Keysight 34420A User Manual

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Keysight 34420A Nano Volt/ Micro Ohm Meter

User’s Guide

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Notices

CAUTION

WARNING

duced in any form or by any means (including electronic storage and retrieval or translation into a foreign language) without prior agreement and written consent from Keysight Technologies as governed by United States and international copyright laws.

Trademarks

Microsoft® and WIndows® are U.S. registered trademarks of Microsoft Corporation. All other brand and product names are trademarks of their respective companies.

Manual Part Number

34420-90001

Edition

Edition 3, September 1, 2017

Printed in:

Printed in Malaysia

Published by:

Keysight Technologies Bayan Lepas Free Industrial Zone, 11900 Penang, Malaysia

Technology Licenses

The hard ware and/or software described in this document are furnished under a license and may be used or copied only in accordance with the terms of such license.

Declaration of Conformity

Declarations of Conformity for this product and for other Keysight products may be downloaded from the Web. Go to http://www.keysight.com/

go/conformity. You can then search by

product number to find the latest Declaration of Conformity.

U.S. Government Rights

The Software is “commercial computer software,” as defined by Federal Acquisition Regulation (“FAR”) 2.101. Pursuant to FAR 12.212 and 27.405-3 and Department of Defense FAR Supplement (“DFARS”) 227.7202, the U.S. government acquires commercial computer software under the same terms by which the software is customarily provided to the public. Accordingly, Keysight provides the Software to U.S. government customers under its standard commercial license, which is embodied in its End User License Agreement (EULA), a copy of which can be found at http://www.keysight.com/

find/sweula. The license set forth in the

EULA represents the exclusive authority by which the U.S. government may use, modify, distribute, or disclose the Software. The EULA and the license set forth therein, does not require or permit, among other things, that Keysight: (1) Furnish technical information related to commercial computer software or commercial computer software documentation that is not customarily provided to the public; or (2) Relinquish to, or otherwise provide, the government rights in excess of these rights customarily provided to the public to use, modify, reproduce, release, perform, display, or disclose commercial computer software or commercial computer software documentation. No additional government requirements beyond those set forth in the EULA shall apply, except to the extent that those terms, rights, or licenses are explicitly required from all providers of commercial computer software pursuant to the FAR and the DFARS and are set forth specifically in writing elsewhere in the EULA. Keysight shall be under no obligation to update, revise or otherwise modify the Software. With respect to any technical data as defined by FAR 2.101, pursuant to FAR

12.211 and 27.404.2 and DFARS

227.7102, the U.S. government acquires no greater than Limited Rights as defined in FAR 27.401 or DFAR

227.7103-5 (c), as applicable in any technical data.

Warranty

THE MATERIAL CONTAINED IN THIS DOCUMENT IS PROVIDED “AS IS,” AND IS SUBJECT TO BEING CHANGED, WITHOUT NOTICE, IN FUTURE EDITIONS. FURTHER, TO THE MAXIMUM EXTENT PERMITTED BY APPLICABLE LAW, KEYSIGHT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, WITH REGARD TO THIS MANUAL AND ANY INFORMATION CONTAINED HEREIN, INCLUDING BUT NOT LIMITED TO THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. KEYSIGHT SHALL NOT BE LIABLE FOR ERRORS OR FOR INCIDENTAL OR CONSEQUENTIAL DAMAGES IN CONNECTION WITH THE FURNISHING, USE, OR PERFORMANCE OF THIS DOCUMENT OR OF ANY INFORMATION CONTAINED HEREIN. SHOULD KEYSIGHT AND THE USER HAVE A SEPARATE WRITTEN AGREEMENT WITH WARRANTY TERMS COVERING THE MATERIAL IN THIS DOCUMENT THAT CONFLICT WITH THESE TERMS, THE WARRANTY TERMS IN THE SEPARATE AGREEMENT SHALL CONTROL.

Safety Information

A CAUTION notice denotes a hazard. It calls attention to an operating procedure, practice, or the like that, if not correctly performed or adhered to, could result in damage to the product or loss of important data. Do not proceed beyond a CAUTION notice until the indicated conditions are fully understood and met.

A WARNING notice denotes a hazard. It calls attention to an operating procedure, practice, or the like that, if not correctly performed or adhered to, could result in personal injury or death. Do not proceed beyond a WARNING notice until the indicated conditions are fully understood and met.

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Certification

Keysight Technologies certifies that this product met its published specifications at the time of shipment from factory. Keysight Technologies further certifies that its calibration measurements are traceable to the United States National Institute of Standards and Technology, to the extend allowed by that organization’s calibration facility, and to the calibration facilities of other INternational Standards Organization members.

Safety Symbols

The following symbols on the instrument and in the documentation indicate precautions which must be taken to maintain safe operation of the instrument.

Earth (ground) terminal Frame or chassis (ground) terminal

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Safety Considerations

WARNING

NOTE

Read the information below before using this instrument.

The following general safety precautions must be observed during all phases of operation, service, and repair of this instrument. Failure to comply with these precautions or with specific warnings elsewhere in this manual violates safety standards for design, manufacture, and intended use of the instrument. Keysight Technologies assumes no liability for the customer’s failure to comply with these requirements.

Only qualified, service-trained personnel who are aware of the hazards involved should remove the cover from the instrument.

For continued protection against fire, replace the line fuse only with a fuse of the specified type and rating.

Do not install substitute parts or perfrom any unauthorized modification to the product. Return the product to an Keysight Technologies Sales and Service Office for service and repair to ensure that safety features are maintained.

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Environmental Conditions

The 34420A is designed for indoor use and in an area with low condensation. The table below shows the general environmental requirements for this instrument.

Environmental condition Requirement

Temperature

Humidity

Operating condition – 0 °C to 55 °C Storage condition – –40 °C to 75 °C

Operating condition – Up to 80% RH at 40°C (non-condensing)

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Waste Electrical and Electronic Equipment (WEEE) Directive

This instrument complies with the WEEE Directive marking requirement. This affixed product label indicates that you must not discard this electrical or electronic product in domestic household waste.

Product category:

With reference to the equipment types in the WEEE directive Annex 1, this instrument is classified as a “Monitoring and Control Instrument” product.

The affixed product label is as shown below.

Do not dispose in domestic household waste.

To return this unwanted instrument, contact your nearest Keysight Service Center, or visit http://about.keysight.com/en/companyinfo/environment/takeback.shtml for more information.

Sales and Technical Support

To contact Keysight for sales and technical support, refer to the support links on the following Keysight websites:

– www.keysight.com/find/34420A

(product-specific information and support, software and documentation updates)

– www.keysight.com/find/assist

(worldwide contact information for repair and service)

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The 34420A is a 71/2 digit, high performance nanovolt, micro-ohm meter. Its combination of bench-top and system features makes this meter a versatile solution for your testing requirements now and in the future.

Convenient bench-top features

– Built-in math operations including thermistor, thermocouple and RTD

temperature measurements

– Two channel input allows ratio and difference functions for voltage

measurements

– Highly visible vacuum-fluorescent display

– Portable, ruggedized case with non-skid feet

Flexible system features

– GPIB (IEEE-488) interface and RS-232 interface are standard

– SCPI (Standard Commands for Programmable Instruments) and Keithley 181

compatibility

– Readings at up to 250 per second

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The Front-Panel at a Glance

1 Input channel select

2 Measurement function keys

3 Math operation keys

4 Filter select key

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5 Menu operation keys

6 Range/number of digits displayed keys

7 Single trigger/autotrigger/auto hold key

8 Shift / local key

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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: DIG FILTER ) 2: INTEGRATE ) 3: OCOMP W ) 4: LOW POWER W ) 5: LOW VOLT W )

6: LoV LIMIT W

B: TEMPerature MENU

1:PROBE TYPE ) 2: UNITS ) 3: RTD TYPE ) 4:RTD Ro ) 5:T/C TYPE ) 6: COLD JUNCT ) 7:JUNCT

C: MATH MENU

1: STATS ) 2: NULL VALUE ) 3: SCALE GAIN ) 4 : SCALE OFST

D: TRIGger MENU

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

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E: SYStem MENU

NOTE

1: RDGS STORE ) 2: SAVED RDGS ) 3: ERROR ) 4: TEST ) 5: CHART OUT ) 6: CHART SPAN )

7: CHART NULL ) 8: DISPLAY ) 9: COMMA ) 10: PRESET ) 11: REVISION

F: Input/Output MENU

1: GPIB ADDR ) 2: INTERFACE ) 3: BAUD RATE ) 4: PARITY ) 5: LANGUAGE

G: CALibration MENU

1: SECURED ) [1: UNSECURED] ) [2:CALIBRATE] ) [3: CHART ZERO] ) [4 : CHART GAIN] )

[5: INJECTED I] ) 6:CAL COUNT ) 7:MESSAGE

The commands enclosed in square brackets ([ ]) in the CAL MENU are "hidden" unless the meter is UNSECURED for calibration.

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Display Annunciators

Adrs Rmt Man Trig OC Off Null Stats Scale ERROR Shift Ch1 Ch2 Ch1 - Ch2 Ch1 / Ch2 W LP 2W LoV Hold Filt Mem

Turns on during a measurement. Meter is addressed to listen or talk over the GPIB interface. Meter is in remote mode (using remote interface). Meter is using manual ranging (autorange is disabled). Meter is waiting for a single trigger or external trigger. Offset compensation is turned off. A null value is being used. Math statistics operations are being used. Math scaling operations are being used. Hardware or remote interface command error(s) detected. "Shift" key has been pressed. Meter input is on Channel 1. Meter input is on Channel 2. Meter is indicating the difference between inputs on channel 1 and channel 2. Meter is indicating the ratio of the inputs on channel 1 and channel 2. Meter is measuring resistance (Ohms). Meter is using low power Ohms. Meter is using 2-wire Ohms (annunciator off indicates a 4-wire measurement). Meter is using voltage limited Ohms. Automatic reading hold is enabled. The analog and/or the digital filter is enabled. Turns on when reading memory is enabled.

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

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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 Chart recorder output terminal

(Analog out)

Use the front-panel Input / Output Menu to:

– Select the GPIB or RS-232 interface

– Set the GPIB bus address

– Set the RS-232 baud rate and parity

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5 Voltmeter complete output terminal

6 External trigger input terminal

7 GPIB (IEEE-488) interface

connector

8 RS-232 interface connector

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In This Book

NOTE

Quick Start Chapter 1 prepares the meter for use and helps you get familiar

with a few of its front-panel features.

Front-Panel Operation Chapter 2 introduces you to the front-panel menu and

describes some of the meter’s menu features.

Features and Functions Chapter 3 gives a detailed description of the meter’s

capabilities and operation. You will find this chapter useful whether you are operating the meter from the front panel or from a remote interface.

Remote Interface Reference Chapter 4 contains reference information to help

you program the meter using a remote interface.

Error Messages Chapter 5 lists the error messages that may appear as you are

working with the meter. 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 Chapter 7 discusses measurement considerations and

techniques to help you obtain the best accuracy and reduce sources of measurement error.

Specifications Chapter 8 lists the meter’s specifications and describes how to

interpret these specifications.

If you have questions relating to the operation of the meter, call 1-800-452-4844 in the United States, or contact your nearest Keysight Technologies Sales Office.

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THIS PAGE HAS BEEN INTENTIONALLY LEFT BLANK.

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Safety Symbols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3

Safety Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4

Measurement Category <valid for HH UG only - remove this> . . . . . . . .5

Environmental Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6

Regulatory Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7

Safety compliance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7

EMC compliance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7

Regulatory Markings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Waste Electrical and Electronic Equipment (WEEE) Directive . . . . . . . .9

Product category: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9

Sales and Technical Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9

1Quick Start

Quick Start . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20

To Prepare the Meter For Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21

If the Meter Does Not Turn On . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

To Adjust the Carrying Handle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24

To Make Input Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

To Measure Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27

To Measure Temperature With Thermistors . . . . . . . . . . . . . . . . . . . . .28

To Measure Temperature With RTDs . . . . . . . . . . . . . . . . . . . . . . . . . . .29

To Measure Temperature With Thermocouples . . . . . . . . . . . . . . . . . . 30

To Select a Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31

To Set the Number of Digits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32

To Set the Integration Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33

Front-Panel Display Formats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34

To Rack Mount the Meter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35

2 Front-Panel Operation

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Front-Panel Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

Front-Panel Menu Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

A Front-Panel Menu Tutorial . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

To Select an Input Channel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

To Select a Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

To Set or Change the Number of Digits . . . . . . . . . . . . . . . . . . . . . . . . 54

To Set the Integration Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

To Make Null (Relative) Measurements . . . . . . . . . . . . . . . . . . . . . . . . . 56

To Store Minimum and Maximum Readings (Stats) . . . . . . . . . . . . . . . 57

To Trigger the Meter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

To Use Reading Hold . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

To Make Voltage Ratio and Difference Measurements . . . . . . . . . . . . . 61

To Use Reading Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

3 Features and Functions

Features and Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66

General Measurement Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . 68

Input Filters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68

Integration Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

Reducing Measurement Noise . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

Number of Digits Displayed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

Ranging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

Overload Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

Voltage Measurement Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

Input Channels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

Resistance Measurement Configuration . . . . . . . . . . . . . . . . . . . . . . . . 81

Temperature Measurement Configuration . . . . . . . . . . . . . . . . . . . . . . 84

Measurement Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84

RTD Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85

Thermistor Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85

Thermocouple Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

Math Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87

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Null (Relative) Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .90

Reading Hold . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .92

Triggering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .93

Trigger Source Choices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .95

The Wait-for-Trigger State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .98

Halting a Measurement in Progress . . . . . . . . . . . . . . . . . . . . . . . . .98

Number of Samples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .99

Number of Triggers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .99

Trigger Delay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .100

Automatic Trigger Delays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .102

System-Related Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .103

Reading Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .103

Error Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .104

Self-Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .105

Display Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .106

Comma Separators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .107

Firmware Revision Query . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .107

SCPI Language Version . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .108

Voltmeter Complete Terminal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .109

External Trigger Terminal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .110

Chart Output (Analog Output) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .111

Chart Rollover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .113

Remote Interface Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .115

Remote Interface Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .115

GPIB Address . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .116

Baud Rate Selection (RS-232) . . . . . . . . . . . . . . . . . . . . . . . . . . . .117

Parity Selection (RS-232) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .118

Programming Language Selection . . . . . . . . . . . . . . . . . . . . . . . . .119

Connection to a Terminal or Printer (RS-232) . . . . . . . . . . . . . . . .120

Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121

Calibration Security . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .121

Calibration Count . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .124

Calibration Message . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .125

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Defaults, Power-On and Reset States . . . . . . . . . . . . . . . . . . . . . . . . . 126

4 Remote Interface Reference

Remote Interface Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131

Command Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133

Simplified Programming Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . 142

Using the MEASure? Command . . . . . . . . . . . . . . . . . . . . . . . . . . . 144

Using the CONFigure Command . . . . . . . . . . . . . . . . . . . . . . . . . . 144

Using the range and resolution Parameters . . . . . . . . . . . . . . . . . . 144

Using the READ? Command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145

Using the INITiate and FETCh? Commands . . . . . . . . . . . . . . . . . . 146

The MEASure? and CONFigure Commands . . . . . . . . . . . . . . . . . . . . 149

Setting the Function, Range, and Resolution . . . . . . . . . . . . . . . . . . . 152

Selecting the Input Channel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155

Special Resistance Measurement Commands . . . . . . . . . . . . . . . . . . 156

Temperature Measurement Commands . . . . . . . . . . . . . . . . . . . . . . . 157

Null (Relative) Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 160

Input Filter Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 162

Math Operation Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 164

Statistics operation commands (AVERage) . . . . . . . . . . . . . . . . . . 165

Scale operation commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166

Triggering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167

The Wait-for-Trigger State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169

Triggering Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170

Chart Output (Analog Out) Commands . . . . . . . . . . . . . . . . . . . . . . . . 172

System-Related Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173

The SCPI Status Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175

What is an Event Register? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175

What is an Enable Register? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175

What is a Condition Register? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176

SCPI Status System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177

The Status Byte . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178

14 Keysight 34420A User’s Guide

Page 19

Using Service Request (SRQ) and Serial POLL . . . . . . . . . . . . . . . .179

Using *STB? to Read the Status Byte . . . . . . . . . . . . . . . . . . . . . . .180

To Interrupt Your Bus Controller Using SRQ . . . . . . . . . . . . . . . . . .180

To Determine When a Command Sequence is Completed . . . . . .180

How to Use the Message Available Bit (MAV) . . . . . . . . . . . . . . . .181

Using *OPC to Signal When Data is in the Output Buffer . . . . . . .181

The Standard Event Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .182

The Questionable Data Register . . . . . . . . . . . . . . . . . . . . . . . . . . .183

The Operational Status and Condition Registers . . . . . . . . . . . . . .184

Status Reporting Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .186

Calibration Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .189

RS-232 Interface Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .191

RS-232 Configuration Overview . . . . . . . . . . . . . . . . . . . . . . . . . . .191

RS-232 Data Frame Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .192

Connection to a Computer or Terminal . . . . . . . . . . . . . . . . . . . . . .192

Connection to a Printer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .194

DTR / DSR Handshake Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . .194

RS-232 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .195

RS-232 Interface Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .197

An Introduction to the SCPI Language . . . . . . . . . . . . . . . . . . . . . . . .198

SCPI Data Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .200

Input Message Terminators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .201

Output Data Formats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .202

Using Device Clear to Halt Measurements . . . . . . . . . . . . . . . . . . . . .203

TALK ONLY for Printers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .204

To Set the GPIB Address . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .205

To Select the Remote Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .207

To Set the Baud Rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .209

To Set the Parity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .211

To Select the Programming Language . . . . . . . . . . . . . . . . . . . . . . . .213

Alternate Programming Language Compatibility . . . . . . . . . . . . . . . .215

Specific Issues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .215

Keysight 34420A User’s Guide 15

Page 20

SCPI Compliance Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 216

IEEE-488 Compliance Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . 219

5 Error Messages

Error Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 222

Execution Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 223

Self-Test Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 230

Calibration Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 232

6 Application Programs

Application Programs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 236

HP BASIC Language Programs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 237

HP BASIC/GPIB Program Example 1 . . . . . . . . . . . . . . . . . . . . . . . 237

HP BASIC/GPIB Program Example 2 . . . . . . . . . . . . . . . . . . . . . . . 238

HP BASIC/GPIB Program Example 3 . . . . . . . . . . . . . . . . . . . . . . . 240

HP BASIC/GPIB Program Example 4 . . . . . . . . . . . . . . . . . . . . . . . 243

RS-232 Operations with QuickBASIC . . . . . . . . . . . . . . . . . . . . . . . . . 245

Microsoft Visual Basic Language Program . . . . . . . . . . . . . . . . . . . . . 247

C Language Programs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 254

Compiling and Linking a C Program . . . . . . . . . . . . . . . . . . . . . . . . 254

C/GPIB Example 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 256

C/GPIB Example 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 258

C/GPIB Program Example 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 262

Microsoft Excel Macro Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 266

Macro Comments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 267

7Measurement Tutorial

Measurement Tutorial . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 272

Measurement Techniques and Sources of Error . . . . . . . . . . . . . . . . . 273

Voltage Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 273

Resistance Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 283

Temperature Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 288

Cleaning the Connector Contacts . . . . . . . . . . . . . . . . . . . . . . . . . . . . 297

16 Keysight 34420A User’s Guide

Page 21

Input Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .299

Obtaining Parts For the Input Connector . . . . . . . . . . . . . . . . . . . . . . .300

8 Specifications

Keysight 34420A User’s Guide 17

Page 22

THIS PAGE HAS BEEN INTENTIONALLY LEFT BLANK.

18 Keysight 34420A User’s Guide

Page 23

Keysight 34420A Nano Volt/Micro Ohm Meter User’s Guide

1 Quick Start

Quick Start 20 To Prepare the Meter For Use 21 If the Meter Does Not Turn On 22 To Adjust the Carrying Handle 24 To Make Input Connections 25 To Measure Voltage 27 To Measure Temperature With Thermistors 28 To Measure Temperature With RTDs 29 To Measure Temperature With Thermocouples 30 To Select a Range 31 To Set the Number of Digits 32 To Set the Integration Time 33 Front-Panel Display Formats 34 To Rack Mount the Meter 35

Page 24

1 Quick Start

Shift

DCV

Shift

NOTE

Quick Start

This chapter helps you prepare the meter for use and contains exercises designed to get you started with the meter, its menus, and the front panel.

The front panel has two rows of keys to select various functions and operations. Most keys have a shifted function printed in blue above the key. To perform a

shifted function, press (the Shift display annunciator will turn on). Then, press the key that has the desired label above it. For example, to select the

temperature measurement function, press .

If you accidentally press , just press it again to turn off the Shift annunciator.

The rear cover of this book is a fold-out Quick Reference Guide. On this cover you will find a quick summary of various meter features. Inside the rear cover is a diagram of the front panel menu options.

20 Keysight 34420A User’s Guide

Page 25

To Prepare the Meter For Use

Shift

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

1 Check the list of supplied items.

Verify that you have received the following items with your meter. If any item is missing, contact your nearestKeysight Technologies Sales Office.

– One low thermal input cable.

– One low thermal four-wire shorting plug.

– One power cord.

–This User’s Guide.

–One Service Guide.

–One folded Quick Reference card.

– Certificate of Calibration with removeable calibration label.

– One bottle of DeoxIT™ contact cleaner.

2 Connect the power cord and turn the meter on.

The front panel display will light up while the meter performs its power-on self-test. The GPIB bus address is displayed. The meter is left in 61/2 digit resolution, channel 1 input, and digital filter on.

Quick Start 1

[1]

To view the display with all annunciators turned on, hold down as you turn on the meter.

3 Perform a complete self-test.

The complete self-test performs a more extensive series of tests than those performed at power-on. Hold down Shift as you press the power switch to turn

on the meter; continue to hold for more than 5 seconds. The self-test will begin when you release the key.

If the self-test is successful, “PASS” is displayed on the front panel. If the test is not successful, “FAIL” is displayed and the ERROR annunciator turns on. See the Service Guide for instructions on returning the meter to Keysight Technologies for service.

[1] DeoxIT™ is a trademark of CAIG Laboratories, Inc., San Diego, California.

Keysight 34420A User’s Guide 21

Page 26

1 Quick Start

NOTE

If the Meter Does Not Turn On

Use the following steps to help solve problems you might experience when turning on the meter. If you need more help, see the Service Guide for instructions on returning the meter to Keysight Technologies for service.

1 Verify there is ac power to the meter.

First verify that the meter’s power switch is in the “On” position. Make sure the

power cord is firmly plugged into the power module on the meter’s rear panel.

Verify that the power source is energized.

2 Verify the power-line voltage setting.

The line voltage is set to the proper value for your country when the meter is

shipped from the factory. Change the voltage setting if it is not correct. The

settings are: 100, 120, 220, or 240 Vac (for 230 Vac operation, use the 220 Vac

setting).

See the diagram on the next page to verify or change the setting.

To replace the 250 mAT 250 V fuse, order part number 2110-0817. This fuse is used for all power line voltage settings.

22 Keysight 34420A User’s Guide

Page 27

Quick Start 1

1 Remove the power cord. Remove

the fuse holder assembly from the rear

3 Rotate the line-voltage selector

until the correct voltage appears in the window.

2 Install the fuse. Remove the

line-voltage selector from the assembly.

4 Replace the fuse-holder assembly

in the rear panel.

Install the correct fuse and verify that the correct line voltage appears in the window.

Keysight 34420A User’s Guide 23

Page 28

1 Quick Start

To Adjust the Carrying Handle

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

Bench-top viewing positions Carrying Position

24 Keysight 34420A User’s Guide

Page 29

To Make Input Connections

NOTE

WARNING

Using the Cable Provided

Align the front panel connector and cable conductors, press in.Tighten coupling nut.

Quick Start 1

Keysight 34420A User’s Guide 25

The connector and cable are an integral part of the measurement system. For the highest accuracy, use the copper cable and connectors supplied by Keysight Technologies.

The conductors may require occasional cleaning to remove oxides. Cleaning the conductors is described on page 297.

The connector body and cable shield are connected to earth ground.

Page 30

1 Quick Start

Using a Custom Cable

Refer to page 299 for additional information about building custom input cables.

26 Keysight 34420A User’s Guide

Page 31

To Measure Voltage

NOTE

Channel 1 Ranges: 1 mV, 10 mV, 100 mV, 1 V, 10 V, 100 V Maximum resolution: 0.1 nV (on 1 mV range)

Channel 2 Ranges: 1 mV, 10 mV, 100 mV, 1 V, 10 V Maximum resolution: 0.1 nV (on 1 mV range)

Independent NULL for each channel

Channel 1 LO to Channel 2 LO isolated to 150 Vpeak.

Quick Start 1

Scan mode alternates between input channels every 3 seconds or every measurement, whichever is longer.

Keysight 34420A User’s Guide 27

Page 32

1 Quick Start

To Measure Temperature With Thermistors

Thermistor type: 5 kW

28 Keysight 34420A User’s Guide

Page 33

To Measure Temperature With RTDs

4-wire, type: a = .00385 (DIN/IEC 751) or a = .00391

= 4.9 W to 2.1 kW

Quick Start 1

Keysight 34420A User’s Guide 29

Page 34

1 Quick Start

NOTE

To Measure Temperature With Thermocouples

Thermocouple types: B, E, J, K, N, R, S, T

Reference: external thermistor, external fixed value, or internal thermistor. Channel 2 only.

When using the internal thermistor as the temperature reference, you should make a custom cable to connect the thermocouple wire directly to the input terminals (see page 299).

30 Keysight 34420A User’s Guide

Page 35

To Select a Range

NOTE

You can let the meter automatically select the range using autoranging or you can select a fixed range using manual ranging.

Quick Start 1

– Autoranging is selected at power-on and after a remote interface reset.

– Autorange thresholds:

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 meter will

give an overload indication (“OVLD”).

– When making difference or ratio measurements, an overload on either channel

will give an overload indication (“OVLD”).

For voltage measurements, ranging is local to the selected channel. This means that you can select the ranging method (auto or manual) for each channel independently. When manually ranging, the selected range is local to the active channel; the meter remembers the range when you switch between channels.

Keysight 34420A User’s Guide 31

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1 Quick Start

To Set the Number of Digits

You can set the display to show 4½, 5½, 6½, or 7½ digits. In this book, the most significant digit (leftmost on the display) is referred to as the “½” digit, since it can only be a “0” or “1”. The number of digits displayed also depends upon the

integration time set, see page 33.

– The number of digits is set to 6½ digits at power-on and after a remote

interface reset.

– The number of digits shown is dependent upon integration time and filter

settings. The meter will not allow you to show more digits than the practical

measurement capability of the meter. You can, however, reduce the number of

digits shown.

32 Keysight 34420A User’s Guide

Page 37

To Set the Integration Time

NOTE

Integration time is specified in Number of Power Line Cycles (NPLC). You can set the NPLC to 0.02, 0.2, 1, 2, 10, 20, 100, or 200.

– You can set the integration time to one of three fixed values by choosing the

number of digits displayed, see page 32.

– You can set the integration time in the MEASure menu using the INTEGRATE

command.

– The Integration Time is directly related to the maximum number of digits the

meter will display.

Quick Start 1

NPLC

0.02 4½ 5½

0.2 5½ 6½

16½ 7½

26½ 7½

10 6½ 7½

20 7½ 7½

100 7½ 7½

200 7½ 7½

Filter Off

Max Digits Shown

Filter On

Max Digits Shown

– You can always show fewer digits than the maximum allowed (the minimum

number of digits shown is 4½).

Integration Time is local to the selected function. This means that you can select the integration time for each function independently. The meter remembers integration time when you switch between functions.

Keysight 34420A User’s Guide 33

Page 38

1.021,651 V

-045.230 mV

0.133,256,7 W

O.VLD mV

-H.DDD,DDD,D EFF

6 digits

“½” digit

5 digits

“½” digit

7 digits

“½” digit

Front-panel display format

This is the 1 V range,

This is the 100 mV range,

This is the 1 ohm range,

This is an overload indication on the 1 mV range.

6½ digits are displayed.

5½ digits are displayed.

7½ digits are displayed.

– H D E F

Negative sign or blank (positive) “½” digit (0 or 1) Numeric Digits Exponent (m, k, M) Measurement units

1 Quick Start

Front-Panel Display Formats

34 Keysight 34420A User’s Guide

Page 39

To Rack Mount the Meter

You can mount the meter in a standard 19-inch rack cabinet using one of three optional kits available. Instructions and mounting hardware are included with each rack-mounting kit. Any System II instrument of the same size can be rack-mounted beside the 34420A meter.

Remove the carrying handle, and the front and rear rubber bumpers, before rack-mounting the meter.

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

Quick Start 1

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

Keysight 34420A User’s Guide 35

Page 40

1 Quick Start

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).

36 Keysight 34420A User’s Guide

Page 41

Keysight 34420A Nano Volt/Micro Ohm Meter User’s Guide

2 Front-Panel Operation

Front-Panel Operation 38 Front-Panel Menu Reference 39 A Front-Panel Menu Tutorial 43 To Select an Input Channel 52 To Select a Range 53 To Set or Change the Number of Digits 54 To Set the Integration Time 55 To Make Null (Relative) Measurements 56 To Store Minimum and Maximum Readings (Stats) 57 To Trigger the Meter 59 To Use Reading Hold 60 To Make Voltage Ratio and Difference Measurements 61 To Use Reading Memory 62

Page 42

2 Front-Panel Operation

Front-Panel Operation

This chapter assumes you are familiar with the meter and menu operations. You should also understand how to make connections for the various types of measurements. If you are not familiar with this information, please read Chapter 1,

"Quick Start" starting on page 19.

This chapter does not give a detailed description of every front-panel key or menu operation. It does, however, give you a good overview of the front-panel menu and the most common front-panel operations. See Chapter 3, "Features and

Functions" starting on page 65, for a complete discussion of the meter’s

capabilities and operation.

38 Keysight 34420A User’s Guide

Page 43

Front-Panel Menu Reference

A: MEASurement MENU

1: DIG FILTER ) 2: INTEGRATE ) 3: OCOMP W ) 4: LOW POWER W ) 5: LOW VOLT W )

6: LoV LIMIT W

1: DIG FILTER Selects the digital filter speed. Can be set to FAST,

MEDIUM, or SLOW.

2: INTEGRATE Sets the measurement integration time.

3: OCOMP W Enables or disables offset compensation for resistance

measurements.

4: LOW POWER W Enables or disables low power ohms measurements.

5: LOW VOLT W Enables or disables voltage limited resistance

measurements.

6: LoV LIMIT W Sets the voltage limit for voltage limited resistance

measurements.

Front-Panel Operation 2

B: TEMPerature MENU

1:PROBE TYPE ) 2: UNITS ) 3: RTD TYPE ) 4:RTD Ro ) 5:T/C TYPE ) 6: COLD JUNCT ) 7:JUNCT

1: PROBE TYPE Selects thermocouples, thermistors, or RTDs as the

temperature probe.

2: UNITS Sets the measurement units to either °C, °F, or Kelvins.

3: RTD TYPE Sets the type of RTD in use.

4: RTD Ro Sets the nominal (0°C) value for the RTD in use.

5: T/C TYPE Selects the type of thermocouple in use.

6: COLD JUNCT Sets the source of the temperature reference junction.

7: JUNCT TEMP Allows direct entry of reference junction temperature.

Keysight 34420A User’s Guide 39

Page 44

2 Front-Panel Operation

C: MATH MENU

1: STATS ) 2: NULL VALUE ) 3: SCALE GAIN ) 4 : SCALE OFST

1:STATS Recalls the values of minimum, maximum, standard

2: NULL VALUE Selects independent null settings for voltage on channels 1

3: SCALE GAIN Sets the gain for linear scaling of the data.

4: SCALE OFST Sets the offset for linear scaling of data.

D: TRIGger MENU

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

1: READ HOLD Selects the reading hold sensitivity band.

2: TRIG DELAY Specifies a time delay between the trigger and the start of

3: N SAMPLES Sets the number of samples taken per trigger.

deviation, average, peak-to-peak, and number of readings.

and 2, resistance, and temperature functions.

the measurement.

40 Keysight 34420A User’s Guide

Page 45

Front-Panel Operation 2

E: SYStem MENU

1: RDGS STORE ) 2: SAVED RDGS ) 3: ERROR ) 4: TEST ) 5: CHART OUT ) 6: CHART SPAN )

7: CHART NULL ) 8: DISPLAY ) 9: COMMA ) 10: PRESET ) 11: REVISION

1: RDGS STORE Enables or disables reading memory.

2: SAVED RDGS Recalls readings stored in memory (up to 1024 readings).

3: ERROR Retrieves errors from the error queue (up to 20 errors).

4: TEST Performs a complete self-test or individual self-tests.

5: CHART OUT Enables or disables the chart recorder output (Analog Out).

6: CHART SPAN Sets the chart recorder output range (Analog Out).

7: CHART NULL S Sets the chart recorder output offset (Analog Out).

8: DISPLAY Enables or disables the front panel display.

9: COMMA Enables or disables a comma separator between digits in

the display.

10: PRESET Returns the meter to factory default settings.

11: REVISION Displays the meter’s firmware revision code.

F: Input / Output MENU

1: GPIB ADDR ) 2: INTERFACE ) 3: BAUD RATE ) 4: PARITY ) 5: LANGUAGE

1: GPIBADDR Sets the GPIB bus address (0 to 30, default 22).

2: INTERFACE Selects either the GPIB or RS-232 remote interface.

3: BAUD RATE Sets the baud rate for RS-232 operation.

4: PARITY Selects even, odd, or no parity for RS-232 operation.

5: LANGUAGE Selects interface language, either SCPI or Keithley 181.

Keysight 34420A User’s Guide 41

Page 46

2 Front-Panel Operation

G: CALibration MENU

1: SECURED ) [1: UNSECURED] ) [2:CALIBRATE] ) [3: CHART ZERO] ) [4 : CHART GAIN] )

[5: INJECTED I] ) 6:CAL COUNT ) 7:MESSAGE

[1]

1: SECURED The meter is secured against calibration; enter code to

unsecure.

1: UNSECURED The meter is unsecured for calibration; enter code to

secure.

2: CALIBRATE Performs a calibration of meter; must be UNSECURED.

3: CHART ZERO Performs a calibration of the chart recorder output zero

level.

4: CHART GAIN Performs a calibration of the chart recorder output gain.

5: INJECTED I Performs a calibration to minimize the injected current.

6: CAL COUNT Reads the total number of times the meter has been

calibrated.

7: MESSAGE Reads the first 11 characters of a calibration string, if any,

entered from the remote interface.

[1] The commands enclosed in square brackets ( [ ] ) are “hidden” unless the meter is UNSECURED for

calibration.

42 Keysight 34420A User’s Guide

Page 47

A Front-Panel Menu Tutorial

∧

∧ ∧

∧

Shift

∧

Shift∧Auto/Man

Shift

∧

NOTE

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 view by moving left or right .

Front-Panel Operation 2

–To turn on the menu, press

–To turn off the menu, press

(Menu On/Off).

(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 .

–To recall the last menu command that was executed, press

(Menu

Recall).

–To turn off the menu at any time without saving changes, press any function

key

If you become confused or get lost at any point during the tutorial, simply turn off the menu and start over again with step 1 for that example.

Keysight 34420A User’s Guide 43

Page 48

2 Front-Panel Operation

∧

∧ ∧

∧∧∧∧∧

∧

Shift∧∧

Auto/Man

Shift

∧

Auto/Man

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 Shift (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 view the choices.

COMMANDS - You are on the commands level. Press or to view the command choices

within the selected menu group.

PARAMETER - You are on the parameter level. Press or to view and edit the parameter for the selected command.

MENU BOTTOM - You pressed while on the parameter level; this is the bottom level of the menu and you cannot go any lower.

To turn off the menu, press (Menu On/Off). To move up a level, press .

ENTERED - The change made on the parameter level is saved. This is displayed after you press Auto/ Man (Menu Enter) to execute the command.

MIN VALUE - The value you specified 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 maximum value allowed is displayed for you to edit.

EXITING - 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 on the parameter level and changes were NOT saved.

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 parameters but the changes were

NOT saved. Press

VOLTS ONLY - The requested function is only available for voltage measurements. UNAVAILABLE - The action requested is NOT allowed in the present configuration.

(Menu Enter) to save changes made on the parameter level.

44 Keysight 34420A User’s Guide

Page 49

Front-Panel Operation 2

-0.824,153 V -0.824153 V

With comma separator

(factory setting)

Without comma separator

Shift

∧

On/Off

A: MEAS MENU

∧∧∧

∧

E: SYS MENU

Menu Example 1

The following steps show you how to turn on the menu, move 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 display comma separator.

The meter can display readings on the front panel with or without a comma separator. The following steps show how to disable the comma.

1 Turn on the menu.

You enter the menu on the menus level. The MEAS MENU is your first choice on this level.

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

There are six menu group choices available on the menus level. Each choice has a letter prefix for easy identification (A: , B: , etc.).

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2 Front-Panel Operation

∧

1: RDGS STORE

∧∧∧∧∧∧∧

∧

9: COMMA

∧

ON∧OFF

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

The RDGS STORE command is your first choice on this level.

4 Move across to the COMMA command on the command s level.

There are eleven command choices available in the SYS MENU. Each choice on

this level has a number prefix for easy identification (1: , 2: , etc.).

5 Move down a level to the COMMA parameter choices.

The first parameter choice is ON for the COMMA command (the comma

setting is stored in non-volatile memory and ON is the factory setting).

6 Move across to the OFF choice.

There are two parameter choices for COMMA.

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Front-Panel Operation 2

Auto/Man

ENTER

ENTERED

Shift

∧

Recall

9: COMMA

∧

OFF

7 Save the change and turn off the menu.

The meter beeps and displays a message to show that the change is now in effect. You are then exited from the menu. The meter will no longer show commas in the display.

Menu Example 2

The following exercise demonstrates how to use the menu recall feature as a shortcut to set the COMMA command back to its original setting. You must

perform the steps in Menu Example 1 before you start this example.

1 Use menu recall to return to the COMMA command.

This returns you to the COMMA command, which was the last command used before you exited the menu in the Example 1.

2 Move down to the COMMA parameter choices.

The first parameter choice is OFF (the current setting from Example 1).

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2 Front-Panel Operation

∧

Auto/Man

ENTER

ENTERED

Shift

∧

On/Off

A: MEAS MENU

3 Move across to the ON choice.

Set the parameter back to its original value.

4 Save the change and turn off the menu.

The meter beeps and displays a message to show that the change is now in

effect. You are then exited from the menu.

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 for channel 1 to –30 millivolts.

Make sure the meter has channel 1 selected, is in the dc voltage function, and has 6½ digits displayed. Connect the four-wire short to the meter input.

1 Turn on the menu.

You enter the menu on the menus level. The MEAS MENU is your first choice

on this level.

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Front-Panel Operation 2

∧

C: MATH MENU

∧

1: STATS

∧

2: NULL VALUE

∧

0.000,000,0 V

∧

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

There are six menu group choices available on this level.

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

The STATS command is your first choice on this level.

4 Move across to the NULL VALUE command.

5 Move down to edit the NULL VALUE parameter.

The null value should be 0.000000 V when you come to this point in the menu for the first time. For this example, you will first set the null value to –0.300000 volts.

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 .

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2 Front-Panel Operation

∧∧– 0.000,000,0 V

∧

– 0.000,000,0 V

∧∧∧

– 0.300,000,0 V

∧∧∧∧∧∧∧

– 0.300,000,0 V

6 Make the number negative.

The left most character on the display toggles between +, –, and

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

Notice that the digit to the right of the decimal point is flashing.

8 Increment the digit until “3” is displayed.

You decrement or increment each digit independently. Neighboring digits are

not affected.

9 Move the flashing cursor over to the units location.

50 Keysight 34420A User’s Guide

Notice that the units are flashing on the right side of the display.

Page 55

Front-Panel Operation 2

∧

– 030.000,00 mV

Auto/Man

ENTER

ENTERED

Null

Shift

∧

NOTE

10 Decrease 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 and the mV annunciator is on.

11 Save the change and turn off the menu.

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

You will be returned to the normal measurement display, and, if you have installed the four-wire short, the display will show a positive measurement in the approximate amount of the null value just entered.

The Null annunciator is on in the display.

Keep in mind that null is turned on and - 0.03 volts is used as the null value for measurements. To clear the null value, press .

Hint You can use the menu recall feature to save steps when entering the null

value. First, press on the front panel and then press

(Menu

Recall). The meter will jump to the 2: NULL VALUE command. Press . The null value in the display is the first reading taken after you turned NULL on. You can then edit this number as described.

This is the end of the front-panel menu tutorial. The remainder of the chapter discusses several of the most common front-panel operations.

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2 Front-Panel Operation

Channel

Shift

Channel

NOTE

To Select an Input Channel

For voltage measurements, you have two independent input channels.

–Pressing toggles the display between Channel 1 and Channel 2.

– Pressing (Scan) creates an alternating Channel 1 and Channel 2

display. Press again to cancel.

Scan mode alternates between input channels every 3 seconds or every measurement, whichever is longer. If you are using the scan mode, turn off all the input filters (both digital and analog), see page 68.

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To Select a Range

NOTE

You can let the meter automatically select the range using autoranging or you can select a fixed range using manual ranging.

Front-Panel Operation 2

– Autoranging is selected at power-on and after a remote interface reset.

– Autorange thresholds:

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 meter will

give an overload indication (“OVLD”).

– When making difference or ratio measurements, an overload on either channel

will give an overload indication (“OVLD”).

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2 Front-Panel Operation

To Set or Change the Number of Digits

integration time set, see page 55.

– The number of digits is set to 6½ digits at power-on and after a remote

interface reset.

– The number of digits shown is dependent upon integration time and filter

settings. The meter will not allow you to show more digits than the practical

measurement capability of the meter. You can, however, reduce the number of

digits shown.

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To Set the Integration Time

NOTE

Integration time is specified in Number of Power Line Cycles (NPLC). You can set the NPLC to 0.02, 0.2, 1, 2, 10, 20, 100, or 200.

– You can set the integration time to one of three fixed values by choosing the

number of digits displayed, see page 54.

– You can set the integration time in the MEASure menu using the INTEGRATE

command.

– The Integration Time is directly related to the maximum number of digits the

meter will display.

Front-Panel Operation 2

NPLC

0.02 4½ 5½

0.2 5½ 6½

16½ 7½

26½ 7½

10 6½ 7½

20 7½ 7½

100 7½ 7½

200 7½ 7½

Filter Off

Max Digits Shown

Filter On

Max Digits Shown

– You can always show fewer digits than the maximum allowed (the minimum

number of digits shown is 4½).

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2 Front-Panel Operation

Null

Shift

∧

To Make Null (Relative) Measurements

Each null measurement, also called relative, is the difference between a stored null value and the input signal. See page 90.

Read ing = measurement – null value

– You can make null measurements on any function or channel. You can set a

null for each channel and function independently. The meter remembers the

null value when you switch between input channels or functions.

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

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

– The first reading taken after you press 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

(Menu Recall). This takes you to the “NULL VALUE” command in the MATH

MENU (only if null is enabled). Go down to the “parameter” level, and then edit

the displayed value.

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Front-Panel Operation 2

Shift

∧

∧ ∧

∧

Shift

∧

To Store Minimum and Maximum Readings (Stats)

You can store the minimum and maximum readings during a series of measurements. The following discussion shows how to read the minimum, maximum, average, peak-to-peak, standard deviation, and reading count.

– You can use stats with any function. When you change functions, stats

operation is disabled.

– Changing input channels or selecting Scan does not disable stats. The stored

readings, however, are not marked as to the input channel.

– After enabling stats, you can read the stored minimum, maximum, average,

standard deviation, peak-to-peak, and count by pressing

(Menu

Recall). This takes you to the “STATS” command in the MATH MENU (only if stats is enabled). Go down to the “parameter” level , and then read the

values by pressing or .

– After reading the stored value, pressing

(Menu On/Off) returns to

the measurement display and continues stats operations.

– The stored values are cleared when you turn stats on, turn off the power, or

perform either a remote interface reset or preset.

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2 Front-Panel Operation

– The average and standard deviation are of all readings taken since stats was

enabled (not just the average of the stored minimum and maximum). The

count is the total number of readings taken since stats was enabled.

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To Trigger the Meter

Single

You can trigger the meter from the front panel using single trigger or autotrigger.

Front-Panel Operation 2

– Autotriggering is enabled when you turn on the meter. Notice that the

* (sample) annunciator turns on during each measurement.

– Single triggering takes one reading each time you press and then waits

for the next trigger. Continue pressing this key to trigger the meter.

Using an External Trigger

The external trigger mode is also enabled by pressing . It is like the single trigger mode except that you apply a trigger pulse to the rear-panel Ext Trig terminal. The meter is triggered on the negative edge of a TTL pulse.

The front-panel key is disabled when in remote.

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2 Front-Panel Operation

Shift

∧

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 meter emits a beep and holds the value on the display.

– Reading hold has an adjustable sensitivity band to allow you to select which

readings are considered stable enough to be displayed. The band is expressed

as a percent of reading on the selected range. The meter will capture and

display a new value only after three consecutive readings are within the band.

– The default band is 0.10% of reading. After enabling reading hold, you can

choose a different band by pressing

the “READ HOLD” command in the TRIG MENU (only if reading hold is

enabled).

Go down to the “parameter” level, and then select a value: 0.01%, 0.10%,

1.00%, or 10.00% of reading.

– The sensitivity band is stored in volatile memory; the meter sets the band to

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

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(Menu Recall). This takes you to

Page 65

Front-Panel Operation 2

Difference Ch 1 voltage Ch 1 Null–()Ch 2 voltage Ch 2 Null–()–()Null–=

Ratio

Ch 1 voltage Ch 1 Null–() Ch 2 voltage Ch 2 Null–()

---------------------------------------------------=

To Make Voltage Ratio and Difference Measurements

To calculate a voltage ratio, the meter measures the voltages applied to the Channel 1 input terminals and Channel 2 input terminals. The calculation is as follows:

[1]

– Maximum input signal on Channel 1 is 120 Vdc, the meter will autorange on

the actual input or can be manually set.

– Maximum input signal on Channel 2 is 12 Vdc, the meter will autorange on the

actual input or can be manually set.

– Maximum voltage difference between Channel 1 LO and Channel 2 LO is 150

Vdc.

– Null, if used, is independent for each channel. An additional null

[1]

of the difference can also be made. If null is used on either input channel, the ‘Null’ annunciator will flash when the difference function is selected. If you null the difference, the ‘Null’ annunciator will be steady.

[1] The difference null is only available from the front panel.

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2 Front-Panel Operation

Single

Shift

∧

On/Off

A: MEAS MENU

∧∧∧

B: SYS MENU

∧

1: RDGS STORE

To Use Reading Memory

The meter can store up to 1024 readings in internal memory. The following steps demonstrate how to store readings and retrieve them.

1 Select the function.

Select any measurement function. You can change the function at any time during reading memory.

2 Select the single trigger mode.

Notice that the Trig annunciator turns on. When reading memory is enabled, readings are stored when you trigger the meter.

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

3 Turn on the menu.

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

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

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Front-Panel Operation 2

∧∧ON

Auto/Man

ENTER

Single

Shift

∧

Recall

2: SAVED RDGS

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

7 Save the change and exit the menu.

Notice that the Mem (memory) annunciator turns on to indicate that the meter is ready to store readings. Up to 1024 readings can be stored in first-in-first-out (FIFO) order. When memory is full, the Mem annunciator will turn off.

Readings are preserved until you re-enable reading memory at another time, turn off the power, or perform a remote interface reset.

8 Trigger the meter three times.

This stores three readings in memory.

9 Use menu recall to retrieve the stored readings.

This takes you to the “SAVED RDGS” command in the SYS MENU.

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 reading displayed is the first reading that was stored (FIFO). If no readings are stored in memory, “EMPTY” is displayed. The first five digits of the reading and the reading number are displayed. After a brief pause, the reading number is removed and all reading digits are shown. The stored readings are displayed with their units (m, m, k, etc.) when appropriate. For example:

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2 Front-Panel Operation

10.31607K: 11

10.316076 K

Reading

number

Units

∧

Shift

∧

On/Off

EXITING

11 Move across to view the two remaining stored readings.

The readings are stored horizontally on the “parameter” level.

If you press when you first 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.

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Keysight 34420A Nano Volt/Micro Ohm Meter User’s Guide

3 Features and Functions

Features and Functions 66 General Measurement Configuration 68 Voltage Measurement Configuration 78 Resistance Measurement Configuration 81 Temperature Measurement Configuration 84 Math Operations 87 Null (Relative) Operation 90 Reading Hold 92 Triggering 93 System-Related Operations 103 Voltmeter Complete Terminal 109 External Trigger Terminal 110 Chart Output (Analog Output) 111 Remote Interface Configuration 115 Calibration 121 Defaults, Power-On and Reset States 126

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3 Features and Functions

Features and Functions

You will find that this chapter makes it easy to look up all the details about a particular feature of the meter. Whether you are operating the meter from the front panel or from the remote interface, this chapter will be useful.

This chapter is divided into the following sections:

– “General Measurement Configuration” on page 68

– “Voltage Measurement Configuration” on page 78

– “Resistance Measurement Configuration” on page 81

– “Temperature Measurement Configuration” on page 84

– “Math Operations” on page 87

– “Null (Relative) Operation” on page 90

– “Reading Hold” on page 92

– “Triggering” on page 93

– “System-Related Operations” on page 103

– “Voltmeter Complete Terminal” on page 109

– “External Trigger Terminal” on page 110

– “Chart Output (Analog Output)” on page 111

– “Remote Interface Configuration” on page 115

– “Calibration” on page 121

– “Defaults, Power-On and Reset States” on page 126

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 Operation" starting on page 37, you may want to read it now. Chapter 4, "Remote Interface

Reference" starting on page 129, lists the syntax for the SCPI (Standard

Commands for Programmable Instruments) commands available to program the meter.

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Features and Functions 3

NOTE

Throughout this manual, the following conventions are used for SCPI command syntax. Square brackets ( [] ) indicate optional keywords or parameters. Braces ( {} ) enclose a list of parameters separated with a vertical bar (|), use only one of the values . Triangle brackets ( <> ) indicate that you must substitute a value for the enclosed parameter.

The actual command string you send to the meter should not include any of the conventions indicated above.

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3 Features and Functions

General Measurement Configuration

This section contains information to help you configure the meter for making measurements. You may never have to change any of the measurement parameters discussed here, yet they are provided to give you the flexibility you might need.

Input Filters

Two input filters are available; a digital filter and an analog filter. You can enable the digital filter, the analog filter, or both. The digital filter may be used for any measurement type. The analog filter is only available for thermocouple temperature measurements and voltage measurements on the 1 mV, 10 mV, or 100 mV ranges.

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Features and Functions 3

Shift

Filter

Enter

Filter

– Front Panel operation: Press and scroll to one of DIGITAL,

ANALOG, or ANA + DIG. Press to enable the filter type. Press the key to turn the filter on or off.

To set the digital filter averaging, use the MEASurement menu 1: DIG FILTER command.

– Remote operation: the following commands turn the filters off, on, set the

digital filter count:

INPut:FILTer

:STATe {OFF|ON} :TYPE {ANAlog|DIGital|BOTH} :DIGital:RESPonse {SLOW|MEDium|FAST} :DIGital:PRECharge {ON|OFF}

Using the filters in remote operation is not recommended. Use:

INPut:FILTer:STATe OFF

to disable the filters. The digital filter is also disabled following a remote reset (*RST) or preset (SYStem:PREset).

Use the math operation (AVERage) commands to obtain a single reading that is the average of a number of readings (see page 164). An example program is shown on page 243 in Chapter 6.

If you attempt to use the digital filter in remote operations, be aware of the following special conditions:

The digital filter requires a number of readings to settle (10, 50 or 100). The digital filter readings only occur when the meter is triggered to take a reading. In remote operation a reading is only taken when requested. For example, if you have set the digital filter to MEDIUM (50 readings), you will need to request (trigger) 50 readings from the remote interface before the filter can settle. It is also possible that after 50 readings the digital filter will still not be settled as described in the next paragraph.

The STATus:OPERational:CONDition register contains a bit that indicates the settled/unsettled state of the digital filter on a per reading basis. See

page 184 in Chapter 4. You should check the state of this bit for each reading

to ensure the digital filter count has not reset (filter reset operation is described in the next section).

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3 Features and Functions

Digital Filter

– The digital filter is a moving average (boxcar) filter. Equal weighting is applied

to all readings to calculate the displayed reading.

– Three digital filters are available:

SLOW (average last 100 readings),

MEDIUM (average last 50 readings), or

FAST (average last 10 readings)

– When the digital filter is enabled, the ‘Filt’ annunciator flashes until the

required number of readings are obtained. The measurement displayed before the ‘Filt’ annunciator is steady is the average of the number of readings taken so far. For example, with the filter set to MEDIUM (average of 50 readings), the measurement displayed after 20 readings will be the average those 20 readings. The ‘Filt’ annunciator will flash until 50 readings have been taken.

– The filter count resets (and the ‘Filt’ annunciator will flash) if the function,

range, integration time, or channel is changed.

– The filter count resets if a reading is outside a set range of the average. The

amount of input reading change required to reset the filter count is:

1mV Range All Other Ranges

FAST ± 400 ppm of range ± 100 ppm of range

MEDIUM ± 700 ppm of range ± 300 ppm of range

SLOW ± 2000 ppm of range ± 1000 ppm of range

Analog Filter

The analog filter is an 11 Hz, two-pole low pass filter. Use this filter to remove line frequency noise from the input measurement.

– The filter requires approximately 300 milliseconds after the input is present to

settle. Using the filter, therefore, slows the measurement rate significantly.

– Use the analog filter only when line power noise (50/60 Hz) is causing an

overload (OVLD) condition. See page 77.

– The analog filter is available for voltage and thermocouple temperature

measurements. The analog filter is not available for resistance measurements.

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– The analog filter is available for the 1 mV, 10 mV, and 100 mV ranges.

Integration Time

Integration time is the period during which the meter’s analog-to-digital (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).

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

choices are 0.02, 0.2, 1, 2, 10, 20, 100, or 200 power line cycles. The default is 10 NPLCs.

– The integration time is stored in volatile memory; the meter selects 10 NPLC

when power has been off or after an interface reset.

– Only the integer number of power line cycles (1, 2, 10, 20, 100 or 200 NPLC)

provide normal mode (line frequency noise) rejection.

– Integration time is related to the maximum number of digits the meter will

display. You can always choose to show fewer digits than the maximum allowed (the minimum number of digits shown is 4½).

Features and Functions 3

NPLC

0.02 4½ 5½

0.2 5½ 6½

16½ 7½

26½ 7½

10 6½ 7½

20 7½ 7½

100 7½ 7½

200 7½ 7½

Digital Filter Off

Max Digits Shown

Digital Filter On

Max Digits Shown

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3 Features and Functions

NOTE

– Front Panel operation: Integration time can be set indirectly when you select

the number of digits (see page 54).

You can also set the integration time in the MEASurement menu with the 2: INTEGRATE command.

– Remote operation: Refer to the table on page 144. Use one of the following

commands:

[SENSe:]

VOLT:DC:NPLC {0.02|0.2|1|2|10|20|100|200|MIN|MAX} FRES|RES

TEMP:NPLC {0.02|0.2|1|2|10|20|100|200|MIN|MAX}

Integration time and resolution are related. The CONFigure and MEASure? commands can also set the integration time, see page 144.

Integration Time is local to the selected function. This means that you can select the integration time for each function independently. The meter remembers the integration time when you switch between functions.

:NPLC {0.02|0.2|1|2|10|20|100|200|MIN|MAX}

Reducing Measurement Noise

At high resolutions and low measurement levels, measurement noise can become an important factor in the accuracy of your measurements. One possible source of measurement noise is the wiring and cabling in the test setup. These noise sources and their effects are discussed in Chapter 7, "Measurement Tutorial". A smaller level of noise is also inherent in the meter itself.

To minimize the effects of noise on your measurements, use the highest possible integration time (NPLC) and average the readings. Faster reading rates are more susceptible to noise. Choosing the best NPLC and averaging method for your measurement requires a tradeoff between the reading rate and the level of acceptable noise in the resulting measurement.

The Integration Time (NPLC) and averaging can be multiplied to create an equivalent NPLC. The equivalent NPLC defines the reading rate and characterizes the expected noise level. Averaging can be performed in the meter by using either the digital filter or by using the statistics (Stats) mode of operation.

Measurement noise characteristics of the meter closely match theoretical gaussian noise distributions. The graph on the next page shows typical input

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Features and Functions 3

noise measurements for the 1 mV range with the low thermal shorting plug applied to the input terminals. Other functions and ranges will exhibit similar noise reduction characteristics versus NPLC.

For example, if you set the NPLC to 20 and enable the digital filter set to FAST (10 reading average), the equivalent NPLC is 200. At an equivalent NPLC of 200, the reading rate is approximately 6 readings per minute (digital filter fully settled) and the typical noise level expected is 1.6 nVrms.

Alternately, if you take readings every 5 minutes, you can set an equivalent NPLC of 5000 to minimize the noise in the measurement. An equivalent NPLC of 5000 could be obtained by setting the integration time to 100 NPLC and enabling the digital filter set to MEDIUM (50 reading average). At this equivalent NPLC, a typical noise level of 0.35 nVrms can be expected.

– Front Panel operation: Integration time can be set indirectly when you select

the number of digits (see page 54).

You can also set the integration time in the MEASurement menu with the 2: INTEGRATE command.

Enable the digital filter and set the filter reading average as described on

page 68.

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3 Features and Functions

– Remote operation: Set the integration time for the measurement function. If

possible, use NPLC 200. If you use the CONFigure or MEASure commands, refer to the table on page 144.

Use the math operations (AVERage) to average the readings or average the readings in your program. An example program that uses the math operations to average readings is shown on page 243 in Chapter 6. Do not use the digital

filter to average readings, see page 69.

Number of Digits Displayed

Front Panel operation only. See also “Integration Time” on page 71.

– You can set the number of digits shown in the display to 4, 5, 6, or 7 full digits,

plus a “½” digit which can only be a “0” or “1”.

– You can set both the number of digits displayed and the Integration Time in a

single operation by pressing digits keys (see page 54).

– You can change the number of digits displayed without disturbing the

Integration Time settings by pressing the < or > keys (see page 54).

– The number of digits is set to 6½ digits at power-on and after either a remote

interface reset or preset.

– The number of digits shown is dependent upon integration time and filter

settings. The meter will not allow you to show more digits than the practical measurement capability of the meter. You can, however, reduce the number of digits shown. The minimum number of digits available is 4½. (See the table on

page 71).

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Features and Functions 3

0.003,256,4 W

0.216,569 mV

–045.231 mV

7 digits

“½” digit

6 digits

“½” digit

5 digits

“½” digit

This is the 1 ohm range,

This is the 1 mV range,

This is the 100 mV range,

7½ digits are displayed.

6½ digits are displayed.

5½ digits are displayed.

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3 Features and Functions

∧∧Auto/Man

Ranging

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

– The selected mode (auto or manual range) is stored in volatile memory; the

meter returns to autoranging when power has been off or after a remote interface reset.

–Autorange thresholds:

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 meter

gives an overload indication: “OVLD” from the front panel or “9.90000000E+37” from the remote interface.

– For ratio and difference measurements, the specified range is independent for

both Channel 1 and Channel 2.

– Front Panel operation: Press a front-panel RANGE key to set manual ranging

and to up or down range. Press the Auto/Man key to return to autoranging.

See also “To Select a Range” on page 53.

– Remote operation: Range is set with parameters in the MEASure and

CONFigure subsystems. For example:

CONF:VOLT:DC 10.0 Sets the 10 Volt DC range

Range can be set directly with the SENSe subsystem. For example:

SENS:VOLT:DC:RANGe 0.001 Sets the 1 mV DC range

SENS:RES:RANGE:AUTO Sets auto ranging on 2-wire

resistance measurements

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Overload Detection

The 34420A uses both an analog and digital method to generate an overload condition and display the OVLD message. An understanding of the cause of the overload can help you make more accurate measurements.

Digital Overload Detection

The digital overload detect occurs when the magnitude of the measurement is greater than 120% of the Range. For example, on the 1 volt Range, signal levels of greater than ± 1.2 volts will cause an OVLD in the display.

Analog Overload Detection

Another type of overload can result in measurement errors that are hard to identify. For example if an overload signal only occurs for a portion of the measurement period, the input amplifier could become non-linear resulting in an inaccurate reading. The displayed result may appear to be correct because the overload signal only occurred during a small portion of the measurement cycle. The 34420A detects this problem by providing comparators on the input amplifier. If signals large enough to overload the input amplifier are detected, the display will read OVLD. The comparators detect signals greater than 140% of the range setting.

If an overload occurs, two solutions are possible.

– Setting the meter to the next higher range will provide 10 times improvement

in the overload signal handling capability. For example,if you are measuring on the 1 mV range and have 2 mV rms of power line (50 or 60 Hz) pickup, the noise overload comparators would sense the peaks of the signals and an OVLD message would be displayed. If you set the range to 10 mV, the resolution (with 7 digits) is still 1 nanovolt, and the reading rate is faster than if ANALOG FILTER had been turned on. Additionally, the 10 mV range noise is almost as low as the 1 mV range.

– Alternately, if using the 1 mV, 10 mV, or 100 mV ranges, turn on the ANALOG

FILTER. The reading rate slows down with the filter on. In the case of a larger overloads (for example, 20 mV rms noise on the 1 mV range) using the ANALOG FILTER would give a lower noise result than changing to the 100 mV range.

Features and Functions 3

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3 Features and Functions

Channel

Shift

Channel

Scan

Voltage Measurement Configuration

Input Channels

The meter has two independent input channels for measuring dc Volts. You can make measurements on either or both channels, measure the difference between the channels, or measure the ratio between the channels. Each channel has an independent settings for null and range.

The figure on page 27 shows connections for two input channels.

– Channel 1 is the default input channel. Both channels use the same

integration time setting.

– The maximum measurable input on Channel 1 is 120V, on Channel 2 is 12 V.

– For two channel operation, the maximum voltage difference between Channel

1 LO and Channel 2 LO is ±150 V.

– For either channel, the maximum non-destructive input is ±150 V.

– If you enable input filters, the filters are active for both input channels.

Switching between the channels will reset the digital filter reading count (see

page 70).

– Front Panel operation: Toggle the input channel by pressing the Channel key

on the front panel. The CH1 or CH2 annunciator will light in the display. The meter keeps range and null settings independently for each channel.

Choose the scan mode to alternately show the CH1 and CH2 readings. Disable the digital filter when using the scan mode. In scan mode, the meter alternates between the CH1 and CH2 readings every 3 seconds or for each measurement (whichever is longer).

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Features and Functions 3

Ch1 - Ch2

Difference Ch 1 voltage Ch 1 Null–()Ch 2 voltage Ch 2 Null–()–()Null–=

Shift

Ch1 - Ch2

Ratio

Ch 1 voltage Ch 1 Null–() Ch 2 voltage Ch 2 Null–()

---------------------------------------------------=

– Remote operation: The CONFigure and MEASure subsystems use an optional

parameter to specify the input channel as either 1 or 2:

CONF:VOLT:DC DEF, DEF,(@FRONTl) Channel 1 operation

CONF:VOLT:DC DEF, DEF,(@FRONT2) Channel 2 operation

The SENSe subsystem uses a keyword modification to indicate the channel:

SENS1:VOLT:DC:RANG:AUTO Channel 1 operation

SENS2:VOLT:DC:RANG:AUTO Channel 2 operation

Two Channel Measurements

– Difference measurements: First, set the range and null value for each input

channel. Then, select difference measurements.

[1]

– Ratio measurements: First, set the range and null value for each input

channel. Then, select ratio measurements.

– Remote operation: use the following commands to measure or configure a

difference or ratio measurement. Set each channel to the appropriate range and null conditions using:

[SENSe1:|SENSe2:]

VOLTage:DC

:RANGE <range> :NULL:STATe {OFF|ON} :NULL:VALue {<value>|MIN|MAX}

[1] The difference null is only available from the front panel.

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3 Features and Functions

Then use the following commands to measure the ratio or difference:

MEASure:VOLTage:DC + :RATIO?

:DIFFerence?

CONFigure:VOLTage:DC

:RATIO

:DIFFerence [SENSe:]FUNCtion "VOLTage:RATio" [SENSe:]FUNCtion "VOLTage:DIFFerence"

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Resistance Measurement Configuration

The meter can make 2-wire or 4-wire ohms measurements. The meter can compensate for voltages in the resistive circuit being measured using offset compensation. You can also choose to either limit the power applied or limit the open circuit voltage applied during a resistance measurement.

The test current sourced by the meter depends upon the range and conditions as shown below:

Range

1 W 10 mA 10 mA Not Available

10 W 10 mA 10 mA 1 mA

100 W 10 mA 1 mA 100 mA

1 kW 1 mA 100 mANot Available

10 kW 100 mA10 mANot Available

[a]

100 kW

[a]

1 MW

2-wire or 4-wire

measurements

10 mA5 mANot Available

5 mA5 mANot Available

Features and Functions 3

Test current

4-wire measurements

Low Power Voltage Limited

[a] Offset Compensation is not applied to measurements on these ranges

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3 Features and Functions

Offset Compensated Measurements

Offset compensation removes the effect of any voltages in the circuit being measured. The technique involves taking two measurements, one with the current source turned on, and one with the current source turned off and computing the difference. A description of this operation is given on page 284.

– Front Panel operation: Offset compensation is on at power on. Turn offset

compensation off under the 3: OCOMP W command in the MEASure menu.

– Remote operation: Offset compensation is off following a remote reset or

preset. Use the following command to change the state of offset compensation:

SENSe:

FRESistance:OCOMpensated {OFF|ON}

RESistance:OCOMpensated {OFF|ON}

Low Power Measurements

Low Power measurements use a reduced output measurement current to limit the power dissipation in the circuit being measured.

– Low Power measurements apply only to 4-wire ohms measurements.

– When the low power measurement mode is enabled, the ‘LP’ annunciator is on

in the display.

– Setting the Voltage Limited measurement mode will cancel the Low Power

mode.

– Front Panel operation: set low power mode under the 4: LOW POWER W

command in the MEASure menu.

– Remote operation: use the following command to set the low power ohms

mode:

SENSe:FRESistance:POWer:LIMit {OFF|ON}

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Features and Functions 3

Voltage Limited Measurements

Voltage limited resistance measurements clamp the open circuit voltage to predefined limits.

– Voltage limits apply only to 4-wire ohms measurements.

– Voltage limited resistance measurements are only available on the 10 W and

100 W ranges. If a manual range is selected in either 2-wire or 4-wire ohms, and then Voltage Limited measurements are enabled, the range will be set to the highest valid range (either 10 W or 100 W).

– The open circuit voltage can be limited to 20 mV, 100 mV, or 500 mV.

– Setting the Low Power measurement mode will cancel the Voltage Limited

mode.

– Front panel operation: Enable or disable the voltage limit under the 5: LOW

VOLT W command in the MEASure menu.

Set the voltage limit under the 6: LoV LIMIT W command in the MEASure menu.

– Remote operation: the following command enables or disable the low voltage

limit mode:

SENSe:FRESistance:VOLTage:LIMit {OFF|ON}

Set the limit with the following command:

SENSe:FRESistance:VOLTage:LIMit:VALue {<value>|MIN|MAX}

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3 Features and Functions

Temperature Measurement Configuration

This section contains information to help you configure the meter for making temperature measurements. To measure temperature, you will need a temperature transducer. Transducer descriptions and specific comments about their usage are given on page 288. The meter supports three general categories of transducer:

– RTD (Resistive Temperature Device)

– THERM (Thermistor)

– T/C (Thermocouple)

The meter supports specific types of transducers in each category:

RTD’s R0 = 4.9 W to 2.1 kW

a = 0.00385 (DIN/IEC 751) a = 0.00391

Once you set the measurement units, probe type, and transducer type, the setting is stored in non-volatile memory. This makes the last probe type used the default probe type.

Measurement Units

– The meter can report temperature in °C (Celsius), °F (Fahrenheit), or K

(Kelvins).

– The measurement units set are stored in non-volatile memory.

– Front Panel Operation: Set the units under the 2: UNITS command in the

TEMPerature menu.

– Remote operation: Set the units using the following command:

UNIT:TEMPerature {C|F|K}

Thermistor Thermocouples

5k W B, E, J, K, N, R, S, T

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RTD Measurements

– The meter supports RTDs with a = 0.00385 (DIN/IEC 751) or a = 0.00391. The

nominal value of the RTD (R

Connections are shown on page 29.

– The meter makes a 4-wire measurement for RTD’s. All four input leads must be

connected.

– Front Panel operation: Set RTD as the probe type under the 1: PROBE TYPE

command in the TEMPerature menu.

Select the RTD type under the 3: RTD TYPE command in the TEMPerature menu.

Enter the 0 °C resistance of the RTD (R TEMPerature menu.

– Remote operation: Use the following commands for temperature

measurements with RTD’s:

CONFigure:TEMPerature FRTD,{85|91}[,1,<resolution>] MEASure:TEMPerature? FRTD, {85|91}[,1,<resolution>] SENSe:FUNCtion "TEMPerature" SENSe:TEMPerature:TRANsducer:TYPE FRTD SENSe:TEMPerature:TRANsducer:FRTD:TYPE {85|91} SENSe:TEMPerature:TRANsducer:FRTD:RESistance <value>

Features and Functions 3

) must be in the range of 4.9 W to 2.1 kW. RTD

) in the 4: RTD R0 command in the

Thermistor Measurements

– Only the 5 kW thermistor type is supported. Thermistor connections are shown

on page 28.

– The thermistor must be connected to the Channel 1 inputs.

– Front Panel operation: Set THERM as the transducer type under the 1: PROBE

TYPE command in the TEMPerature menu.

– Remote operation: use the following commands for temperature

measurements with a thermistor:

CONFigure:TEMPerature THER, DEF,[,1,<resolution>] MEASure:TEMPerature? THER, DEF,[,1,<resolution>] SENSe:FUNCtion "TEMPerature" SENSe:TEMPerature:TRANsducer:TYPE THER

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3 Features and Functions

NOTE

Thermocouple Measurements

– The thermocouple must be connected to the Channel 2 inputs. Be sure to

observe the correct polarity. Thermocouple connections are shown on

page 30.

– Thermocouple measurements require a reference junction temperature. You

can input a known fixed junction temperature, use an external thermistor temperature, or use the internal thermistor temperature as the reference junction temperature.

The accuracy of the measurement is very dependent upon the thermocouple connections and the reference junction temperature. Use a fixed temperature reference for highest accuracy measurements. The internal thermistor reference produces the lowest accuracy measurements. See page 290 for a discussion of the reference junction temperature measurements.

– Front Panel operation: Set T/C as the probe type under the 1: PROBE TYPE

command in the TEMPerature menu.

Select the thermocouple type under the 4: T/C TYPE command in the Temperature menu.

Set the reference junction temperature source under the 5: COLD JUNCT command in the TEMPerature menu.

If you used a FIXed reference junction temperature, set the reference temperature under the 6: JUNCT TEMP command in the TEMPerature menu. The number entered must be in the range of –1 °C to 55 °C.

– Remote operation: use the following commands for temperature

measurements using thermocouples:

CONFigure:TEMPerature TC,{B|E|J|K|N|R|S|T}[,1,<resolution>] MEASure:TEMPerature? TC,{B|E|J|K|N|R|S|T}[,1,<resolution>] SENSe:

FUNCtion "TEMPerature"

TEMPerature:TRANsducer

:TYPE TC :TCouple

:TYPE {B|E|J|K|N|R|S|T} :RJUNction:TYPE {FIXed|INTernal|THERmistor} :RJUNction {<reference>|MIN|MAX}

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Math Operations

Shift

Stats

Scale

There are two math operations available, only one of which can be enabled at a time. You can choose to either scale the readings as they are taken, or keep statistics on a group of readings. The selected math operation remains in effect until you disable it, change functions, turn off the power, or perform a remote interface reset.

Scaling

– The scaling is applied as:

– Front Panel operation: Set the values of gain and offset in the MATH menu.

Enable scaling by pressing the scale key. The Stats annunciator will light in the display.

– Remote operation: the math operations and registers are controlled using

commands within the CALCulate command subsystem. First, select the math operation you want to use

CALCulate:FUNCtion SCALe

Then, set the values for gain and offset.

CALCulate:SCALe:GAIN <gain>

CALCulate:SCALe:OFFSet <offset>

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

CALCulate:STATe ON

Features and Functions 3

reading = gain * (measurement - offset)

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3 Features and Functions

Stats

Shift

∧

Statistics

– After you enable statistics, the first reading that the meter 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.

– All values are stored in volatile memory; the meter clears the values when stats

is turned on, when power has been off, or after a remote interface reset or preset.

– When enabled, the following statistics are available:

MIN minimum reading MAX maximum reading AVER arithmetic average of all readings STD DEV standard deviation of all readings PEAK – PEAK peak to peak value of minimum and maximum COUNT the total number of readings

– Front Panel operation: Enable the statistics by pressing the key. Read

the statistics gathered in the MATH menu under the STATS command.

After reading the stored statistics, press

(Menu On/Off) to return to

the measurement and continue taking statistics.

– Remote operation: the math operations and registers are controlled using

math operation commands. First, select the math operation you want to use

CALCulate:FUNCtion AVERage

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

CALCulate:STATe ON

When you have finished collecting readings, obtain the desired statistics:

CALCulate:AVERage

:MINimum?

:MAXimum?

:AVERage?

:SDEViation?

:PTPeak?

:COUNt?

After reading the statistics, supply another trigger to continue taking measurements and collecting statistics. Measurements are not taken while reading the results.

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Features and Functions 3

If you are interested in the statistics on a number of readings, but not the readings themselves, you can use the following command:

DATA:FEED RDG_STORE, ""

The null value parameter in the command tells the meter not to store the individual readings. The meter does, however, accumulate statistics on the readings. This method removes the 1024 reading limitation and you can calculate statistics on any number of readings. See page 166 for more

information.

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3 Features and Functions

Null

Null (Relative) Operation

When making null measurements, also called relative, each reading is the difference between the input signal and a stored null value. You could, for example, make a more accurate two-wire ohms measurement by shorting the test

leads and pressing to remove the test lead resistance. See also “To Make

Null (Relative) Measurements” on page 56.

Reading = measurement – null value

– 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 or after a remote interface reset.

– Each function and channel has an independent null value. For voltage

measurements, each input channel has an independent null. Temperature measurement null is applied to all temperature measurements (if you change the probe type, null is still enabled and applied). The null for resistance measurements applies to both 2-wire and 4-wire measurements.

– The null value is stored in the meter’s Null Register. There are two ways you

can specify the null value. First, you can enter a specific number into the register from the front-panel menu or from the remote interface. Any previously stored value is replaced with the new value. If you are operating the meter from

the front panel, entering a null value also turns on the null function.

The second way to enter the null value is to let the meter store the first reading in the register. Press the key to make the displayed measurement the null

value and enable the Null operation. After you enable null, the first reading displayed will be zero. If you entered a number into the register, as described in the paragraph above, the first reading does not overwrite the stored value.

– Since an independent null value is stored for each input channel, difference or

ratio functions also use these null values. Additionally, when using the difference function, an additional difference null can be applied (the difference null is only available from the front panel). See page 79 for a description of how null is applied to difference and ratio functions.

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Features and Functions 3

Shift

∧

– Front-panel operation: After enabling null, you can edit the stored null value

by pressing

(Menu Recall). Any previously stored value is replaced

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

When null is enabled, the ‘Null’ annunciator lights in the display. For ratio or difference measurement, if either input channel has a null enabled, the Null annunciator will flash. If you apply the difference null, the Null annunciator will light (not flash).

– Remote interface operation: You can use the following commands to make

null measurements. Null must be enabled before you can store a value in the

Null Register.

SENSe1 | SENSe2

:VOLTage:DC

:NULL {OFF|ON} :NULL {<value>|MIN|MAX}

[SENSe:]

FRESistance|RESistance

:NULL {OFF|ON} :NULL {<value>|MIN|MAX}

TEMPerature

:NULL {OFF|ON} :NULL {<value>|MIN|MAX}

To enable null and set a null value (0.10) for the 2-wire resistance function execute the following commands in the order shown.

SENS:RES:NULL ON SENS:RES:NULL 0.10

You can use the first reading as a null value from the remote interface by first setting the function, range, and resolution and then executing the following command:

[SENSe:]NULL [{OFF|ON|ONCE}]

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3 Features and Functions

Shift

∧

1: READ HOLD

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 meter beeps and holds the reading on the display.

The reading hold feature is available only from the front panel. If you go to remote when reading hold is enabled, the meter ignores it; when you return to local (front panel), reading hold is enabled again.

– Reading hold has an adjustable sensitivity band (adjustable only from the front

panel) to allow you to select which readings are considered stable enough to be displayed. The band is expressed as a percent of reading, on the selected range. The meter will capture and display a new value only after three consecutive readings are within the band.

Select one of these values: 0.01%, 0.10% (default), 1.00%, or 10.0% of reading.

For example, assume that the 1.00% band is selected and a 5 volt signal is applied to the meter. If three consecutive readings are between 4.95 volts and

5.05 volts, the meter will beep and display a new reading.

– The sensitivity band is stored in volatile memory; the meter sets the band to

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

– If the meter is in autorange when you enable reading hold, it will autorange to

the correct range. If the meter is in the manual range mode, the same fixed range will be used for reading hold.

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

memory. See also “Reading Memory” on page 103.

– Front Panel operation: After enabling reading hold, you can select a different

sensitivity band by pressing

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Page 97

Triggering

Single

Shift

Auto/Hold

Features and Functions 3

The meter’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 meter 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 meter from the front panel, with an external trigger, or use

autotriggering. Single triggering takes one reading each time you press the

key. External triggering is like single triggering, but the meter waits for

a pulse on the rear-panel Ext Trig (external trigger) terminal before taking a reading. Autotriggering takes continuous readings at the fastest rate possible for the present configuration. See also “To Trigger the Meter” on page 59.

– Press to return the meter to auto triggering.

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

– First, you must configure the meter for the measurement by selecting the

function, range, integration time, etc.

– Then, you must specify the source from which the meter will accept the

trigger. The meter 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 meter is ready to accept a trigger from the

specified trigger source (this is called the wait-for-trigger state).

– Finally, to make the measurement, you must provide an INITiate, READ?, or

MEASure command.

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

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3 Features and Functions

Triggering

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Trigger Source Choices

Single

You must specify the source from which the meter will accept a trigger.

– The trigger source is stored in volatile memory; the source is set to autotrigger

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

– Front Panel operation: the meter will accept a either a front panel single

trigger or a hardware trigger from the Ext Trig terminal, or continuously take readings using autotrigger. At power-on, autotriggering is used.

– Remote operation: the meter will accept a software (bus) trigger, a hardware

trigger from the Ext Trig terminal, or an immediate internal trigger. See

“Triggering” on page 93 for more information.

Autotriggering In the autotrigger mode (front panel only), the meter

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 meter by pressing . The meter takes one reading, or the specified number of readings (sample count), each time you press the key. The ‘Trig’ annunciator turns on when the meter is waiting for a trigger.

Features and Functions 3

Pressing the key also allows the meter to accept triggers on the Ext Trig terminal.

The front-panel key is disabled when in remote.

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3 Features and Functions

Single

External Triggering In the external trigger mode, the meter will accept a

hardware trigger applied to the Ext Trig terminal. The meter takes one reading, or the specified number of readings (sample count), each time Ext Trig receives a low-true pulse.

See also “External Trigger Terminal” on page 110.

– The meter buffers one external trigger. This means that if the meter is taking a

reading and another external trigger occurs, that trigger is accepted (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 to enable the single trigger mode also enables the external trigger mode. The ‘Trig’ annunciator turns on when the meter is waiting for an external trigger.

The front-panel key is disabled when in remote.

– Remote operation: Use the following command to enable external trigger.

TRIGger:SOURce EXTernal

96 Keysight 34420A User’s Guide

Keysight 34420A User Manual

Certification

Safety Symbols

Safety Considerations

Environmental Conditions

Waste Electrical and Electronic Equipment (WEEE) Directive

Product category:

Sales and Technical Support

The Front-Panel at a Glance

The Front-Panel Menu at a Glance

Display Annunciators

The Rear Panel at a Glance

In This Book

Table of Contents

1 Quick Start

Quick Start

To Prepare the Meter For Use

If the Meter Does Not Turn On

To Make Input Connections

To Measure Voltage

To Measure Temperature With Thermistors

To Measure Temperature With RTDs

To Measure Temperature With Thermocouples

To Select a Range

To Set the Number of Digits

To Set the Integration Time

Front-Panel Display Formats

To Rack Mount the Meter

2 Front-Panel Operation

Front-Panel Operation

Front-Panel Menu Reference

A Front-Panel Menu Tutorial

To Select an Input Channel

To Select a Range

To Set or Change the Number of Digits

To Set the Integration Time

To Make Null (Relative) Measurements

To Store Minimum and Maximum Readings (Stats)

To Trigger the Meter

To Use Reading Hold

To Make Voltage Ratio and Difference Measurements

To Use Reading Memory

3 Features and Functions

Features and Functions

General Measurement Configuration

Input Filters

Integration Time

Reducing Measurement Noise

Number of Digits Displayed

Ranging

Overload Detection

Voltage Measurement Configuration

Input Channels

Resistance Measurement Configuration

Temperature Measurement Configuration

Measurement Units

RTD Measurements

Thermistor Measurements

Thermocouple Measurements

Math Operations

Null (Relative) Operation

Reading Hold

Triggering

Trigger Source Choices