For example,

"CAL:SEC:STAT OFF,HP034401"

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Chapter 3 Features and Functions

Calibration Overview

To Secure Against Calibration You can secure the multimeter against calibration either from the front panel or remote interface. The multimet er is secur ed wh en sh ipped from the factor y, and the security co de i s s et to “

HP034401”.

Make sure you have read the security code rules on page 95 before attempti ng to secure the multimeter.

• Front-Panel Operation:

1: UNSECURED (CAL MENU)

If the multimeter is unsecured, you will see the above command when

you go into the

“parameter” level of the

CAL MENU. To secure the multimeter, select the

UNSECURED command, enter the security

code, then press Menu Enter .

∧000000 CODE

When you go to the “commands” level in the

CAL MENU again,

you will notice that the multimeter is secured. Notice also that the

2: CALIBRATE” command is now hidde n a nd you cannot perform

“

a calibration.

1: SECURED

• Remote Interface Operation:

CALibration:SECure:STATe {OFF|ON},< code>

To secure the multimeter, send the above command with the same

code as used to unsecure. For example,

"CAL:SEC:STAT ON,HP034401"

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Chapter 3 Features and Functions

Calibration Overview

Calibration Security

(continued)

To Change the Security Code To change the security code, you must first unsecure the multimeter, and then enter a new code. Make sure you have read the security code rules on page 95 before attempting to secure the mult im eter.

• Front-Panel Operation: To change the security code, first make sure

that the mul tim eter is uns ec u re d. Selec t the “parameter” level of t h e

UNSECURED command, enter the new security code, then press

Menu Enter. Changing the code from the front panel also changes the code as seen from the remote interface.

• Remote Interface Operation:

CALibration:SECure:CODE <new code>

To change the security code, first unsecure the multimeter using the old security code. Then, enter the new code. For example,

CAL:SEC:STAT OFF, HP034401 unsecure with ol d code CAL:SEC:CODE ZZ010443 enter new code

Calibration Count

You can determine the number of times that your multimeter has been calibrated. Your multimeter was calibrated before it left the factory. When you receive your multimeter, read the count to determine its initial value.

• The calibrati on co unt i s stor ed in non-volatile memory, and does not

change when power has been off or after a remote interface reset.

• The calibration count increments up to a maximum of 32,767 after

which it wra ps -ar ou nd to 0. Sinc e th e val ue i ncr em en ts by on e for each calibrat ion point, a comp lete calibrati on increases the v a l ue by several counts.

• Front-Panel Operation:

3: CAL COUNT (CAL MENU)

• Remote Interface Operation:

CALibration:COUNt?