Agilent Technologies 5951-2826, 5951-2827 User Manual

Operating Manual

Agilent Technologies

Single Input

Electronic Load Family

Agilent Part No. 5951-2826 Printed in USA: October, 1997
Microfiche Part No. 5951-2827 Updated: April, 2000

CERTIFICATION

Agilent Technologies. certifies that this product met its published specifications at time of shipment from the factory.
Agilent Technologies further certifies that its calibration measurements are traceable to the United States National Bureau
of Standards, to the extent allowed by the Bureau’s calibration facility, and to the calibration facilities of other
International Standards Organization members.

WARRANTY

This Agilent Technologies hardware product is warranted against defects in material and workmanship for a period of three
years from date of delivery. Agilent Technologies software and firmware products, which are designated by Agilent
Technologies for use with a hardware product and when properly installed on that hardware product, are warranted not to
fail to execute their programming instructions due to defects in material and workmanship for a period of 90 days from date
of delivery. During the warranty period Agilent Technologies will, at its option, either repair or replace products which
prove to be defective. Agilent Technologies does not warrant that the operation of the software, firmware, or hardware shall
be uninterrupted or error free.

For warranty service, with the exception of warranty options, this product must be returned to a service facility designated
by Agilent Technologies Customer shall prepay shipping charges by (and shall pay all duty and taxes) for products returned
to Agilent Technologies for warranty service. Except for products returned to Customer from another country, Agilent
Technologies shall pay for return of products to Customer.

Warranty services outside the country of initial purchase are included in Agilent Technologies product price, only if
Customer pays Agilent Technologies international prices (defined as destination local currency price, or U.S. or Geneva
Export price).

If Agilent Technologies is unable, within a reasonable time to repair or replace any product to condition as warranted, the
Customer shall be entitled to a refund of the purchase price upon return of the product to Agilent Technologies, Inc,.

LIMITATION OF WARRANTY

The foregoing warranty shall not apply to defects resulting from improper or inadequate maintenance by the Customer,
Customer-supplied software or interfacing, unauthorized modification or misuse, operation outside of the environmental
specifications for the product, or improper site preparation and maintenance. NO OTHER WARRANTY IS EXPRESSED
OR IMPLIED. AGILENT TECHNOLOGIES SPECIFICALLY DISCLAIMS THE IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.

EXCLUSIVE REMEDIES

THE REMEDIES PROVIDED HEREIN ARE THE CUSTOMER’S SOLE AND EXCLUSIVE REMEDIES. AGILENT
TECHNOLOGIES SHALL NOT BE LIABLE FOR ANY DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR
CONSEQUENTIAL DAMAGES, WHETHER BASED ON CONTRACT, TORT, OR ANY OTHER LEGAL THEORY.

ASSISTANCE

The above statements apply only to the standard product warranty. Warranty options, extended support contracts, product
maintenance agreements and customer assistance agreements are also available. Contact your nearest Agilent
Technologies Sales and Service office for further information on Agilent Technologies’ full line of Support Programs.

2

SAFETY SUMMARY

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

BEFORE APPLYING POWER.

Verify that the product is set to match the available line voltage and the correct fuse is installed.

GROUND THE INSTRUMENT.

This product is a Safety Class 1 instrument (provided with a protective earth terminal). To minimize shock hazard, the instrument chassis
and cabinet must be connected to an electrical ground. The instrument must be connected to the ac power supply mains through a three­conductor power cable, with the third wire firmly connected to an electrical ground (safety ground) at the power outlet. For instruments
designed to be hard-wired to the ac power lines (supply mains), connect the protective earth terminal to a protective conductor before any
other connection is made. 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. If the instrument is to be energized via an external autotransformer for
voltage reduction, be certain that the autotransformer common terminal is connected to the neutral (earthed pole) of the ac power lines
(supply mains).

FUSES.

Only fuses with the required rated current, voltage, and specified type (normal blow, time delay, etc.) should be used. Do not use repaired
fuses or short circuited fuseholders. To do so could cause a shock or fire hazard.

DO NOT OPERATE IN AN EXPLOSIVE ATMOSPHERE.

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

KEEP AWAY FROM LIVE CIRCUITS.

Operating personnel must not remove instrument covers. Component replacement and internal adjustments must be made by qualified
service personnel. Do not replace components with power cable connected. Under certain conditions, dangerous voltages may exist even
with the power cable removed. To avoid injuries, always disconnect power, discharge circuits and remove external voltage sources before
touching components.

DO NOT SERVICE OR ADJUST ALONE.

Do not attempt internal service or adjustment unless another person, capable of rendering first aid and resuscitation, is present.

DO NOT EXCEED INPUT RATINGS.

This instrument may be equipped with a line filter to reduce electromagnetic interference and must be connected to a properly grounded
receptacle to minimize electric shock hazard. Operation at line voltages or frequencies in excess of those stated on the data plate may
cause leakage currents in excess of 5.0 mA peak.

SAFETY SYMBOLS.

DO NOT SUBSTITUTE PARTS OR MODIFY INSTRUMENT.

Because of the danger of introducing additional hazards, do not install substitute parts or perform any unauthorized modification to the
instrument. Return the instrument to an Agilent Technologies Sales and Service Office for service and repair to ensure that safety features
are maintained.

Instruction manual symbol: the product will be marked with this symbol when it is necessary for the user to refer to the
instruction manual (refer to Table of Contents) .

Indicates hazardous voltages.
Indicate earth (ground) terminal.

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

The CAUTION sign denotes a hazard. It calls attention to an operating procedure, or the like, which, if not correctly
performed or adhered to, could result in damage to or destruction of part or all of the product. Do not proceed
beyond a CAUTION sign until the indicated conditions are fully understood and met.

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

3

SAFETY SUMMARY (continued)

GENERAL

Any LEDs used in this product are Class 1 LEDs as per IEC 825-l.

This ISM device complies with Canadian ICES-001. Cet appareil ISM est conforme à la norme NMB-001 du Canada.

ENVIRONMENTAL CONDITIONS

This instruments is intended for indoor use in an installation category II, pollution degree 2 environment. It is designed to
operate at a maximum relative humidity of 95% and at altitudes of up to 2000 meters. Refer to the specifications tables for
the ac mains voltage requirements and ambient operating temperature range.

SAFETY SYMBOL DEFINITIONS

Symbol Description Symbol Description

Direct current Terminal for Line conductor on permanently

installed equipment

Alternating current Caution, risk of electric shock

Both direct and alternating current Caution, hot surface

Three-phase alternating current Caution (refer to accompanying documents)

Earth (ground) terminal In position of a bi-stable push control

Protective earth (ground) terminal Out position of a bi-stable push control

Frame or chassis terminal On (supply)

Terminal for Neutral conductor on permanently
installed equipment
Terminal is at earth potential(Used for
measurement and control circuits designed to
be operated with one terminal at earth
potential.)

Herstellerbescheinigung

Diese Information steht im Zusammenhang mit den Anforderungen der Maschinenläminformationsverordnung vom 18
Januar 1991.

* Schalldruckpegel Lp <70 dB(A) * Am Arbeitsplatz * Normaler Betrieb * Nach EN 27779 (Typprufung).

Manufacturer’s Declaration

This statement is provided to comply with the requirements of the German Sound Emission Directive, from 18 January

1991.

Off (supply)

Standby (supply)
Units with this symbol are not completely
disconnected from ac mains when this switch is
off. To completely disconnect the unit from ac
mains, either disconnect the power cord or
have a qualified electrician install an external
switch.

* Sound Pressure Lp <70 dB(A) *At Operator Position * Normal Operation * According to EN 27779 (Type Test).

4

DECLARATION OF CONFORMITY

according to ISO/IEC Guide 22 and EN 45014

Manufacturer’s Name: Agilent Technologies, Inc.
Manufacturer’s Address: New Jersey Division

150 Green Pond Road
Rockaway, NJ 07866 U.S.A.

declares that the product

Product Name: Electronic Load
Model Number(s): Agilent 6060B, Agilent 6063B

conform(s) to the following Product Specifications:
Safety: HD 401S1/IEC348

EN 61010/IEC 1010-1 (1990) - Amendment 1 (1992)

EMC: CISPR 11:1990 / EN 55011:1991 Group 1, Class B

IEC 801-2:1991 / EN 50082-1:1992 4kV CD, 8 kV AD
IEC 801-3:1984 / EN 50082-1:1992 3 V/m
IEC 801-4:1988 / EN 50082-1:1992 0.5 kV Sig. Lines, 1 kV Power Lines

Supplementary Information:

The product herewith complies with the requirements of the Low Voltage Directive 73/23/EEC and the EMC
Directive 89/336/EEC.

--------------------------------------------------------

New Jersey, April, 1993 Mord Shamir / Quality Manager

European Contact: Your local Agilent Technologies Sales and Service Office or Agilent Technologies GmbH
Department TRE, Herrenberger Strasse 130, D-71034 Boeblingen (FAX:[phone])

Printing History

The current edition of this guide is indicated below. Reprints of this guide containing minor corrections and updates may
have the same printing date. New editions are identified by a new printing date and, in some cases, by a new part number.
A new edition incorporates all new or corrected material since the previous edition. Changes to the guide occurring
between editions are covered by change sheets shipped with the guide. Also, if the serial number prefix of your power
module is higher than those listed on the title page of this guide, then it may or may not include a change sheet. That is
because even though the higher serial prefix indicates a design change, that change may not affect the content of the guide.

Edition 1 May, 1991  Copyright 1993 Agilent Technologies, Inc.

Edition 2 ...... May 1993

..................... November, 1997

..................... Update April 2000

This document contains proprietary information protected by copyright. All rights are reserved. No part of this document
may be photocopied, reproduced, or translated into another language without the prior consent of Agilent Technologies The
information contained in this document is subject to change without notice.

5

Table of Contents

1. General Information

What’s in this Manual................................................................................................................................9

Reader Path................................................................................................................................................9

Options.......................................................................................................................................................9

Safety Requirements...................................................................................................................................10

Specifications.............................................................................................................................................10

2. Operation Overview

Introduction................................................................................................................................................19

Front Panel Description..............................................................................................................................19

Remote Programming.................................................................................................................................19

Local/Remote Control................................................................................................................................20

Programmable Features..............................................................................................................................20

Modes of Operation.................................................................................................................................20

Constant Current CC (Mode)..................................................................................................................20

Constant Resistance (CR) Mode..............................................................................................................22

Constant Voltage (CV) Mode..................................................................................................................23

Transient Operation.................................................................................................................................24

Triggered Operation................................................................................................................................27

Slew Rate and Minimum Transition Time...............................................................................................27

Input Current, Voltage, and Power Measurement...................................................................................28

Short On/Off............................................................................................................................................29

Input On/off.............................................................................................................................................30

Saving and Recalling Settings.................................................................................................................30

Reading Remote Programming Errors.....................................................................................................30

Status Reporting......................................................................................................................................30

Protection Features.....................................................................................................................................31

Resetting Latched Protection...................................................................................................................31

Overvoltage.............................................................................................................................................31

Overcurrent..............................................................................................................................................31

Overpower...............................................................................................................................................32

Overtemperature......................................................................................................................................32

Reverse Voltage......................................................................................................................................32

Control Connector......................................................................................................................................32

Remote Sensing.......................................................................................................................................32

Monitor Outputs......................................................................................................................................33

External Programming Input...................................................................................................................33

Fault.........................................................................................................................................................33

Port On/Off..............................................................................................................................................34

3. Installation

Introduction................................................................................................................................................35

Inspection...................................................................................................................................................35

Location and Cooling.................................................................................................................................36

Turn-On Checkout......................................................................................................................................36

Check Line Voltage.................................................................................................................................36

Connect the Power Cord..........................................................................................................................38

Turn-On/Selftest......................................................................................................................................38

Power Test...............................................................................................................................................37

6

Controller Connection................................................................................................................................39

GPIB Connector......................................................................................................................................39

GPIB Address..........................................................................................................................................40

Rear Panel Connectors and Switches.........................................................................................................40

Input Binding Posts.................................................................................................................................40

Control Connector...................................................................................................................................41

Trigger Connector...................................................................................................................................43

Sense Switch............................................................................................................................................43

Application Connections............................................................................................................................44

Wiring Considerations............................................................................................................................44

Local Sense Connections........................................................................................................................44

Remote Sense Connections....................................................................................................................44

Parallel Connections...............................................................................................................................45

Zero-Volt Loading Connections.............................................................................................................45

4. Local Operation

Introduction................................................................................................................................................49

Local Control Overview.............................................................................................................................52

Using The Function Keys...........................................................................................................................53

Turning the Input On/Off........................................................................................................................53

Setting the Mode of Operation................................................................................................................55

Setting CC Values...................................................................................................................................55

Setting CR Values...................................................................................................................................57

Setting CV Values...................................................................................................................................59

Transient Operation.................................................................................................................................60

Shorting the Input....................................................................................................................................61

Resetting Latched Protection...................................................................................................................61

Using The System Keys..............................................................................................................................61

Setting the GPIB Address........................................................................................................................62

Displaying Error Codes...........................................................................................................................62

Saving and Recalling Settings.................................................................................................................62

Changing "Wake-up" Settings.................................................................................................................63

Recalling the Factory Default Values......................................................................................................64

Table of Contents (continued)

5. Remote Operation

Introduction................................................................................................................................................65

Enter/Output Statements.............................................................................................................................65

GPIB Address.............................................................................................................................................65

Sending A Remote Command....................................................................................................................66

Getting Data Back From The Electronic Load...........................................................................................66

Remote Programming Commands..............................................................................................................66

CC Mode Example..................................................................................................................................70

CV Mode Example..................................................................................................................................70

CR Mode Example..................................................................................................................................70

Continuous Transient Operation Example...............................................................................................71

Pulsed Transient Operation Example......................................................................................................71

6. Calibration

Introduction................................................................................................................................................75

Example Programs.....................................................................................................................................75

Equipment Required...................................................................................................................................75

7

Table of Contents (continued)

Calibration Commands...............................................................................................................................76

Calibration Flowcharts...............................................................................................................................77

Example Program.......................................................................................................................................77

A. Considerations for Operating in Constant Resistance Mode.......................................................87

Index .......................................................................................................................................................................89

Agilent Sales and Support Offices...........................................................................................................93

8

1

General Information

What’s In This Manual

This chapter contains specifications that apply to the Single Input Electronic Load Family as well as information concerning
options and safety requirements. The remaining chapters in this manual contain instructions for installing, operating,
programming, and calibrating the Electronic Load as follows:

Chapter 2 "Operation Overview": describes all of the Electronic Load’s functions and briefly describes how they can be

controlled locally at the front panel and/or remotely via a GPIB controller.

Chapter 3 "Installation": includes turn-on checkout procedures as well as controller and application

connections.

Chapter 4 "Local Operation": describes in detail how to operate the Electronic Load at the front panel.

Chapter 5 "Remote Operation": provides an introduction to remote programming.

Chapter 6 "Calibration": contains calibration procedures for the Electronic Load and gives sample calibration

programs. Yearly calibration intervals are recommended.

Reader Path

If you are a first-time user, start with this manual, paying particular attention to Chapter 2. After installation (Chapter 3),
read Chapter 4 to learn front-panel operation. Programming users should then read Chapter 5 before going to the

Programming Reference Guide. Experienced programming users will probably refer only to the Programming Reference
Guide. The programming guide covers all of the programming details whereas Chapter 5 in this manual gives a few simple

examples to help you get started in writing computer programs.

Options

Unless one of the following line voltage options is ordered, the unit is shipped from the factory set for 120 Vac, 48-63 Hz ac
input power. If Option 100, 220, or 240 is ordered, the unit will be factory set for the appropriate line voltage. For
information about changing the line voltage setting, see "Turn-On Checkout" in Chapter 3.

100: Input Power, 100 Vac, 48-63 Hz

120: Input Power, 120 Vac, 48-63 Hz

220: Input Power, 220 Vac, 48-63 Hz
240: Input Power, 240 Vac, 48-63 Hz

Additional options are:

020:
908: One rack mount kit
909: One rack mount kit with handles
0L2:

0B3:

Front panel input binding posts

One extra Operating Manual and Programming Reference Guide

One Service Manual

General Information 9

Safety Requirements

This product is a Safety Class 1 instrument, which means that it is provided with a protective earth ground terminal. This
terminal must be connected to an ac source that has a 3-wire ground receptacle. Review the instrument rear panel and this
manual for safety markings and instructions before operating the instrument. Refer to the Safety Summary page at the
beginning of this manual for a summary of general safety information. Specific safety information is located at appropriate
places in this manual.

The Electronic Load is designed to comply with the following safety and environmental requirements:

•

IEC 348 - Safety requirements for electronic measuring apparatus.

•

CSA 22.2 No. 231 - Electronic instruments and scientific apparatus for special use and applications.

•

UL 1244 - Electrical and electronic measuring and testing equipment.

Specifications

Table 1-1 lists the specifications of the Single Input Electronic Loads. Specifications indicate warranted performance in the
25°C ± 5°C region of the total temperature range (0 to 55'C). Table 1-2 lists the supplemental characteristics of the Single

Input Electronic Loads. Supplemental characteristics indicate nonwarranted, typical performance and are intended to
provide additional information by describing performance that has been determined by design or type testing.

Table 1-1. Specifications

SPECIFICATIONS

AC INPUT RATING: Two internal switches permit operation from 100, 120, 220, or 240 Vac, nominal lines.

Amplitude: -13% to +6% nominal line voltage.

Frequency: 48 to 63 Hz

6060B 6063B

DC INPUT RATING
Current: 0 to 60 A 0 to 10 A
Voltage: 3 V to 60 V (see derated 3 V to 240 V (see derated
current detail) current detail)
Power: 300 W at 40°C (derated to 250 W at 40°C (derated to

225 W at 55°C) 187 W at 55°C)

OPERATING CHARACTERISTICS

10 General Information

DERATED CURRENT DETAIL

Table 1-1. Specifications (continued)

6060B 6063B

CONSTANT CURRENT MODE
Ranges

Low Range: 0 to 6 A 0 to 1 A
High Range: 0 to 60 A 0 to 10 A
Accuracy (after 30 sec wait): ± 0.1% ± 75 mA ± 0.15% ± 10 mA

both ranges both ranges

Regulation: 10 mA both ranges 8 mA both ranges

CONSTANT RESISTANCE MODE

Ranges

Low Range: 0.033 to 1
Middle Range: 1 to 1000
High Range: 10 to I 0,000

Accuracy

Low Range:
with
Middle and High Ranges: ± 0.3% ± 8 mS ± 0.3% ± 0.3 mS
with

CONSTANT VOLTAGE MODE

Range: 0 to 60 V 0 to 240 V
Accuracy: ± 0.1% ± 50 mv ± 0.12% ± 120 mV
Regulation: 10 mV (remote sense), 10 mV (remote sense)
40 mV (local sense) 40 mV (local sense)

TRANSIENT OPERATION

Modes: Continuous, pulsed, or toggled
Continuous Mode
Freq Range: 0.25 Hz to 10 kHz
Freq Accuracy: 3%
Duty Cycle Range: 3% to 97% (0.25 Hz to 1 kHz);
6% to 94% (1 kHz to 10 kHz)
Duty Cycle Accuracy: 6% of setting ± 2%

Pulsed Mode
Pulse Width: 50 µs ± 3% minimum; 4 s ± 3% maximum

Ω

Ω

Ω

±

0.8% ± 8 m

≥

6 V at input with ≥ 1 A at input

≥

6 V at input with ≥ 24 V at input

Ω

0.20 to 24
24 to 10,000
240 to 50,000

± 0.8% ± 200 m

Ω

Ω

Ω

Ω

General Information 11

Table 1-1. Specifications (continued)

TRANSIENT CURRENT LEVEL
Ranges

Low Range: 0 to 6 A 0 to 1 A
High Range: 0 to 60 A 0 to 10 A

Accuracy

Low Range: ± 0.1% ± 80 mA ± 0.18% ± 13 mA
High Range: ± 0.1% ± 350 mA ± 0.18% ± 50 mA

6060B 6063B
TRANSIENT RESISTANCE LEVEL
Ranges

Low Range: 0.033 to 1
Middle Range: 1 to 1000
High Range: 10 to 10,000

Accuracy

Low Range:
with
Middle Range: ± 0.3% ± 10 mS ± 0.3% ± 0.5 mS
with
High Range: ± 0.3% ± 10 mS ± 0.3% ± 0.4 mS
with

TRANSIENT VOLTAGE LEVEL
Range: 0 to 60 V 0 to 240 V
Accuracy: 0.1% ± 300 mV ± 0.15% ± 1.1 V

CURRENT READBACK
*Accuracy: 0.05% ± 65 mA ± 0.12% ± l0mA
*after 30 second wait.

VOLTAGE READBACK
Accuracy: 0.05% ± 45 mV ± 0.1%150 mV

POWER READBACK
Accuracy ±0.2% ± 4 W ±0.2% ± 3 W

PARD (20 Hz to 10 MHz noise)

Current: 4 mA rms/40 mA p-p 1 mA rms/10 mA p-p
Voltage: 6 mV rms 6 mV rms

±

0.8% ± 10 m

Ω

Ω

Ω

Ω

≥

6 A at input with ≥ 1 A at input

≥

6 V at input with ≥ 24 V at input

≥

6 V at input with ≥ 24 V at input

0.20 to 24
24 to 10,000
240 to 50,000

± 0.8% ± 200 m

Ω

Ω

Ω

Ω

12 General Information

Table 1-2. Supplemental Characteristics

6060B 6063B
CONSTANT CURRENT MODE
Resolution

Low Range: 1.6 mA 0.26 mA
High Range: 16 mA 2.6 mA
Temperature Coefficient 100 ppm/°C ±5 mA/°C 150 ppm/°C ±1 mA/°C
both ranges both ranges

CONSTANT RESISTANCE MODE
Resolution

Low Range: 0.27 m
Middle Range: 0.27 mS 0.011 mS
High Range: 0.027 mS 0.001 mS

Temperature Coefficient
Low Range: 800 ppm/°C ± 0.4 mΩ/°C 800 ppm/°C ± 10 mΩ/°C

Middle and High Ranges: 300 ppm/°C ± 0.6 m S/°C 300 ppm/°C ± 0.03 mS/°C

CONSTANT VOLTAGE MODE

Resolution: 16 mV 64 mV
Temperature Coefficient: 100 ppm/°C ± 5mV/°C 120 ppm/°C ± l0mV/°C

TRANSIENT OPERATION
Continuous Mode

Freq Resolution: 4% 4%
Duty Cycle Resolution: 4% 4%

TRANSIENT CURRENT LEVEL
Resolution

Low Range: 26 mA 4 mA
High Range: 260 mA 43 mA
Temperature Coefficient: 100 ppm/°C ± 7 mA/°C 180 ppm/°C ± 1.2 mA/°C

TRANSIENT RESISTANCE LEVEL
Resolution

Low Range: 4.3 m
Middle Range: 4.3 mS 0. 18 mS
High Range: 0.4 mS 0.018 mS

TRANSIENT VOLTAGE LEVEL

Resolution: 260 mV 1.0 V
Temperature Coefficient: 150 ppm/°C ± 5 mA/°C 120 ppm/°C ±10 mA/°C

CURRENT READBACK

Resolution: 17 mA (via GPIB) 27 mA (via GPIB)
20 mA (front panel) 10 mA (front panel)
Temperature Coefficient: 50 ppm/°C ± 5 mA/°C 100 ppm/°C ± 1 mA/°C

Ω

Ω

Ω

6 m

100 m

Ω

General Information 13

Table 1-2. Supplemental Characteristics (continued)

6060B 6063B

VOLTAGE READBACK

Resolution: 17 mV (via GPIB) 67 mV (via GPIB)
20 mV (front panel) 100 mV (front panel)
Temperature Coefficient: 50 ppm/°C ± 1.2 mV/°C 100 ppm/°C ± 8 mV/°C

Maximum Readback Capability: 65 to 70 V (typical) 260 V (typical)

EXTERNAL ANALOG PROGRAMMING (0 to 10 Vdc or 0 to 10 Vac)
Bandwidth: 10 kHz (3 db frequency)

Accuracy

Low Current Range: ± 4.5% ± 75 mA ± 3% ± 10 mA
High Current Range: ± 4.5% ± 250 mA ± 3% ± 20 mA
Voltage Range: ± 0.8% ± 200 mV ± 0.5% ± 150 mV

Temperature Coefficient

Current Range: 100 ppm/° ± 6 mA/°C 150 ppm/°C ± 1 mA/°C
Voltage Range: 100 ppm/°C ± 1 mV/°C 120 ppm/°C ± 10 mV/°C

EXTERNAL CURRENT MONITOR (0 TO 10 V):
Accuracy ± 4% ± 85 mA*
Temperature Coefficient 50 ppm/°C ± 6 mA/°C 100 ppm/°C ± 1 mA/°C
*referenced to Analog Common

EXTERNAL VOLTAGE MONITOR (0 TO 10 V):

Accuracy ± 0.25% ± 40 mV* 0.4% ± 240 mV*
Temperature Coefficient 50 ppm/°C ± 0.2 mV/°C 70 ppm/°C ±1.2 mV/°C
*referenced to Analog Common

MAXIMUM INPUT LEVELS

Current: 61.2 A* 10.2 A*
Voltage: 75 V 250 V
*programmable to lower limits.

DC FLOATING VOLTAGE (DC ISOLATION):

± 240 Vdc between + or - input binding post and chassis ground

DIGITAL INPUTS

Vlo: 0.9 V maximum at Ilo = -1 mA
Vhi: 3.15 V minimum (pull-up resistor on input)

DIGITAL OUTPUTS

Vlo: 0.72 V maximum at Ilo = 1 mA
Vhi: 4.4 V maximum at Ilo = -20 µA

INPUT CURRENT: 100 Vac - 400 mA
120 Vac - 350 mA
220 Vac - 200 mA
240 Vac - 180 mA

±

3% ± 10 mA*

14 General Information

Table 1-2. Supplemental Characteristics (continued)

Fuse: The ac input is protected by a fuse located in a module on the rear panel; 0.5AM for l00/120 Vac

input; 0.25AM for 220/240 Vac input.

Maximum VA: 60

Peak Inrush Current: 2.5 A (typical)

PROGRAMMABLE SLEW RATE: (For any given input transition, the time required will be either the total slew time
or a minimum transition time, whichever is larger. The minimum transition time increases when operating with input
currents under 1 AM (6060B) or 0.2 AM (6063B) and decreases with input currents over 20 A (6060B) or 2 A (6063B).
The following are typical values; ± 25% tolerance.)

Current Slew Rate:
Model 6060B (Ac performance specified from 3 to 60 V)

Rate # High Range Step Low Range Step Transition Time

1 1 A/ms 0.1 A/ms 8.0 ms
2 2.5 A/ms 0.25 A/ms 3.2 ms
3 5 A/ms 0.5 A/ms 1.6 ms
4 10 A/ms 1 A/ms 800 µs

5 25 A/ms 2.5 A/ms 320 µs
6 50 A/ms 5 A/ms 160 µs
7 0.1 A/µs 10 A/ms 80 µs
8 0.25 A/µs 25 A/ms 32 µs
9 0.5 A/µs 50 A/ms 16 µs
10 1 A/µs 0.1 A/µs 12 µs
11 2.5 A/µs 0.25 A/µs 12 µs
12 5 A/µs 0.5 A/µs 12 µs

Model 6063B (Ac performance specified from 3 to 240 V)

Rate # High Range Step Low Range Step Transition Time

1 0.17 A/ms 17 A/s 8.0 ms
2 0.42 A/ms 42 A/s 3.2 ms
3 0.83 A/ms 83 A/s 1.6 ms
4 1.7 A/ms 0.17 A/ms 800 µs

5 4.2 A/ms 0.42 A/ms 320 µs
6 8.3 A/ms 0.83 A/ms 160 µs
7 17 A/ms 1.7 A/ms 80 µs
8 42 A/ms 4.2 A/ms 32 µs
9 83 A/ms 8.3 A/ms 20 µs
10 0.17 A/µs 17 A/ms 20 µs
11 0.42 A/µs 42 A/ms 16 µs
12 0.83 A/µs 83 A/ms 16 µs

General Information 15

Table 1-2. Supplemental Characteristics (continued)

Voltage Slew Rate:

6060B (0 to 60V) 6063B (0 to 240V) Transition
Rate # Voltage Step Voltage Step Time*

1 1 V/ms 4 V/ms 8.0 ms
2 2.5 V/ms 10 V/ms 3.2 ms
3 5 V/ms 20 V/ms 1.6 ms
4 10 V/ms 40 V/ms 800 µs

5 25 V/ms 100 V/ms 320 µs
6 50 V/ms 200 V/ms 160 µs
7 0.1 V/µs 0.4 V/µs 100 µs
8 0.25 V/µs 1 V/µs 100 µs
9 0.5 V/µs 2 V/µs 100 µs

*Transition time is based on low capacitance current source.

Resistance Slew Rate

Low Range: Uses the value programmed for the voltage slew rate.
Middle and High Ranges: Uses the value programmed for the current slew rate.

TRANSIENT CURRENT OVERSHOOT (When programmed from 0A):

Model 6060B
Range Transient Current Level Current Slew Rate Overshoot*

60 A 6-60 A All slew rates 0
3 A I A/µs to 5 A/µs1%
3 A I A/ms to 0.5 A/µs0

6 A 6 A All slew rates 0
3 A 0.25 A/µs and 0.5 A/µs1%
3 A 0.1 A/ms to 0.1 A µs0

Model 6063B
Range Transient Current Level Current Slew Rate Overshoot*

10A 2-10 A All slew rates 0

0.5 A 0.17 A/µs to 0.83 A/µs5%

0.5 A 0.17 A/ms to 42 A/ms 0
1 A 0.83 A/µs1%
1 A 0.17 A/ms to 0.17 A/µs0

1 A 0.5 A 83 A/ms 4%

0.5 A 17 A/s to 17 A/ms 0
1 A All slew rates 0

*All overshoot values assume a total inductance of 1 µH, or less, in the load leads connected to the D.U.T. For Model
6060B, overshoot may be higher during first five seconds of programming if the unit has been operating at full current.

16 General Information

Table 1-2. Supplemental Characteristics (continued)

SOURCE TURN-ON CURRENT OVERSHOOT (In CC and CR modes when connected to power supplies with

voltage rise times of greater than 500 µs)

6060B 6063B
<10% <5%

PROGRAMMABLE SHORT CIRCUIT

0.033 ohm (0.02 ohm typ) 0.20 ohm (0.10 ohm typ)

PROGRAMMABLE OPEN CIRCUIT
20 k (typical) 80 k (typical)

DRIFT STABILITY (Over an 8 hour interval)
Current: ± 0.03% ± 10 mA ± 0.03% ± 15 mA

Voltage: ± 0.01% ± 10 mV ± 0.01% ± 20 mV

REVERSE CURRENT CAPACITY

With unit on: 100 A 20 A
With unit off: 40 A 10 A

GPIB PROGRAMMING COMMAND PROCESSING TIME (Typical time required for a GPIB command to be

processed by the Electronic Load.)

70 ms

GPIB CAPABILITIES
SH1, AH1, T6, L4, SR1, RL1, DT1, DC1

WEIGHT

6.12 kg (13.5 lb) net; 8.16 kg (18 lb) shipping

DIMENSIONS

Width: 425.5 mm (16.75 in)
Height: 88.1 mm (3.5 in)
Depth: 346 mm (13.6 in), not including 50 mm for binding posts

General Information 17

2

Operation Overview

Introduction

The Electronic Load is used for design, manufacturing, and evaluation of dc power supplies, batteries, and power
components. The primary operating features of the Electronic Load are: constant current (CC) mode, constant voltage (CV)
mode, or constant resistance (CR) mode. The input can also be turned on or off (open circuit) or short circuited.

Other features include a built-in GPIB interface and a built-in pulse generator. Pulse mode allows dynamic testing of power
supplies and components, without giving the device under test time to heat up. This flexible mode provides three triggering
methods, allowing synchronization with a wide variety of events. A Save/Recall feature allows you to save up to 7 complete
instrument setups, one of which can be saved in non-volatile memory so that it is recalled automatically at power-on. Also
standard is GPIB readback of actual input voltage and current, and extensive protection and status reporting capability.

The Electronic Load contains a fan whose speed automatically increases or decreases as the heatsink temperature rises and
falls. This reduces the overall noise level because the fan does not run at maximum speed at all times.

The input power rating curve for the Electronic Load is shown in Table 1-1. Refer to the extended power paragraphs in this
section for a description of the power rating curves. Note that regardless of the power rating, input current is derated
linearly from 2 volts down to 0 volts.

If your application requires a greater power or current capacity than one Electronic Load can provide, Electronic Loads can
be connected in parallel in CC or CR mode.

Front Panel Description

The front panel includes a 12-character alphanumeric display, 11 status indicators, and three groups of keypads. Ordinarily
the alphanumeric display shows the input voltage and current. By using the
power, programming error codes, and protection-circuit status. If any protection circuits are active, that status will be
displayed first when you use the
you use the keypads.

The display also includes 11 annunciators that point to the 11 status labels printed on the front panel. These are: Constant
Current, Constant Resistance, Constant Voltage, Transient, Unregulated, Protection, Error, Shift, Remote, Address, and
Service ReQuest.

Three keys perform two functions, with the alternative function labeled in blue above the key. The alternative function is
selected by first pressing the blue (shift) key, which turns on the Shift annunciator and enables the alternative function.

key. The alphanumeric display shows what function is being performed when

Remote Programming

Commands sent to the Electronic Load via GPIB are decoded by the primary microprocessor, which detects syntax and
range errors. The primary processor also prescales data and maintains the status registers. Three commands have aliases
for compatibility with other HPSL instruments. MODE can also be called FUNCtion, INPut can also be called OUTPut,
and INSTrument can also be called CHANnel . OUTPut and INSTrument would typically be used if you want your
program to refer to the Electronic Load in terms of the device or instrument under test. When using the CHANnel
command, remember that the Electronic Load is always channel 1.

key you can sequentially display input

Operation Overview 19

Local/Remote Control

Local (front panel) control is in effect immediately after power is applied. The front panel keypad and display allow manual
control when the Electronic Load is used in bench test applications. Remote (computer) control goes into effect (front panel
Rmt annunciator is on) as soon as the Electronic Load receives a command via the GPIB. A built-in GPIB interface and
HPSL compatible commands allow control and readback of all functions when the Electronic Load is used in computer
controlled applications.

With remote control in effect, only the computer can control the Electronic Load; the front panel keypad has no effect. You
can, however, still use the front panel display to view the input voltage and current readings. You can return the Electronic
Load to local control from remote control by pressing
the local-lockout command has been received from the GPIB computer.

Details of local operation are covered in Chapter 4 and fundamentals of remote programming are given in Chapter 5.
Complete HPSL programming details are given in the Programming Reference Guide. The remaining paragraphs in this
chapter describe the operating modes, transient operation, protection features, and other operating features of the Electronic
Load.

. This will return the Electronic Load to local control, unless

Programmable Features

Modes of Operation

The three modes of operation are:

•

constant current (CC)

•

constant voltage (CV)

•

constant resistance (CR)

When programmed to a mode, the Electronic Load remains in that mode until the mode is changed or until a fault condition,

such as an overpower or overtemperature, occurs. When changing modes, the load’s input is disabled for approximately 6
milliseconds (non-conducting state) before the new mode is enabled. This insures that there will be minimum overshoots
when changing modes.

The current, resistance, and voltage mode parameters described in subsequent paragraphs can be programmed whether or
not the mode is presently selected. When a mode is selected via the front panel or via the GPIB, most of the associated
parameters will take effect at the input (exceptions are noted in the mode descriptions).

Constant Current CC (Mode)

In this mode, the load will sink a current in accordance with the programmed value regardless of the input voltage (see
Figure 2-1). The CC mode can be set with front panel keys(

(MODE:CURR command). The CC mode parameters are discussed in the following paragraphs.

Ranges

Current may be programmed in either of two overlapping ranges, a low range and a high range. The low range provides
better resolution at low current settings. The range can be set at the front panel (
the GPIB (CURR:RANG command). Any value in the low range selects the low range. Any value above the maximum of

the low range selects the high range. Changing the range affects the load in the same manner as changing modes; i.e., it
causes the input to go through a non-conducting state for approximately 0.2 milliseconds. Note that the values of the
present current settings may be automatically adjusted to fit the new range. For example, if 10 A is the present setting and
the 0 to 6 A range is then programmed, the current setting will automatically be changed to 6 A; see Chapter 4.

, , and ) or via the GPIB

,

and ENTRY keys) or via

20 Operation Overview

Immediate Current Level

The current level can be set at the front panel (
mode is the active mode, the new setting immediately changes the input at a rate determined by the slew setting (described
below). If the load is not in the CC mode, the new setting is saved for use when the mode is changed to CC.

Triggered Current Level

The current level can be preset (stored in the Electronic Load) allowing the input to be updated when a trigger is received
instead of immediately as previously described. The current level can only be preset via the GPIB (CURR:TRIG
command). The preset capability is not available at the front panel.

If the CC mode is the active mode, the preset current level will become the actual value and the input will be updated when
a trigger occurs. If the CC mode is not the active mode, the preset current level will become the actual value when a trigger
occurs but there will be no effect on the input until the CC mode becomes active. Once a level is triggered, subsequent
triggers will have no effect on the input unless another CURR:TRIG command is sent. The trigger sources available to the
Electronic Load are described later in this chapter. The Electronic Load has a status reporting capability to keep track of
pending triggers and other operating conditions. The status reporting capability is described in detail in the Programming
Reference Guide.

Transient Current Level

The transient current level can be set at the front panel (
(CURR:TLEV command). The transient current level determines the higher current level when transient operation
(described later in this chapter) is turned on. The load will switch between the main level and the transient level when
transient operation is turned on.

Software Current Limit

The Electronic Load allows the user to set a current limit from 0 to 102% of full scale via the GPIB (CURR:PROT
command), which will shut down the input if the current limit is exceeded beyond a programmable time delay. Note that the
software current limit is in effect for any mode of operation (not just the CC mode). The software current limit feature is
described later in this chapter under Protection Features.

Figure 2-1. Constant Current Mode

and ENTRY keys) or via the GPIB (CURR command). If the CC

, and ENTRY keys) or via the GPIB

Operation Overview 21

Slew Rate

Slew rate determines the rate at which the input level changes to a new programmed value. Slew rate can be set at the front
panel (
the immediate, triggered, and transient level changes previously described.

There are 12 discrete current slew rates within each slew-rate range. Any slew rate value can be sent to a load (there are no
upper and lower limits that would cause an error), and a load will automatically select one of the 12 rates that is closest to
the programmed value. The slew rate is rescaled to the closest fit in the 1-of-12 discrete steps if the current range is
changed.

Constant Resistance (CR) Mode

In this mode, the load will sink a current linearly proportional to the input voltage in accordance with the programmed
resistance (see Figure 2-2). The CR mode can be set at the front panel (

(MODE:RES command). The CR mode parameters are described in the following paragraphs.

, and ENTRY keys) or via the GPIB (CURR:SLEW command). This slew rate remains in effect for

,

and

keys) or via the GPIB

Figure 2-2. Constant Resistance Mode

Ranges

Resistance may be programmed in any of three overlapping ranges (low, middle, high). The range can be set at the front
panel (

the low range. Any value that is within the middle range and above the maximum low-range value selects the middle range.
Any value that is within the high range and above the maximum middle-range value selects the high range. Note that the
values of the present resistance settings may be automatically adjusted to fit within the new range.

Immediate Resistance Level

The resistance level can be set at the front panel (
mode is the active mode, the new setting immediately changes the input at a rate determined by the voltage or current slew
setting (see description below). If the load is not in the CR mode, the new setting is saved for use when the mode is changed
to CR.

, , and ENTRY keys) or via the GPIB (RES:RANG command). Any value in the low range selects

and ENTRY keys) or via the GPIB (RES command). If the CR

22 Operation Overview

Triggered Resistance Level

The resistance level can be preset (stored in the Electronic Load) allowing the input level to change when a trigger is
received instead of immediately as previously described. The resistance level can only be preset via the GPIB (RES:TRIG
command). The preset capability is not available at the front panel.

If the CR mode is the active mode, the preset resistance level will become the actual value and the input will be updated
when a trigger occurs. If the CR mode is not the active mode, the preset resistance level will become the actual value when
a trigger occurs but there will be no effect on the input until the CR mode becomes active. Once a level is triggered,
subsequent triggers will have no effect on the input unless another CURR:TRIG command is sent.

Transient Resistance Level

The transient resistance level can be set at the front panel (
(RES:TLEV command). The transient level and the main level are used in transient operation, which is described later in
this chapter. In the low resistance range, the transient level must be set to a higher resistance value than the main level.
However, in the middle and high resistance ranges, the transient level must be set to a lower resistance value than the main
level.

Slew Rate

Slew rate in resistance mode is not programmed in ohms/second. In the low resistance range, slew rate is programmed in
volts/second. Whatever value is programmed for the voltage slew rate is also used for the low resistance range.

In the middle and high resistance ranges, slew rate is programmed in amps/second. Whatever value is programmed for the
current slew rate is also used for the middle or high resistance ranges.

Constant Voltage (CV) Mode

In this mode, the load will attempt to sink enough current to control the source voltage to the programmed value (see Figure
2-3). The load acts as a shunt voltage regulator when operating in the CV mode. The CV mode can be set

at the front panel (
parameters are described in the following paragraphs.

Range

Voltage mode has only one range

, and keys) or via the GPIB (MODE:VOLT command). The CV mode

, and ENTRY keys) or via the GPIB

Figure 2-3. Constant Voltage Mode

Operation Overview 23

Immediate Voltage Level

The voltage level can be set at the front panel (
mode is the active mode, the new setting immediately changes the input level at a rate determined by the voltage slew
setting. If the load is not in the CV mode, the new setting is saved for use when the mode is changed to CV.

Triggered Voltage Level

The voltage level can be preset (stored in the Electronic Load) allowing the input level to change when a trigger is received
instead of immediately as previously described. The voltage level can only be preset via the GPIB (VOLT:TRIG)
command.

Transient Voltage Level

The transient voltage level can be set at the front panel (
(VOLT:TLEV command). The load input will switch between the main level and the transient level when transient
operation is turned on. The transient voltage level determines the higher voltage level.

Slew Rate

Slew rate determines the rate at which the voltage changes to a new programmed setting. Slew rate can be set at the front
panel (
the immediate, triggered and transient voltage level changes described above.

There are 12 discrete slew rates that can be programmed for CV Mode slew rate. Any slew-rate value can be sent to the load
(there are no upper and lower limits that would cause an error). The load will automatically select one of the 12 rates that is
closest to the programmed value. It is important to note that the fastest slew rates cannot be achieved because of bandwidth
limitations (refer to the specifications table).

Transient Operation

Transient operation enables the load to periodically switch between two load levels, as might be required for testing power
supplies. A power supply’s regulation and transient characteristics can be evaluated by monitoring the supply’s output
voltage under varying combinations of load levels, frequency, duty cycle, and slew rate. Transient operation can be turned

on and off at the front panel (
on transient operation, you should set the desired mode of operation as well as all of the parameters associated with transient
operation. Transient operation may be used in the CC, CR, or CV modes and can be continuous, pulsed, or toggled. Note
that the pulsed or toggled operation cannot be programmed from the front panel.

Continuous Transient Operation

In continuous operation, a repetitive pulse train switches between two load levels. Continuous transient operation is
selected via the GPIB using the TRAN:MODE CONT command. For front panel operation, continuous transient

operation is automatically selected when transient operation is turned on(

The two load levels in the transient operation are the previously described main level (immediate or triggered) and transient
level for current, resistance, or voltage. The rate at which the level changes is determined by the slew rate (see slew rate
descriptions for CV, CR, or CV mode as applicable). In addition, the frequency and duty cycle of the continuous pulse train
are programmable.

The frequency can be set from 0.25 to 10000 Hz at the front panel (
(TRAN:FREQ command) The duty cycle can be set from 3% to 97% (0.25 Hz to 1 kHz) or from 6% to 94% (above 1
kHz) at the front panel(

, , and ENTRY keys) or via the GPIB (VOLT:SLEW command). This slew rate remains in effect for

key) or via the GPIB (TRAN ON and TRAN OFF commands). Before you turn

and ENTRY keys) or via the GPIB (TRAN:DCYC command).

and ENTRY keys) or via the GPIB (VOLT command). If the CV

, and ENTRY keys) or via the GPIB

key).

and ENTRY keys) or via the GPIB

24 Operation Overview

For example, assume that the CC mode is active, the slew rate is at the default setting (maximum rate), and the applicable
transient operation parameters have been set as follows:

HPSL Command

TRAN:MODE CONT
CURR 5
CURR:TLEV 10
TRAN:FREQ 1000
TRAN:DCYC 40
TRAN ON

Figure 2-4 shows the waveform that would result in this example. The load input current will slew to and remain at 10 amps
for 40% of the period (400 µs), then slew to and remain at 5 amps for the remaining 60% (600 µs) of that cycle.

Description

Sets continuous operation.
Sets main current level to 5 amps.
Sets transient current level to 10 amps.
Sets transient generator frequency to 1 kHz.
Sets transient generator duty cycle to 40%.
Turns on transient operation.

Figure 2-4. Continuous Transient Operation

The load starts conduction at the main level (in this case 5 amps). When transient operation is turned on and at a time
specified by the frequency setting the input level starts increasing at a rate determined by the slew rate. When the value
specified by the transient level setting is reached, it stays there for the remainder of the time determined by the frequency
and duty cycle settings. After this time has elapsed, the input level decreases to the main level again at the rate specified by
the slew setting and stays there for the remainder of the period prescribed by the frequency setting.

Pulsed Transient Operation

Pulsed transient operation is similar to continuous operation with the following exceptions:

a. In order to get a pulse, an explicit trigger is required. The trigger can be an external trigger signal received via

the TRIGGER input on the rear panel, the GPIB GET function, the *TRG common HPSL command, or the TRIG
subsystem HPSL command.

b. One pulse results from each trigger. Therefore, frequency cannot be programmed. The main level, transient

level, and slew rate are programmed as described for continuous operation. The pulse width is programmable from

0.00005 to 4 seconds via the GPIB (TRAN:TWID command). Pulsed transient operation cannot be programmed at
the front panel.

c. There may be a delay between the generation of the trigger and the appearance of the pulse at the load’s input.

For pulse widths of 17 ms or greater, delay is less than 1.6% of the pulse width. For pulse widths of less than 17 ms,
delay is less than 4% of the pulse width.

In this example, assume that the CC mode is active, the slew rate is at the factory default setting (maximum rate), an external
trigger input is connected to the Electronic Load’s rear panel, and the applicable transient operation parameters have been
set as follows:

Operation Overview 25

HPSL Command Description

TRIG:SOUR EXT Selects the external trigger input.
TRAN:MODE PULS Selects pulsed transient operation.
CURR 5 Sets main current level to 5 amps.
CURR:TLEV 10 Sets transient current level to 10 amps.
TRAN:TWID .001 Sets pulse width to 1 millisecond.
TRAN ON Turns on transient operation.

Figure 2-5 shows the waveform that would result in this pulsed transient operation example. The Electronic Load starts
conduction at the main current level setting (5 amps). When the transient mode is turned on and an external trigger signal is
received, the input level starts increasing at a rate determined by the slew rate. When the value specified by the transient
level setting (10 amps) is reached, it stays there for the remainder of the time determined by the pulse width setting
(1 millisecond). After this time has elapsed, the input level decreases to the main level again at the rate specified by the
slew setting and remains there until another trigger is received. Any triggers that occur during the time the transient level is
in effect will be ignored.

Toggled Transient Operation

Toggled transient operation causes the load input to alternate between two predefined levels as in continuous operation
except that the transient points are controlled by explicit triggers instead of the internal transient generator. As in pulsed
transient operation, the trigger signal can be an external trigger signal, the GPIB GET function, the *TRG command, or the
TRIG command. Note that toggled transient operation can only be programmed via the GPIB (TRAN:TOGG command);
it cannot be programmed at the front panel.

In this example, assume that the CC mode is active, the slew rate is at the factory default setting (maximum rate), an external
trigger input signal is connected to the Electronic Load’s rear panel, and the applicable transient operation parameters have
been set as follows:

HPSL Command Description

TRIG:SOUR EXT Selects the external trigger input source.
TRAN:MODE TOGG Selects toggled operation.
CURR 5 Sets main current level to 5 amps.
CURR:TLEV 10 Sets transient current level to 10 amps.
TRAN ON Turns on transient operation.

Figure 2-5. Pulsed Transient Operation

26 Operation Overview

Figure 2-6 shows the waveform that would result for this toggled transient operation example. Operation is similar to that
described for continuous and pulse operation, except that each time a trigger is received the input alternates between the
main and transient current levels.

Figure 2-6. Toggled Transient Operation

Triggered Operation

The Electronic Load has various triggering modes to allow synchronization with other test equipment or events. As
described previously, triggering can be used for the following applications:

Triggering a preset level

Triggering a transient pulse

Toggling

Three triggering methods are available over the GPIB: the GET function, the *TRG common HPSL command, and the
TRIG subsystem HPSL command (refer to Programming Reference Guide). The HPSL TRIG subsystem allows you to

select the TRIG command as the trigger source. There is also a TRIGGER connector on the rear panel for external trigger
inputs. Triggering cannot be done via the front panel.

*TRG and the TRIG command are both synchronous with other commands; that is, the load is not triggered until pending
operations are completed. GET and external triggers are all asynchronous; that is, the loads are triggered as soon as the
trigger signal is received.

The rear-panel TRIGGER connector also provides a trigger output signal. This signal is generated synchronously with the
trigger signal sent by the load. The trigger output signal can be used to trigger an external device such as an oscilloscope,
DVM, or another Electronic Load.

The Electronic Load has a status reporting capability to keep track of trigger operations. Refer to ’Status Reporting’ in the

Agilent Electronic Loads Programming Reference Guide.

Slew Rate And Minimum Transition Time

Slew rate is defined as the change in current or voltage over time. A programmable slew rate allows a controlled transition
from one load setting to another to minimize induced voltage drops on inductive power wiring, or to control induced
transients on a test device (such as would occur during power supply transient response testing).

Transfers all pending preset levels to the actual level. For the presently active mode, the
new level appears at the input. For the modes which are not presently active, the preset
levels will not take effect at the input until the applicable mode becomes active.

Generates a transient pulse of programmable width when pulsed transient operation is in
effect.

Changes the input between the main level and the transient level when toggled transient
operation is in effect.

Operation Overview 27

In cases where the transition from one setting to another is large, the actual transition time can be calculated by dividing the
voltage or current transition by the slew rate. The actual transition time is defined as the time required for the input to
change from 10% to 90% or from 90% to 10% of the programmed excursion. In cases where the transition from one setting
to another is small, the small signal bandwidth of the load limits the minimum transition time for all programmable slew
rates. Because of this limitation, the actual transition time is longer than the expected time based on the slew rate, as shown
in Figure 2-7.

Therefore, both minimum transition time and slew rate must be considered when determining the actual transition time. This
is shown in Figure 2-8 for the twelve programmable slew rates in current mode operation. The actual transition time will be
either the total slew time (transition divided by slew rate), or the minimum transition time, whichever is longer.

In voltage mode, all minimum transition times are based on a low-capacitance current source. These transition times are
affected by capacitive loading of the inputs. For example, a capacitance of 2.2 microfarads increases the 85 microsecond
minimum transition time (shown in the specifications table) to 110 microseconds. Therefore, no graph is provided for
minimum transition time and slew rate in voltage mode operation.

In resistance mode, the low resistance range uses the slew rate that has been programmed for voltage mode. The middle
resistance range uses the slew rate that has been programmed for the high current range. The high resistance range uses the
slew rate that has been programmed for the low current range.

Input Current, Voltage, and Power Measurement

Each load’s input current, voltage, and power can be measured at the front panel (
command). With local (front panel) control in effect, pressing

current input values, the computed power value, and various status conditions for the selected channel.

With remote control in effect, a load may be instructed to measure its dc input voltage, current, or power by sending the
appropriate query command (e.g. MEAS:CURR). The results will be read back when the load is addressed to talk.
Voltage and current measurements are performed with approximately 12-bit resolution of full scale ratings. Power is
computed from this information.

Figure 2-7. Risetime Transition Limitation

key) or via the GPIB (MEAS

will continually step the display through voltage and

28 Operation Overview

Short On/Off

A load can simulate a short circuit at its input by turning the load on with full-scale current. The short circuit can be toggled
on/off at the front panel (
change uses the slew rate setting of the active mode and range.

key) or via the GPIB (INPUT:SHORT ON|OFF command). The short on/off

Figure 2-8. Transition Times and Slew Rates

The actual value of the electronic short is dependent on the mode and range that are active when the short is turned on. In
CV mode, it is equivalent to programming zero volts. In CC mode, it is equivalent to programming full-scale current for the
present CC range. In CR mode, it is equivalent to programming the minimum resistance for the present resistance range.

Note that turning the short on in CV mode may cause the load to draw so much current that the software current limit
operates, which may turn the input off.

Turning the short circuit on does not affect the programmed settings, and the input will return to the previously programmed
values when the short is turned off.

Pressing the Short on/off key with certain user applications may cause damage to the equipment being
tested, which may result in personal injury. Contact your Agilent Sales and Service office if you need
to have the Short on/off key disabled.

Operation Overview 29