Agilent Technologies Switch-Measure User Manual

Download

Agilent 34980A Multifunction Switch/Measure Unit

User’s Guide

Agilent Technologies

Notices

No part of this manual may be reproduced 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 Agilent Technologies, Inc. as governed by United States and international copyright laws.

Manual Part Number

34980-90001

Edition

First edition, November 2004

Printed in Malaysia

Agilent Technologies, Inc. 815 14th Street SW Loveland, CO 80537 USA

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, Agilent 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. Agilent 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 Agilent 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.

Technology Licenses

The hardware 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.

Restricted Rights Legend

agency regulation or contract clause. Use, duplication or disclosure of Software is subject to Agilent Technologies’ standard commercial license terms, and non-DOD Departments and Agencies of the U.S. Government will receive no greater than Restricted Rights as defined in FAR

52.227-19(c)(1-2) (June 1987). U.S. Government users will receive no greater than Limited Rights as defined in FAR 52.227-14 (June 1987) or DFAR 252.227-7015 (b)(2) (November 1995), as applicable in any technical data.

Safety Notices

CAUTION

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.

WARNING

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.

If software is for use in the performance of a U.S. Government prime contract or subcontract, Software is delivered and licensed as “Commercial computer software” as defined in DFAR 252.227-7014 (June 1995), or as a “commercial item” as defined in FAR 2.101(a) or as “Restricted computer software” as defined in FAR

52.227-19 (June 1987) or any equivalent

Additional Safety Notices

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

General

Do not use this products in any manner not specified by the manufacturer. The protective features of this product may be impaired if it is used in a manner not specified in the operation instructions.

Before Applying Power

Verify that all safety precautions are taken. Make all connections to the unit before applying power.

Ground the Instrument

This product is provided with protective earth terminals. To minimize shock hazard, the instrument must be connected to the ac power mains through a grounded power cable, with the ground wire firmly connected to an electrical ground (safety ground) at the power outlet. Any interruption of the protective (grounding) conductor or disconnection of the protective earth terminal will cause a potential shock hazard that could result in personal injury.

Do Not Modify the Instrument

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

In Case of Damage

Instruments that appear damaged or defective should be made inoperative and secured against unintended operation until they can be repaired by qualified service personnel.

Safety Symbols

Alternating current

Frame or chassis terminal

Standby supply. Unit is not completely disconnected from ac mains when switch is off

Caution, risk of electric shock

Caution, refer to accompanying description

Do Not Operate in an Explosive Atmosphere

Do not operate the instrument in the presence of flammable gases or fumes.

Do Not Remove the Instrument Cover

Only qualified, service-trained personal who are aware of the hazards involved should remove instrument covers. Always disconnect the power cable and any external circuits before removing the instrument cover.

If you have questions about your shipment, or if you need information about warranty, service, or technical support, contact Agilent Te ch n ol o gi e s:

In the United States: (800) 829-4444

In Europe: 31 20 547 2111

In Japan: 0120-421-345

Or go to www.agilent.com/find/assist for information on contacting Agilent in your country of specific location. You can also contact your Agilent Technologies Representative.

DECLARATION OF CONFORMITY

iii

According to ISO/IEC Guide 22 and CEN/CENELEC EN 45014

Manufacturer’s Name: Manufacturer’ s Add ress:

Declares under sole responsibility that the product as originally delivered Product Name:

Model Number:

Product Options: complies with the essen t ial requirements of the following app li cabl e Eu ropean Directives, and

carries the CE marking accordingly:

Low Voltage Direc tive (73/23/EEC, amended by 93/68/EE C) EMC Directive ( 89/336/EEC, amended by 93/68/EEC)

and conforms with the following product standards:

EMC Standard

IEC 61326-1:1997+A1:1998 / EN 61326-1:1997+A1:1998 CISPR 11:1990 / EN 55011:1991 IEC 61000-4-2:1995+A1:1998 / EN 61000-4-2:1995 IEC 61000-4-3:1995 / EN 61000-4-3:1995 IEC 61000-4-4:1995 / EN 61000-4-4:1995 IEC 61000-4-5:1995 / EN 61000-4-5:1995 IEC 61000-4-6:1996 / EN 61000-4-6:1996 IEC 61000-4-11:1994 / EN 61000-4-11:1994

Canada: ICES-001:1998 Australia/New Zealand: AS/NZS 2064.1

Safety

The product was tested in a typical configuration with Agilent Technologies test systems.

IEC 61010-1:2001 / EN 61010-1:2001 Canada: CSA C22.2 No. 61010.1:2004 USA: UL 61010-1: 2004

Supplementary Information: This DoC applies to above-l isted products placed on the EU market aft er:

Agilent Technologies, Incorporated 815 – 14

St. SW Loveland, CO 80537 USA

Multifunction Switch / Measure Unit 34980A, 34921A/T, 34922A/T, 34923A/T, 34925A/ T, 34931A/T, 34932A/T , 34933A/T, 34937A/T, 34938A/ T, 34941A, 34946A, 34947A, 34951A /T, 34952A/T This declar ation covers all options of the above produc ts

Limit

Group 1 Class A 4 kV CD, 4 kV AD 3 V/m, 80-1000 MHz

0.5 kV signal lines, 1 kV power lines

0.5 kV line-line, 1 kV line-ground 3 V, 0.15-80 MHz, 80% mod Interrupt: 10 ms, 20 ms

9 November 2004

Date

For furth er i nformati on, please c ont act y our l oc al A gi l ent Technol ogies sal es off ice, agent or dis tr i but or ,

or Agilent Technologies Deutschland GmbH, Herrenberger Straße 130, D 71034 Böblingen, Germany.

Ray Corson

Product Regulations Program Manager

Template: A5971-5302-2, Rev. B.00 34980A-DoC-A DoC Revision A

iii

1 Introduction to the 34980A

2 Features and Functions

Front Panel at a Glance 2

Rear Panel at a Glance 3

Rear Panel Connector Pinouts 4

External Trigger Input Connector (Male D-Sub) 4 Analog Bus Connector (Female D-Sub) 4

Annunciator Display Indicators 5

Front Panel Menu Reference 6

Instrument Rack Mounting 7

SCPI Language Conventions 10

Rules for Using a Channel List 10

General Measurement Configuration 12

Overview of Measurement Modes 12 Analog Buses 15 Measurement Functions 16 Measurement Range 17 Measurement Resolution 18 Custom A/D Integration Time 19 Autozero 21 Trigge r Delay 22 Automatic Trigger Delays 23 Safety Interlock 24 User-Defined Channel Labels 25 2-Wire Versus 1-Wire Mode 27

Analog Bus and Internal DMM Considerations 28

Environmental Operating Conditions 28 Electrical Operating Conditions 29

34980A User’s Guide v

Temperature Measurement Configuration 30

Measurement Units 30 Thermocouple Measurements 31 RTD Measurements 33 Thermistor Measurements 34

Voltage Measurement Configuration 35

DC Input Resistance 35 AC Low Frequency Filter 36

Resistance Measurement Configuration 37

Offset Compensation 37

Current Measurement Configuration 38

AC Low Frequency Filter 38

Frequency Measurement Configuration 39

Low Frequency Timeout 39

Mx+B Scaling 40

Scanning 42

Rules for Scanning 42 Adding Channels to the Scan List 44 Scan Trigger Source 46 Trigge r Cou nt 49 Sweep Count 50 Sample Count 51 Channel Delay 53 Automatic Channel Delays 54 Reading Format 56 Non-Sequential Scanning 57 Viewing Readings Stored in Memory 58

Monitor Mode 60

vi 34980A User’s Guide

System-Related Operations 62

Firmware Revision 62 Product Firmware Updates 63 Instrument State Storage 63 Error Conditions 64 Self-Test 66 Front-Panel Display Control 66 Front-Panel Number Format 67 Real-Time System Clock 68 Relay Cycle Count 68 SCPI Language Version 69

Calibration Overview 70

Calibration Security 70 Calibration Count 72 Calibration Message 73

Remote Interface Configuration 74

GPIB Interface 75 USB Interface 75 LAN Interface 75

Factory Reset State 84

Instrument Preset State 86

3 Introduction to the Plug-In Modules for the 34980A

Slot and Channel Addressing Scheme 90

Interconnection Solutions Overview 91

Module Considerations 92

General Considerations 92 Environmental Operating Conditions 92 Electrical Operating Conditions 93

34980A User’s Guide vii

4 Low Frequency Multiplexer Switch Modules

Low Frequency Multiplexer Switch Modules 96

Measurement Functions for the MUX Modules 97 SCPI Programming Examples for the MUX Modules 98

34921A 40-Channel Armature Multiplexer with Low Thermal Offset 102

34921A Simplified Schematic 104 34921A D-Sub Connectors 105 34921T Terminal Block 106

34922A 70-Channel Armature Multiplexer 107

34922A Simplified Schematic 108 34922A D-Sub Connectors 109 34922T Terminal Block 111

34923A 40/80-Channel Reed Multiplexer 112

34923A Simplified Schematic for Two- or Four-Wire Mode 114 34923A D-Sub Connectors for Two- or Four-Wire Mode 116 34923T-001 Terminal Block for Two- or Four-Wire Mode 117 34923A Simplified Schematic for One-Wire Mode 118 34923A D-Sub Connectors for One-Wire Mode 119 34923T-002 Terminal Block for One-Wire Mode 120

34924A 70-Channel Reed Multiplexer 121

34924A Simplified Schematic 123 34924A D-Connectors 124 34924T Terminal Block 126

34925A 40/80-Channel Optically-Isolated FET Multiplexer 127

34925A Simplified Schematic for Two- or Four-Wire Mode 130 34925A D-Sub Connectors for Two- or Four-Wire Mode 131 34925T-001 Terminal Block for Two- or Four-Wire Mode 132 34925A Simplified Schematic for One-Wire Mode 133 34925A D-Sub Connectors for One-Wired Mode 134 34925T-002 Terminal Block for One-Wire Mode 135

viii 34980A User’s Guide

5Matrix Switch Modules

Matrix Switch Modules 138

SCPI Programming Examples for the Matrix Modules 139 Linking Multiple Matrix Modules 142

34931A Dual 4x8 Armature Matrix 144

34931A Simplified Schematic 145 34931A D-Sub Connectors 146 34931T Terminal Block 147

34932A Dual 4x16 Armature Matrix 149

34932A Simplified Schematic 150 34932A D-Sub Connectors 151 34932T Terminal Block 152

34933A Dual/Quad 4x8 Reed Matrix 153

34933A Simplified Schematic for Two-Wire Mode 155 34933A D-Sub Connectors for Two-Wire Mode 156 34933T-001 Terminal Block for Two-Wire Mode 157 34933A Simplified Schematic for One-Wire Mode 159 34933A D-Sub Connectors for One-Wire Mode 160 34933T-002 Terminal Block for One-Wire Mode 161

6 General Purpose Switch Modules

General Purpose Switch Modules 164

34937A and 34938A SCPI Programming Examples 166

34937A 32-Channel GP Switch 168

34937A Simplified Schematic 168 34937A D-Sub Connectors 169 34937T Terminal Block 170

34938A 20-Channel High-Current GP Switch 171

34938A Simplified Schematic 171 34938A D-Sub Connectors 172 34938T Terminal Block 173

7 RF Multiplexer Switch Modules

34941A and 34942A RF Multiplexer Switch Modules 176

Installing SMA Connectors 177 Isolating Connector Banks 177 34941A and 34942A SCPI Programming Examples 178 34941A and 34942A Simplified Schematic 179

34980A User’s Guide ix

8 Dual/Triple Microwave Switch Modules

34946A and 34947A Dual/Triple Microwave Switch Modules 182

34946A and 34947A SCPI Programming Examples 182 Installing SMA Connectors 183 34946A and 34947A Simplified Schematics 184

9 4-Channel Isolated D/A Converter with Waveform Memory Module

34951A 4-Channel Isolated D/A Converter with Waveform Memory Module 186

34951A SCPI Programming Examples 189 34951A Simplified Schematics 193 34951A D-Sub Connector Pinout 194 34951T Terminal Block 195

10 Multifunction Module with DIO, D/A, and Totalizer

34952A Multifunction Module 198

Digital Input/Output 198 Totalizer Input 198 Analog Output (DAC) 198 34952A SCPI Programming Examples 199 34952A Simplified Schematic 201 34952 D-Sub Connector 202 34952T Terminal Block 203

x 34980A User’s Guide

Agilent 34980A Multifunction Switch/Measure Unit User’s Guide

1 Introduction to the 34980A

Front Panel at a Glance 2

Rear Panel at a Glance 3

Rear Panel Connector Pinouts 4

Annunciator Display Indicators 5

Front Panel Menu Reference 6

Instrument Rack Mounting 7

Agilent Technologies

1 Introduction to the 34980A

Front Panel at a Glance

On/Standby switch WARNINGss This switch is standby only. To disconnect the mains from the instrument,

remove the power cord. Utility menu contains settings for Remote I/O (LAN, GPIB, and USB), Date and Time, and other

system-related instrument parameters Store/recall menu allows you to save and recall up to six instrument setups

Control keys directly control module actions

Number keypad enters numerical characters

Exponent

Cancel key exits a menu without saving changes

Arrow keys move cursor positions

Knob enters alphanumeric characters, selects slots, channels, and navigates menus

Enter key steps you through a menu or saves number entries

Running a program puts the display into “remote” and disables the front panel keys. Local takes you out of

“remote” mode and enables the front panel keys. Configure keys select functions and set function parameters

Measure keys execute and monitor measurements. Depending on which measurement key you use, you can

have complete/direct control over the switching and measurement operation, or you can have the 34980A automatically control these to capture the desired data.

2 34980A User’s Guide

WARNING

Rear Panel at a Glance

Introduction to the 34980A 1

Access to Analog Buses (shown with cover installed). For pinout, see page 4.

Module installed in slot 1

Slot identifier

Module ground screw

Slot cover over slot 2

AC power connector

LAN connector (10Base T/100Base Tx)

USB 2.0 connector

External trigger input. For pinout, see page 4.

Internal DMM option mark. If you ordered the internal DMM option, the circle is marked black.

IEEE 488.2 GPIB Connector

Chassis ground screw

34980A User’s Guide 3

1 Introduction to the 34980A

Rear Panel Connector Pinouts

External Trigger Input Connector (Male D-Sub)

Ext Trig Input (Pin 6)

Gnd (Pin 9)

Analog Bus Connector (Female D-Sub)

ANALOG BUSSES

ABus1 HI (Pin 9) ABus2 HI (Pin 8) ABus3 HI (Pin 7) ABus4 HI (Pin 6)

Input

5 V

0 V

> 1 µs

Current I (Pin 5) ABus1 LO (Pin 4) ABus2 LO (Pin 3) ABus3 LO (Pin 2) ABus4 LO (Pin 1)

4 34980A User’s Guide

Annunciator Display Indicators

Introduction to the 34980A 1

Display Indicator Definition

LAN Communicating with the 34980A over LAN USB Communicating with the 34980A over USB GPIB Communicating with the 34980A over GPIB ABUS [1234] Analog Bus Connectivity. Normally, designated ABus connected on any module in mainframe.

During scan, if ABus 1 and ABus 2 are indicated, they will be used at some point during the scan

ERROR

Rmt Remote. Running a program puts the display into “remote” and disables the front panel keys.

Safety Interlock ABus safety interlock. Terminal block or cables have been removed from the D-sub connector of a

Trig Waiting for external or manual trigger during scans

HOT

ALARM (H1234L) Additional functionality to be implemented Bell Symbol Additional functionality to be implemented Mx+B Scaling enabled on channel. This appears on display after you select scaling function via front panel

4W 4-wire measurement specified on channel. This appears on display after you select the 4-wire

OC Offset Compensation specified on channel. This appears on display after you have selected the

(left side of display) Measurement is in progress

An error has been generated and is in the error queue

Pressing the LOCAL button takes you out of “remote” mode and enables the front panel keys.

module. For more information, see page 96 and page 138.

Over-temperature condition. One or more general purpose (34937A/34938A) modules have reached their over-temperature limits.

or remote interface

function via the front panel or remote interface.

offset compensation function via the front panel or remote interface.

34980A User’s Guide 5

1 Introduction to the 34980A

Front Panel Menu Reference

This section gives an overview of the top two levels of menus that you access from the front panel. The menus are designed to automatically guide you through all parameters required to configure a particular function or operation.

Store/Recall Store and recall instrument states

• Store up to six instrument states in non-volatile memory

• Assign a name to each storage location.

• Recall stored states, power-down state, factory reset state, or preset state

Utility Configure system-related instrument parameters

• Connecting and configuring to use with LAN, GPIB, or USB

• Set the real time clock and calendar

• Set radix character, thousand separator

• Enable/disable the internal DMM

• Secure/unsecure the instrument for calibration

• Query and update the firmware revisions for the mainframe and modules

Configure Key Group Set parameters for measurement

DMM

• Set DMM measurement function (AC volts, DC volts, AC current, DC current, 2-wire ohms, 4-wire ohms,

temperature, frequency, and period

• Set function parameters

Channel

• Set channel measurement function (AC volts, DC volts, AC current (34921A only), DC current (34921A only)

2-wire ohms, 4-wire ohms, temperature, frequency, and period

• Set function parameters

Scan

• Set up trigger-in parameters

• Set up sweep count

• Set up sample count

Sequences

Available at a later firmware release

Module

• Open all relays

• Clear all measurement functions

• Clear channel labels

• Configure external trigger and clock (34951A)

• Set trace or level mode (34951A)

• Set waveform parameters (34951A)

6 34980A User’s Guide

View

• View readings, alarms, and errors

• View the scanned readings from memory

• View errors in the error queue

• Read the number of cycles for the displayed relay (relay maintenance feature).

Advanced

Available at a later firmware release

Alarm

Available at a later firmware release

Instrument Rack Mounting

Introduction to the 34980A 1

Using the optional Agilent Y1130A Rack Mount Kit, you can mount the 34980A in a standard 19- inch rack cabinet. The kit includes hardware and instructions to forward or reverse mount the instrument in a cabinet.

34980A User’s Guide 7

1 Introduction to the 34980A

8 34980A User’s Guide

Agilent 34980A Multifunction Switch/Measure Unit User’s Guide

2 Features and Functions

SCPI Language Conventions 10

General Measurement Configuration 12

Analog Bus and Internal DMM Considerations 28

Temperature Measurement Configuration 30

Voltage Measurement Configuration 35

Resistance Measurement Configuration 37

Current Measurement Configuration 38

Frequency Measurement Configuration 39

Mx+B Scaling 40

Scanning 42

Monitor Mode 60

System-Related Operations 62

Calibration Overview 70

Remote Interface Configuration 74

Factory Reset State 84

Instrument Preset State 86

You will find that this chapter makes it easy to look up all the details about a particular feature of the Agilent 34980A. Whether you are operating the instrument from the front panel or over the remote interface, this chapter will be useful. For information specific to the 34980A plug- in modules, see the later chapters in this manual.

NOTE

For complete details on the SCPI (Standard Commands for Programmable Instruments) commands, see the Programmer’s Reference Help file included on the Agilent 34980A Product Reference CD-ROM. The CD-ROM is located inside the rear cover of this manual.

Agilent Technologies

2 Features and Functions

SCPI Language Conventions

Throughout this guide, the following conventions are used for SCPI command syntax for remote interface programming:

• Braces ( { } ) enclose the parameter choices for a given command

string. The braces are not sent with the command string.

• A vertical bar ( | ) separates multiple parameter choices for a given

command string.

• Triangle brackets ( < > ) indicate that you must specify a value for the

enclosed parameter. The brackets are not sent with the command string.

• Some parameters are enclosed in square brackets ( [ ] ). This indicates

that the parameter is optional and can be omitted. The brackets are not sent with the command string. If you do not specify a value for an optional parameter, the instrument chooses a default value.

Rules for Using a Channel List

Many of the SCPI commands for the 34980A include a channel list parameter which allows you to specify one or more channels. From the remote interface, the channel number has the form (@sccc), where s is the mainframe slot number (1 through 8) and ccc is the channel number. You can specify a single channel, multiple channels, or a range of channels.

The following command closes channel 10 on the module in slot 3.

ROUT:CLOS (@3010)

The following command closes channels 10, 12, and 15 on the module in slot 2.

ROUT:CLOS (@2010,2012,2015)

The following command closes channels 5 through 10 (slot 1) and channel 15 (slot 2). When you specify a range of channels, any channels that are invalid will be ignored (no error will be generated) but the first and last channel in the range must be valid.

ROUT:CLOS (@1005:1010,2015)

10 34980A User’s Guide

Features and Functions 2

The Analog Bus relays (numbered s911, s912, s913, etc.) on the multiplexer and matrix modules are ignored if they are included in a range of channels. An error will be generated if an Analog Bus relay is specified as the first or last channel in a range of channels. For example, the following command closes all valid channels between channel 30 (slot 1) and channel 5 (slot 2). In addition, this command closes Analog Bus relay 911 on the module in slot 1 (Bank 1). Note that although the specified range of channels includes the other Analog Bus relays, they are ignored and are not closed by this command.

ROUT:CLOS (@1030:2005,1911)

The following command will generate an error since the Analog Bus relays cannot be specified as the first or last channel in a range of channels (none of the channels will be closed).

ROUT:CLOS (@1005:1911) !Generates an error

In the following command, since the optional <ch_list> parameter is omitted, the command will be applied to the internal DMM. If the internal DMM is disabled or is not present, an error will be generated.

INP:IMP:AUTO ON !Applies to the internal DMM

34980A User’s Guide 11

2 Features and Functions

General Measurement Configuration

This section contains general information to help you configure the instrument for making measurements. Since these parameters are used by several measurement functions, the discussion is combined into one common section. Refer to the later sections in this chapter for more information on parameters that are specific to each measurement function.

Overview of Measurement Modes

Two modes of operation are available with the 34980A, depending on the level of switching and measurement that you wish to directly control: the Stand- Alone DMM Mode and the Scanning Mode.

Stand-Alone DMM Mode

In the Stand- Alone DMM Mode, the internal DMM makes measurements of whatever signals are present on the Analog Buses. In this mode, you have full control of what channel relays are closed and connected to the appropriate Analog Bus for the measurement. You can route your signals directly to the internal DMM using the 34980A multiplexer and matrix modules, or you can connect to external signals via the Analog Bus connector located on instrument’s rear panel (see “Analog Buses” on page 15).

Front Panel Operation:

• To configure the most common measurement parameters for the

internal DMM, use the DMM (Configure) key.

• To close the desired channel relays and Analog Bus relays, use the

Close key. The Analog Bus relays on the multiplexer and matrix modules are numbered s911, s912, s913, etc.

• To auto-trigger the internal DMM and display continuous readings,

press the DMM (Measure) key. Press the DMM (Measure) key again to stop taking measurements.

• For additional triggering control and to store DMM readings in memory,

use the Scan (Configure) key to set the triggering parameters, and then press and hold the Scan (Measure) key to initiate the DMM measurement. These selections are available only for stand- alone DMM use when a scan list has not been defined (see “Stand- Alone DMM Mode” on page 12).

• To stop storing readings in memory during long measurements,

press and hold the Scan (Measure) key.

12 34980A User’s Guide

Features and Functions 2

• To view the readings in memory, use the View key (the readings are

not erased when you read them). Each time you initiate a new DMM- only scan, the instrument will clear the previous set of readings from memory.

Remote Interface Operation:

• You can use the MEASure? command without specifying a <ch_list> to

quickly take a stand- alone DMM reading. Note, however, that with the

MEASure? command, most measurement parameters are set to their

default values.

• To close the desired channel relays and Analog Bus relays, use the

ROUTe:CLOSe command. The Analog Bus relays on the multiplexer and

matrix modules are numbered s911, s912, s913, etc.

• To directly control all measurement parameters or triggering, use the

CONFigure, SENSe, and TRIGger commands without specifying a

<ch_list> parameter. To initiate the measurement, use the INITiate or

READ? command without specifying a <ch_list>. Each time you initiate a

new measurement, the instrument will clear the previous set of readings from memory.

• To stop a measurement in progress, use the

• To view the readings in memory, use the

ABORt command.

FETCh? command

(the readings are not erased when you read them).

Scanning Mode

In the Scanning Mode, the 34980A automatically controls a sequence of measurements using the internal DMM, possibly across multiple channels, and stores the results in memory. The 34980A closes and opens the appropriate channel relays and Analog Bus relays required for the sequence. The following general rules apply to the Scanning Mode (for more information on using the Scanning Mode, see “Scanning” on page 42.)

• Any channel that can be “read” by the instrument can also be included

in a scan. A scan can also include a read of a digital channel or a read of the totalizer count on the digital modules.

• Before you can initiate a scan, you must set up a scan list to include all

desired multiplexer or digital channels. Channels which are not in the scan list are skipped during the scan.

• The Analog Bus relays are automatically opened and closed as required

during the scan to connect to the internal DMM for the measurement. For example, all 2- wire measurements use the ABus1 (MEAS) relays; for 4- wire measurements, the ABus2 (SENS) relays are used in addition to the ABus1 relays.

• Each time you initiate a new scan, the instrument will clear the

previous set of readings from memory.

34980A User’s Guide 13

2 Features and Functions

Front Panel Operation:

• To configure the measurement parameters and add a channel to the

• To initiate a scan and store all readings in memory, press the

• To stop a scan in progress, press and hold the Scan (Measure) key.

scan list, use the Channel (Configure) key.

Scan (Measure) key. If you press the Scan (Measure) key with no

scan list defined, the instrument initiates a DMM- only measurement (see “Stand- Alone DMM Mode” below).

• To view the readings in memory, use the

View key (the readings are not

erased when you read them).

Remote Interface Operation:

• To define the list of channels to be included in the scan list, use the

ROUTe:SCAN command.

• To configure the measurement parameters on the desired channels,

use the

• To initiate a scan and store all readings in memory, use the

CONFigure and SENSe commands.

INITiate

or READ? command. Each time you initiate a new scan, the instrument will clear the previous set of readings from memory.

• To stop a scan in progress, use the

• To view the readings in memory, use the

ABORt command.

FETCh? command

(the readings are not erased when you read them).

NOTE

You can use the READ? command in one of three forms depending on which measurement mode you wish to use.

• If you omit the optional <ch_list> parameter and a scan list is not currently defined, the READ? command applies to the internal DMM.

• If you omit the optional <ch_list> parameter and a scan list is

currently defined, the READ? command performs a scan of the channels in the scan list.

• If you specify a <ch_list>, regardless of whether a scan list is currently defined, the READ? command performs a “temporary” scan of the specified channels (independent of the present scan list).

NOTE

You can use the MEASure? command in one of two forms depending on which measurement mode you wish to use.

• If you omit the optional <ch_list> parameter, the MEASure? command applies to the internal DMM.

• If you specify a <ch_list>, the MEASure? command performs a “temporary” scan of the specified channels (independent of the present scan list).

14 34980A User’s Guide

Analog Buses

The 34980A provides four 2- wire internal Analog Buses for easier signal routing. You can route your measurements directly to the internal DMM using the 34980A multiplexer and matrix modules, or you can connect to external signals via the Analog Bus connector located on the instrument’s rear panel (see connector pinout below). Since four 2- wire buses are provided, you can dedicate one bus for use with the internal DMM and use the other three buses for module extensions or additional signal routing between modules.

ABus1 HI (Pin 9) ABus2 HI (Pin 8) ABus3 HI (Pin 7) ABus4 HI (Pin 6)

ANALOG BUSSES

Features and Functions 2

Current I (Pin 5) ABus1 LO (Pin 4) ABus2 LO (Pin 3) ABus3 LO (Pin 2) ABus4 LO (Pin 1)

Analog Bus connector (as viewed from rear of instrument)

34980A User’s Guide 15

2 Features and Functions

Measurement Functions

The following table shows which DMM measurement functions are supported by each of the multiplexer modules.

Note that similar considerations must be taken into account on the 34931A, 34932A, and 34933A matrix modules. Since the matrix modules cannot be incorporated into a scan list, you must use the Stand- Alone DMM Mode for these modules.

34921A

40-Ch Arm

MUX

Function

34922A

70-Ch Arm

MUX

34923A

40-Ch Reed

MUX

(2-Wire)

34923A

80-Ch Reed

MUX

(1-Wire)

34924A

70-Ch Reed

MUX

34925A

40-Ch FET

MUX

(2-Wire)

34925A

80-Ch FET

MUX

(1-Wire)

Vo ltag e , A C /DC Yes Yes Yes Yes Yes Ye s Yes

Current, AC/DC Yes

No No No No No No

Frequency/Period Yes Yes Yes Yes Yes Yes Yes

Ye s

3,4

Oh m s 2 -W i r e Yes Yes Yes

Oh m s 4 -W i r e Yes Yes Yes

Thermocouple Yes

Ye s

RTD 2 - W i r e Yes Yes Yes

RTD 4 - W i r e Yes Yes Yes

The r m i stor Ye s Yes Yes

Direct current measurements are allowed on channels 41 through 44 only (for all other channels, external shunts are required).

Optional 34921T Terminal Block is required for thermocouple measurements with built-in internal reference junction.

A fixed or external reference junction temperature is required for thermocouple measurement with this module.

Impact of higher offset voltage specification (< 50 µV) must be taken into consideration.

1 kΩ or higher range used unless 100Ω series resistors are bypassed on module.

10 kΩ or higher range used for loads over approximately 300Ω due to series resistance of FET channels.

Ye s

No Yes

3,4

Ye s

No Yes

Ye s

3,4

Ye s

No No

Ye s

No No

Front Panel Operation: DMM or Channel (Configure) > DMM MEASUREMENT

Use the knob (or numeric keypad) to select the desired channel. Then select the desired measurement function for this channel. You are automatically guided to the next level of the menu where you can configure other measurement parameters (range, integration time, etc.).

Remote Interface Operation: You can select the measurement function using

the

CONFigure and MEASure? commands. For example, the following

command configures the specified channel for dc voltage measurements.

CONF:VOLT:DC 10,DEF,(@3001)

16 34980A User’s Guide

Measurement Range

You can allow the instrument to automatically select the measurement range using autoranging or you can select a fixed range using manual ranging. Autoranging is convenient because the instrument decides which range to use for each measurement based on the input signal. For fastest scanning operation, use manual ranging on each measurement (some additional time is required for autoranging since the instrument has to make a range selection).

• Autorange thresholds:

Features and Functions 2

Down range at: Up range at:

<10% of range >120% of range

• If the input signal is greater than can be measured on the selected

range (manual ranging), the instrument gives an overload indication: “±OVLD” from the front panel or “±9.9E+37” from the remote interface.

• For temperature measurements, the instrument internally selects the

range; you cannot select which range is used. For thermocouple measurements, the instrument internally selects the 100 mV range. For thermistor and RTD measurements, the instrument autoranges to the correct range for the transducer resistance measurement.

• For frequency and period measurements, the instrument uses one

“range” for all inputs between 3 Hz and 300 kHz. The range parameter is required only to specify the resolution. Therefore, it is not necessary to send a new command for each new frequency to be measured.

• The

CONFigure and MEASure? commands contain an optional parameter

which allows you to specify the range or autoranging.

• The instrument returns to autoranging when the measurement function

is changed and after a Factory Reset (

*RST command). An Instrument

Preset (SYSTem:PRESet command) or Card Reset (SYSTem:CPON command) does not change the range setting.

Front Panel Operation: DMM or Channel (Configure) > RANGE

First, select the measurement function on the active channel. You are automatically guided to the next level of the menu where you can select a specific range or autoranging.

Remote Interface Operation: You can select the range using parameters in

the CONFigure and MEASure? commands. For example, the following command selects the 10 Vdc range on the specified channel.

CONF:VOLT:DC 10,DEF,(@3001)

34980A User’s Guide 17

2 Features and Functions

Measurement Resolution

Resolution is expressed in number of digits the internal DMM can measure or display on the front panel. You can set the resolution to 4, 5, or 6 full digits, plus a “½” digit which can be “0” or “1”. To increase the measurement accuracy and improve noise rejection, select 6½ digits. To increase the measurement speed, select 4½ digits.

• For ac voltage measurements, the resolution is fixed at 6½ digits.

• The specified resolution is used for all measurements on the selected

• Changing the number of digits does more than just change the

The only way to control the reading rate for ac measurements is by changing the channel delay (see page 53) or by setting the ac filter to the highest frequency limit (see page 36).

channel. If you have applied Mx+B scaling or have assigned alarms to the selected channel, those measurements are also made using the specified resolution. Measurements taken during the Monitor function also use the specified resolution.

resolution of the instrument. It also changes the integration time, which is the period the instrument’s analog- to- digital (A/D) converter samples the input signal for a measurement. See “Custom A/D

Integration Time” on page 19 for more information.

• The

CONFigure and MEASure? commands contain an optional parameter

which allows you to specify the resolution.

• The instrument returns to 5½ digits when the measurement function is

changed and after a Factory Reset (

*RST command). An Instrument

Preset (SYSTem:PRESet command) or Card Reset (SYSTem:CPON command) does not change the resolution setting.

Front Panel Operation: DMM or Channel (Configure) > INTEGRATION > NPLC

First, select the measurement function on the active channel. You are automatically guided to the next level of the menu where you can select a specific resolution.

Remote Interface Operation: Specify the resolution in the same units as

the measurement function, not in number of digits. For example, if the function is dc voltage, specify the resolution in volts. For frequency, specify the resolution in hertz.

You can select the resolution using parameters in the

MEASure? commands. For example, the following command selects the

CONFigure and

10 Vdc range with 4½ digits of resolution on the specified channel.

CONF:VOLT:DC 10,0.001,(@3001)

18 34980A User’s Guide

The following command selects the 1 A range with 6½ digits of resolution on channel 2041 (current measurements are allowed only on channels 41 through 44 on the 34921A).

MEAS:CURR:AC? 1,1E-6,(@2041)

You can also select the resolution using the SENSe commands. For example, the following command specifies a 2- wire ohms measurement with 100Ω of resolution on channel 1003.

SENS:RES:RES 100,(@1003)

Custom A/D Integration Time

Integration time is the period of time the internal DMM’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 (PLCs). Select from 0.02, 0.2, 1, 2, 10, 20, 100, or 200 power line cycles.

The default is 1 PLC.

Features and Functions 2

• Only integral number of power line cycles (1, 2, 10, 20, 100, or 200 PLCs) provide normal mode (line frequency noise) rejection.

• You can also specify integration time directly in seconds (this is called aperture time). Select a value between 300 µs and 1 second, with 4 µs resolution.

• The only way to control the reading rate for ac measurements is by changing the channel delay (see “Channel Delay” on page 53) or by setting the ac filter to the highest frequency limit (see “AC Low

Frequency Filter” on page 36).

• The specified integration time is used for all measurements on the selected channel. If you have applied Mx+B scaling or have assigned alarms to the selected channel, those measurements are also made using the specified integration time. Measurements taken during the Monitor function also use the specified integration time.

34980A User’s Guide 19

2 Features and Functions

• The following table shows the relationship between integration time,

Relationship between integration time, resolution, digits, and bits

Integration Time Resolution Digits Bits

measurement resolution, number of digits, and number of bits.

0.02 PLC

0.2 PLC

1 PLC

2 PLC

10 PLC

20 PLC 100 PLC 200 PLC

< 0.0001 x Range < 0.00001 x Range

< 0.000003 x Range

< 0.0000022 x Range

< 0.000001 x Range

< 0.0000008 x Range < 0.0000003 x Range < 0.00000022 x Range

4½ Digits 5½ Digits

5½ Digits

6½ Digits

6½ Digits 6½ Digits 6½ Digits

15 18

25 26 26

• The instrument selects 1 PLC when the measurement function is changed and after a Factory Reset (

*RST command). An Instrument

Preset (SYSTem:PRESet command) or Card Reset (SYSTem:CPON command) does not change the integration time setting.

Front Panel Operation: DMM or Channel (Configure) > INTEGRATION > TIME

First, select the measurement function on the active channel. You are automatically guided to the next level of the menu where you can select a specific integration time.

Remote Interface Operation: You can set the integration time using the

SENSe commands. For example, the following command specifies an

aperture time of 2 ms for resistance measurements on channel 2001.

SENS:RES:APER 0.002,(@2001)

20 34980A User’s Guide

Autozero

Features and Functions 2

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

When autozero is disabled, the instrument takes one zero reading and subtracts it from all subsequent measurements. It takes a new zero reading each time you change the function, range, or integration time.

• Applies to temperature, dc voltage, resistance, temperature, and dc current measurements only.

• The autozero mode is set indirectly when you set the resolution and integration time. Autozero is automatically turned off when you select an integration time less than 1 PLC.

• The

CONFigure and MEASure? commands automatically enable autozero.

• The autozero setting is stored in non- volatile memory, and does not change when power has been off, after a Factory Reset (

*RST

command), or after an Instrument Preset (SYSTem:PRESet command).

Front Panel Operation: DMM or Channel (Configure) > AUTO ZERO

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

effect. Autozero OFF does not issue a new zero measurement. Autozero ONCE issues an immediate zero measurement.

[SENSe:]<function>:ZERO:AUTO {OFF|ONCE|ON} [,(@<ch_list>)]

34980A User’s Guide 21

2 Features and Functions

Trigger Delay

In some applications, you want to allow the input to settle before taking a reading or for pacing a burst of readings. You can add a trigger delay, which adds a delay between the trigger signal and the first sample taken by the internal DMM (not used in Scanning Mode). The programmed trigger delay overrides the default trigger delay that the instrument automatically adds to the measurement.

Sample CountTrigger 1 Sample CountTrigger 2

Trigger Delay

(0 to 3600 seconds)

Trigger delay

• The default trigger delay is Automatic (see “Automatic Trigger

Delays” on page 23); the instrument determines the delay based on

function, range, and integration time.

• If you specify a trigger delay other than Automatic, that same delay is used for all functions and ranges.

• If you have configured the instrument to take more than one reading per trigger (sample count > 1), the specified trigger delay is inserted between the trigger and the first reading in the sample burst.

• The

CONFigure and MEASure? commands set the trigger delay to

Automatic.

• The instrument selects an automatic trigger delay after a Factory Reset

*RST command). An Instrument Preset (SYSTem:PRESet command) or

( Card Reset (

SYSTem:CPON command) does not change the setting.

22 34980A User’s Guide

Automatic Trigger Delays

If you do not specify a trigger delay, the instrument selects a delay for you. The delay is determined by the function, range, integration time, and ac filter setting as shown below.

DC Voltage, Thermocouple, DC Current (for all ranges):

Integration Time Trigger Delay

Features and Functions 2

PLC > 1 PLC ≤ 1

2.0 ms

1.0 ms

Resistance, RTD, Thermistor (2- and 4-wire):

Trigger Delay

Range

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

(for PLC > 1) Range

2.0 ms

2.0 ms 25 ms 30 ms 200 ms 200 ms

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

AC Voltage, AC Current (for all ranges):

AC Filter Trigger Delay

Slow (3 Hz) Medium (20 Hz) Fast (200 Hz)

7.0 seconds

1.0 second 120 ms

Trigger Delay (for PLC ≤ 1)

1.0 ms

1.0 ms 20 ms 25 ms 200 ms 200 ms

Frequency, Period:

AC Filter Trigger Delay

Slow (3 Hz) Medium (20 Hz) Fast (200 Hz)

600 ms 300 ms 100 ms

Digital Input, Totalize:

Trigger Delay

0 seconds

34980A User’s Guide 23

2 Features and Functions

Safety Interlock

The Safety Interlock feature prevents connections to the Analog Buses if no terminal block or properly- wired cable is connected to a module (available on multiplexer and matrix modules only).

Normally, if you attempt to connect to the Analog Buses without a terminal block or properly- wired cable connected, an error is generated. You c a n , however, temporarily disable errors generated by the Safety Interlock feature. This simulation mode may be useful during test system development when you may not have connected any terminal blocks or cables to your module.

This feature is available from the remote interface only

CAUTION

• The simulation mode applies to the entire mainframe and cannot be selectively used on individual modules.

• When the simulation mode is enabled, the Analog Bus relays will appear to close and open as directed. For example, no errors are generated if you close an Analog Bus relay from the front panel, remote interface, or Web Interface. However, remember that the Safety Interlock feature prevents the actual hardware state of the Analog Bus relays from being changed. When you connect a terminal block or cable to the module, the Analog Bus relays will be closed.

• The simulation setting is stored in volatile memory and will be lost when power is turned off. To re- enable the simulation mode after power has been off, you must send the command again.

The Safety Interlock feature is implemented in hardware on the modules and cannot be circumvented. Regardless of whether the simulation mode is enabled or disabled, all Analog Bus connections are prohibited as long as no terminal block or properly-wired cable is connected to the module.

Remote Interface Operation: SYSTem:ABUS:INTerlock:SIMulate {OFF|ON}

24 34980A User’s Guide

User-Defined Channel Labels

You can assign user- defined labels to any channel, including Analog Bus channels on the multiplexer and matrix modules. User- defined channel labels are available for identification purposes only and cannot be used in place of a channel number within a command string.

• When shipped from the factory, each channel is assigned a unique factory- default label (cannot be overwritten). From the front panel, the factory- default labels are shown on the upper line of the display (e.g., “MUX CH BANK 1”, “MATRIX1 ROW3 COL4”, “DIO BYTE 1”, etc.). From the Web Interface, the factory- default labels are displayed as the channel number (e.g., “1001”, “3020”, etc.).

• If desired, you can assign the same user- defined label to multiple channels within the same module or on different modules (i.e., channel labels are not required to be unique).

• You can specify a label with up to 18 characters. You can use letters (A- Z), numbers (0- 9), and the underscore character. If you specify a label with more than the allowed 18 characters, it will be truncated (no error is generated).

Features and Functions 2

• From the Web Interface, a limited number of characters can be displayed due to space constraints in the browser window. If the user- defined label it too long to be displayed properly, it will be truncated (no error is generated).

• The instrument keeps a record of what module types are installed in each slot. If a different module type is detected in a specific slot at power on, all user- defined channel labels for that slot are discarded. If an empty slot is detected at power- on, any previously- defined labels for that slot are preserved and will be restored if the same module type is installed later; however, if a module of a different type is installed in that slot, the previously- defined labels will be discarded.

• All user- defined channel labels are stored in non- volatile memory, and do not change when power has been off, after a Factory Reset

*RST command), after an Instrument Preset (SYSTem:PRESet

( command), or after a stored state is recalled (*RCL command).

34980A User’s Guide 25

2 Features and Functions

Front Panel Operation: Channel (Configure) > CHANNEL LABEL

To define the channel label, press the arrow keys to move the cursor to a specific position and then turn the knob to select the desired letter or number.

To clear the channel label on the selected channel, change each character to “ ^ ” (starting with the rightmost character) and then press the left arrow key to move to the next character.

To clear all channel labels on the selected module, navigate to:

Module (Configure) > CLEAR LABELS? > YES

Remote Interface Operation: The following command assigns a label

(“TEST_PT_1”) to channel 3 in slot 1.

ROUT:CHAN:LABEL "TEST_PT_1",(@1003)

The following command clears the user- defined label previously assigned to channel 3 in slot 1. The channel will now be identified by its factory default label (e.g., “MUX CH BANK 1”, “MATRIX1 ROW3 COL4”, “DIO BYTE 1”, etc.).

ROUT:CHAN:LABEL "",(@1003)

The following command clears all user- defined channel labels on the module in slot 1. The factory-default labels are assigned to all channels on the module in slot 1.

ROUT:CHAN:LABEL:CLEAR:MOD 1

The following command clears all user- defined labels on all modules installed in the 34980A. The factory- default labels are assigned to all channels on all installed modules.

ROUT:CHAN:LABEL:CLEAR:MOD ALL

26 34980A User’s Guide

2-Wire Versus 1-Wire Mode

You can configure the 34923A, 34925A, and 34933A modules for 2- wire (differential) or 1-wire (single ended) measurements. If you change the module configuration, you must cycle power on the 34980A to activate the new setting.

• To determine whether the module is in the 2- wire or 1- wire configuration, check the module description shown on the front panel when the module is selected, or send the

SYSTem:CDEScription? command. For example, the SYSTem:CTYPe?

response for the 34923A will be either “34923A” (differential mode) or “34923A-1W” (single- ended mode).

• If you are using terminal blocks with these modules, be sure to use the corresponding 2- wire or 1- wire terminal block.

• The module configuration is stored in non- volatile memory on the module and does not change when you remove the module from the mainframe, after a Factory Reset ( Instrument Preset (SYSTem:PRESet command).

Features and Functions 2

SYSTem:CTYPe? or

*RST command), or after an

Front Panel Operation: Module (Configure) > MODE NEXT POWER-ON

After selecting the 2- wire (“WIRE2”) or 1- wire (“WIRE1”), you must cycle power on the 34980A to activate the new setting.

Remote Interface Operation: The following command selects the 1- wire

configuration on the module in slot 3. The new configuration will not take effect until you cycle power on the 34980A.

SYST:MOD:WIRE:MODE WIRE1,3

34980A User’s Guide 27

2 Features and Functions

Analog Bus and Internal DMM Considerations

This section provides important environmental and electrical considerations that can affect mainframe operation.

Environmental Operating Conditions

The 34980A mainframe, including the optional internal DMM, is designed to operate in a temperature range of 0 °C to +55 °C with non-condensing humidity. The maximum humidity is 80% at 40 °C or higher. Do not use in locations where conductive dust or electrolytic salt dust may be present.

The 34980A should be operated in an indoor environment where temperature and humidity are controlled. Condensation can pose a potential shock hazard. Condensation can occur when the instrument is moved from a cold to a warm environment, or if the temperature and/or humidity of the environment changes quickly.

When used in pollution degree 1 conditions, the maximum voltage rating for the Analog B uses is 300V. When used in pollution degree 2 conditions, the maximum voltage rating is 100V. If conditions change, ensure that condensation has evaporated and the instrument has thermally stabilized until pollution degree 1 conditions are restored before turning on power to the equipment.

NOTE

Pollution Degree 1: No pollution or only dry, non-conductive pollution occurs. The pollution has no influence (on insulation) (IEC 61010-1 2nd Edition).

Pollution Degree 2: Normally only non-conductive pollution occurs. Occasionally, a temporary conductivity (leakage current between isolated conductors) caused by condensation can be expected (IEC 61010-1 2nd Edition).

28 34980A User’s Guide

Electrical Operating Conditions

Features and Functions 2

WARNING

To avoid electric shock, turn off the 34980A and disconnect or de-energize all field wiring to the modules and the Analog Bus connector before removing any module or slot cover.

Tr an s ie n ts

The Analog Buses and the optional internal DMM are designed to safely withstand occasional transient overvoltages up to 1000 Vpeak. Typically, these transient overvoltages result from switching inductive loads or from nearby lightning strikes. The lightning- caused transient overvoltages that may occasionally occur on mains power outlets may be as high as 2500 Vpeak.

WARNING

Do not connect the Analog Buses directly to a mains power outlet. If it is necessary to measure a mains voltage or any circuit where a large inductive load may be switched, you must add signal conditioning elements to reduce the potential transients before they reach the Analog Buses.

High Energy Sources

The Analog Buses and the optional internal DMM are designed to handle inputs up to their rated currents or their rated powers, whichever is less. Under certain fault conditions, high energy sources could provide substantially more current or power than the instrument can handle. It is important to provide external current limiting, such as fuses, if the inputs are connected to high- energy sources.

CAUTION

34980A User’s Guide 29

Install current limiting devices between high energy sources and the module inputs.

2 Features and Functions

Temperature Measurement Configuration

This section contains information to help you configure the instrument for making temperature measurements. The table below shows the thermocouple, RTD, and thermistor types for which the instrument supports direct measurements.

Temperature transducers supported

Thermocouple Types

B, E, J, K, N, R, S, T R

* Using ITS-90 software conversions.

† Using IPTS-68 software conversions.

Measurement Units

• The instrument can report temperature measurements in °C (Celsius), °F (Fahrenheit), or K (Kelvins). You can mix temperature units on different channels within the instrument and on the same module.

• The

• Setting the Mx+B measurement label to °C, °F, or K has no affect on

• The instrument selects Celsius when the probe type is changed and

CONFigure and MEASure? commands automatically select °C.

the temperature measurement units currently selected.

after a Factory Reset ( (SYSTem:PRESet command) or Card Reset (SYSTem:CPON command) does not change the units setting.

RTD Types Thermistor Types

= 49Ω to 2.1 kΩ

α = 0.00385 (DIN/IEC 751) α = 0.00391

*RST command). An Instrument Preset

†

2.2 kΩ, 5 kΩ, 10 kΩ

(YSI 44000 Series)

Front Panel Operation: DMM or Channel (Configure) > TEMPERATURE > UNITS

Remote Interface Operation: UNIT:TEMP {C|F|K}[,(@<ch_list>)]

30 34980A User’s Guide

Thermocouple Measurements

• The instrument supports the following thermocouple types: B, E, J, K, N, R, S, and T using ITS- 90 software conversions. The default is a

J- Type thermocouple.

• Thermocouple measurements require a reference junction temperature. For the reference junction temperature, you can use an internal measurement on the module (34921A only), an external thermistor or RTD measurement, or a known fixed junction temperature.

• The internal reference junction source is valid only on channels 1

through 40 on the 34921A with the 34921T terminal block installed.

• If you select an external reference, the instrument makes

thermocouple measurements relative to a previously- stored RTD or thermistor measurement stored in a reference register. To store a reference temperature, first configure a multiplexer channel for an RTD or thermistor measurement. Then assign the measurement from that channel as the external reference. When you initiate a measurement on an external reference channel, the acquired temperature is stored in volatile memory in the reference register. Subsequent thermocouple measurements use the stored temperature as their reference. The temperature remains in memory until you measure a subsequent external reference value in the reference register or remove the mainframe power.

Features and Functions 2

• If you select a fixed reference temperature, specify a value between

- 20 °C and +80 °C (always specify the temperature in °C regardless of the temperature units currently selected).

• The accuracy of the measurement is highly dependent upon the thermocouple connections and the type of reference junction used. Use a fixed temperature reference for the highest accuracy measurements (you must maintain the known junction temperature). The internal isothermal block reference (34921A only) requires no external wiring but provides lower accuracy measurements than a fixed reference.

• The thermocouple check feature allows you to verify that your thermocouples are properly connected for measurements. If you enable this feature, the instrument measures the channel resistance after each thermocouple measurement to ensure a proper connection. If an open connection is detected (greater than 5 kΩ on the 10 kΩ range), the instrument reports an overload condition for that channel (or displays “OPEN T/C” on the front panel).

34980A User’s Guide 31

2 Features and Functions

Front Panel Operation: To select the thermocouple function on the active

channel, choose the following items.

DMM or Channel (Configure) > TEMPERATURE > PROBE TYPE > THERMOCOUPLE

Then, use the knob to select the thermocouple type from the list.

THERMOCOUPLE TYPE > B|E|J|K|N|R|S|T

If desired, you can enable the thermocouple check feature on the active channel (opens are reported as “OPEN T/C”).

T/C CHECK > OFF|ON

To select the reference junction source for the active channel, choose one of the following items.

REFERENCE > FIXED|EXT|INT

For an external reference, configure an RTD or thermistor as the external reference channel.

Channel (Configure) > TEMPERATURE > PROBE TYPE > RTD > . . . USE AS EXT REF?

Remote Interface Operation: You can use the CONFigure or MEASure?

command to select the probe type and thermocouple type. For example, the following command configures channel 3001 for a J- type thermocouple measurement.

CONF:TEMP TC,J,(@3001)

You can also use the SENSe command to select the probe type and thermocouple type. For example, the following command configures channel 2003 for a J- type thermocouple measurement.

SENS:TEMP:TRAN:TC:TYPE J,(@2003)

The following commands use the SENSe command to set a fixed reference junction temperature of 40 degrees (always in °C) on channel 2003.

SENS:TEMP:TRAN:TC:RJUN:TYPE,(@2003) SENS:TEMP:TRAN:TC:RJUN 40,(@2003)

The following command enables the thermocouple check feature on the specified channel (opens are reported as “+9.90000000E+37”).

SENS:TEMP:TRAN:TC:CHECK ON,(@2003)

The following commands select the fixed reference junction source and set the junction temperature to 20 °C on the specified channel.

TEMP:TRAN:TC:RJUN:TYPE FIX, (@2003) TEMP:TRAN:TC:RJUN 20, (@2003)

32 34980A User’s Guide

RTD Measurements

• The instrument supports RTDs with α = 0.00385 (DIN/IEC 751) using ITS- 90 software conversions or α = 0.00391 using IPTS- 68 software conversions. The default is α = 0.00385.

Features and Functions 2

• The resistance of an RTD is nominal at 0 °C and is referred to as R

The instrument can measure RTDs with R0 values from 49Ω to 2.1 kΩ.

• You can measure RTDs using a 2- wire or 4- wire measurement method. The 4- wire method provides the most accurate way to measure small resistances. Connection lead resistance is automatically removed using the 4-wire method.

• For 4- wire RTD measurements, the instrument automatically pairs channel n in Bank 1 with channel n+20 in Bank 2 (34921A, 34923A) or n+35 (34922A, 34924A) to provide the source and sense connections. For example, make the source connections to the HI and LO terminals on channel 2 in Bank 1 and the sense connections to the HI and LO terminals on channel 22 (or 37) in Bank 2.

Front Panel Operation: To select the 2-wire or 4-wire RTD function for the

active channel, choose the following items.

DMM or Channel (Configure) > TEMPERATURE > PROBE TYPE > RTD|4W RTD

To select the RTD type (α = 0.00385 or 0.00391) for the active channel, choose the following item.

RTD TYPE > 0.00391|0.00385

To select the nominal resistance (R0) for the active channel, choose the following item.

RO > 100 OHM

Remote Interface Operation: You can use the CONFigure or MEASure?

command to select the probe type and RTD type. For example, the following command configures channel 3001 for 2- wire measurements of an RTD with α = 0.00385 (use “85” to specify α = 0.00385 or “91” to specify α = 0.00391).

CONF:TEMP RTD,85,(@3001)

You can also use the SENSe command to select the probe type, RTD type, and nominal resistance. For example, the following command configures channel 1003 for 4- wire measurements of an RTD with α = 0.00391 (channel 1003 is automatically paired with channel 1023 for the 4-wire measurement).

SENS:TEMP:TRAN:FRTD:TYPE 91,(@1003)

34980A User’s Guide 33

2 Features and Functions

The following command sets the nominal resistance (R0) to 1000Ω on channel 1003.

SENS:TEMP:TRAN:FRTD:RES 1000,(@1003)

Thermistor Measurements

The instrument supports 2.2 kΩ (YSI Series 44004), 5 kΩ (YSI Series 44007), and 10 k

Front Panel Operation: To select the thermistor function for the active

channel, choose the following items.

DMM or Channel (Configure) > TEMPERATURE > PROBE TYPE > THERMISTOR

To select the thermistor type for the active channel, choose from the following items.

THERMISTOR TYPE > 10K|5K|2.2K

Ω (YSI Series 44006) thermistors.

Remote Interface Operation: You can use the CONFigure or MEASure?

command to select the probe type and thermistor type. For example, the following command configures channel 3001 for measurements of a 5 kΩ thermistor:

CONF:TEMP THER,5000,(@3001)

You can also use the SENSe command to select the probe type and thermistor type. For example, the following command configures channel 1003 for measurements of a 10 k

SENS:TEMP:TRAN:THERM:TYPE 10000,(@1003)

Ω thermistor:

34 34980A User’s Guide

Voltage Measurement Configuration

This section contains information to help you configure the instrument for making voltage measurements. The instrument can measure dc and true RMS ac- coupled voltages on the measurement ranges shown below.

100 mV 1 V 10 V 100 V 300 V Autorange

DC Input Resistance

Normally, the instrument’s input resistance is fixed at 10 MΩ for all dc voltage ranges to minimize noise pickup. To reduce the effects of measurement loading errors, you can set the input resistance to greater than 10 G

Applies to dc voltage measurements only.

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

Features and Functions 2

DC input resistance

Input Resistance Setting

Input Resistance: Auto OFF Input Resistance: Auto ON

• The

CONFigure and MEASure? commands automatically select AUTO OFF

Input Resistance for: 100 mV, 1 V, 10 V ranges

10 MΩ > 10 GΩ

Input Resistance for: 100 V, 300 V ranges

10 MΩ 10 MΩ

(fixed at 10 MΩ for all ranges).

• The instrument selects 10 M ranges) after a Factory Reset (

Ω (fixed input resistance on all dc voltage

*RST command). An Instrument Preset

(SYSTem:PRESet command) or Card Reset (SYSTem:CPON command) does not change the input resistance setting.

Front Panel Operation: DMM or Channel (Configure) > INPUT RESISTANCE

Remote Interface Operation: You can enable or disable the automatic

input resistance mode on the specified channels or the internal DMM. With AUTO OFF (default), the input resistance is fixed at 10 M

Ω for all

ranges. With AUTO ON, the input resistance is set to >10 GΩ for the three lowest dc voltage ranges.

[SENSe:]<function>:IMPedance:AUTO {OFF|ON} [,(@<ch_list>)]

If you omit the optional <ch_list> parameter, the command applies to the internal DMM.

34980A User’s Guide 35

2 Features and Functions

AC Low Frequency Filter

The instrument uses three different ac filters which enable you to either optimize low- frequency accuracy or achieve faster ac settling times. The instrument selects the slow (3 Hz), medium (20 Hz), or fast (300 Hz) filter based on the input frequency that you specify for the selected channels or the internal DMM.

Applies to ac voltage and ac current measurements only.

AC low frequency filter

Input Frequency Default Settling Delay Minimum Settling Delay

3 Hz to 300 kHz (Slow) 20 Hz to 300 kHz (Medium) 200 Hz to 300 kHz (Fast)

• The

CONFigure and MEASure? commands automatically select the 20 Hz

7 seconds / reading 1 second / reading

0.12 seconds / reading

1.5 seconds 200 ms 20 ms

(medium) filter.

• The instrument selects the default 20 Hz (medium) filter after a Factory Reset (

*RST command). An Instrument Preset (SYSTem:PRESet command) or

Card Reset (SYSTem:CPON command) does not change the setting.

Front Panel Operation: DMM or Channel (Configure) > AC FILTER

Remote Interface Operation: Specify the lowest frequency expected in

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

[SENSe:]VOLTage:AC:BANDwidth {3|20|200} [,(@<ch_list>)]

If you omit the optional <ch_list> parameter, the command applies to the internal DMM.

36 34980A User’s Guide

Resistance Measurement Configuration

This section contains information to help you configure the instrument for making resistance measurements. Use the 2- wire method for ease of wiring and higher density or use the 4- wire method for improved measurement accuracy. The measurement ranges shown below.

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

Offset Compensation

Offset compensation removes the effects of any dc voltages in the circuit being measured. The technique involves taking the difference between two resistance measurements on the specified channels, one with the current source turned on and one with the current source turned off.

Applies only to 2- wire and 4- wire resistance measurements on the

Ω

, 1 kΩ, and 10 kΩ ranges.

100

Features and Functions 2

• Four- wire measurements are not allowed on the multiplexer modules configured for the 1- wire (single ended) mode (see page 27).

• For 4-wire resistance measurements, the instrument automatically pairs channel n in Bank 1 with channel n+20 in Bank 2 (34921A, 34923A, 34925A) or n+35 (34922A, 34924A) to provide the source and sense connections. For example, make the source connections to the HI and LO terminals on channel 2 in Bank 1 and the sense connections to the HI and LO terminals on channel 22 (or 37) in Bank 2.

• The

• The instrument disables offset compensation after a Factory Reset

CONFigure and MEASure? commands automatically disable offset

compensation.

*RST command). An Instrument Preset (SYSTem:PRESet command) or

( Card Reset (SYSTem:CPON command) does not change the setting.

Front Panel Operation: DMM or Channel (Configure) > OFFSET COMP

Remote Interface Operation:

[SENSe:]FRESistance:OCOMpensated {OFF|ON} [,(@<ch_list>)] [SENSe:]RESistance:OCOMpensated {OFF|ON} [,(@<ch_list>)]

If you omit the optional <ch_list> parameter, the command applies to the internal DMM. For 4-wire measurements, specify the paired channel in Bank 1 (source) as the <ch_list> channel (channels in Bank 2 are not allowed in the <ch_list>).

34980A User’s Guide 37

2 Features and Functions

Current Measurement Configuration

This section contains information to help you configure the instrument for making current measurements on the 34921A multiplexer module. The module has four fused channels for direct dc and ac current measurements on the ranges shown below.

10 mA 100 mA 1 A Autorange

Current measurements are allowed only on channels 41 through 44 on the 34921A module.

AC Low Frequency Filter

Applies to ac current and ac voltage measurements only.

AC low frequency filter

Input Frequency Default Settling Delay Minimum Settling Delay

3 Hz to 300 kHz (Slow) 20 Hz to 300 kHz (Medium) 200 Hz to 300 kHz (Fast)

• The

CONFigure and MEASure? commands automatically select the 20 Hz

7 seconds / reading 1 second / reading

0.12 seconds / reading

1.5 seconds 200 ms 20 ms

(medium) filter.

• The instrument selects the default 20 Hz (medium) filter after a Factory Reset ( Card Reset (

*RST command). An Instrument Preset (SYSTem:PRESet command) or

SYSTem:CPON command) does not change the setting.

Front Panel Operation: DMM or Channel (Configure) > AC FILTER

Remote Interface Operation: Specify the lowest frequency expected in

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

[SENSe:]CURRent:AC:BANDwidth {3|20|200} [,(@<ch_list>)]

If you omit the optional <ch_list> parameter, the command applies to the internal DMM.

38 34980A User’s Guide

Frequency Measurement Configuration

This section contains information to help you configure the instrument for making frequency measurements.

Low Frequency Timeout

The instrument uses three different timeout ranges for frequency measurements. The instrument selects the slow (3 Hz), medium (20 Hz), or fast (300 Hz) filter based on the input frequency that you specify with this command for the selected channels.

Applies to frequency measurements only.

Low frequency timeout

Input Frequency Timeout

Features and Functions 2

3 Hz to 300 kHz (Slow) 20 Hz to 300 kHz (Medium) 200 Hz to 300 kHz (Fast)

• The

CONFigure and MEASure? commands automatically select the 20 Hz

1 second 100 ms 10 ms

(medium) filter.

• The instrument selects the default 20 Hz (medium) filter after a Factory Reset (

*RST command). An Instrument Preset (SYSTem:PRESet command) or

Card Reset (SYSTem:CPON command) does not change the setting.

Front Panel Operation: DMM or Channel (Configure) > AC FILTER

Remote Interface Operation: Specify the lowest frequency expected in the

input signal on the specified channels. The instrument selects the appropriate timeout based on the frequency you specify (see table above).

[SENSe:]FREQuency:RANGe:LOWer {3|20|200} [,(@<ch_list>)]

If you omit the optional <ch_list> parameter, the command applies to the internal DMM.

34980A User’s Guide 39

2 Features and Functions

Mx+B Scaling

The scaling function allows you to apply a gain and offset to readings during a scan or while making measurements in the stand- alone DMM mode. In addition to setting the gain (“M”) and offset (“B”) values, you can also specify a custom measurement label for your scaled readings (RPM, PSI, etc.). You can apply scaling to any multiplexer channels and for any measurement function. Scaling is not allowed with any of the channels on the digital modules.

• Scaling is applied using the following equation:

• You must configure the channel (function, transducer type, etc.) before

Scaled Reading = (Gain x Measurement) + Offset

applying any scaling values. If you change the measurement configuration, scaling is turned off on that channel and the gain and offset values are reset (M=1 and B=0). Scaling is also turned off when you change the temperature probe type, temperature units, or disable the internal DMM.

• If you plan to use scaling on a channel which will also use alarms, be sure to configure the scaling values first. If you attempt to assign the alarm limits first, the instrument will turn off alarms and clear the limit values when you enable scaling on that channel. If you specify a custom measurement label with scaling, it is automatically used when alarms are logged on that channel.

• If you redefine the scan list, scaling is turned off on those channels but the gain and offset values are not cleared. If you decide to add a channel back to the scan list (without changing the function), the original gain and offset values are restored and scaling is turned back on. This makes it easy to temporarily remove a channel from the scan list without entering the scaling values again.

• You can specify a custom label with up to three characters. You can use letters (A- Z), numbers (0- 9), an underscore ( _ ), or the “#” character which displays a degree symbol ( ° ) on the front panel (displayed as a “#” in an output string from the remote interface). The first character must be a letter or the “#” character (the “#” character is allowed only as the leftmost character in the label). The remaining two characters can be letters, numbers, or an underscore. Blank spaces are not allowed.

• The maximum value allowed for the gain and offset is ±1E+15.

40 34980A User’s Guide

Features and Functions 2

• The CONFigure and MEASure? commands automatically set the gain (“M”) to 1 and offset (“B”) to 0.

• A Factory Reset (

*RST command) turns off scaling and clears the

scaling values on all channels. An Instrument Preset (SYSTem:PRESet command) does not clear the scaling values and does not turn off scaling.

Front Panel Operation:

DMM or Channel (Configure) > SCALING > GAIN|OFFSET|UNITS

To define the label on the selected channel, press the arrow keys to move the cursor to a specific position and then turn the knob to select the desired letter or number. To clear the label on the selected channel, change each character to “ ^ ” (starting with the rightmost character) and then press the left arrow key to move to the next character.

Remote Interface Operation: Use the following commands to set the gain,

offset, and custom measurement label.

CALC:SCALE:GAIN 1.2,(@1003) CALC:SCALE:OFFSET 10,(@1003) CALC:SCALE:UNIT 'PSI',(@1003)

After setting the gain and offset values, send the following command to enable the scaling function on the specified channel.

CALC:SCALE:STATE ON,(@1003)

34980A User’s Guide 41

2 Features and Functions

Scanning

The instrument allows you to combine a DMM (either internal or external) with multiplexer channels to create a scan. During a scan, the instrument connects the DMM to the configured multiplexer channels one at a time and makes a measurement on each channel.

Any channel that can be “read” by the instrument can also be included in a scan. This includes any combination of temperature, voltage, resistance, current, frequency, or period measurements on multiplexer channels. A scan can also include a read of a digital channel or a read of the totalizer count on the digital modules. Scanning is allowed with the following modules:

• 34921A through 34925A Multiplexer Modules

• 34950A Digital I/O Module (digital input and counter channels only)

• 34952A Multifunction Module (digital input and totalizer channels only)

Automated scanning is not allowed with the other switching modules. In addition, a scan cannot include a write to a digital channel or a voltage output from a DAC channel. You can, however, write your own program to manually create a “scan” to include these operations.

Rules for Scanning

• Before you can initiate a scan, you must set up a scan list to include all desired multiplexer or digital channels. Channels which are not in the scan list are skipped during the scan. By default, the instrument scans the list of channels in ascending order from slot 1 through slot 8 (channels are reordered as needed). If your application requires non- ordered scanning of the channels in the present scan list, see

“Non- Sequential Scanning” on page 57. Measurements are taken only

during a scan and only on those channels which are included in the scan list.

• You can store at least 500,000 readings in memory and all readings are automatically time stamped. If memory overflows, a status register bit is set and new readings will overwrite the first (oldest) readings stored. The most recent readings are always preserved. You can read the contents of memory at any time, even during a scan. Reading memory is not cleared when you read it.

• Each time you start a new scan, the instrument clears all readings (including alarm data) stored in reading memory from the previous scan. Therefore, the contents of memory are always from the most recent scan.

42 34980A User’s Guide

Features and Functions 2

• The Analog Bus relays are automatically opened and closed as required during the scan to connect to the internal DMM for the measurement. For example, all 2- wire measurements use the ABus1 (MEAS) relays; for 4- wire measurements, the ABus2 (SENS) relays are used in addition to the ABus1 relays.

• When the scan is initiated, the instrument will open all channels in banks that contain one or more channels in the scan list.

• In order to guarantee that no signals are connected to the Analog Buses prior to the scan, the instrument will open all

ABus1 relays (applies to all banks in all slots). In banks that contain channels in the scan list, the instrument will also open all ABus2 relays (regardless of whether 4- wire measurements are involved). If no channels configured for 4- wire measurements are included in the scan list, the state of the ABus2 relays in the non- scanned banks is not altered.

• The state of the ABus3 and ABus4 relays is not

altered and these relays

remain available for use during the scan. However, be sure to use CAUTION when closing these relays on banks involved in the scan. While the scan is running, any signals present on ABus3 and/or ABus4 will be joined with the scanned measurement on ABus1 and ABus2.

• While the scan is running, the instrument prevents use of all channels

in banks that contain one or more channels in the specified scan list (these channels are dedicated to the scan). In addition, the instrument prevents use of all ABus1 and ABus2 relays on banks containing channels in the scan list. If one or more channels configured for 4- wire measurements are included in the scan list, then the rules for ABus2 relay operations are extended to the non- scanned banks as well.

• If the ABus1 relay used for current measurements (channel 931 on

34921A only) is not closed prior to the initiation of the scan, the four current channels (channels 41 through 44) are not affected by the scan. However, if the ABus1 relay is closed, the instrument will open the ABus1 relay as well as the four associated current channels in a make- before- break fashion.

• When you add a digital read (digital modules) to a scan list, the

corresponding channel is dedicated to the scan. The instrument issues a Card Reset to make that channel an input channel (the other channel is not affected).

• While the scan is running, you can perform low- level control operations

on any channels on the digital modules that are not in the scan. For example, you can output a DAC voltage or write to a digital channel (even if the totalizer is part of the scan list). However, you cannot change any parameters that affect the scan (channel configuration, scan interval, Card Reset, etc.) while a scan is running.

• If a scan includes a read of the totalizer, the count is reset each time it

is read during the scan only when the totalizer reset mode is enabled.

34980A User’s Guide 43

2 Features and Functions

• At the end of the scan, the last channel that was scanned will be

• If you abort a scan that is running, the instrument will terminate any

• You can use either the internal DMM or an external instrument to make

• The Monitor mode is automatically enabled on all channels that are

• The present scan list is stored in volatile memory and will be lost when

opened (as well as any Analog Bus relays used during the scan). Any channels that were opened during the scan will remain open at the completion of the scan.

reading in progress (readings are not cleared from memory). If a scan is in progress when the command is received, the scan will not be completed and you cannot resume the scan from where it left off. Note that if you initiate a new scan, all readings are cleared from memory.

measurements of your configured channels. However, the 34980A allows only one scan list at a time; you cannot scan some channels using the internal DMM and others using an external instrument. Readings are stored in 34980A memory only when the internal DMM is used.

part of the active scan list (see “Monitor Mode” on page 60).

power is turned off or after a Factory Reset (

*RST command).

Adding Channels to the Scan List

Before you can initiate a scan, you must set up a scan list to include all desired multiplexer or digital channels. Channels which are not in the scan list are skipped during the scan. By default, the instrument scans the list of channels in ascending order from slot 1 through slot 8 (channels are reordered as needed).

To Build a Scan List From the Front Panel

• To add the active channel to the scan list, press Channel (Configure).

Then select the function, range, resolution, and other parameters for this channel. Then add the channel to the scan list by selecting:

SCAN THIS CHANNEL? > YES

• To remove the active channel from the scan list, select:

SCAN THIS CHANNEL? > NO

• To remove all channels from the scan list, select:

Scan (Configure) > CLEAR SCAN LIST? > YES

44 34980A User’s Guide

Features and Functions 2

• To initiate a scan and store all readings in memory, press

Scan (Measure). Each time you initiate a new scan, the instrument clears all previously stored readings. If you have not defined a scan list, Scan (Measure) performs an internal DMM scan independent of any channels.

• To stop a scan in progress, press and hold Scan (Measure).

To Build a Scan List From the Remote Interface

• Use the ROUTe:SCAN command to define the list of channels in the scan

list. To determine what channels are currently in the scan list, use the

ROUTe:SCAN? query command.

• To add channels to the present scan list, use the

ROUTe:SCAN:ADD

command. To remove channels from the present scan list, use the

ROUTe:SCAN:REMove command.

• To remove all channels from the scan list, send “

• To initiate a scan, use the

INITiate or READ? command.

ROUT:SCAN (@)”.

Measurements are stored in memory. Each time you initiate a new scan, the instrument will clear the previous set of readings from memory.

• To stop a scan in progress, use the

ABORt command.

34980A User’s Guide 45

2 Features and Functions

Scan Trigger Source

You can configure the event or action that controls the onset of each sweep through the scan list (a sweep is one pass through the scan list):

• You can set the instrument’s internal timer to automatically scan at a

• You can manually control a scan by repeatedly pressing the

• You can start a scan by sending a software command from the remote

• You can start a scan when an external TTL trigger pulse is received.

Interval Scanning

In this configuration, you control the frequency of scan sweeps by selecting a wait period from the start of one trigger to the start of the next trigger (called the trigger- to- trigger interval). If the scan interval is less than the time required to measure all channels in the scan list, the instrument will scan continuously, as fast as possible (no error is generated).

specific interval. You can also program a time delay between channels in the scan list (see “Channel Delay” on page 53).

Scan (Measure) key from the front panel.

interface (

MEASure? or INITiate command).

Trigger 1

Sweep 1

Sweep 2

Sweep n

Trigger 2

. . .

Trigger Timer

(0 to 359,999 seconds)

Trigger-to-trigger interval

• You can set the scan interval to any value between 0 seconds and

99:59:59 hours (359,999 seconds), with 1 ms resolution.

• Once you have initiated the scan, the instrument will continue scanning

until you stop it or until the trigger count is reached. See “Trigger

Count” on page 49 for more information.

• Mx+B scaling and alarm limits are applied to measurements during a

scan and all data is stored in non- volatile memory.

• The

CONFigure and MEASure? commands automatically set the scan

interval to immediate (0 seconds) and the scan count to 1 sweep.

46 34980A User’s Guide

Features and Functions 2

• The instrument sets the scan interval to immediate (0 seconds) after a

Factory Reset (*RST command). An Instrument Preset (SYSTem:PRESet command) or Card Reset (

SYSTem:CPON command) does not change

the setting.

Front Panel Operation: Scan (Configure) > INTERVAL > SCAN INTERVAL

To initiate the scan and store all readings in memory, press the Scan (Measure) key. Between scan sweeps, “WAITING FOR TRIG” will be displayed on the front panel.

Note: To stop a scan, press and hold the Scan (Measure) key.

Remote Interface Operation: The following program segment configures the

instrument for an interval scan.

TRIG:SOURCE TIMER TRIG:TIMER 5 TRIG:COUNT 2 INIT

Select interval time mode Set the scan interval to 5 seconds Sweep the scan list 2 times Initiate the scan

Note: To stop a scan, press and hold the Scan (Measure) key.

Manual Scanning

In this configuration, the instrument waits for either a front- panel key press or a remote interface command before sweeping through the scan list.

• All readings from the scan are stored in non-volatile memory.

Readings accumulate in memory until the scan is terminated (until the trigger count is reached or until you abort the scan).

• You can specify a trigger count which sets the number of front- panel

key presses or scan trigger commands that will be accepted before terminating the scan. See “Trigger Count” on page 49 for more information.

• Mx+B scaling and alarm limits are applied to measurements during a

manual scanning operation and all data is stored in non- volatile memory.

Front Panel Operation: Scan (Configure) > INTERVAL > MANUAL

To initiate the scan and store all readings in memory, press the Scan (Measure) key.

Note: To stop a scan, press and hold the Scan (Measure) key.

34980A User’s Guide 47

2 Features and Functions

Remote Interface Operation: The following program segment configures the

instrument for a manual scanning operation.

TRIG:SOURCE BUS TRIG:COUNT 2 INIT

Then, send the The

*TRG command will not be accepted unless the internal DMM is in

*TRG (trigger) command to begin each scan sweep.

Select bus (manual) mode Sweep the scan list 2 times Initiate the scan

the “wait- for-trigger” state.

Note: To stop a scan, press and hold the Scan (Measure) key.

External Scanning

In this configuration, the instrument sweeps through the scan list once each time a low- going TTL pulse is received on the rear- panel Ext Trig Input line (pin 6).

Ext Trig Input (Pin 6)

Gnd (Pin 9)

5 V

0 V

Input

> 1 µs

Ext Trig Input connector (as viewed from rear of instrument)

• You can specify a scan count which sets the number of external pulses

the instrument will accept before terminating the scan. See “Trigger

Count” on page 49 for more information.

• If the instrument receives an external trigger before it is ready to

accept one, it will buffer one trigger and then ignore any additional triggers received (no error is generated).

• All readings from the scan are stored in non-volatile memory.

Readings accumulate in memory until the scan is terminated (until the scan count is reached or until you abort the scan).

• Mx+B scaling and alarm limits are applied to measurements during the

scan and all data is stored in non- volatile memory.

48 34980A User’s Guide

Features and Functions 2

Front Panel Operation: Scan (Configure) > INTERVAL > EXTERNAL

To initiate the scan and store all readings in memory, press the Scan (Measure) key. Between scan sweeps, “WAITING FOR TRIG” will be displayed on the front panel. When a TTL pulse is received, the scan starts and readings are stored in memory.

Note: To stop a scan, press and hold the Scan (Measure) key.

Remote Interface Operation: The following program segment configures the

instrument for an external scan.

Note: To stop a scan, press and hold the Scan (Measure) key.

Tri g ge r Co u nt

You can specify the number of triggers that will be accepted by the internal DMM before returning to the “idle” state. The trigger count applies to both scanning and stand- alone DMM measurements (with no scan list).

• Select a trigger count between 1 and 500,000 triggers, or continuous.

• You can store at least 500,000 readings in memory and all readings are

• You can specify a trigger count in conjunction with a sample count and

TRIG:SOURCE EXT TRIG:COUNT 2 INIT

Select external mode Sweep the scan list 2 times Initiate the scan

automatically time stamped. If memory overflows, the new readings will overwrite the first (oldest) readings stored; the most recent readings are always preserved.

a sweep count. The three parameters operate independent of one another, and the total number of readings returned will be the product of the three parameters.

• The

CONFigure and MEASure? commands automatically set the scan

trigger count to 1.

• The instrument sets the scan trigger count to 1 after a Factory Reset

*RST command). An Instrument Preset (SYSTem:PRESet command) or

( Card Reset (SYSTem:CPON command) does not change the setting.

Front Panel Operation: Scan (Configure) > SCAN TRIGGER > COUNTED|INFINITE

Remote Interface Operation: TRIGger:COUNt

To configure a continuous scan, send TRIG:COUNT INFINITY.

34980A User’s Guide 49

2 Features and Functions

Sweep Count

The sweep count sets the number of sweeps per trigger event during a scan (a sweep is one pass through the scan list). The front- panel sample annunciator (“*”) turns on during each measurement.

Sweep 1Trigger

Sweep 2

Sweep n

Trigger

. . .

Sweep Count

(1 to 500,000 sweeps)

Sweep count

• The sweep count is valid only while scanning. If no channels have been

assigned to the scan list, the specified sweep count is ignored (no error is generated).

• You can specify a sweep count in conjunction with a trigger count and

a sample count. The three parameters operate independent of one another, and the total number of readings returned will be the product of the three parameters.

• You can store at least 500,000 readings in memory and all readings are

automatically time stamped. If memory overflows, the new readings will overwrite the first (oldest) readings stored; the most recent readings are always preserved.

• The

CONFigure and MEASure? commands automatically set the sweep

count to 1 sweep.

• The instrument sets the sweep count to 1 after a Factory Reset

*RST command). An Instrument Preset (SYSTem:PRESet command) or

( Card Reset (

SYSTem:CPON command) does not change the setting.

Front Panel Operation: Scan (Configure) > SWEEP COUNT

Remote Interface Operation: SWEep:COUNt

50 34980A User’s Guide

Sample Count

The sample count sets the number of auto- triggered samples the internal DMM will take per channel per trigger. The sample count applies to both scanning and stand- alone DMM measurements (with no scan list). The front- panel sample annunciator (“ *”) turns on during each measurement.

Trigger Trigger

Sample count for Stand-Alone DMM Mode

Features and Functions 2

Sample Count

(1 to 500,000 samples)

Sweep Count

Sweep 1Trigger Sweep 2

Ch 1 Ch 3 Ch 4Ch 2 Ch 5 Ch 6

Sample Count

(1 to 500,000 samples)

Sample count for Scanning Mode

. . .

Sweep n

Trigger

34980A User’s Guide 51

2 Features and Functions

• For scanning, the specified sample count sets the number of readings

• You can specify a sample count in conjunction with a trigger count and

• You can store at least 500,000 readings in memory and all readings are

per channel (same for all channels in the scan list). If no channels have been assigned to the scan list, the sample count sets the number of readings per trigger for the internal DMM.

a sweep count. The three parameters operate independent of one another, and the total number of readings returned will be the product of the three parameters.

automatically time stamped. If memory overflows, the new readings will overwrite the first (oldest) readings stored; the most recent readings are always preserved.

• The

CONFigure and MEASure? commands automatically set the sample

count to 1.

• The instrument sets the sample count to 1 after a Factory Reset

*RST command). An Instrument Preset (SYSTem:PRESet command) or

( Card Reset (

SYSTem:CPON command) does not change the setting.

Front Panel Operation: Scan (Configure) > SAMPLE COUNT

Remote Interface Operation: SAMPle:COUNt

52 34980A User’s Guide

Channel Delay

You can control the pacing of a scan sweep by inserting a delay between multiplexer channels in the scan list (useful for high- impedance or high- capacitance circuits). The delay is inserted between the relay closure and the actual measurement on the channel, in addition to any delay that will implicitly occur due to relay settling time. The programmed channel delay overrides the default channel delay that the instrument automatically adds to each channel.

Features and Functions 2

Scan List

Ch 1 Ch 3 Ch 4Ch 2 Ch 5 Ch 6

Channel Delay

(0 to 60 seconds)

Channel delay

• You can set the channel delay to any value between 0 seconds and

60 seconds, with 1 ms resolution. You can select a different delay for each channel. The default channel delay is automatic; the instrument determines the delay based on function, range, integration time, and ac filter setting (see “Automatic Channel Delays” on page 54).

• You can select a unique delay for every channel on the module.

• The channel delay is valid only while scanning. If no channels have

been assigned to the scan list, the specified channel delay is ignored (no error is generated).

34980A User’s Guide 53

2 Features and Functions

• To ensure you are getting the most accurate measurements possible,

use care when setting the channel delay less than the default value (automatic). The default channel delay is designed to optimize parameters, such as settling time, for the most accurate measurements.

• The

CONFigure and MEASure? commands set the channel delay to

automatic. A Factory Reset (*RST command) also sets the channel delay to automatic.

Front Panel Operation: Channel (Configure) > CHANNEL DELAY > TIME

Once you have added the specified channel to the scan list, the channel delay choice will be visible in the menu.

Interface Operation: The following command add a 2- second channel delay

to the specified channels.

ROUT:CHAN:DELAY 2,(@1003,1013)

Automatic Channel Delays

If you do not specify a channel delay, the instrument selects a delay for you. The delay is determined by the delay based on function, range, integration time, and ac filter setting.

DC Voltage, Thermocouple, DC Current (for all ranges):

Integration Time Channel Delay

PLC > 1 PLC ≤ 1

2.0 ms

1.0 ms

Resistance, RTD, Thermistor (2- and 4-wire):

Channel Delay

Range

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

(for PLC > 1) Range

2.0 ms

2.0 ms 25 ms 30 ms 200 ms 200 ms

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

Channel Delay (for PLC ≤ 1)

1.0 ms

1.0 ms 20 ms 25 ms 200 ms 200 ms

54 34980A User’s Guide

AC Voltage, AC Current (for all ranges):

AC Filter Channel Delay

Features and Functions 2

Slow (3 Hz) Medium (20 Hz) Fast (200 Hz)

7.0 seconds

1.0 second 120 ms

Frequency, Period:

AC Filter Channel Delay

Slow (3 Hz) Medium (20 Hz) Fast (200 Hz)

600 ms 300 ms 100 ms

Digital Input, Totalize:

Channel Delay

0 seconds

Front Panel Operation: Channel (Configure) > CHANNEL DELAY > AUTO

Once you have added the specified channel to the scan list, the channel delay choice will be visible in the menu.

Interface Operation: The following command enables an automatic channel

delay on the specified channels.

ROUT:CHAN:DELAY:AUTO ON,(@1003,1013)

Selecting a specific channel delay using the ROUTe:CHANnel:DELay command (see “Channel Delay” on page 53) disables the automatic channel delay.

34980A User’s Guide 55

2 Features and Functions

Reading Format

During a scan, the instrument automatically adds a time stamp to all readings and stores them in memory. Each reading is stored with measurement units, time stamp, channel number, and alarm status information. From the remote interface, you can specify which information you want returned with the readings (from the front panel, all of the information is available for viewing). The examples below show a reading in relative and absolute format with all fields enabled.

Relative Format (Default):

2.61950000E+01 C,000000000.017,1003,2

1 2 43

12Reading with units (26.195 °C)

Time since start of scan (17 ms)

34Channel number

Alarm limit threshold crossed (0 = No Alarm, 1 = LO, 2 = HI)

Absolute Format:

2.61950000E+01 C,2004,11,21,15,30,23.000,1003,2

1 3 542

Reading with units (26.195 °C)

Date (November 21, 2004)

Time of day (3:30:23.000 PM)

45Channel number

Alarm limit threshold crossed (0 = No Alarm, 1 = LO, 2 = HI)

• The reading format applies to all readings being removed from the

instrument from a scan; you cannot set the format on a per- channel basis.

• The

CONFigure and MEASure? commands automatically turn off the

units, time, channel, and alarm information.

• The format settings are stored in volatile memory and will be lost when

power is turned off or after a Factory Reset (

56 34980A User’s Guide

*RST command).

Remote Interface Operation: Use the following commands to select the

reading format.

FORMat:READing:ALARm ON FORMat:READing:CHANnel ON FORMat:READing:TIME ON FORMat:READing:TIME:TYPE {ABSolute|RELative} FORMat:READing:UNIT ON

Non-Sequential Scanning

By default, the instrument scans the list of channels in ascending order from slot 1 through slot 8 (channels are reordered as needed). If your application requires non- ordered scanning of the channels in the present scan list, you can use the non- sequential scanning mode.

This feature is available from the remote interface only.

• The scanning mode applies to the entire mainframe and cannot be

selectively used on individual modules.

Features and Functions 2

• When sequential scanning is enabled (default), the channels in the scan

list are placed in ascending order from slot 1 through slot 8. Duplicate channels are not allowed. For example, (@2001,1003,1001,1003) will be interpreted as (@1001,1003,2001).

• When sequential scanning is disabled (OFF), the channels remain in the

order presented in the scan list (see exception below). Multiple occurrences of the same channel are allowed. For example, (@2001,2001,2001) and (@3010,1003,1001,1005) are valid and the channels will be scanned in the order presented.

• When you specify a range of channels in the scan list, the channels are

always sorted in ascending order, regardless of the scan order setting. Therefore, (@1009:1001) will always be interpreted as 1001, 1002, 1003, etc.

• If you define a scan list with the sequential mode enabled and later

disable the mode, the scan list will not be reordered; however, the scan list will be treated as a non- sequential list thereafter.

• If you have defined a scan list with the sequential mode disabled (OFF)

and later enable the mode, the channels will be reordered.

• Non- sequential scan lists are not stored as part of the instrument state

by the

*SAV command; in this case, the ordered mode will be enabled

and the scan list will be empty when the instrument state is restored (*RCL command).

34980A User’s Guide 57

2 Features and Functions

• The scan order setting is stored in volatile memory and the ordered

Remote Interface Operation: ROUTe:SCAN:ORDered {OFF|ON}

Viewing Readings Stored in Memory

• During a scan, the instrument automatically adds a time stamp to all

• You can store at least 500,000 readings in memory and all readings are

• Each time you start a new scan, the instrument clears all readings

mode will be enabled when power is turned off or after a Factory Reset (

*RST command).

readings and stores them in memory. You can read the contents of memory at any time, even during a scan. Reading memory is not cleared when you read it.

automatically time stamped. If memory overflows, a status register bit is set and new readings will overwrite the first (oldest) readings stored. The most recent readings are always preserved.

(including alarm data) stored in reading memory from the previous scan. Therefore, the contents of memory are always from the most recent scan.

• The instrument clears all readings from memory after a Factory Reset

*RST command), after an Instrument Preset (SYSTem:PRESet

( command), or when mainframe power is cycled.

• The instrument clears all readings from memory when a new scan is

initiated, when any measurement parameters are changed ( and

SENSe commands), and when the triggering configuration is

CONFigure

changed (TRIGger commands).

• While a scan is running, the instrument automatically stores the

minimum and maximum readings and calculates the average for each channel. You can read these values at any time, even during a scan.

• Each reading is stored with measurement units, time stamp, channel

number, and alarm status information. From the remote interface, you can specify which information you want returned with the readings (from the front panel, all of the information is available for viewing). See “Reading Format” on page 56 for more information.

• Readings acquired during a Monitor are not stored in memory

(however, all readings from a scan in progress at the same time are stored in memory).

• The

INITiate command stores readings in memory. Use the FETCh?

command to retrieve stored readings from memory (the readings are not erased when you read them).

58 34980A User’s Guide

Features and Functions 2

Front Panel Operation: View > READINGS

Remote Interface Operation: The following command retrieves stored

readings from memory (the readings are not erased).

FETCh?

Use the following commands to query the statistics on the readings stored in memory for a specific channel or from the internal DMM. These commands do not remove the data from memory.

CALC:AVER:MIN? (@3005) CALC:AVER:MIN:TIME? (@3005)

CALC:AVER:MAX? (@3005) CALC:AVER:MAX:TIME? (@3005)

CALC:AVER:AVER? (@3005)

CALC:AVER:COUNT? (@3005)

CALC:AVER:PTPEAK? (@3005)

Minimum reading on channel Time minimum was logged

Maximum reading on channel Time maximum was logged

Average of all readings on channel

Number of readings taken on channel

Peak- to- peak (maximum–minimum)

The following command retrieves the last reading taken on channel 1 on the module in slot 3 during a scan.

DATA:LAST? (@3001)

The following command clears the contents of statistics memory for the selected channel.

CALC:AVER:CLEAR (@3001)

Use the following command to determine the total number of readings stored in memory (all channels) from the most recent scan.

DATA:POINTS?

The following command reads and clears the specified number of readings from memory. This allows you to continue a scan without losing data stored in memory (if memory becomes full, new readings will overwrite the first readings stored). The specified number of readings are cleared from memory, starting with the oldest reading.

DATA:REMOVE? 12

34980A User’s Guide 59

2 Features and Functions

Monitor Mode

In the Monitor mode, the instrument takes readings as often as it can on a single channel or the internal DMM, even during a scan. This feature is useful for troubleshooting your system before a test or for watching an important signal.

• Any channel that can be “read” by the instrument can be monitored.

• Readings acquired during a Monitor are not stored in memory but they

• The Monitor mode is equivalent to making continuous measurements

This includes any combination of temperature, voltage, resistance, current, frequency, or period measurements on multiplexer channels. You can also monitor a digital input channel or the totalizer count on the digital modules. You can also monitor measurements on the internal DMM, independent of any channel measurements.

are displayed on the front panel; however, all readings from a scan in progress at the same time are stored in memory.

on a single channel or the internal DMM with an infinite scan count. Only one channel can be monitored at a time but you can change the channel being monitored at any time.

• A scan in progress always has priority over the Monitor function.

• Channels do not have to be part of an active scan list to be monitored;

however, the channel must be configured for a measurement in order to be monitored.

• The Monitor mode ignores all trigger settings and takes continuous

readings on the selected channel using the IMMediate (continuous) source.

• The Monitor mode is automatically enabled on all channels that are

part of the active scan list. If you define the scan list after monitoring has already been enabled, any channels that are not part of the active scan list will be ignored during the monitor operation (no error is generated).

• Mx+B scaling and alarm limits are applied to the selected channel

during a Monitor and all alarm data is stored in the alarm queue (which will be cleared if power fails).

• You can monitor a digital input channel or totalizer channel even if the

channel is not part of the scan list (the internal DMM is not required either). The count on a totalizer channel is not reset when it is being monitored (the Monitor ignores the totalizer reset mode).

• If a channel that is currently being monitored is manually closed or

opened, the Monitor operation will be disabled on that channel.

60 34980A User’s Guide

Features and Functions 2

Front Panel Operation: DMM or Channel (Measure)

For channel monitoring, turn the knob to the desired channel. To stop a Monitor, press the lighted key again.

Remote Interface Operation: Use the following command to select between

the channel Monitor mode (default) and the internal DMM monitor mode.

ROUTe:MONitor:MODE {CHANnel|DMM}

The following program segment selects the channel to be monitored (specify only one channel) and enables the Monitor function.

ROUTE:MON:CHAN (@1003) ROUTE:MON:CHAN:ENABLE ON,(@1003) ROUTE:MON:STATE ON

The following program segment enables the Monitor function on the internal DMM:

ROUTE:MON:MODE DMM ROUTE:MON:STATE ON

To read the monitor data from the selected channel or the internal DMM, send the following command. Each reading is returned with measurement units, time stamp, channel number, and alarm status information (see “Reading Format” on page 56).

ROUTe:MONitor:DATA?

34980A User’s Guide 61

2 Features and Functions

System-Related Operations

This section gives information on system- related topics such as instrument state storage, error conditions, self- test, and front- panel display control. This information is not directly related to making measurements but is an important part of operating the instrument.

Firmware Revision

The mainframe, the internal DMM, and each of the plug- in modules has its own microprocessor. You can query each to determine which version of firmware is installed. For the mainframe, three firmware revision numbers are returned: mainframe revision, boot code revision, and front- panel revision. For the internal DMM and all plug- in modules, one firmware revision number is returned.

Front Panel Operation: Utility > FIRMWARE > REVISIONS

Use the knob to scroll through the revision numbers for the mainframe, internal DMM, and each installed module.

Remote Interface Operation: Use the following command to read the

mainframe firmware revision numbers (be sure to dimension a string variable with at least 72 characters).

*IDN?

The above command returns a string in the form:

AGILENT TECHNOLOGIES,34980A,<Serial Number>,m.mm–b.bb–f.ff–d.dd

m.mm

b.bb

d.dd

Use the following command to read the firmware revision number of the module in the specified slot (be sure to dimension a string variable with at least 73 characters).

= Mainframe revision number = Boot code revision number

f.ff

= Front-panel revision number = Internal DMM revision number

SYSTem:CTYPe? <slot>

This command returns a string in the form:

AGILENT TECHNOLOGIES,<Model Number>,<Serial Number>,<Firmware Rev>

“0” is always returned for the Serial Number field. The Firmware Revision has the form R.RR and indicates the revision of firmware currently in use on the specified module.

62 34980A User’s Guide

Product Firmware Updates

As new product features and enhancements become available, you can easily update your mainframe firmware to ensure optimum compatibility. The latest firmware updates are available from the Agilent 34980A product page at www.agilent.com/find/34980a (go to “Software & Firmware Downloads”).

Instrument State Storage

The instrument has five storage locations in non- volatile memory to store instrument states, numbered 1 through 5. You can assign a user- defined name to each of locations 1 through 5.

• You can store the instrument state in any of the five locations, but you

can only recall a state from a location that contains a previously stored state.

• The instrument stores the state of all plug- in modules including all

channel configurations, scanning setups, and Mx+B scaling values. However, note that only the measurement attributes of the currently- selected function (range, resolution, etc.) will be preserved in the stored states.

Features and Functions 2

• Before recalling a stored state, the instrument verifies that the same

plug- in module types are installed in each slot. If a different module type is installed, the instrument will perform the equivalent of a Factory Reset (

• When shipped from the factory, storage locations 1 through 5 are

empty. You can change the factory configuration such that a Factory Reset (

• You can name a location from the front panel or over the remote

interface but you can recall a named state only from the front panel. The name can contain up to 12 characters. The first character must be a letter (A- Z), but the remaining 11 characters can be letters, numbers (0- 9), or the underscore character (“_”). Blank spaces are not allowed. An error is generated if you specify a name with more than 12 characters.

• A Factory Reset (

stored in memory. Once a state is stored, it remains until it is overwritten or specifically deleted.

*RST command) is issued when power is restored.

*RST command).

*RST command) does not affect the configurations

34980A User’s Guide 63

2 Features and Functions

Front Panel Operation: Store/Recall > STORE|RECALL|DELETE|RENAME|AUTO

To rename a location, select RENAME. Press the arrow keys to move the cursor to a specific position and then turn the knob to select the desired letter or number. To clear the name of a location, change each character to “ ^ ” (starting with the rightmost character) and then press the left arrow key to move to the next character.

To automatically recall a specific location when power is restored, select AUTO. Use the knob to scroll through the available locations containing a stored state.

Remote Interface Operation: Use the following commands to store and

recall instrument states.

*SAV {1|2|3|4|5} *RCL {1|2|3|4|5}

To assign a user- defined name to a stored state to be recalled from the front panel, see the following example. From the remote interface, you can only recall a stored state using a number (1 through 5).

MEM:STAT:NAME 1,TEST_RACK_1

To configure the instrument to automatically recall location 2 when power is restored, send the following commands.

*SAV 2 MEM:STATE:RECALL:SELECT 2 MEM:STATE:RECALL:AUTO ON

Error Conditions

When the front panel ERROR annunciator turns on, one or more command syntax or hardware errors have been detected. A record of up to 20 errors can be stored in the instrument’s error queue. Each remote interface I/O session (i.e., GPIB, USB, LAN, etc.) has its own interface- specific error queue. Errors appear in the error queue of the I/O session that caused the error (the front panel reports errors from all I/O sessions).

For a complete listing of the error messages, see the Agilent 34980A

Programmer’s Reference Help file, located on the Product Reference CD- ROM. The CD- ROM is located inside the rear cover of this manual.

• The instrument beeps once each time a command syntax or hardware

error is generated.

• A special global error queue holds all power- on and hardware- related

errors (e.g., over- temperature, Safety Interlock, etc.).

64 34980A User’s Guide

Features and Functions 2

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

returned is the first error that was stored. Errors are cleared as you read them. Once you have read all of the interface-specific errors, the errors in the global queue are retrieved.

• Errors are cleared as you read them. When you have read all errors

from the interface- specific and global error queues, the ERROR annunciator turns off and the errors are cleared.

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

(the most recent error) is replaced with -350,“Error queue overflow”. No additional errors are stored until you remove errors from the queue. If no errors have occurred when you read the error queue, the instrument responds with +0,“No error”.

• The front panel reports errors from all I/O sessions as well as the

global error queue.

• The interface- specific and global error queues are cleared by the

*CLS

(Clear Status) command and when power is cycled. The errors are also cleared when you read the error queue. The error queue is not cleared by a Factory Reset (

*RST command) or an Instrument Preset

(SYSTem:PRESet command).

Front Panel Operation: View > ERROR QUEUE

Use the knob to scroll through the errors. Press the right arrow key to view the text of the error message. All errors are cleared when you exit the menu.

Remote Interface Operation: The following command reads and clears one

error from the queue.

SYSTem:ERRor?

34980A User’s Guide 65

2 Features and Functions

Self-Test

A power- on self- test occurs automatically when you turn on the instrument. This limited test assures you that the instrument and all installed plug- in modules are operational. This self-test does not perform the extensive self test described below.

A complete self- test actually performs a series of internal tests and takes approximately 20 seconds to execute. If all tests pass, you can have high confidence that the instrument and all installed plug- in modules are operational. This feature is available from the remote interface only.

• If you have a 34951A Isolated DAC Module installed, the complete

• The complete self- test will abort if any signals are connected to ABus1

self- test will require an additional 15 seconds to complete per DAC module (a memory test is performed).

via the rear- panel Analog Bus connector (pins 4, 5, and 9; see “Analog

Buses” on page 15). Be sure to disconnect any signals from ABus1 prior

to running the self-test.

• If the power-on or complete self-test fails, and error is stored in the

error queue. See the Agilent 34980A Service Guide for more information on returning the instrument to Agilent for service.

• Following the complete self- test, the instrument issues a Factory Reset

*RST command).

(

Remote Interface Operation: The following command returns “+0” if the

self- test is successful or “+1” if it fails.

*TST?

Front-Panel Display Control

For security reasons or for a slight increase in measurement rates, you may want to turn off the front- panel display. From the remote interface, you can also display up to 18 characters on the upper line of the front- panel display.

• You can disable the front- panel display only by sending a command

from the remote interface (i.e., you cannot disable the front panel while in local operation).

• When disabled, the entire front- panel display goes dark and all display

annunciators except ERROR, HOT, and Safety Interlock are disabled.

• The front-panel display is automatically enabled when power is cycled,

after a Factory Reset ( (SYSTem:PRESet command).

66 34980A User’s Guide

*RST command), or after an Instrument Preset

Features and Functions 2

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

from the remote interface. The instrument can display up to 18 characters on the upper line of the front- panel display; any additional characters are truncated (no error is generated). You can use letters (A- Z), numbers (0- 9), and special characters like “@”, “%”, “*”, etc. Use the “#” character to display a degree symbol ( ° ). Commas, periods, and semicolons share a display space with the preceding character, and are not considered individual characters.

• While a message is displayed on the front panel, readings from a scan

or monitor are not sent to the front- panel display.

• Sending a text message to the display overrides the display state;

this means that you can display a message even if the display is turned off. In addition, pressing any front- panel key will clear the text message.

Remote Interface Operation: The following command turns off the

front- panel display.

DISPLAY OFF

The following command displays a message on the front panel and turns on the display if currently disabled (the quotes are not displayed).

DISPLAY:TEXT "SCANNING ..."

To clear the message displayed on the front panel (without changing the display state), send the following command.

DISPLAY:TEXT:CLEAR

Front-Panel Number Format

The instrument can show numbers on the front- panel display with periods or commas for the decimal point (radix) and thousands separator.

This feature is available from the front panel only.

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

change when power has been off, after a Factory Reset ( command), or after an Instrument Preset (SYSTem:PRESet command).

• When shipped from the factory, a period is used as the radix character

and commas are used for the digits separator (e.g., +1.234,56 VDC).

Front Panel Operation: Utility > MISC. SETTINGS > RADIX|THOUSAND SEPARATOR

*RST

34980A User’s Guide 67

2 Features and Functions

Real-Time System Clock

During a scan, the instrument stores all readings and alarms with the current time and date (based on a 24- hour clock).

• When shipped from the factory, the instrument is set to the current

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

Front Panel Operation: Utility > DATE/TIME

Remote Interface Operation: The following commands show how to set the

time and date.

time and date for Greenwich Mean Time (GMT).

when power has been off, after a Factory Reset ( or after an Instrument Preset (SYSTem:PRESet command).

*RST command),

SYST:TIME 15,30,23.000 SYST:DATE 2004,11,24

Relay Cycle Count

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

• In addition to the channel relays, you can also query the count on the

Analog Bus relays and bank relays.

• You can query the st ate of six relays associated with function selection

and isolation on the internal DMM. These relays are numbered K102 through K107.

• You can reset the cycle count on any of the channel relays, Analog Bus

relays, or bank relays (allowed only from remote) but the instrument must be unsecured. See “To Unsecure the Instrument for

Calibration” on page 70 for more information.

Front Panel Operation: View > RELAY CYCLES

Set time to 3:30:23.000 PM Set date to November 21, 2004

Turn the knob to read the count on the desired channel relay or Analog Bus relay.

68 34980A User’s Guide

Remote Interface Operation: To read the count on either the specified

internal DMM relay or module channel relays, send the following commands.

DIAG:DMM:CYCLES? 2 DIAG:RELAY:CYCLES? (@1003,1013)

To reset the cycle count on the specified module channel relays, send the following command (the instrument must be unsecured).

DIAG:RELAY:CYCLES:CLEAR (@1003,1911)

SCPI Language Version

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

• You can query the SCPI version from the remote interface only.

• The SCPI version is returned in the form “YYYY.V”, where “YYYY”

represents the year of the version, and “V” represents a version number for that year (for example, 1994.0).

Features and Functions 2

Remote Interface Operation: SYSTem:VERSion?

34980A User’s Guide 69

2 Features and Functions

Calibration Overview

This section gives a brief introduction to the calibration features of the instrument and plug- in modules. For a more detailed discussion of the calibration procedures, see the Agilent 34980A Service Guide.

Calibration Security

This feature allows you to enter a security code to prevent accidental or unauthorized calibrations of the instrument. The specified code is used to unsecure the mainframe and all installed modules. When you first receive your instrument, it is secured. Before you can calibrate the instrument, you must unsecure it by entering the correct security code.

• The security code is set to “AT34980” when the instrument is shipped

from the factory. The security code is stored in non-volatile memory in the mainframe, and does not change when power has been off, after a Factory Reset ( (SYSTem:PRESet command).

*RST command), or after an Instrument Preset

• The security code can contain up to 12 characters. The first character

must be a letter (A- Z), but the remaining 11 characters can be letters, numbers (0- 9), or the underscore character (“_”). Blank spaces are not allowed. You do not have to use all 12 characters but the first character must always be a letter.

To Unsecure the Instrument for Calibration

You can unsecure the instrument from either the front panel or over the remote interface. The instrument is secured when shipped from the factory.

Once you enter a security code, that code must be used for both front- panel and remote operation. For example, if you secure the instrument from the front panel, you must use that same code to unsecure it from the remote interface.

Front Panel Operation: Utility > CALIBRATE > UNSECURE

Remote Interface Operation: To unsecure the instrument, send the following

command (the factory security code is shown).

CAL:SECURE:STATE OFF,AT34980

70 34980A User’s Guide

Features and Functions 2

To Secure the Instrument for Calibration

You can secure the instrument either from the front panel or over the remote interface. The instrument is secured when shipped from the factory.

Front Panel Operation: Utility > CALIBRATE > SECURE

Remote Interface Operation: To secure the instrument, send the following

command (the factory security code is shown).

CAL:SECURE:STATE ON,AT34980

To Change the Security Code

To change the security code, you must first unsecure the instrument, and then enter a new code. Make sure you have read the security code rules described on page 70 before attempting to change the security code.

Front Panel Operation: Utility > CALIBRATE > SET CAL CODE

To change the security code, unsecure the instrument using the old security code. Then go back into the menu and change the code. Changing the code from the front panel also changes the security code as seen from the remote interface.

Remote Interface Operation: To change the security code, unsecure the

instrument using the old security code. Then enter the new code as shown below.

CAL:SECURE:STATE OFF,AT34980 CAL:SECURE:CODE SN123456789

Unsecure with old code Enter new code

34980A User’s Guide 71

2 Features and Functions

Calibration Count

You can query the instrument to determine how many calibrations have been performed on the entire mainframe, the digital modules, or the internal DMM. Note that your instrument was calibrated before it left the factory. When you receive your instrument, be sure to read the various counts to determine the initial values.

• The calibration count is stored in non- volatile memory in the

• The calibration counts increments up to a maximum of 4,294,967,295

• The calibration count is also incremented with calibrations of DAC

mainframe, and does not change when power has been off, after a Factory Reset ( (SYSTem:PRESet command).

after which they roll over to “0”. Since the value increments by one for each calibration point, a complete calibration may increase the value by many counts.

channels on the 34951A Isolated DAC Module and 34952A Multifunction Module.

*RST command), or after an Instrument Preset

Front Panel Operation: Utility > CALIBRATE > COUNT

Remote Interface Operation: CALibration:COUNt?

72 34980A User’s Guide

Calibration Message

The instrument allows you to store one message in calibration memory in the mainframe, a digital module, or the internal DMM. For example, you can store such information as the date when the last calibration was performed, the date when the next calibration is due, the instrument’s serial number, or even the name and phone number of the person to contact for a new calibration.

• You can record a calibration message only from the remote interface

and only when the instrument is unsecured. You can read the message (mainframe message only) from either the front- panel or over the remote interface. You can read the calibration message whether the instrument is secured or unsecured.

• The calibration message may contain up to 40 characters. From the

front panel, you can view 18 characters of the message at a time.

• Storing a calibration message will overwrite any message previously

stored in memory.

Features and Functions 2

• The calibration message is stored in non- volatile memory in the

mainframe, a digital module, or the internal DMM, and does not change when power has been off, after a Factory Reset ( or after an Instrument Preset (SYSTem:PRESet command).

*RST command),

Front Panel Operation: Utility > CALIBRATE > CAL MESSAGE

Remote Interface Operation: The following example shows how to store a

message in calibration memory on the module in slot 3.

CAL:STRING "CAL: 21 NOV 2005",3

34980A User’s Guide 73

2 Features and Functions

Remote Interface Configuration

This section gives information on configuring the instrument for remote interface communication. For more information on the SCPI commands available to program the instrument over the remote interface, see the

Programmer’s Reference Help file included on the Agilent 34980A Product Reference CD- ROM. The CD- ROM is located inside the rear cover

of this manual.

The Agilent 34980A supports GPIB, USB, and LAN interfaces. All three interfaces are enabled at power on. The corresponding front- panel annunciator turns on whenever there is activity on the remote interface.

GPIB Interface You need only set the GPIB address for the instrument

and connect it to your PC using a GPIB cable (sold separately).

USB Interface There is nothing to configure on your instrument for a

USB connection. Just connect the instrument to your PC using a USB 2.0 cable (sold separately).

LAN Interface By default, DHCP is enabled on the instrument, which may

enable network communication over the LAN interface (10BaseT/100BaseTx). You may need to set several configuration parameters as described in the LAN configuration sections that follow. A crossover LAN cable is shipped with your instrument.

NOTE

To easily configure and verify an interface connection between the 34980A and your PC, you can use the Agilent IO Libraries Suite (E2094M Agilent IO Libraries for Windows) or an equivalent. For more information about Agilent's I/O connectivity software, go to www.agilent.com/find/iolib.

• Agilent IO Libraries Suite for Windows information and to install this software, see the Automation-Ready CD, which is shipped with your 34980A.

• Previous versions of the Agilent IO Libraries for Windows 2000/ME/XP. For more information and to download this software from the Web, go to www.agilent.com/find/iolib.

For more information on connecting instruments to USB, LAN, and GPIB and how to configure and troubleshoot these interfaces, refer to the Agilent Connectivity Guide.

98/2000/ME/XP. For more

98/NT/

If you have installed the Agilent IO Libraries Suite, you can access the guide from the Agilent IO Libraries Control icon. Or, you can download the guide from the Web at www.agilent.com/find/connectivity.

74 34980A User’s Guide

GPIB Interface

Each device on the GPIB (IEEE-488) interface must have a unique address. You can set the instrument’s address to any value between 0 and 30. The address is set to “9” when the instrument is shipped from the factory.

• Your computer’s GPIB interface card has its own address. Be sure to

avoid using the computer’s address for any instrument on the interface bus.

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

change when power has been off, after a Factory Reset ( command), or after an Instrument Preset (SYSTem:PRESet command).

Front Panel Operation: Utility > REMOTE I/O > GPIB > GPIB ADDRESS

To set the GPIB address, turn the knob (or use the number keypad) to select the desired address.

Remote Interface Operation: SYSTem:COMMunicate:GPIB:ADDRess

Features and Functions 2

*RST

USB Interface

For the USB interface, no configuration parameters are required to set up the instrument. Connect your instrument to a USB port on your computer. Note that it may take several seconds for the computer to recognize and establish a connection to the instrument.

LAN Interface

By default, DHCP is enabled on the instrument, which may enable network communication over the LAN interface. You may need to set several configuration parameters as described in this section.

34980A User’s Guide 75

2 Features and Functions

34980A Web Browser Interface

The Agilent 34980A provides a Web Interface which is built into the instrument. You can use this interface over LAN for remote access and control of the instrument via a Java Microsoft® Internet Explorer.

To access and use the 34980A Web Interface:

1 Establish a LAN interface connection from your computer to

2 Open your computer’s Web browser.

3 Launch the 34980A Web Interface by entering the IP address of your

4 Follow the instructions in the 34980A Web Interface’s on- line Help.

- enabled Web browser, such as

the 34980A.

34980A, or its fully-qualified host name, in the browser address field.

Agilent 34980A Web Interface

If desired, you can control access to the 34980A Web Interface using password protection. As shipped from the factory, no password is set. To set a password (available from the front panel only), navigate to the

WEB PASSWORD menu selection from the 34980A front panel.

Utility > REMOTE I/O > LAN > LAN SETTINGS > MODIFY > . . . WEB PASSWORD

76 34980A User’s Guide

Features and Functions 2

DHCP

DHCP (Dynamic Host Configuration Protocol) is a protocol for automatically assigning a dynamic IP address to a device on a network. DHCP is typically the easiest way to configure your instrument for remote communication using the LAN interface.

If you change the DHCP setting, you must cycle power on the 34980A to activate the new setting.

• When DHCP is enabled (factory setting), the instrument will try to

obtain an IP address from a DHCP server. If a DHCP server is found, it will assign a dynamic IP address, Subnet Mask, and Default Gateway to the instrument.

• When DHCP is disabled or unavailable, the instrument will use the

static IP address, Subnet Mask, and Default Gateway during power- on.

• If a DHCP LAN address is not assigned by a DHCP server, then a static

IP will be assumed after approximately 2 minutes.

• The DHCP setting is stored in non- volatile memory, and does not

change when power has been off, after a Factory Reset (

*RST

command), or after an Instrument Preset (SYSTem:PRESet command).

Front Panel Operation:

Utility > REMOTE I/O > LAN > LAN SETTINGS > MODIFY > DHCP

Remote Interface Operation:

SYSTem:COMMunicate:LAN:DHCP {OFF|ON}

IP Address

An Internet Protocol (IP) Address is required for all IP and TCP/IP communications with the instrument. If DHCP is enabled (factory setting), the specified static IP address is not used. However, if the DHCP server fails to assign a valid IP address, the currently configured static IP address will be used.

If you change the IP address, you must cycle power on the 34980A to activate the new setting.

• The default IP Address for the 34980A is “169.254.9.80”.

34980A User’s Guide 77

2 Features and Functions

• Dot- notation addresses (“nnn.nnn.nnn.nnn” where “nnn” is a byte

• If you are planning to use a static IP address on a Corporate LAN,

value) must be expressed with care, as most web software on the computer will interpret byte values with leading zeros as octal numbers. For example, “255.255.020.011” is actually equivalent to decimal “255.255.16.9” not “255.255.20.11” because “.020” is interpreted as “16” expressed in octal, and “.011” as “9”. To avoid confusion, use only decimal expressions of byte values (0 to 255), with no leading zeros.

For example, the 34980A assumes that all dot-notation addresses are expressed as decimal byte values and strips all leading zeros from these byte values. Thus, attempting to set an IP address of “255.255.020.011” will become “255.255.20.11” (a purely decimal expression). Be sure to enter the exact expression, “255.255.20.11”, in your computer web software to address the instrument. Do not use “255.255.020.011” — the computer will interpret this address differently due to the leading zeros.

contact your network administrator to obtain a fixed IP address to be used exclusively for your instrument.

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

when power has been off, after a Factory Reset ( after an Instrument Preset (

SYSTem:PRESet command).

*RST command), or

Front Panel Operation:

Utility > REMOTE I/O > LAN > LAN SETTINGS > MODIFY > DHCP OFF > AUTO IP OFF > IP ADDRESS

Remote Interface Operation:

SYSTem:COMMunicate:LAN:IPADdress <address>

Auto-IP

The Auto- IP standard automatically assigns an IP address to the 34980A when on a network that does not have DHCP servers.

If you change the Auto- IP configuration, you must cycle power on the 34980A to activate the new setting.

• Auto- IP allocates IP addresses from the link-local address range

(169.254.xxx.xxx).

• From the factory, the Auto-IP setting is enabled.

• The Auto- IP setting is stored in non- volatile memory, and does not

change when power has been off, after a Factory Reset (

*RST

command), or after an Instrument Preset (SYSTem:PRESet command).

78 34980A User’s Guide

Features and Functions 2

Front Panel Operation:

Utility > REMOTE I/O > LAN > LAN SETTINGS > MODIFY > DHCP OFF > AUTO IP

Remote Interface Operation:

SYSTem:COMMunicate:LAN:AUTOip (OFF|ON}

Subnet Mask

The instrument uses the Subnet Mask to determine if a client IP address is on the same local subnet. When a client IP address is on a different subnet, all packets must be sent to the Default Gateway. Contact your network administrator to determine if subnetting is being used and for the correct Subnet Mask.

If you change the Subnet Mask, you must cycle power on the 34980A to activate the setting.

• The default Subnet Mask for the 34980A is “255.255.0.0”.

• If DHCP is enabled, the specified Subnet Mask is not used. However,

if the DHCP server fails to assign a valid IP address, the currently configured Subnet Mask will be used.

• Dot- notation addresses (“nnn.nnn.nnn.nnn” where “nnn” is a byte

For example, the 34980A assumes that all dot-notation addresses are expressed as decimal byte values and strips all leading zeros from these byte values. Thus, attempting to set a Subnet Mask of “255.255.020.011” will become “255.255.20.11” (a purely decimal expression). Be sure to enter the exact expression, “255.255.20.11”, in your computer web software to address the instrument. Do not use “255.255.020.011” — the the computer will interpret this address differently due to the leading zeros.

• A value of “0.0.0.0” or “255.255.255.255” indicates that subnetting is not

being used.

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

when power has been off, after a Factory Reset (

*RST command), or

after an Instrument Preset (SYSTem:PRESet command).

34980A User’s Guide 79

2 Features and Functions

Front Panel Operation:

Utility > REMOTE I/O > LAN > LAN SETTINGS > MODIFY > DHCP OFF > AUTO IP OFF > . . . SUBNET MASK

Remote Interface Operation:

SYSTem:COMMunicate:LAN:SMASk <mask>

Default Gateway

A Default Gateway address allows the instrument to communicate with systems that are not on the local subnet. Thus, this is the Default Gateway where packets are sent which are destined for a device not on the local subnet, as determined by the Subnet Mask setting. Contact your network administrator to determine if a gateway is being used and for the correct address.

If you change the Default Gateway, you must cycle power on the 34980A to activate the new setting.

• The default for the 34980A is “0.0.0.0” (no gateway, and subnetting is

not being used).

• If DHCP is enabled, the specified Default Gateway is not used.

However, if the DHCP server fails to assign a valid IP address, the currently configured Default Gateway will be used.

• Dot- notation addresses (“nnn.nnn.nnn.nnn” where “nnn” is a byte

For example, the 34980A assumes that all dot-notation addresses are expressed as decimal byte values and strips all leading zeros from these byte values. Thus, attempting to set a Default Gateway of “255.255.020.011” will become “255.255.20.11” (a purely decimal expression). Be sure to enter the exact expression, “255.255.20.11”, in your computer web software to address the instrument. Do not use “255.255.020.011” — the computer will interpret this address differently due to the leading zeros.

• The Default Gateway is stored in non- volatile memory, and does not

change when power has been off, after a Factory Reset ( command), or after an Instrument Preset (SYSTem:PRESet command).

*RST

80 34980A User’s Guide

Features and Functions 2

Front Panel Operation:

Utility > REMOTE I/O > LAN > LAN SETTINGS > MODIFY > DHCP OFF > AUTO IP OFF > . . . DEFAULT GATEWAY

Remote Interface Operation:

SYSTem:COMMunicate:LAN:GATEway <address>

Host Name

The Host Name is the host portion of the domain name, which is translated into an IP address.

If you change the Host Name, you must cycle power on the 34980A to activate the new setting.

• The default Host Name for the 34980A is “A- 34980A- nnn”, where nnn

is the instrument’s serial number representation.

• If Dynamic Domain Name System (DNS) is available on your network

and your instrument uses DHCP, the Host Name is registered with the Dynamic DNS service at power-on.

• If DHCP is enabled, the DHCP server can change the specified

Host Name.

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

when power has been off, after a Factory Reset (

*RST command), or

after an Instrument Preset (SYSTem:PRESet command).

Front Panel Operation:

Utility > REMOTE I/O > LAN > LAN SETTINGS > MODIFY > . . . HOST NAME

Remote Interface Operation:

SYSTem:COMMunicate:LAN:HOSTname "<name>"

34980A User’s Guide 81

2 Features and Functions

DNS Server

The Domain Name Service (DNS) is an Internet service that translates Domain names into IP addresses. Contact your network administrator to determine if DNS is being used and for the correct address.

If you change the DNS address, you must cycle power on the 34980A to activate the new setting.

• The default DNS Address for the 34980A is “0.0.0.0”.

• Dot- notation addresses (“nnn.nnn.nnn.nnn” where “nnn” is a byte

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

when power has been off, after a Factory Reset ( after an Instrument Preset (SYSTem:PRESet command).

*RST command), or

Front Panel Operation:

Utility > REMOTE I/O > LAN > LAN SETTINGS > MODIFY > DHCP OFF > AUTO IP OFF > . . . DNS SERVER

Remote Interface Operation:

SYSTem:COMMunicate:LAN:DNS <address>

82 34980A User’s Guide

Features and Functions 2

Domain Name

A domain name is a registered name on the Internet, which is translated into an IP address. This feature is available from the remote interface only.

If you change the Domain Name, you must cycle power on the 34980A to activate the new setting.

• If Dynamic Domain Name System (DNS) is available on your network

and your instrument uses DHCP, the Domain Name is registered with the Dynamic DNS service at power-on.

• If DHCP is enabled, the DHCP server can change the specified

Domain Name.

• The Domain Name is stored in non-volatile memory, and does not

change when power has been off, after a Factory Reset ( command), or after an Instrument Preset (SYSTem:PRESet command).

Remote Interface Operation:

*RST

SYSTem:COMMunicate:LAN:DOMain "<name>"

34980A User’s Guide 83

2 Features and Functions

Factory Reset State

The following tables show the state of the instrument after a *RST or

SYSTem:CPON command is executed.

Measurement Configuration Factory Reset State

Function Range Resolution Integration Time Input Resistance Channel Labels Channel Delay Reading Format Sample Count Trig ge r Co u n t Trigger Delay Trig ge r So u r c e

Scanning Operations Factory Reset State

Scan List Reading Memory Min, Max, and Average Sweep Count Trigger Interval Monitor in Progress

DC Volts Autorange 5½ Digits 1 PLC

Ω (fixed for all DCV ranges)

10 M No Change Automatic Delay Reading Only (no units, channel, time) 1 Sample per Trigger 1 Trigger Automatic Delay Immediate

Empty All Readings are Cleared All Statistical Data is Cleared 1 Sweep 0 Seconds (immediate) Stopped

Mx+B Scaling Factory Reset State

Scaling State Gain Factor (“M”) Offset Factor (“B”) Scale Label

84 34980A User’s Guide

Off 1 0 VDC

Module Hardware Factory Reset State

Features and Functions 2

Multiplexer Modules

All Channels Open 2-Wire/1-Wire Mode: No Change

Matrix Modules

All Channels Open 2-Wire/1-Wire Mode: No Change

GP Modules

RF Modules

Microwave Modules

All Channels Open

Channels b01 and b02 Selected (b=Bank)

34946A: Channels 101 and 201 to COM 34947A: Channels 101, 201, and 301 to COM

System Control Modules

34951A: DACs=0 Vdc, Trace Waveforms Cleared 34952A: DIO Ports=Input, Count=0, DACs=0 Vdc

System-Related Operations Factory Reset State

Display State Error Queue Stored States System Date System Time Temperature Units

On Errors Not Cleared No Change No Change No Change °C

34980A User’s Guide 85

2 Features and Functions

Instrument Preset State

The following tables show the state of the instrument after a

SYSTem:PRESet command is executed.

Measurement Configuration Preset State

Function Range Resolution Integration Time Input Resistance Channel Labels Channel Delay Reading Format Sample Count Trig ge r Co u n t Trigger Delay Trig ge r So u r c e

Scanning Operations Preset State

Scan List Reading Memory Min, Max, and Average Sweep Count Trigger Interval Monitor in Progress

No Change No Change No Change No Change No Change No Change No Change No Change No Change No Change No Change No Change

No Change All Readings are Cleared All Statistical Data is Cleared No Change No Change Stopped

Mx+B Scaling Preset State

Scaling State Gain Factor (“M”) Offset Factor (“B”) Scale Label

86 34980A User’s Guide

No Change No Change No Change No Change

Module Hardware Preset State

Features and Functions 2

Multiplexer Modules

All Channels Open 2-Wire/1-Wire Mode: No Change

Matrix Modules

All Channels Open 2-Wire/1-Wire Mode: No Change

GP Modules

RF Modules

Microwave Modules

All Channels Open

Channels b01 and b02 Selected (b=Bank)

34946A: Channels 101 and 201 to COM 34947A: Channels 101, 201, and 301 to COM

System Control Modules

34951A: DACs=0 Vdc, Trace Waveforms Cleared 34952A: DIO Ports=Input, Count=0, DACs=0 Vdc

System-Related Operations Preset State

Display State Error Queue Stored States System Date System Time Temperature Units

On Errors Not Cleared No Change No Change No Change °C

34980A User’s Guide 87

2 Features and Functions

88 34980A User’s Guide

Agilent Technologies Switch-Measure User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

Contents

Front Panel at a Glance

Rear Panel at a Glance

Rear Panel Connector Pinouts

External Trigger Input Connector (Male D-Sub)

Analog Bus Connector (Female D-Sub)

Annunciator Display Indicators

Front Panel Menu Reference

Instrument Rack Mounting

SCPI Language Conventions

Rules for Using a Channel List

General Measurement Configuration

Overview of Measurement Modes

Analog Buses

Measurement Functions

Measurement Range

Measurement Resolution

Custom A/D Integration Time

Autozero

Trigger Delay

Automatic Trigger Delays

Safety Interlock

User-Defined Channel Labels

2-Wire Versus 1-Wire Mode

Analog Bus and Internal DMM Considerations

Environmental Operating Conditions

Electrical Operating Conditions

Temperature Measurement Configuration

Measurement Units

Thermocouple Measurements

RTD Measurements

Thermistor Measurements

Voltage Measurement Configuration

DC Input Resistance

AC Low Frequency Filter

Resistance Measurement Configuration

Offset Compensation

Current Measurement Configuration

AC Low Frequency Filter

Frequency Measurement Configuration

Low Frequency Timeout

Mx+B Scaling

Scanning

Rules for Scanning

Adding Channels to the Scan List

Scan Trigger Source

Tri g ge r Co u nt

Sweep Count

Sample Count

Channel Delay

Automatic Channel Delays

Reading Format

Non-Sequential Scanning

Viewing Readings Stored in Memory

Monitor Mode

System-Related Operations

Firmware Revision

Product Firmware Updates

Instrument State Storage

Error Conditions

Self-Test

Front-Panel Display Control

Front-Panel Number Format

Real-Time System Clock

Relay Cycle Count

SCPI Language Version

Calibration Overview

Calibration Security

Calibration Count

Calibration Message

Remote Interface Configuration

GPIB Interface

USB Interface

LAN Interface

Factory Reset State

Instrument Preset State