OPERATING MANUAL
Analog Programmable
DC POWER SUPPLIES
Agilent Technologies
Series 654xA, 655xA, 657xA
SERIAL NUMBERS
AGILENT Model 6541A;3215A-00108 and Above*
AGILENT Model 6542A;3221A-00113 and Above*
AGILENT Model 6543A;3218A-00113 and Above*
AGILENT Model 6544A;3219A-00113 and Above*
AGILENT Model 6545A;3215A-00108 and Above*
AGILENT Model 6551A;3207A-00103 and Above*
AGILENT Model 6552A;3203A-00103 and Above*
AGILENT Model 6553A;3202A-00103 and Above*
AGILENT Model 6554A;3205A-00103 and Above*
AGILENT Model 6555A:3209A-00108 and Above*
AGILENT Model 6571A;3206A-00103 and Above*
AGILENT Model 6572A;3216A-00108 and Above*
AGILENT Model 6573A;3223A-00108 and Above*
AGILENT Model 6574A;3230A-00113 and Above*
AGILENT Model 6575A;3242A-00113 and Above*
* For instruments with higher serial numbers, a change page may be included.
S1
Agilent Part No. 5959-3374
Microfiche Part No. 5959-3375
Printed in USA: October, 1993
Reprinted: 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.
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 of this instrument. Failure to
comply with these precautions or with specific warnings elsewhere in this guide 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.
GENERAL.
This product is a Safety Class 1 instrument (provided with a protective earth terminal). The protective features of this product may be
impaired if it is used in a manner not specified in the operation instructions.
Any LEDs used in this product are Class 1 LEDs as per IEC 825-l.
ENVIRONMENTAL CONDITIONS
All instruments are intended for indoor use in an installation category II, pollution degree 2 environment. They are 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.
BEFORE APPLYING POWER.
Verify that the instrument is set to match the available line voltage.
GROUND THE INSTRUMENT.
To minimize shock hazard, the instrument chassis and cover must be connected to an electrical ground. The instrument must be
connected to the ac power mains through a three-conductor power cable, with the third 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. 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 (earth 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 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 line rating label
may cause leakage currents in excess of 5.0 mA peak.
SAFETY SYMBOLS.
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.
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.
Instruments that appear damaged or defective should be made inoperative and secured against unintended operation until they can be
repaired by qualified service personnel.
3
SAFETY SYMBOL DEFINITIONS
Symbol
Description
Alternating current
Description
Terminal for Line conductor on permanently
installed equipment
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.)
Off (supply)
Direct current
Symbol
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.
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.
* Sound Pressure Lp <70 dB(A) *At Operator Position * Normal Operation * According to EN 27779 (Type Test).
Printing History
The edition and current revision of this manual are indicated below. Reprints of this manual containing minor corrections
and updates may have the same printing date. Revised editions are identified by a new printing date. A revised edition
incorporates all new or corrected material since the previous printing date. Changes to the manual occurring between
revisions are covered by change sheets shipped with the manual. In some cases, the manual change applies only to specific
instruments. Instructions provided on the change sheet will indicate if a particular change applies only to certain
instruments.
© Copyright 1992, 1993 Agilent Technologies Inc.
Edition 1
April 1992
.................... January 1993
.................... October 1993
reprinted ...... 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.
4
DECLARATION OF CONFORMITY
according to ISO/IEC Guide 22 and EN 45014
Manufacturer’s Name:
Agilent Technologies
Manufacturer’s Address:
140 Green Pond Road
Rockaway, New Jersey 07866
U.S.A.
declares that the Product
Product Name:
a) Single Output System Power Supply
b) General Purpose Power Supply
Model Number:
a) AGILENT 6641A, 6642A, 6643A, 6644A, 6645A
b) AGILENT 6541A, 6542A, 6543A, 6544A, 6545A
conforms to the following Product Specifications:
Safety:
IEC 1010-1:1990+A1(1992)/EN61010-1:1993
EMC:
CISPR 11:1990 / EN 55011:1991 - Group 1 Class B
IEC 801-2:1991 / EN 50082-1:1992 - 4 kV 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 Signal Lines
1 kV Power Lines
Supplementary Information:
The product herewith complies with the requirements of the Low Voltage Directive
73/23/EEC//93/68/EEC and the EMC Directive 89/336/EEC and carries the CE-marking accordingly.
Note 1: The product family was introduced prior to 12/93.
New Jersey
Location
December 1, 1998
Date
Bruce Krueger / 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:+49-7031-14-3143)
5
DECLARATION OF CONFORMITY
according to ISO/IEC Guide 22 and EN 45014
Manufacturer’s Name:
Agilent Technologies
Manufacturer’s Address:
140 Green Pond Road
Rockaway, New Jersey 07866
U.S.A.
declares that the Product
Product Name:
a) Single Output System Power Supply
b) General Purpose Power Supply
Model Number:
a) AGILENT 6651A, 6652A, 6653A, 6654A, 6655A
b) AGILENT 6551A, 6552A, 6553A, 6554A, 6555A
conforms to the following Product Specifications:
Safety:
IEC 1010-1:1990+A1(1992)/EN61010-1:1993
EMC:
CISPR 11:1990 / EN 55011:1991 - Group 1 Class B
IEC 801-2:1991 / EN 50082-1:1992 - 4 kV 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 Signal Lines
1 kV Power Lines
Supplementary Information:
The product herewith complies with the requirements of the Low Voltage Directive
73/23/EEC//93/68/EEC and the EMC Directive 89/336/EEC and carries the CE-marking accordingly.
Note 1: The product family was introduced prior to 12/93.
New Jersey
Location
December 1, 1998
Date
Bruce Krueger / 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:+49-7031-14-3143)
6
DECLARATION OF CONFORMITY
according to ISO/IEC Guide 22 and EN 45014
Agilent Technologies
Manufacturer’s Name:
Manufacturer’s Address:
140 Green Pond Road
Rockaway, New Jersey 07866
U.S.A.
declares that the Product
Product Name:
a) Single Output System Power Supply
b) General Purpose Power Supply
Model Number:
a) AGILENT 6671A, 6672A, 6673A, 6674A, 6675A
b) AGILENT 6571A, 6572A, 6573A, 6754A, 6575A
conforms to the following Product Specifications:
Safety:
IEC 1010-1:1990+A1(1992)/EN61010-1:1993
EMC:
CISPR 11:1990 / EN 55011:1991 - Group 1 Class B
IEC 801-2:1991 / EN 50082-1:1992 - 4 kV 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 Signal Lines
1 kV Power Lines
Supplementary Information:
The product herewith complies with the requirements of the Low Voltage Directive
73/23/EEC//93/68/EEC and the EMC Directive 89/336/EEC and carries the CE-marking accordingly.
Note 1: The product family was introduced prior to 12/93.
New Jersey
Location
December 1, 1998
Date
Bruce Krueger / 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:+49-7031-14-3143)
7
Table of Contents
1.
General Information
Introduction ................................................................................................................................................11
Safety Considerations.................................................................................................................................11
Instrument Identification ............................................................................................................................11
Options .......................................................................................................................................................11
Accessories.................................................................................................................................................12
Description .................................................................................................................................................12
Front Panel Programming........................................................................................................................13
Analog Programming ..............................................................................................................................13
Output Characteristic...............................................................................................................................13
Specifications and Supplemental Characteristics .......................................................................................13
2.
Installation
Inspection ...................................................................................................................................................27
Damage....................................................................................................................................................27
Items Supplied.........................................................................................................................................27
Location and Cooling .................................................................................................................................27
Bench Operation ....................................................................................................................................27
Rack Mounting ........................................................................................................................................27
Temperature Performance .......................................................................................................................28
Input Power Source ....................................................................................................................................28
Series 654xA and 655xA Supplies ..........................................................................................................28
Series 657xA Supplies.............................................................................................................................28
3.
Turn-On Checkout
Introduction ................................................................................................................................................31
Preliminary Checkout.................................................................................................................................31
Series 654xA and 655xA Supplies ..........................................................................................................31
Series 657xA Supplies.............................................................................................................................31
Power-On Checkout ...................................................................................................................................32
Output Checkout.........................................................................................................................................32
Shifted Keys ............................................................................................................................................32
Backspace Key ........................................................................................................................................32
Setting the Output Voltage ......................................................................................................................32
Setting the Output Current.......................................................................................................................32
Save/Recall Checkout.................................................................................................................................35
In Case of Trouble......................................................................................................................................35
Line Fuse .................................................................................................................................................35
Series 654xA and 655xA Supplies .......................................................................................................35
Series 657xA Supplies..........................................................................................................................36
Error Messages ........................................................................................................................................36
Selftest Errors .......................................................................................................................................37
Runtime Error Messages ......................................................................................................................38
4.
User Connections and Considerations
Rear Panel Connections..............................................................................................................................39
Output Connectors...................................................................................................................................39
Series 654xA and 655xA Supplies .......................................................................................................39
Series 657xA Supplies..........................................................................................................................39
Analog Connector...................................................................................................................................39
8
Table of Contents (continued)
Wire Size Selection .................................................................................................................................41
Output Isolation.......................................................................................................................................42
Load Considerations...................................................................................................................................43
Capacitive Loads .....................................................................................................................................43
Inductive Loads .......................................................................................................................................43
Multiple Loads .......................................................................................................................................44
Local Voltage Sensing................................................................................................................................44
Series 654xA and 655xA Supplies ..........................................................................................................44
Series 657xA Supplies.............................................................................................................................44
Remote Voltage Sensing ...........................................................................................................................45
Setting Up Remote Sense Operation .......................................................................................................45
Series 654xA and 655xA Supplies .......................................................................................................45
Series 657xA Supplies..........................................................................................................................45
Connecting the Sense Leads ....................................................................................................................45
CV Regulation.........................................................................................................................................45
Series 654xA and 655xA Supplies .......................................................................................................45
Series 657xA Supplies..........................................................................................................................45
Output Rating ..........................................................................................................................................45
Output Noise ...........................................................................................................................................46
Stability ................................................................................................................................................46
Series 657xA Network ......................................................................................................................46
Operating Considerations ...........................................................................................................................47
Auto-Parallel Operation ..........................................................................................................................47
Auto-Parallel Wiring ............................................................................................................................47
General Auto-Parallel...........................................................................................................................48
Series 654xA and 655XA Auto-Parallel Programming........................................................................48
Series Operation ......................................................................................................................................49
External Voltage Control.........................................................................................................................49
Programming Series 654xA and 655xA Supplies ................................................................................50
Programming Series 657xA Supplies ...................................................................................................51
OVP Considerations ................................................................................................................................51
Remote Sensing ....................................................................................................................................51
Battery Charging ..................................................................................................................................51
Series 654xA and 655xA Load Capacitance ........................................................................................51
5.
Front Panel Operation
Introduction ................................................................................................................................................53
Getting Acquainted.....................................................................................................................................53
Programming the Output ............................................................................................................................56
Introduction .............................................................................................................................................56
Establishing Initial Conditions ................................................................................................................56
Programming Voltage .............................................................................................................................57
Programming Current..............................................................................................................................57
CV Mode vs. CC Mode ...........................................................................................................................58
Programming Overvoltage Protection .....................................................................................................58
Programming Overcurrent Protection......................................................................................................59
Unregulated Operation ............................................................................................................................60
Saving and Recalling Operating States.......................................................................................................60
Normal Operation....................................................................................................................................60
Turn-On Operation ..................................................................................................................................60
9
Table of Contents (continued)
A.
Calibration
Introduction ................................................................................................................................................63
Equipment ..................................................................................................................................................63
General Procedure ......................................................................................................................................63
Parameters Calibrated..............................................................................................................................63
Equipment Connections...........................................................................................................................64
Performing the Calibration ........................................................................................................................64
Entering the Calibration Values ..............................................................................................................64
Saving the Calibration Constants.............................................................................................................64
Changing the Calibration Password........................................................................................................64
Disabling the Calibration Mode ..............................................................................................................66
Calibration Error Messages .....................................................................................................................66
B.
Line Voltage Conversion
Series 654xA and 655xA Power Supplies ..................................................................................................67
Series 657xA Power Supplies ....................................................................................................................68
Index
.......................................................................................................................................................................69
AGILENT Sales and Support Office ...................................................................................................................75
10
1
General Information
Introduction
This is the operating manual for your Agilent Series 654xA, 655xA, and 657xA power supplies. Unless otherwise stated, the
information in this manual applies to all models in the series. These supplies are the analog-programmable counterparts of
the Agilent Series 664xA, 665xA, and 667xA GPIB System power supplies.
Safety Considerations
This power supply is a Safety Class 1 instrument, which means it has a protective earth terminal. That terminal must be
connected to earth ground through a power source equipped with a 3-wire ground receptacle. Refer to the Safety Summary
page at the beginning of this manual for general safety information. Before installation or operation, check the power supply
and review this manual for safety warnings and instructions. Safety warnings for specific procedures are located at
appropriate places in the manual.
Instrument Identification
The power supply is identified by a unique two-part serial number, such as 3343A 00177. The first part, or prefix, is a
number-letter combination that provides the following information:
3343 The year and week of manufacture or last significant design change. Add 1960 to the first two digits to determine
the year. For example, 33=1993, 34=1994, etc. The last two digits specify the week of the year (43 = the 43rd
week).
A
The letter indicates the country of manufacture, where A = USA.
Options
Option
l00
200
220
230
240
831
832
834
841
842
843
List of Options
Description
Input power 100 Vac, nominal
Input power 200 Vac, nominal
Input power 220 Vac, nominal
Input power 230 Vac, nominal
Input power 240 Vac, nominal
Power cord, 12 AWG, UL listed. CSA certified, without plug
Power cord, 4 mm2, harmonized, without plug
Power cord, 10 AWG, UL listed, CSA certified, without plug
Power cord, 12 AWG, UL listed, CSA certified, with NEMA 6-20P
20A/250V plug
Power cord, 4 mm2, harmonized, with IEC 309 32A/220V plug
Power cord, 12 AWG, UL listed, CSA certified, with JIS C8303
25A/250V plug
Used with Agilent Series
654xA
X
655xA
X
657xA
X
X
X
X
X
X
X
X
X
X
X
X
X
General Information 11
List of Options (continued)
Description
Option
844
Used with Agilent Series
Power cord, 10 AWG, UL listed, CSA certified, with NEMA L6-30P
30A/250V locking plug
Rack mount kit (Agilent 5062-3974)
Rack mount kit (Agilent 5062-3977)
Rack mount kit with handles (Agilent 5062-3975)
Rack mount kit with handles (Agilent 5062-3983)
Service Manual with extra operating manual
908
909
910
X
X
X
X
X
X
X
X
X
X
Accessories
Agilent No.
1494-0058
1494-0059
Description
Heavy duty slide mount kit for Series 657xA
Standard slide mount kit for Series 654xA/655xA
Description
These units form a family of unipolar, analog programmable power supplies organized as follows:
Family
Series 654xA
Series 655xA
Series 657xA
Power
200 W
500 W
2000 W
Models
Agilent 6541A, 6542A, 6543A 6544A, 6545A
Agilent 6551A, 6552A, 6553A, 6554A, 6555A
Agilent 6571A, 6572A, 6573A, 6574A, 6575A
This family is similar in performance to the corresponding GPIB system power supplies.
Analog Family
Agilent 654xA
Agilent 655xA
Agilent 657xA
Corresponding GPIB Family
Agilent 664xA
Agilent 665xA
Agilent 667xA
Each power supply is programmable locally from the front panel or remotely via a rear-panel analog control port.
Operational features include:
•
•
•
•
•
•
•
•
•
•
Constant voltage (CV) or constant current (CC) output over the rated output range.
Built-in overvoltage (OV), overcurrent (OC), and overtemperature (OT) protection.
Automatic turn-on selftest.
Pushbutton nonvolatile storage and recall of up to 5 operating states.
Local or remote sensing of output voltage.
Auto-parallel operation for increased total current.
Series operation for increased total voltage.
Analog input for remote programming of voltage and current.
Voltage output for external monitoring of output current.
User calibration from the front panel.
Front Panel Programming
12
General Information
The front panel has both rotary (RPG) and keypad controls for setting the output voltage and current. The panel display
provides digital readouts of the output voltage and current. Other front panel controls permit:
•
•
•
•
•
Enabling or disabling the output.
Setting the overvoltage protection (OVP) trip voltage.
Enabling or disabling the overcurrent protection (OCP) feature.
Saving and recalling operating states.
Calibrating the power supply.
Analog Programming
The power supply has an analog port for remote programming. The output voltage and/or current of the power supply may
be controlled by d-c programming voltages applied to this port. The port also provides a monitor output that supplies a d-c
voltage proportional to the output current.
Output Characteristic
General
The power supply can operate in either CV (constant voltage) or CC (constant current) over its voltage and current ratings
(see “Performance Specifications”). The operating locus is shown by the output Characteristic Curve in “Supplemental
Characteristics”. The operating point is determined by the voltage setting (Vs), the current setting (Is), and the load
impedance. Two operating points are shown. Point 1 is defined by the load line cutting the operating locus in the
constant-voltage region. This region defines the CV mode. Point 2 is defined by the load line cutting the operating locus in
the constant-current region. This region defines the CC mode.
Downprogramming
The power supply can sink current for more rapid down programming in the CV mode. For Series 654xA and 655xA
supplies, this capability is defined by the second quadrant area (-Is) of the Output Characteristic Curve. These supplies can
sink about 20% of their maximum rated positive output current. For Series 657xA power supplies, this is an uncharacterized
current-sinking area that provides a limited downprogramming capability.
Specifications and Supplemental Characteristics
Table 1-1 lists the specifications and supplemental characteristics of the Series 654xA and 655xA power supplies. Table 1-2
lists the specifications and supplemental characteristics for the Series 657xA power supplies. Specifications are warranted
over the specified temperature range. Supplemental characteristics are not warranted but are descriptions of performance
determined either by design or type testing.
General Information 13
Table 1-1a. Performance Specifications for Series 654xA and 655xA (Note 1)
Parameter
Agilent Model Number and Parameter Value
Specifications are warranted over the temperature range 0 to 55° C with a resistive load and the output connected for local
sensing.
Output Ratings
Voltage:
6541A/6551A
6542A/6552A
6543A/6553A
6544A/6554A
6545A/6555A
0-8V
0 - 20 V
0 - 35 V
0 - 60 V
0 - 120 V
Current:*
6541A
6542A
6543A
6544A
6545A
0 - 20 A
0 - 10 A
0-6A
0 - 3.5 A
0 - 1.5 A
6551A
6552A
6553A
6554A
6555A
0 - 50 A
0 - 25 A
0 - 15 A
0-9A
0-4A
*Derate the output current 1% per °C from 40° C to 55° C.
Front Panel Programming Accuracy (@ 25° ± 5 °C)
6541A/6551A
6542A/6552A
6543A/6553A
6544A/6554A
6545A/6555A
0.06% +5 mV
0.06% +10 mV
0.06% +15 mV
0.06% +26 mV
0.06% +51 mV
Voltage:
Current:*
6541A
6542A
6543A
6544A
6545A
0.l4 % +26mA 0.l4 % +13mA
0.l4 % +7mA
0.l4 % +4mA
0.l4 % +2mA
6551A
6552A
6553A
6554A
6555A
0.l5 % +60mA 0.l5 % +25mA 0.l5 % +13mA
0.l5 % +8mA
0.l5 % +4mA
Ripple & Noise (from 20 Hz to 20 MHz with outputs ungrounded, or with either output terminal grounded)
Constant Voltage (rms):
6541A/6551A
6542A/6552A
6543A/6553A
6544A/6554A
6545A/6555A
300 µV
300 µV
400 µV
500 µV
700 µV
Constant Voltage (p-p):
6541A/6551A
6542A/6552A
6543A/6553A
6544A/6554A
6545A/6555A
3 mV
3 mV
4 mV
5 mV
7 mV
Constant Current (rms):
6541A
6542A
6543A
6544A
6545A
10 mA
5 mA
3 mA
1.5 mA
1 mA
6551A
6552A
6553A
6554A
6555A
25 mA
10 mA
5 mA
3 mA
2 mA
Readback Accuracy (with respect to actual output @ 25° C ± 5 °C)
Voltage:
6541A/6551A
6542A/6552A
6543A/6553A
6544A/6554A
6545A/6555A
+Current
-Current
0.07% +6 mV
0.07% +15 mV
0.07% +25 mV
0.07% +40 mV
6541A
6542A
6543A
6544A
6545A
0.15% +26 mA
0.15% +13 mA
0.15% +6.7 mA
0.15% +4.1 mA
0.15% +1.7 mA
6551A
6552A
6553A
6554A
6555A
0.15% +67 mA
0.15% +26 mA
0.15% +15 mA
0.15% +7 mA
0.15% +3 mA
6541A
6542A
6543A
6544A
6545A
0.35% +40 mA
0.35% +20 mA
0.35% +12 mA
0.35% +6.8 mA
0.35% +2.9 mA
6551A
6552A
6553A
6554A
6555A
0.35% +100 mA
0.35% +44 mA
0.35% +24 mA
0.35% +15 mA
0.35% +7 mA
Load Regulation (change in output voltage or current for any load change within ratings)
Voltage:
6541A/6551A
6542A/6552A
6543A/6553A
6544A/6554A
1 mV
2 mV
3 mV
4 mV
Current:
6541A
6542A
6543A
6544A
1 mA
0.5 mA
0.25 mA
0.25 mA
6551A
6552A
6553A
6554A
2 mA
1 mA
0.5 mA
0.5 mA
Line Regulation (change in output voltage or current for any line change within ratings)
Voltage:
6541A/6551A
6542A/6552A
6543A/6553A
6544A/6554A
0.5 mV
0.5 mV
1 mV
1 mV
Current:
6541A
6542A
6543A
6544A
1 mA
0.5 mA
0.25 mA
0.25 mA
6551A
6552A
6553A
6554A
2 mA
1 mA
0.75 mA
0.5 mA
14
General Information
0.07% +80 mV
6545A/6555A
5 mV
6545A
0.25 mA
6555A
0.5 mA
6545A/6555A
2 mV
6545A
0.25 mA
6555A
0.5 mA
Table 1-1a. Performance Specifications for Series 654xA and 655xA (continued)
Parameter
Agilent Model Number and Parameter Value
Transient Response Time
< 100 µs for the output voltage to recover to its previous level (within 0.1% of the
rated voltage or 20 mV, whichever is greater) following any step change in load
current up to 50% of the rated current.
AC Input Ratings (selectable via internal switching - see Appendix B)
Nominal line voltage
100,120,220,240 Vac:
-13%, +6 %
230 Vac:
-10%, +10%
Frequency range:
47-63 Hz
Output Terminal Isolation
±240 Vdc (maximum, from chassis ground)
Notes 1: For Supplemental Characteristics, see Table 1-1b.
Table 1-1b. Supplemental Characteristics for Series 654xA and 655xA (Note 1)
Parameter
Agilent Model Number and Parameter Value
Output Programming Range (maximum programmable values)
Voltage:
Overvoltage Protection:
Current:
Average Resolution
Voltage:
Current:
Overvoltage Protection:
Accuracy
Overvoltage Protection:
Analog Programming (VP):*
Analog Programming (IP):*
Current Monitor (+IM):*
6541A/6551A
8.190 V
6541A/6551A
8.8 V
6541A
20.475 A
6551A
51.88 A
6542A/6552A
20.475 V
6542A/6552A
22.0 V
6542A
10.237 A
6552A
25.594 A
6543A/6553A
35.831 V
6543A/6553A
38.5 V
6543A
6.142 A
6553A
15.356 A
6544A/6554A
61.425 V
6544A/6554A
66.0 V
6544A
3.583 A
6554A
9.214 A
6545A/6555A
122.85 V
6545A/6555A
132.0 V
6545A
1.535 A
6555A
4.095 A
6541A/6551A
2 mV
6541A
6 mA
6551A
15 mA
6541A/6551A
13 mV
6542A/6552A
5 mV
6542A
3 mA
6552A
7 mA
6542A/6552A
30 mV
6543A/6553A
10 mV
6543A
2 mA
6553A
4 mA
6543A/6553A
54 mV
6544A/6554A
15 mV
6544A
1 mA
6554A
2.5 mA
6544A/6554A
93 mV
6545A/6555A
30 mV
6545A
0.5 mA
6555A
1.25 mA
6545A/6555A
190 mV
6541A/6551A
160 mV
6541A/6551A
6542A/6552A
400 mV
6542A/6552A
6543A/6553A
700 mV
6543A/6553A
6544A/6554A
1.2 V
6544A/6554A
6545A/6555A
2.4 V
6545A/6555A
0.26% +6 mV
0.26% +15 mV
0.26% +27 mV
0.26% +45 mV
0.26% +90 mV
6541A
7.6% +18 mA
6551A
7% +75 mA
6541A
7.6% +65 mA
6551A
7% +730 mA
6542A
7.6% +9.2 mA
6552A
7% +31 mA
6542A
7.6% +32 mA
6552A
7% +400 mA
6543A
1.5%+5.5 mA
6553A
7% +16 mA
6543A
1.6% +8.1 mA
6553A
7% +120 mA
6544A
1.5%+3.2 mA
6554A
7% +8 mA
6544A
1.6% +7.1 mA
6554A
7% +80 mA
6545A
1.5%+1.4 mA
6555A
7% +5 mA
6545A
1.6% +1.8 mA
6555A
7% +75 mA
*Referenced to supply output
Note 1: For Performance Specifications, see Table 1-la.
General Information 15
Table 1-1b. Supplemental Characteristics for Series 654xA and 655xA (continued)
Parameter
Agilent Model Number and Parameter Value
Drift Temperature Stability (following a 30-minute warmup, change in output over 8 hours under constant line, load, and
ambient temperature)
Voltage:
6541A/6551A
6551A
6542A/6552A
0.02% +1 mV
6542A
0.02% +6 mA
6552A
0.02% +40 mA
0.02% +15 mA
0.02% +0.4 mV
Current:
6541A
0.02% +16 mA
6543A/6553A
0.02% +2 mV
6543A
0.02% +3 mA
6553A
0.02% +8 mA
6544A/6554A
0.02% +3 mV
6544A
0.02% +2 mA
6554A
0.02% +5 mA
6545A/6555A
0.02% +6 mV
6545A
0.02% + 1mA
6555A
0.02% + 2.5mA
Temperature Coefficients (change per °C)
Voltage:
Current:
Voltage Readback:
+Current Readback:
-Current Readback:
Overvoltage Protection:
Analog Programming (VP):
Analog Programming (IP):
Current Monitor (+IM):
Maximum Input Power:
6541A/6551A
6542A/6552A
6543A/6553A
6544A/6554A
6545A/6555A
60ppm+0.1mV
60 ppm +0.2mV
60 ppm +0.3mV
60 ppm +0.5mV
60 ppm+1.1mV
6541A
6542A
6543A
6544A
6545A
95ppm+0.82mA
95ppm+0.41mA
95ppm+0.18mA
95ppm+0.12mA
95ppm+0.04mA
6551A
6552A
6553A
6554A
6555A
90ppm+1.4mA
90ppm+0.7mA
90ppm+0.3mA
90ppm+0.2mA
90ppm+0.2mA
6541A/6551A
6542A/6552A
6543A/6553A
6544A/6554A
6545A/6555A
60ppm+0.2mV
60ppm +0.5 mV
60ppm+0.75mV
60 ppm +1.3mV
60 ppm+2.6mV
6541A
6542A
6543A
6544A
6545A
95ppm+1.2mA
95ppm+0.62mA
95ppm+0.33mA
95ppm+0.20mA
95ppm+0.08mA
6551A
6552A
6553A
6554A
6555A
90ppm+1.7mA
90ppm+0.9mA
90ppm+0.5mA
90ppm+0.3mA
90ppm+0.2mA
6541A
6542A
6543A
6544A
6545A
110ppm+1.2mA
110ppm+0.62mA
110ppm+0.33mA
110ppm+0.20mA
110ppm+0.08mA
6551A
6552A
6553A
6554A
6555A
100ppm+1.7mA
100ppm+0.9mA
100ppm+0.5mA
100ppm+0.3mA
100ppm+0.2mA
6545A/6555A
6541A/6551A
6542A/6552A
6543A/6553A
6544A/6554A
200ppm+1.6mV
200ppm+3.3mV
200ppm+5mV
200ppm+13mV
200ppm+24mV
6541A/6551A
6542A/6552A
6543A/6553A
6544A/6554A
6545A/6555A
60 ppm +0.1mV
60ppm+0.25mV
60 ppm +0.4mV
60 ppm +0.7mV
60ppm+1.25mV
6541A
6542A
6543A
6544A
6545A
90ppm+0.56mA
90ppm+0.28mA
90ppm+0.17mA
90ppm+0.1 mA
90ppm+0.04mA
6551A
6552A
6553A
6554A
6555A
85ppm+1.4mA
85ppm+0.7mA
85ppm+0.3mA
85ppm+0.2mA
85ppm+0.15mA
6541A
6542A
6543A
6544A
75ppm+0.61mA
75ppm +0.3mA
75ppm+0.06mA
75ppm+0.06mA
6545A
75ppm+0.02mA
6551A
6552A
6553A
6554A
6555A
80ppm+1.4mA
80ppm+0.7mA
80ppm+0.3mA
80ppm+0.2mA
80ppm+0.15mA
Series 654xA: 480 VA; 400 W; 60 W with no load
Series 655xA: 1380 VA; 1100 W; 120 W with no load
Maximum AC Line Current
Ratings
100 Vac nominal:
120 Vac nominal:
220 Vac nominal:
230 Vac nominal:
240 Vac nominal:
16
General Information
Series 654xA
4.4 A rms
3.8 A rms
2.2 A rms
2.1 A rms
2.0 A rms
Series 655xA
12 A rms
10 A rms
5.7 A rms
5.5 A rms
5.3 A rms
Table 1-1b. Supplemental Characteristics for Series 654xA and 655xA (continued)
Parameter
Agilent Model Number and Parameter Value
With AC input power applied and the dc output reverse biased by an external dc source,
Maximum Reverse Bias
Current:
the supply will continuously withstand without damage a current equal to its output
current rating.
Remote Sensing Capability
Voltage Drop Per Lead:
Up to 1/2 of rated output voltage.
Load Voltage:
Subtract voltage drop in load leads from specified output voltage rating.
Load Regulation:
Add 3 mV to spec (see Table l-la) for each l-volt change in the + output lead due to
load current changes.
Downprogrammer Current Capability (± 15%):
Monotonicity:
Auto-Parallel Configuration:
Analog Programming
(IP & VP)
Input Signal:*
Input Impedance:
*Signal source must be
isolated.
Current Monitor Output:
Savable States
Nonvolatile Memory
Locations:
Nonvolatile Memory Write
Cycles:
Agilent 6541
Agilent 6542
Agilent 6543
Agilent 6544
Agilent 6545
5.8 A
2.5 A
1.5 A
0.9 A
0.75 A
Agilent 6551
Agilent 6552
Agilent 6553
Agilent 6554
Agilent 6555
11.6 A
5A
3A
1.8 A
1.5 A
Output is monotonic over entire rated voltage, current, and temperature range.
Up to 3 identical models
0 to -5 V
10 kΩ, nominal
0 to -5 V represents zero to full-scale current output.
5
5 ( 0 through 4)
40,000, typical
Recommended Calibration
Interval:
1 year
Safety Compliance
Complies with:
Designed to comply with:
CSA 22.2 No.231, IEC 348, UL 1244
VDE 0411
RFI Suppression (complies
with):
FTZ 1046/84, Level B
General Information 17
Table 1-1b. Supplemental Characteristics for Series 654xA and 655xA (continued)
Parameter
Agilent Model Number and Parameter Value
Dimensions
Series 655xA
Series 654xA
425.5 mm (16.75 in)
425.5 mm (16.75 in)
Width:
132.6 mm (5.22 in)
Height:
88.1 mm (3.5 in)
Depth:
497.8 mm (19.6 in)
439 mm (17.3 in)
Weight
Net:
Shipping:
Output Characteristic Curve:
18
General Information
Series 654xA
14.2 kg (31.4 lb)
16.3 kg (36 lb)
Series 655xA
25 kg (54 lb)
28 kg (61 lb)
Table 1-1b. Supplemental Characteristics for Series 654xA and 655xA (continued)
Parameter
Agilent Model Number and Parameter Value
Output Impedance Agilent 654xA (Typical):
General Information 19
Table 1-1b. Supplemental Characteristics for Series 654xA and 655xA (continued)
Parameter
Agilent Model Number and Parameter Value
Output Impedance Curves (Typical):
20
General Information
1
Table 1-2a. Performance Specifications for Series 657xA
Agilent
Agilent
Parameter
Agilent 6572A Agilent 6573A Agilent 6574A
6571A
6575A
Specifications are warranted over the temperature range 0 to 55° C with a resistive load and the output connected for local
sensing.
Output Ratings
0-8V
0 - 20 V
0- 35 V
0 - 60 V
0 - 120 V
Voltage:
0 - 220 A
0 - 100 A
0 - 60 A
0 - 35 A
0 - 18 A
Current:
Front Panel Programming Accuracy (@ 25° C ± 5 °C)
Voltage:
Current:
0.04% +8 mV
0.l1 % +125 mA
0.04% +20 mV
0.l1 % +60 mA
0.04% +35 mV
0.l1 % +40 mA
0.04% +60 mV
0.l1 % +25 mA
Ripple & Noise (from 20 Hz to 20 MHz with outputs ungrounded, or with either output terminal grounded)
1.25 mV
Constant Voltage(rms):
650 µV
750 µV
800 µV
7 mV
9 mV
9 mV
11 mV
Constant Voltage (p-p):
200 mA
100 mA
40 mA
25 mA
Constant Current (rms):
Readback Accuracy (with respect to actual output @ 25° C ± 5 °C)
0.05% +12 mV
0.05% +30 mV
0.05% +50 mV
Voltage:
0.1% +150 mA
0.1% +100 mA
0.1% +60 mA
Current
Load Regulation (change in output voltage or current for any load change within ratings)
0.002%+1.2mV
0.002%+300µV
0.002%+650µV
Voltage:
0.005%+10 mA
0.005%+7 mA
0.005%+4 mA
Current:
1.9 mV
16 mV
12 mA
0.05% +90 mV
0.1% +35 mA
0.05% +180 mV
0.1% +18 mA
0.002%+2mV
0.005%+2 mA
0.002%+4mV
0.005%+1 mA
0.002%+2mV
0.005%+2 mA
0.002%+4mV
0.005%+1 mA
Line Regulation (change in output voltage or current for any line change within ratings
0.002%+1.2mV
0.002%+300µV
0.002%+650µV
Voltage:
0.005%+10 mA
0.005%+7 mA
0.005%+4 mA
Current:
Transient Response Time
0.04% +120 mV
0.l1 % +12 mA
< 900 µS for the output voltage to recover to within 100 mV following any step
change in load current from 100% to 50%, or 50% to 100% of the rated current.
AC Input Ratings (selectable via internal switching - see Appendix B)
Nominal line voltage
174-220 Vac
200 Vac:
(Below 185 Vac, derate
output voltage linearly to:)
230 Vac:
Frequency range:
Output Terminal Isolation
7.8 V
18.0 V
31.5 V
56.5 V
108 V
191-250 Vac
47-63 Hz
±240 Vdc (maximum, from output signal ground)
Note 1: For Supplemental Characteristics, see Table 1-2b.
General Information 21
Table 1-2b. Supplemental Characteristics for Series 665xA (Note 1)
Agilent
Agilent
Parameter
Agilent 6572A
Agilent 6574A
6571A
6573A
Output Programming Range (maximum programmable values)
8.190 V
20.475 V
35.831 V
61.425 V
Voltage:
10.0 V
24.0 V
42.0 V
72.0 V
Overvoltage Protection (OVP):
225.23 A
102.37 A
61.43 A
35.83 A
Current:
Average Resolution
2 mV
5 mV
10 mV
15 mV
Voltage:
55 mA
25 mA
15 mA
8.75 mA
Current:
15 mV
35 mV
65 mV
100 mV
OV Protection:
Agilent 6575A
122.85 V
144.0 V
18.43 A
30 mV
4.5 mA
215 mV
Accuracy (at calibration temperature ±5° C)*
200 mV
500 mV
900 mV
1.15 V
3.0 V
Overvoltage Protection :
Analog Programming (VP):
±0.3%
Analog Programming (IP):
±7%
Current Monitor (+IM):
±7%
*Factory calibration temp =25°C
Drift Temperature Stability (following a 30-minute warmup, change in output over 8 hours under constant line, load, and
ambient temperature)
0.02%+0.24mV
0.02% +0.6 mV
0.02% +1 mV
0.02% +1.8 mV
0.02% +3.6 mV
Voltage:
0.02% +69mA
0.02% +35mA
0.02% +20mA
0.02% +10 mA
0.02% +6mA
Current:
Temperature Coefficients (change / °C and 30-minute warmup)
50ppm+0.04mV 50ppm +0.2 mV 50ppm+0.7mV 50ppm +1.2 mV 50 ppm+2.4 mV
Voltage:
Current:
75 ppm +25mA
75 ppm +12 mA
75 ppm +7 mA
75 ppm +4 mA
75 ppm +2 mA
Voltage Readback:
60 ppm +0.1mV
60 ppm +0.3mV
60 ppm +1 mV
60 ppm +1.2mV
60 ppm +3 mV
±Current Readback:
85 ppm +30 mA
85 ppm +15 mA
85 ppm +9 mA
85 ppm +5 mA
85 ppm +2.5mA
Overvoltage Protection:
200ppm+1.8mV
200 ppm +5 mV
200 ppm+8mV
200 ppm+13mV
200 ppm+25mV
Analog Programming (VP):
60 ppm +0.1mV
60 ppm +0.3mV
60ppm+0.5mV
60 ppm +0.7mV
60 ppm +1.5mV
Analog Programming (±IP):
275ppm+26mA
275 ppm+14mA
275 ppm+9mA
275 ppm +5 mA
275 ppm +3 mA
50 ppm +3mA
50 ppm +2mA
50 ppm+1mA
50ppm+0.6mA
50ppm+0.3mA
Current Monitor (+IM):
3800 VA; 2600 W, 100 W with no load
Maximum Input Power
Maximum AC Line Current Ratings
19 A rms
200 Vac nominal:
230 Vac nominal:
19 A rms
Maximum Reverse Bias Current: With AC input power applied and the dc output reverse biased by an external dc
source, the supply will continuously withstand without damage a current equal to its
output current rating.
Remote Sensing Capability
Voltage Drop Per Lead:
Up to 1/2 of rated output voltage.
Load Voltage:
Subtract voltage drop in load leads from specified output voltage rating.
Load Regulation:
Degradation due to load lead drop in -output: None
Degradation due to load lead drop in + output: ∆mV (regulation) = 2Vdrop (Vrating)/(Vrating +10V)
Note 1: For Performance Specifications, see Table l-1b.
22
General Information
Table 1-2b. Supplemental Characteristics for Series 665xA (continued)
Agilent
Parameter
Agilent 6572A Agilent 6573A Agilent 6574A Agilent 6575A
6571A
Output is monotonic over entire rated voltage, current, and temperature range.
Monotonicity:
Up to 5 identical models.
Auto-Parallel Configuration:
Analog Programming (IP & VP)
Input Signal*
0 to -4.72 V
0 to -4.24 V
0 to -4.25 V
0 to -4.24 V
0 to -3.97 V
VP Input:**
+IP/-IP Differential
0 to +7.97V
0 to +6.81 V
0 to +6.81 V
0 to +7.01 V
0 to +6.34 V
Input:
Input Impedance
VP Input:
60 kΩ,
IP Input:
52 kΩ
*Signal source must be isolated. **Referenced to output signal common.
Current Monitor (IM)
-0.25 to +9.05V
-0.25 to +7.7 V
-0.25 to +7.7 V
-0.25 to +7.93V
-0.25 to +7.15V
Output Signal:*
Output Impedance:
490 Ω
*Corresponds to 0% to 100% output current.
5
Savable States
Nonvolatile Memory
Locations:
5 ( 0 through 4)
Nonvolatile Memory Write
Cycles:
40,000, typical
Recommended Calibration
Interval:
1 year
Safety Compliance
CSA 22.2 No.231 & IEC 348
Complies with:
Designed to comply with:
UL 1244 & VDE 0411
RFI Suppression (complies
FTZ 1046/84, Level B
with):
Dimensions
425.5 mm (16.75 in)
Width:
Height:
132.6 mm (5.22 in)
Depth (w/safety cover):
640 mm (25.2 in)
Weight
27.7 kg (61 lb)
Net:
Shipping:
31.4 kg (69 lb)
Output Characteristic Curve:
General Information 23
Table 1-2b. Supplemental Characteristics for Series 665xA (continued)
Agilent
Parameter
Agilent 6572A Agilent 6573A Agilent 6574A
6571A
Output Impedance Curves Agilent 657xA (Typical):
24
General Information
Agilent 6575A
Table 1-3. Replaceable Parts List
Description
(Unless otherwise specified, parts apply to all models.)
Collar, rotary output control
Foot, cabinet
Fuse, power
Series 654xA, 100 Vac line voltage, 6 AM
Series 654xA, 120 Vac line voltage, 5 AM
Series 654xA, 220/230/240 Vac line voltage, 3 AM
Series 655xA, 100 Vac line voltage, 15 AM
Series 655xA, 120 Vac line voltage, 12 AM
Series 655xA, 220/230/240 Vac line voltage, 7 AM
Series 657xA, 200 Vac line voltage, 25 AM*
Series 657xA, 230 Vac line voltage, 25 AM*
*This is an internal fuse not replaceable by the operator.
Knob, rotary output control
Lockwasher, output bus bar, 1/4 spring (Series 657xA)
Manual, service (Series 654xA and 655xA)
Manual, service (Series 657xA and 667xA)
Nut, output bus bar, hex 1/4-20xl/2 (Series 657xA)
Nut, power ground, hex w/lw 3/8x32
Power cord assembly (Series 657xA)
Resistor, calibration
Safety cover, ac input, w/strain relief connector & rubber boot (Series 657xA)
Safety cover, dc output (Series 654xA/655xA)
Safety cover, dc output (Series 657xA)
Screw, bus bar (Series 655xA)
Screw, carrying strap & safety cover, M5x0.8xl0 mm
Screw, dc output safety cover (Series 654xA,655xA)
Screw, output bus bar, 1/4-20xl/2 (Series 657xA)
Screw, output sense terminal, M3x0.5x8 mm
Terminal, crimp, ac power cord, L or N terminal (Series 657xA)
Terminal, crimp, ac power cord, Gnd terminal (Series 657xA)
Agilent Part No.
5040-1700
5041-8801
2110-0056
2110-0010
2110-0003
2110-0054
2110-0249
2110-0614
2110-0849
2110-0849
0370-1091
3050-1690
5959-3376
5961-2583
2950-0084
0590-0305
(See “Options”)
(See Appendix A)
5040-1676
0360-2191
5040-1674
0515-1085
0515-1132
0515-1085
2940-0103
0515-0104
0362-0681
0362-0207
General Information 25
2
Installation
Inspection
Damage
When you receive your power supply, inspect it for any obvious damage that may have occurred during shipment. If there is
damage, notify the shipping carrier and the nearest Agilent Sales and Support office immediately. Warranty information is
printed in the front of this guide.
Save the shipping carton and packing materials in case the power supply must be returned to Agilent Technologies. If you
return it for service, attach a tag identifying the model number and the owner. Also include a brief description of the
problem.
Items Supplied
In addition to this manual, check that the following items are included with your power supply (see Table 1-4 for part
numbers):
Power cord
Your power supply was shipped with a power cord for the type of outlet specified for your location. If the appropriate cord
was not included, contact your nearest Agilent Sales and Support office (see end of this manual) to obtain the correct cord.
Your power supply cannot use a standard power cord. The power cords supplied by Agilent
Technologies have heavier gauge wire.
Series 657xA Only
These power supplies also include output hardware (screws with nuts and lockwashers) for securing your load wires to the
output bus bars (see Table 1-4).
Manual Change Page
If applicable, change sheets may be included with this manual. If there are change sheets, make the indicated corrections to
this manual.
Location and Cooling
Bench Operation
The “Supplemental Characteristics” in Chapter 1 give the dimensions of your power supply. The cabinet has plastic feet that
are shaped to ensure self-alignment when stacked with other Agilent System II cabinets. The feet may be removed for rack
mounting. Your power supply must be installed in a location that allows sufficient space at the sides and rear of the cabinet
for adequate air circulation. Minimum clearances are 1 inch (25 mm) along the sides. Do not block the fan exhaust at the
rear of the supply.
Rack Mounting
The power supply can be mounted in a standard 19-inch rack panel or cabinet. Rack mounting kits are available as Option
908 or 909 (with handles). Installation instructions are included with each rack mounting kit. Instrument support rails are
required for non-stationary installations. These are normally ordered with the cabinet and are not included with the rack
mounting kits.
Installation 27
Temperature Performance
A variable-speed fan cools the supply by drawing air through the sides and exhausting it out the back. Using Agilent rack
mount or slides will not impede the flow of air. The temperature performance is as follows:
Series 654xA/655xA
Operates without loss of performance within the temperature range of 0 ºC to 40 ºC and with
derated output from 40 °C to 55 °C.
Series 657xA
Operates without loss of performance within the temperature range of 0 °C to 55 °C.
Input Power Source
Refer to the applicable paragraphs below for information on the input power source. Do not apply power to the power
supply until directed to do so in Chapter 3.
Check the line
label on the rear of your supply and verify that the voltage shown there
corresponds to the nominal line voltage of your power source. If it does not, see Appendix B for
instructions on changing the power supply's line voltage configuration.
Series 654xA and 655xA
You can operate your supply from a nominal 100 V, 120 V, 220 V, 230 V, or 240 V single -phase ac power source as
indicated on the rear panel line Rating label. See "AC Input Ratings" in Table 1-la for the voltage and frequency range for
each type of power source. "Maximum AC Line Current Ratings" in Table 1-2a shows the required current load. The line
fuse is located in a fuseholder on the rear panel (see Figure 2-1). The Line Fuse label on the rear panel shows the fuse value
used in the power supply and Table 1-4 identifies the replacement fuse.
Figure 2-1. Series 654xA and 655xA Power Connection
Series 657xA
Input Source and Line Fuse
You can operate your supply from a nominal 200 or 230 volt single-phase ac power source as indicated on the rear panel
Line Rating label. See "AC Input Ratings" in Table 1-lb for the voltage and frequency range for each nominal power
source. "Maximum AC Line Current Ratings" in Table 1-2b shows the required current load.
28
Installation
Note
The power source must be a dedicated line with no other devices drawing current from it.
The line fuse is located inside the power supply. Table 1-4 identifies the replacement fuse. See "In Case of Trouble" in
Chapter 3 for instructions on fuse replacement.
Installing the Power Cord
The power cord supplied with power supply may or may not include a power plug (see "Options" in Chapter 1) at one end
of the cord. Terminating connections and a ground lug are attached to the other end of the cord.
Installation of the power cord must be done by a qualified electrician and in accordance with local
electrical codes.
See Figure 2-2 and proceed as follows:
1.
If they are not already in place, position the strain relief connector (11), power safety cover (5), rubber boot (9), and
connector nut (8) on the power cord (7).
2.
Secure the ground connection wire (2) to the chassis earth ground stud.
3.
Connect the neutral connection wire (l) to the N power input terminal.
4.
Connect the line connection wire (3) to the L power input terminal. This line is fused inside the power supply
5.
Position the safety cover (5) over the power input terminals and tighten the cover and strain relief connector screws (6
and 10).
Figure 2-2. Series 657xA Power Cord Installation
Installation 29
3
Turn-On Checkout
Note
This chapter provides a preliminary introduction to the power supply front panel. See Chapter 5 for more
details.
Introduction
Successful tests in this chapter provide a high degree of confidence that the power supply is operating properly. For
complete performance and/or verification tests, refer to the service manual (see Table 1-4 in Chapter 1).
Do not connect the power cord to the power source until told to do so .
Preliminary Checkout
Series 654xA and 655xA Power Supplies
If required, see Figure 2-1 in Chapter 2 and Figure 4-1 in Chapter 4 for parts locations.
I. Make certain that the front panel switch is off.
II. Examine the Line And Fuse Rating label (3, Figure 2-1).
A. Verify that the line voltage rating agrees with your power source. If it does not, see Appendix B.
B. Use a screwdriver to remove the line fuse from the fuseholder (1, Figure 2-1). Verify that the fuse is as specified on
the label. Replace the fuse.
III. Check that the SENSE switch (4, Figure 4-1) is set to Local.
IV. Make sure that there is no load connected to the output (+) and (-) terminals (2, Figure 4-2).
Series 657xA Power Supplies
I.
Examine the Line Voltage label (4, Figure 2-2) and verify that the line voltage rating agrees with your power source. If
it does not, see Appendix B.
II. Remove the output safety cover (1, Figure 4-2).
III. Examine the output sense terminals (4 and 5, Figure 4-2). They should be wired for local sensing as follows:
A. The +LS sense terminal wired to the +S terminal of the analog connector (2, Figure 4-2) .
B. The -LS sense terminal wired to the -S terminal of the analog connector.
C. If the power supply is not wired for local sensing, make the above connections, using small-capacity wire (#22 is
sufficient).
IV. Make certain there is no load connected to the bus bars.
Turn-On Checkout 31
POWER-ON Checkout
1.
2.
3.
Connect the power cord to the power source.
Turn the front panel power switch to ON (1).
Check that the power supply fan is on by placing your hand near the rear grill to feel the air flow. You may also be able
to hear the fan operating.
The power supply undergoes a self-test when you turn it on. If the test is normal, the following sequence appears on the
LCD:
1.
2.
3.
A brief star-burst pattern
PWR 0N INIT for a few seconds (Series 657xA supplies only).
The display goes into the meter mode with the Dis annunciator on and all others off. “Meter mode” means that the
VOLTS digits indicate the output voltage and the AMPS digits indicate the output current. These values will be at or
near zero.
Note
4.
If the power supply detects an error during self-test, the display will show an error message. Go to “In
Case of Trouble” at the end of this chapter.
Press
once. The Dis annunciator will go off and the CV annunciator will go on.
Output Checkout
Shifted Keys
Some of the front panel keys perform two functions, one labeled in black and the other in blue. You access the blue function
key, which is not labeled. When the Shift annunciator is on, you will know you have
by first pressing the blue
access to the key's shifted (blue) function.
Backspace Key
key is an erase key. If you make a mistake entering a number and have not yet entered it (have not pressed
), you can delete the number by pressing
. You may delete as many numbers as you wish by repeatedly
pressing this key.
The
Note
The voltage and current values used in these tests are for a typical Agilent 655xA Series supply (the
Agilent 6552A). Table 1-la and Table 1-lb in Chapter 1 lists the ranges for other supplies. If needed, refer
to those tables for the voltage and current ratings of your supply.
Setting The Output Voltage
Perform the steps in Table 3-1 to check the basic voltage functions with no load connected to the power supply. The VOLTS
display will show various readings. Ignore the AMPS display.
Setting The Output Current
You must have a load on the power supply to generate a current output. For this purpose, you will connect a shorting wire
across the output terminals of the supply.
32
Turn-On Checkout
Some power supplies have a high output current capacity. To prevent overheating or possible melting of
the shorting wire, make sure it is of sufficient size to carry the supply’s maximum output current (see
Table 4-2 in Chapter 4 for the appropriate wire size).
Perform the steps in Table 3-2 to check the basic current functions with a short across the power supply output. The AMPS
display will show various readings. Ignore the VOLTS display.
Table 3-1. Checking the Voltage Functions (Output Terminals Open)
If the Dis annunciator is on, turn it off by pressing
Press
VOLT 0.000
Displays default output voltage. CV annunciator is on. If CC
annunciator remains on, increase the CC current setting by
pressing
Press
V0LT 20
*Set voltage to supply’s rated output.
Press
20.000
Meter mode displays output voltage.
Press
several times
**Voltage drops about 5 millivolts each time you press the key.
Press
times
the same number of
**Voltage increases about 5 millivolts each time you press the
key.
Rotate the Voltage control first
counterclockwise and then clockwise
Control operates similarly to the
and
keys.
Turning the controls more quickly causes a more rapid change
in voltage.
Press
0V 22.000
***Shows the default OVP trip voltage.
Press
0V 15
Program OV trip voltage to 15.
Press
You have entered a trip voltage that is less than the output
voltage. The output drops to near zero. The CV annunciator
goes off and the Prot annunciator comes on.
Press
0V
Press
Meter mode
Press
0V 21
Press
Press
Indicates the overvoltage Protection circuit has tripped.
Raise the OV trip voltage up above the programmed output
voltage.
Enter the new trip voltage.
****
20.000
You have cleared the OV protection fault. The Prot
annunciator goes off, the CV annunciator comes on, and the full
rated output is restored.
Turn-On Checkout 33
Table 3-1. Checking the Voltage Functions (continued)
*Maximum voltage values are for Agilent 6552A. See “Output Ratings” in “Performance Specifications” of Chapter 1
for your specific model.
**Voltage increments are for Agilent 6552A. See “Average Resolution” in “Supplemental Characteristics” of Chapter 1
for your specific model.
***OV voltage is for Agilent 6552A. See “Output Programming Range” in “Supplemental Characteristics” of Chapter 1
for your specific model.
****
key is the unlabeled blue key.
Table 3-2. Checking the Current Functions (Output Terminals Shorted)
Turn off the power supply and connect a wire across the output (+) and (-) terminals. Use a wire of sufficient size to
carry the maximum current of the supply (see "Performance Specifications" in Chapter 1).
Turn on the supply
Meter mode
Essentially zero outputs with Dis annunciator on.
Press
VOLT 1.500
Set a minimum operating voltage to cause current to low.
Press
Dis annunciator goes off, CC annunciator comes on, and
AMPS display shows some current. If there is no current and
CV annunciator remains on, increase the operating voltage
setting.
Press
several times
*Current increases about 7 milliamperes each time you press
the key.
Press
times
the same number of
*Current decreases about 7 milliamperes each time you press
the key.
Rotate the Current control first
clockwise and then counterclockwise.
Control operates similarly to the
and
keys. Turning the controls more quickly causes a more rapid
change in current.
Press
You have enabled the overcurrent protection circuit, which
tripped because of the output short. The CC annunciator goes
off and the OCP and Prot annunciators come on. The output
current is near zero.
Press
OC
Press
Meter mode
Indicates the overcurrent protection circuit has tripped. (see
“Supplemental Characteristics” in Chapter 1).
Press
Dis annunciator comes on.
Press
You have disabled the overcurrent protection circuit. The
OCP annunciator goes off.
Press
34
*
Turn-On Checkout
You have cleared the OC protection circuit. The Prot
annunciator goes off.
Press
Table 3-2. Checking the Current Functions (continued)
Dis annunciator goes off and the CC annunciator comes on.
AMPS shows some current.
Press
Press
25.000
**AMPS increases to maximum output.
Dis annunciator comes on and AMPS reading drops to near
zero.
Turn off the power supply and remove the short from the output terminals.
* Current increments are for Agilent 6552A. See "Average Resolution” in "Supplemental Characteristics of Chapter 1
for your specific model.
** Maximum current value is for Agilent 6552A. See “Output Ratings” in “Performance Specifications” of Chapter 1 for
your specific model.
****
key is the unlabeled blue key.
Save/Recall Checkout
The following steps check the power supply save and recall function keys.
n
n
n
n
Make certain that the Dis annunciator is off. Then set the voltage output to 5 volts by pressing
.
.
Save this value to location 1 by pressing
. This recalls the power supply values stored in location 0,
Remove the output voltage by pressing
which are the factory reset values (see Chapter 5 for more information).
and notice that the output voltage returns to 5.
Press
In Case Of Trouble
Line Fuse
If the power supply appears "dead" with a blank display and the fan not running, first check your power source to be certain
line voltage is being supplied to the power supply. If the power source is normal, the power supply line fuse may be
defective. If this is the case, replace the fuse only once. If it fails again, investigate the reason for the failure. Proceed as
follows:
Series 654xA and 655xA Supplies
The line fuse is located on the rear panel (1, Figure 2-1). Proceed as follows:
1.
2.
3.
Turn off the front panel power switch.
Using a screwdriver, remove the fuse from the fuseholder. Replace it with one of the same type (see Table 1-4 in
Chapter 1). Do not use a "slow-blow" type fuse.
Turn on the power supply and check the operation.
Turn-On Checkout 35
Series 657xA Supplies
Hazardous voltage can remain inside the power supply even after it has been turned off. Fuse
replacement should be done only by qualified electronics personnel.
The line fuse is located inside the power supply. To change it, proceed as follows:
I. Turn off the front panel power switch and unplug the line cord from the power source.
II. Remove the power supply dustcover as follows:
A. Remove the four screws securing the carrying straps and dustcover.
B. Spread the bottom rear of the dustcover and pull it back to disengage it from the front panel.
C. Slide the dustcover back far enough to expose the line fuse (1, Figure 3-1).
III. Observe the input rail LED under the RFI shield (4, Figure B-3 in Appendix B). If the LED is on, there is still
hazardous voltage inside the supply. Wait until the LED goes out (this may take several minutes) before proceeding.
IV. Connect a dc voltmeter across test points TP1 and TP2 (see Figure B-3). It may be necessary to remove the RFI shield
in order to reach these test points. (The shield is secured by four screws on each side.) When the voltmeter indicates 60
volts or less, it is safe to work inside the power supply.
V. Replace the fuse with one of the same type (see Table 1-4 in Chapter 1). Do not use a "slow-blow" type fuse.
VI. If you removed it in step b, be sure to replace the RFI shield.
VII. Replace the dustcover.
VIII.
Connect the line cord to the power source.
IX. Turn on the front panel power switch and check the operation.
Figure 3-1. Series 657xA Line Fuse
Error Messages
Power supply failure may occur during power-on selftest or during operation. In either case the display may show an error
message that indicates the reason for the failure.
36
Turn-On Checkout
Selftest Errors
When a selftest error occurs, it prevents all front panel operation. The display may show either a power-on error message or
a checksum error message.
Power-on Error Messages. Power-on messages appear as:
En- - - - - Where “n” is a number listed in Table 3-3. If this occurs, turn the power off and then back on to see if the error persists. It is
possible to recover from the EE CHKSUM error (see "Checksum Errors"). If any other message persists, the power supply
requires service.
Error No
Table 3-3. Power-on Selftest Errors
Display
Failed Test
E1
FP RAM
Front Panel RAM
E2
FP ROM
Front Panel ROM checksum
E3
EE CHKSUM
E4
E5
E6
E7
E8
E9
E10
E11
E12
SEC RAM
SEC R0M
SEC 5V
TEMP
DACS
EEPROM
(Not used)
(Not used)
(Not used)
(Not used)
Secondary RAM
Secondary ROM checksum
Secondary 5 V ADC reading
Secondary ambient thermistor reading
Secondary VDAC/IDAC readback
Checksum Errors.
If the display shows EE CHKSUM, the power supply has detected an EEPROM checksum error. A checksum error can occur
due to the following conditions:
n
n
Excessive number of write cycles to an EEPROM (see "Supplemental Characteristics"). This condition, which would
appear only after extended use, is not recoverable and requires service.
Loss of ac input power during a checksum calculation. This condition, which is very unlikely, is recoverable.
You may be able to recover from a checksum error by writing to the EEPROM while the power supply is in the calibration
mode. To do this, proceed as follows:
1.
2.
3.
Enable the calibration mode by pressing
PASWD will appear on the display.
Press the number keys corresponding to the password, followed by
Note
.
. The Cal annunciator will go on.
On new equipment, the calibration password corresponds to the four- digit model number (such as
). See Appendix A for more information about the calibration password.
Turn-On Checkout 37
4.
5.
Save any operating state (for example, press
Turn the power off and then back on.
A normal display free of error messages should appear. If not, the power supply requires service.
Runtime Error Messages
Under unusual operating conditions, the V0LT or AMPS display may show +OL or -OL. This indicates that the output
voltage or current is beyond the range of the meter readback circuit.
Table 3-4 shows other error messages that may appear at runtime.
Display
EE WRITE ERR
SBUB FULL
SERIAL DOWN
STK OVERFLOW
UART FRAMING
UART OVERRUN
UART PARITY
38
Turn-On Checkout
Table 3-4. Runtime Errors
Meaning
EEPROM status time-out
Message too long for buffer
Failed communication with front panel
Front panel stack overflow
UART byte framing error
Overfilled UART receive buffer
UART byte parity error
4
User Connections and Considerations
Rear Panel Connections
Shock Hazard Disconnect ac power before making rear panel connections.
Application connections are made to the output terminals and analog connector. The connections are the same for Series
654xA and 655xA supplies and similar for the Series 657xA supplies. Unless otherwise specified, instructions in this
chapter apply to all models.
Output Connectors
The + and - load connections are made at the rear panel. Depending on the model (see Figure 4-1 or Figure 4-2), either
terminals or screw-down bus bars (+ and -) connect the load to the power supply. The general procedure is as follows:
1. Remove the output safety cover.
2. Connect the load wires.
3. Replace the output safety cover.
For more specific information, refer to the following applicable paragraph.
Series 654xA and 655xA Supplies
• On Series 654xA:
• strip the end of each load wire and secure it to the appropriate terminal, using the screw provided on the terminal.
•
On Series 655xA:
• strip the end of each load wire and fasten a suitable terminal lug to the end.
• using the screws provided on the output bus bars, attach the wire terminal lugs to the bus bars.
Series 657xA Supplies
• strip the end of each load wire and fasten a suitable terminal lug to the end.
• make a suitable opening in the output safety cover by removing one or more cover knockouts (see Figure 4-2).
Do not leave uncovered holes in the safety cover. If too many knockouts have been removed, install a
new cover (see Table 1-3).
•
•
feed the wires through the safety cover.
using the screws provided on the output bus bars, attach the wire terminal lugs to the bus bars.
Analog Connector
The rear panel has a 7-pin analog connector with quick-disconnect plug (see Figure 4-3) for making the following optional
connections:
• remote sense leads
• an external current monitor
• an external programming voltage source
• connecting two or more power supplies in auto-parallel
User Connections and Considerations 39
Figure 4-1. Series 654xA and 655xA Rear Panel Connections
Figure 4-2. Series 657xA Rear Panel Connections
The connector accepts wire sizes from AWG 22 to AWG 12. The purpose of each analog pin is described in Table 4 -1.
Note In addition to specific wiring instructions given in this chapter, it is good engineering practice to
twist and shield all signal wires to and from the analog connector.
40
User Connections and Considerations
Table 4-1. Analog Connector Functions
Function
Series 654xA and 655xA
Current programming Input. Allows an external voltage source to program CC (constant current) mode.
CC is programmed with a 0 to -5 V signal that produces proportional output current from zero to full scale.
The IP input is also used for auto-parallel operation as described later in this chapter.
Series 657xA
±IP
Differential Current Programming Input. Allows an external voltage source to program CC (constant
current) mode. ±IP accepts a signal (see Analog Programming in Table 1-2b) that produces a proportional
output current from zero to full scale. +IP is positive with respect to -IP. -IP may be floated up to ±19 V from
the Common P (↓P) terminal, which is approximately at the same potential as the + output. The ±IP input is
also used for auto-parallel operation as described later in this chapter.
VP
Voltage Programming Input. Allows an external voltage source to program CV (constant voltage) mode.
CV is programmed with a signal (see Analog Programming (IP & VP) in “Supplemental Characteristics”)
that produces a proportional output voltage from zero to full scale.
+IM
Series 654xA and 655xA
Current Monitor Output. Monitors the output current with respect to Common P (↓P). A 0 to -5 V signal
at this output indicates a zero-to-full scale current. +IM is also used when connecting supplies in autoparallel
for increased current output (see “Auto-Parallel Operation”).
-IM
Series 654xA and 655xA
Current Monitor Input. Connects to Common P (↓P) when connecting supplies in autoparallel for
increased current output (see “Auto-Parallel Operation”).
IM
Series 657xA
Current Monitor Output. Monitors the output current with respect to Common P (↓P). A signal (see
Current Monitor (IM) in Table 1-2b) at this output indicates a zero-to-full scale current. +IM is also used
when connecting supplies in autoparallel for increased current output (see “Auto-Parallel Operation”).
Common P Series 654xA and 655xA
Common Return. Provides the common connection for the IP and VP programming inputs and the +IM
(↓P)
current monitor output.
Common P Series 657xA
Common Return. Provides the common connection for the VP programming input and the IM current
(↓P)
monitor output.
Series 654xA and 655xA
±S
Remote Sense Inputs. Connects the load sense input leads to the power supply when the rear panel Remote
Sense switch is in the Remote position (see “Remote Sensing” ).
Series 657xA
±S
Sense Inputs. Connects the power supply sense input to either the +LS and -LS terminals for local sensing
(see “Local Voltage Sensing”) or to the load for remote sensing (see “Remote Voltage Sensing”).
After you have finished making the analog connections, insert the plug back into the analog connector and replace the
output safety cover.
Pin
IP
Wire Size Selection
The minimum wire size required to prevent wire overheating still may not be large enough to maintain a small enough loadlead voltage drop for good electrical performance. See “Remote Sensing” and “OVP Considerations” for more information
on this topic. Table 4-2 gives the wire resistance for various stranded sizes to help you determine load-lead drop.
Fire Hazard To satisfy safety requirements, load wires must be heavy enough not to overheat when
carrying the maximum short-circuit current of the power supply.
User Connections and Considerations 41
.
Figure 4-3. Analog Connector
Table 4-2. Stranded Copper Wire Ampere Capacity and Resistance
Ampacity Resistance
AWG
Area
Ampacity
AWG
Area
2
2
No.
(mm )
No.
(mm )
(Ω/m)
18
0.82
15.4
0.0210
8
8.37
75
16
1.31
19.4
0.0131
6
13.3
100
14
2.08
31.2
0.0082
4
21.1
135
12
3.31
40.0
0.0052
2
33.2
180
10
5.26
55.0
0.0033
1/0
53.0
245
Note:
1. AWG wire rating derived from MIL-W-5088B.
2. Ampacity of aluminum wire is approximately 84% that of copper wire.
3. With bundled wires, use the following percentages of the rated ampacity:
2 conductors 94%
4 conductors 83%
3 conductors 89%
5 conductors 76%
4. Maximum temperatures. ambient = 50° C; conductor = l05° C.
Resistance
(Ω/m)
0.0020
0.0013
0.0008
0.0005
0.0003
Output Isolation
The output of the power supply is isolated from earth ground. Either output terminal may be grounded, or an external
voltage source may be connected between either output and ground. However, both output terminals must be kept within
±240 Vdc of ground. An earth ground terminal is provided on the rear panel for convenience, such as grounding wire
shields.
The earth ground terminal on the rear panel is a low-noise signal ground for convenience only. It Is not
designed to function as a safety ground.
42
User Connections and Considerations
Load Considerations
Capacitive Loads
In most cases, the power supply will continue to be stable with additional external load capacitors (see the following table
for Series 654xA/665xA recommendations). However, large load capacitors may cause ringing in the supply’s transient
response. It is possible that certain combinations of load capacitance, equivalent series resistance, and load lead inductance
will result in instability. If you need help in solving a stability problem, contact an Agilent service engineer through your
local Sales and Support office (see end of this manual).
Series 654xA/655xA Power Supplies, Maximum External Capacitance
6541A
40,000µF
6542A
20,000µF
6543A
12,000µF
6544A
7,000µF
6545A
3,000µF
6551A
100,000µF
6552A
50,000µF
6553A
30,000µF
6554A
18,000µF
6555A
8,000µF
If the power supply output is rapidly programmed into capacitive loads, the supply may momentarily cross into CC mode.
This extends the CV programming time and limits the maximum slew rate to the programmed current divided by the total
internal (see “Inductive Loads”) and external capacitance. These momentary crossovers into CC mode will not damage the
supply.
Inductive Loads
Inductive loads provide no loop stability problems in CV mode. However, in CC mode inductive loads will form a parallel
resonance network with the power supply's output capacitor. Generally, this will not affect the stability of the supply, but it
may cause ringing of the current in the load. Ringing will not occur if the Q (quality factor) of the parallel resonant network
is ≤ 0.5. Use the following formula to determine the Q of your output.
Q=
1
R int + Rext
L
C
where C = model-dependent internal capacitance (see below); L = inductance of the load; Rext = equivalent series resistance
of the load; Rint = model-dependent internal resistance (see below):
C=
Rint =
C=
Rint =
6541A
4,200µF
7 mΩ
6542A
550µF
30 mΩ
6543A
180µF
50 mΩ
6544A
68µF
125 mΩ
6555A
50µF
250 mΩ
6571A
44,000µF
1.8 mΩ
6572A
44,000µF
2.2 mΩ
6573A
12,000µF
4 mΩ
6545A
33µF
300 mΩ
6574A
7,000µF
14 mΩ
6551A
10,000µF
4 mΩ
6552A
1,100µF
20 mΩ
6553A
440µF
30 mΩ
6554A
120µF
80 mΩ
6575A
2,100µF
30 mΩ
Note for Series 657xA Supplies: If Q >0.5, inductive loads will ring with the output capacitance and be damped according
to the following equation


−t
e
2L

 

R 


 s in ω t



 1 
1− 

 2Q 
2
User Connections and Considerations 43
Multiple Loads
When connecting multiple loads to the power supply using local sensing, use separate wires to connect each load to the
output terminals (see Figure 4-4). This minimizes mutual coupling effects and takes full advantage of the power supply’s
low output impedance. Each pair of wires should be as short as possible and twisted or bundled to reduce lead inductance
and noise pickup.
If cabling considerations require the use of distribution terminals that are remotely located from the supply, connect the
output terminals to the distribution terminals by a pair of twisted or bundled wires. Use separate wires for connecting each
load to the distribution terminals. In these circumstances, remote voltage sensing is recommended (see “Remote Voltage
Sensing”). Sense either at the remote distribution terminals or, if one load is more critical than the others, directly at the
critical load (see dashed lines in Figure 4-l). Note that the power supply’s voltage readback occurs at the sense terminals.
Figure 4-4. Multiple Load Connections (Remote Sensing Optional)
Local Voltage Sensing
Your power supply was shipped set up for local sensing. This means that the supply will sense and regulate its output at the
output terminals, not at the load. Since local sensing does not compensate for voltage drops across screw terminals, bus
bars, or load leads, local sensing should only be used in applications that require low output current or where load regulation
is not critical.
Series 654xA and 655xA Supplies
Local sensing is obtained by placing the SENSE switch (see Figure 4-1) in the Local position. The power supply is shipped
with the switch in this position.
Series 657xA Supplies
Local sensing is obtained by connecting the +LS sense terminal to the +S analog connector pin and the pin and the -LS
sense terminal to the -S analog connector pin. The power supply is shipped with these connections made.
Note
44
If the sense terminals are left unconnected, the voltage at the bus bars will increase approximately 3 to 5
% over the programmed value. Since it is measured at the sense terminals, the voltage readback will not
reflect this increased output.
User Connections and Considerations
Remote Voltage Sensing
The dashed lines in Figure 4-4 illustrate a typical power supply setup using remote voltage sensing. In this case, the remote
sense terminals of the power supply are connected directly to the load rather than to the output terminals. This allows the
supply to automatically compensate for the voltage drop in the load leads as well as to accurately read back the voltage
directly across the load.
Setting Up Remote Sense Operation
Series 654xA and 655xA Supplies
Remote sensing is obtained by placing the SENSE switch (see Figure l-1) in the Remote position. The power supply is
shipped with the switch in the Local position.
Series 667xA Supplies
Remote sensing is obtained by removing the jumpers connecting the +LS sense terminal to the +S analog connector pin and
the -LS sense terminal to the -S analog connector pin. The power supply is shipped with these jumpers connected.
Connecting the Sense Leads
You must connect the positive side of the load to the +S analog connector pin and the negative side of the load to the -S
analog connector pin (see Figure 4-3). Connect the sense leads carefully so that they do not become open-circuited. If sense
leads are left open during operation, the supply will regulate at the output terminals instead of at the load. Remember to
bundle or tie wrap the load leads to minimize inductance and reduce noise pickup.
CV Regulation
The voltage load regulation specification in “Performance Specifications” applies at the output terminals of the power
supply. When remote sensing, this specification must be compensated as follows.
Series 654xA and 655xA Supplies
Add 3 mV to the voltage load regulation specification for each 1-volt change in the positive load lead due to a change in
load current. Because the sense leads are part of the supply's feedback path, keep the resistance of the sense leads at or
below 0.5 Ω to maintain the above specified performance.
Series 657xA Supplies
Add an increment to the voltage load regulation specification as specified by “∆mV” in the equation given under Load
regulation in Table 1-2b.
Output Rating
The rated output voltage and current specification in “Performance Specifications” applies at the output terminals of the
power supply. With remote sensing, any voltage dropped in the load leads causes the supply to increase the voltage at the
output terminals so it can maintain the proper voltage at the load. When you attempt to operate at the full-rated output at the
load, this forces the supply voltage at the output terminals to exceed the supply's rated output. This will not damage the
supply, but may trip the OVP (overvoltage protection) circuit, which senses the voltage at the output. When operated
beyond its rated output, the supply's performance specifications are not guaranteed, although typical performance may be
good. If the excessive demand on the supply forces it to lose regulation, the Unr annunciator will indicate that the output is
unregulated.
User Connections and Considerations 45
Output Noise
Any noise picked up on the sense leads also appears at the output of the power supply and may adversely affect the load
voltage regulation. Be sure to twist the sense leads to minimize external noise pickup and route them parallel and close to
the load leads. In noisy environments, it may be necessary to shield the sense leads. Ground the shield only at the power
supply. Do not use the shield as one of the sense conductors
Note
Agilent 657xA Series - The signal ground binding post on the rear panel is a convenient place to ground
the sense shield.
Stability
Using remote sensing under unusual combinations of load-lead lengths and large load capacitances may cause your
application to form a low-pass filter that becomes part of the voltage feedback loop. The extra phase shift created by this
filter can degrade the supply’s stability and result in poor transient response. In severe cases, this may cause output
oscillations. To minimize this possibility, keep the load leads as short as possible and tie wrap them together.
In most cases, following the above guidelines will prevent problems associated with load lead inductance. This leaves load
load-lead resistance and load capacitance as the major source of reduced stability. Further improvement to the stability of
the supply may be obtained by keeping the load capacitance as small as possible and by decreasing the load-lead resistance
by using larger diameter wires. However, if heavy gauge wire (≥AWG 10) is used, conditions may arise where the load-lead
inductance and load capacitance can form an undamped filter. This can actually reduce the damping in the system and create
a destabilizing phase response.
Note
If you need help in solving a stability problem with any Series 654xA, 655xA, or 657xA supply, contact
an Agilent Service Engineer through your local Agilent Sales and Support office.
Series 657xA Network
If a large bypass capacitor is required at the load and the load-lead length cannot be reduced, then a sense-lead bypass
network may be needed to ensure stability (see Figure 4-5). The voltage rating of the 33 µF capacitors should be about 50%
greater than the anticipated load-lead drop. Addition of the 20-Ω resistors will cause a slight voltage rise at the remote
sensing points. For utmost voltage programming accuracy, the supply should be recalibrated with the DVM at the remote
sensing points (see Appendix A).
Figure 4-5. Series 657xA Sense Lead Bypass Network
46
User Connections and Considerations
Operating Considerations
Auto-Parallel Operation
Auto-Parallel Wiring
Figure 4-6 illustrates how power supplies can be connected in auto-parallel for increased current output. You can connect
supplies of the same model in auto-parallel as follows:
•
•
Series 654xA or 655xA - up to three supplies.
Series 657xA - up to five supplies.
Use load leads of a sufficient wire size so that the absolute voltage difference between the + output terminal of the “master”
supply and the + output terminal of the first “slave” supply is kept under 2 V at rated current. This also applies to the
voltage difference between the + output terminals of the first and second slave supplies. If remote sensing is required,
connect the load to the remote sense terminals of the master supply, as shown by the dashed lines in Figure 4-6.
Note
To avoid output oscillations with Series 654xA and 655xA supplies, observe the wiring suggestions given
under “External Voltage Control”.
Figure 4-6. Connecting Power Supplies in Auto-Parallel
User Connections and Considerations 47
General Auto-Parallel Programming
Program only the first (“master”) supply in the series; the “slave” supplies automatically track the master's output. However,
the voltage and OVP settings of the slave supplies must be set higher than the operating voltage of the master supply. This
ensures that the slave supplies will operate in CC mode.
Series 654xA and 655xA Auto-Parallel Programming
Follow the following operating precautions if you are connecting three of these models in auto-parallel.
You must use caution when connecting three Series 654xA and 655xA power supplies for auto-parallel operation. That is
because of the OVP crowbar circuits within these supplies. If the OVP circuit of the second “slave” trips, its crowbar circuit
will draw current from the other two supplies. Although some models can withstand this current, the higher-current models
in each series (particularly the Agilent 6651A) may be damaged in this situation. Use any of the following operating
techniques to avoid possible problems.
Program Slave 2 OVP to the Maximum Level.
The following technique minimizes the chance that the slave 2 OVP circuit will trip.
1.
2.
Program the OVP level of the master and of slave 1 to the desired protection level (below the maximum level specified
in Table 1-2b).
Program the OV protection level of slave 2 to its maximum value.
Enable OCP on the Master.
You can do this if the combination of all three supplies is being used in the CV mode and the CC mode is only being used as
a current limit. Enable OCP on the master supply. If the OVP on either slave trips it will drive the master into CC mode,
thereby tripping its OCP. This will shut down all three supplies. This technique will work unless the system is programmed
for very low (0.5 to 1.5) output voltages.
Insert Protection Diodes.
If you connect the slave 2 supply to the load through a series diode (see Figure 4-7), its OVP circuit will not draw current
from other supplies. Be certain to increase the programmed CV level of slave 2 by at least 0.7 V to compensate for the
voltage drop in the diode.
Figure 4-7. Using Series Diodes with Series 654xA/655xA Auto-Parallel Operation
Note
48
Removing or disabling the power supply OVP crowbar SCR is another possibility. For further
information, contact an Agilent Service Engineer through your local Agilent Sales and Support office.
User Connections and Considerations
Series Operation
Floating voltages must not exceed 240 Vdc. No output terminal may be more than 240 V from chassis
ground.
Figure 4-8 shows how power supplies can be connected in series for higher voltage output. Series connections are
straightforward in this case.
Program each power supply independently. If two supplies are used in the series configuration, program each supply for
50% of the total output voltage. Set the current limit of each supply to the maximum that the load can handle without
damage.
Figure 4-8. Connecting Power Supplies in Series
Each power supply has a reverse voltage protection diode across its output. If a reverse voltage is
applied, the supply cannot control the current conducted through this diode. To avoid damaging the
supply, never connect it in such a way that a reverse voltage can force it to conduct current in excess of
the supply's maximum reverse diode current (see “Supplemental Characteristics”).
External Voltage Control
The setup shown in Figure 4-9 allows an external dc voltage to program the power supply output. A voltage applied to the
voltage programming input programs the output voltage and a voltage applied to the current programming input programs
the output current. See Figure 4-3 and Table 4-1 for an explanation of these programming input connections.
Programming Series 654xA and 655xA Supplies
Wiring Considerations
The input impedance of the analog input is 10 kΩ. If the output impedance of your programming source is not negligible
with this, programming errors will result. Larger output impedances result in proportionally greater errors.
Be careful of capacitive coupling from the programming inputs to other lines wired to the analog connector. Such coupling
can cause output oscillations. You can minimize coupling by bundling the IP, VP, and Common P lines and keeping them
separated from other wires. Twisting these three lines together is also recommended.
User Connections and Considerations 49
Figure 4-9. External Voltage Programming
If you cannot avoid capacitive coupling, it may help to place capacitors from the unused programming inputs to ground.
Especially with auto-parallel operation, connecting a capacitor (≥4,000 pF) from VP to P Common on the master supply
will ensure proper operation. Also with auto-parallel operation, do not allow more than about 500 pF capacitive loading
between IM and Common P.
Programming Considerations.
When voltage programming the output, the frequency of the programming source is limited by the slew rate of the power
supply. To keep the power supply from slewing its output (going into nonlinear operation), the maximum programming rate
is 3750 V/s. The maximum downprogramming rate (when the power supply is sinking current) is 750 V/s. These restrictions
can be expressed as the maximum programming frequency that can be applied without causing distortion at the output. The
following formula can be used to determine this frequency:
FMAX =
50 (voltage rating of supply)
p - p amplitude of desired output sine wave
At frequencies >6 kHz, voltage programming is subject to a 3 dB bandwidth limitation.
50
User Connections and Considerations
Programming Series 657xA Supplies
Wiring Considerations.
The input impedance of the analog input is over 30 kΩ. If the output impedance of your programming source is not
negligible with this, programming errors will result. Larger output impedances result in proportionally greater errors.
Note from Figure 4-3 that you have three options for programming the current. You can use a voltage source that is positive,
negative, or floating with respect to Common P. Do not exceed ±19 V with respect to Common P.
Make sure that the common connection for your voltage programming source is isolated from the load.
Failure to do this may cause damage to the power supply.
OVP Considerations
Remote Sensing
The OVP circuit senses the voltage near the output terminals and not at the sense terminals. Depending on the voltage drop
between the output terminals and the load, the voltage sensed by the OVP circuit can be significantly higher that that
actually being regulated at the load. You must program the OVP trip high enough to compensate for the expected higher
voltage at the output terminals.
Battery Charging
The power supply’s OVP circuit contains a circuit that discharges the output of the supply whenever the OVP trips. If a
battery (or other external voltage source) is connected across the output and the OVP is inadvertently triggered or the output
is programmed below the battery voltage, the power supply will continuously sink a large current from the battery. This
could damage the supply. To avoid this, insert a reverse blocking diode in series with the + output of the supply. Connect
the diode cathode to the + battery terminal and the diode anode to the supply + output terminal. The diode may require a
heat sink.
Series 654xA and 655xA Load Capacitance
For Series 654xA and 655xA power supplies, the OVP circuit has been designed to discharge fully-charged capacitances up
to a specified limit for each model. These limits are as follows:
6541A
700,000µF
6542A
35,000µF
6543A
15,000µF
6544A
7,000µF
6545A
3,000µF
6551A
1.6F
6552A
100,000µF
6553A
50,000µF
6554A
18,000µF
6555A
8,000µF
If a load capacitance approaches the specified limit, it is recommended that you do not make it a normal practice of tripping
the OVP circuit and discharging the load capacitance through that circuit. This could cause long-term fatigue in some circuit
components.
Because of its high output voltage, the Agilent 6555A generates very high currents when discharging
the load capacitor under overvoltage conditions. Excessive currents can damage the supply. The peak
discharge current is limited by the sum of the external capacitor’s ESR (equivalent series resistance) and
the series resistance of the external circuit. For the Agilent 6555A’s external capacitance limit of 8,000
microfarads, this total resistance must be not less than 56 milliohms. For smaller values of external
capacitance, this resistance may be derated linearly.
User Connections and Considerations 51
5
Front Panel Operation
Introduction
This chapter shows you how to operate the front panel. It is assumed that you are familiar with the turn-on checkout
procedure in Chapter 3. That chapter describes how to perform basic power supply functions from the control panel.
Operations that you can perform are:
•
•
•
•
•
•
•
Enabling or disabling the power supply output.
Setting the output voltage and current.
Monitoring the output voltage and current.
Setting the overvoltage protection (OVP) trip point.
Enabling the overcurrent protection (OCP) circuit.
Saving up to 5 operating states in nonvolatile memory.
Recalling up to 5 operating states from nonvolatile memory.
Note You also can calibrate the power supply from the front panel (see Appendix A).
Getting Acquainted
The front panel is summarized in Figure 5-1. Note that the panel is organized as follows:
① LCD display (including annunciators)
② Output VOLTAGE and CURRENT rotary (RPG) controls
③ SYSTEM keys
④ FUNCTION keys
⑤ ENTRY keys
Power On-Off (LINE) switch
Some keys perform two operations. The first operation is shown on the key and the second (shifted) operation is shown in
blue above the key. In order to do a shifted operation, first press the solid blue key, which is unlabeled but shown
throughout this manual as
.
For example, for a recall operation, you press the recall key
. For a save operation, you press the save key, which is
. In this chapter, such a shifted operation may be shown simply as
.
The display consists of alphanumeric data and triangular-shaped annunciators (▼) along the bottom of the display.
Front Panel Operation 53
Table 5-1. Front Panel Controls and Indicators
Function or Indication
Control or
Indicator
VOLTS
AMPS
CV
CC
Unr
Dis
OCP
Prot
Err
Cal
Shift
Rmt
Addr
SRQ
1
1 Display
Shows present output voltage of the power supply.
Shows present output current of the power supply.
Status Annunciators
The power supply is in constant-voltage mode.
The power supply is in constant-current mode.
The power supply output is unregulated (output is neither CV or CC).
The power supply output is disabled.
The overcurrent protection function is enabled.
A protection circuit has caused the power supply to shut down. (Press
reason.).
(Not used1).
The power supply is in calibration mode.
has been pressed.
The shift key
(Not used1)
(Not used1)
(Not used1)
to determine the
These annunciators function only with the corresponding models of GPIB System family of power supplies.
Voltage
Current
2 Output Rotary Controls
Rotate clockwise to increase output voltage or program setting. Provides the same function as the
and
keys.
Rotate clockwise to increase output current or program setting. Provides the same function as the
and
keys.
3 SYSTEM Keys
(Not used2)
(Not used2)
(Not used2)
Press to restore a previously saved power supply state. Use ENTRY keys
through
to specify
.) Use the ENTRY keys to specify the
which location to recall. (Select by pressing
location where you want to store the state. You may use locations 0 to 4.
Note: Location 0 may contain the power supply turn-on state. See “Turn-On Operation” in this chapter.
Use to save the power supply's present state to nonvolatile memory. (Select by pressing
.)
Use the ENTRY keys to specify the location where you want to store the state. You may use locations 0
to 4.
This unlabeled blue key is the Shift key. Press to access the shifted (alternate) key functions.
2
These keys function only with the corresponding models of GPIB System family of power supplies. Pressing them causes
NO GPIB to be displayed.
54
Front Panel Operation
Control or
Indicator
Table 5-1. Front Panel Controls and Indicators (continued)
Function or Indication
4 Function Keys
Press to enable or disable the power supply output. This key toggles between the two states. The
disabled state programs the output to very low voltage and current settings.
Press to display the output voltage setting. After pressing
, you may use the ENTRY keys
to change the value.
Press to display the output current setting. After pressing
, you may use the ENTRY keys
to change the value.
When the Prot annunciator comes on, press
to see which protection circuit caused the
power supply to shut down. Response can be OC (overcurrent), OT (overtemperature), or OV
overvoltage). If no protection circuit has tripped, the display will show dashes (-- -- -- --)
Press this key to reset the protection circuit. If the condition that caused the circuit to trip has been
removed, the Prot annunciator will go off.
Press to enable or disable the power supply OCP trip circuit. This key toggles between the to states .
Press to display the OV trip voltage setting. After pressing
change the value.
, you may use the ENTRY keys to
5 ENTRY Keys
Press to increment the output voltage in the CV mode, or the voltage setting after you have pressed the
key.3
Press to decrement the output voltage in the CV mode, or the voltage setting after you have pressed the
key.3
Press to increment the output current in the CC mode, or the current setting after you have pressed the
key.3
Press to decrement the output current in the CC mode, or the current setting after you have pressed the
key.3
3
The four incremental keys operate in two modes. Press and release for a single output change determined by the control
resolution (see ‘Supplemental Characteristics” in Chapter l). Press and hold for an increasingly rapid output change.
Press to select numerical values.
thru
Press to enter a minus sign.
Press to delete the last keypad entry. Use this key to correct one or more incorrect digits before they are
entered.
Press to delete an entire keypad entry and return to the meter mode. Use this key to exit from a value
before it is entered.
Press to enter a value or to accept an existing value and return the display to the meter mode.
The remaining shifted keys are for calibration (see Appendix A).
Front Panel Operation 55
Figure 5-1. Front Panel Controls and Indicators
Programming The Output
Introduction
Important
These instructions show how to program a single power supply. There are special
considerations when you have two or more supplies connected in series or in auto-parallel. See “Chapter 4
- User Connections and Considerations”.
The power supply accepts values directly in volts and amperes. Values will be rounded off to the nearest multiple of the
output resolution (see “Average Resolution” in “'Supplemental Characteristics” of Chapter 1). If you attempt to enter a
value not in a valid range, the entry will be ignored and OUT OF RANGE appears on the display.
Figure 5-2 shows the general response of a typical power supply. Note that the Series 654xA and 655xA supplies have a
small negative current area. This is for downprogramming purposes. Always keep the output current within the positive area
and within the boundaries of the particular operating line for the specified mode of operation (CV or CC).
Establishing Initial Conditions
Set the power supply to the following conditions by pressing the specified keys as required:
Zero voltage output
Minimal current output
Dis annuciator off
OCP annunciator off
Prot annunciator off
56
Front Panel Operation
(If needed)
(If needed)
(If needed)
Figure 5-2. Typical Power Supply Operating Curve
Programming Voltage
To program the output for 4.5 volts, proceed as follows:
■
■
■
Press
. The display will change from meter mode to indicate VOLTS.
. If you discover a mistake before pressing
, erase the incorrect value with the backspace
Press
key
.
The display will return to the meter mode and indicate 4.5000 volts.
Note
The power supply must be programmed for a minimal current in order to increase the output voltage
beyond zero. Normally, there is sufficient current to do this. If the power supply does not respond or the
Unr annunciator comes on, go to “Programming Current” and set the current to a small value.
Now raise the voltage by pressing
(or rotating the Voltage control clockwise). Note that the voltage increases by
a specific increment (depending on the voltage resolution) each time you press the key and increases rapidly as you hold
down the key. To lower the voltage, press
or rotate the Voltage control counterclockwise. Try to program a
voltage greater than the VMAX for your supply. Note that the display shows OUT OF RANGE.
Programming Current
Note
You may program the power supply current without a load, but must have a load in order to draw output
current. If you do not have a load on the power supply, you may connect a short across the output
terminals for this procedure. Turn the power supply off before making any connections.
To program the output current to 1.3 amperes, proceed as follows:
■ Make certain that the voltage is not programmed to zero.
■ Press
. The display will change from meter mode to indicate AMPS.
Front Panel Operation 57
■
■
. If you discover a mistake before pressing
, erase the incorrect value with the backspace
Press
key
.
The display will return to the meter mode and indicate up to 1.3000 amperes, depending upon the load.
Now raise the current by pressing
(or rotating the Current control clockwise). Note that the current increases by
a specific increment (depending on the current resolution) each time you press the key and increases rapidly as you hold
rotate the Current control counterclockwise.
down the key. To lower the current, press
Try to program a current greater than the IMAX for your supply. Note that the display shows OUT OF RANGE.
CV Mode vs. CC Mode
Once you program a voltage (Vs) and a current (Is), the power supply will try to maintain itself in either CV or CC mode,
depending on the resistance of the load (RL). If the load demands less current than Is, operation will be in CV mode with the
voltage maintained at Vs. The output current will be at some value below Is as determined by Vs ÷ RL.
For an Agilent 6552A supply, IMAX = 25.594 amperes and V MAX = 20.475 volts. If you program the output for <≤25
amperes at 20 volts, the supply will operate in the CV mode for all resistances >0.8 ohms. This represents the operating
resistance shown as RL = C in Figure 5-2. The supply will vary the output current to maintain a constant voltage of 25 volts.
If the load resistance is <0.8 ohms, the supply will vary its output voltage to maintain a constant current output of 25
amperes. However, if you reprogram the output voltage to a lower value Vs (see Figure 5-2), then the supply will again be
able to maintain CV operation with the lesser load resistance, such as RL=B in Figure 5-2.
Programming Overvoltage Protection
Overvoltage protection guards the load against voltages that reach a specified value above the programmed output voltage.
Setting the OVP Level
Assuming that a power supply is programmed for 10 volts, you can set the OVP level to 11.5 volts as follows:
■
■
■
■
■
Press
. The display will change from meter mode to indicate 0V, followed by the present OVP value.
.
Press
The display will return to the meter mode and indicate the output (10.000 volts).
Press
again. The display will now indicate 0V 11. 500.
Press
to return to the meter mode.
Checking OVP Operation
Assuming the above operating conditions, trip the OVP circuit as follows:
•
•
•
•
58
Raise the output voltage close to the trip point, such as 11.0.
Gradually increase the output voltage by pressing
until the OVP circuit trips. This will cause the output
voltage to drop to zero and the Prot annunciator to go on.
There now is no power supply output due to an overvoltage condition.
To verify this, press
and observe that the display indicates 0V.
Front Panel Operation
Clearing the OVP Condition
With the OVP tripped, return to the meter mode and try to clear the condition by pressing
. Nothing will appear
to happen because the CV trip point is still below the programmed output voltage. Thus, as soon as the circuit is cleared, it
trips again. You can clear the OV condition by:
• lowering the output voltage below 11.5 (the OV setting),
• or by raising the OV trip voltage above the output voltage setting.
Try either of these methods. Now when you press
, the Prot annunciator will go off and the output voltage will
return to normal.
Note In Series 654XA and 655XA supplies, the OVP circuit shorts the power supply output through
an SCR. If the load maintains current through the SCR, the above methods will not clear an OVP trip
condition. You must first remove the external current source before attempting to clear OVP.
Programming Overcurrent Protection
When enabled, overcurrent protection removes the power supply output whenever it goes into CC operation. This prevents
the supply from indefinitely supplying the full programmed current to the load.
Setting the OCP Protection
To activate overcurrent protection, press
. The OCP annunciator will come on and power supply will continue to
operate normally until it is forced into CC operation. If that occurs, the power supply will remove its output.
Checking OCP Operation
The easiest way to check this operation at any specified current is to place a short across the output. If the supply is
connected to an Agilent Electronic Load, press its key. The power supply output will then drop to zero and the Prot
annunciator will come on.
There is now no power supply output due to an overcurrent condition. To verify this, press
display indicates 0C.
and observe that the
Clearing the OCP Condition
. Nothing will appear
With the OCP tripped, return to the meter mode and try to clear the condition by pressing
to happen because the reason for the condition has not been removed. Thus, as soon as the circuit is cleared, it trips again.
You can clear the OC condition by:
•
•
increasing the load resistance to lower the output current below the programmed current value,
or by raising the programmed current to a value above that required by the load.
In this example, the easiest way to clear the OCP fault is by removing the short from across the output. After doing this, you
clear the OVP circuit by pressing
. The Prot annunciator will go off and the power supply output will be
restored to normal.
If desired, you can also restore the output by disabling the OCP function (press
to turn off the OCP annunciator.
This restores the output but does not clear any condition that may have caused OCP to trip.
Front Panel Operation 59
Note
Under certain conditions, the OCP circuit may fail to clear because load demand occurs before the power
supply has time to build up the required output current capacity. In such cases, disable the output (press
)before clearing the OCP circuit. After OCP is cleared, enable the power supply output.
Unregulated Operation
If the power supply goes into a mode of operation that is neither CV nor CC, the Unr annunciator will come on. An
unregulated condition limits the output current to a value that is safe for the supply. Some unregulated states occur so briefly
that they do not turn on the Unr annunciator. One condition that can cause a noticeable unregulated state is low ac line
voltage.
Saving and Recalling Operating States
Normal Operation
You can save programming time by storing up to 5 power supply operating states in nonvolatile memory. The programming
parameters that are saved are:
•
•
Output voltage Output current *OVP voltage
OCP state (on or off) Output state (enabled or disabled)
As an example, set up the following state:
•
•
Voltage = 4 V Current = 1 A OVP voltage = 5.5 V
OCP = on (OCP annunciator on) Output = Off (Dis annunciator on)
Save the above state to location 1 by pressing
.
Now set up the following state:
•
•
Voltage = 8 V Current = 1.5 A OVP voltage = 8.5 V
OCP = off (OCP annunciator off) Output = On (Dis annunciator off)
Save the above state to location 2 by pressing
.
Now restore the first state by pressing
and verify the parameters. Restore the second state by pressing
. Note how the power supply is automatically programmed each time.
Turn-On Operation
Whenever you apply power to a new power supply it automatically turns on in a safe reset state with the following
parameters:
•
•
off
maximum
minimum
off
near zero
It is recommended that you leave the turn-on conditions as programmed. However, you may change them if you wish. To do
this, proceed as follows:
1.
60
Set up the power supply to the state you want when it is turned on.
Front Panel Operation
2.
3.
4.
5.
Store that state to location 0.
Turn off the power supply.
Hold in the
key and turn the power supply back on. The display indicates RCL O PWR-ON to verify that the power
supply has configured its turn-on state to that stored in location 0.
From now on the supply will always turn on to the state defined in location 0.
Whenever you wish, you can return the power supply to the original factory reset state. To do this, simply hold down the
key when you turn on the supply. The display indicates RST PWR-ON to verify that the power supply has configured its
turn-on state to the original reset state. From now on it will continue to turn on in that state.
Front Panel Operation 61
A
Calibration
Introduction
The power supply may be calibrated from the front panel. The procedures given here apply to all models.
Important
These instructions do not include verification procedures. If you require verification as part of your
calibration procedure, refer to the appropriate service manual (see Table 1 -3 in Chapter 1).
Equipment
The equipment listed in Table A-1, or equivalent, is required for calibration.
Table A-1. Equipment Required for Calibration
Characteristics
Recommended Model
D-c accuracy 0.005%, 6 digits
Agilent 3456A or 3458A
Equipment
Voltmeter
Shunt Resistor
Agilent 6541A
Agilent 6542A, 43A, 44A ,45A
Agilent 6551A, 52A
Agilent 6553A, 54A, 55A
Agilent 6571A
Agilent 6572A,73A,74A,75A
0.01 Ω, 0.04%, 100 A, 100 W
0.1 Ω, 0.04%, 15 A, 100 W
0.01 Ω, 0.04%, 100 A, 100 W
0.1 Ω, 0.04%, 15 A, 100 W
0.001 Ω, 0.04%, 300 A, 100 W
0.01 Ω, 0.04%, 100 A, 100 W
Guildline 9230/100
Guildline 9230/15
Guildline 9230/100
Guildline 9230/15
Guildline 9230/300
Guildline 9230/100
General Procedure
Because the power supply output must be enabled during calibration, voltages or currents hazardous to
personnel and/or dangerous to equipment can appear at the output terminals.
Parameters Calibrated
You can calibrate the voltage output and readback, the current output, and the OVP trip function. The normal procedure is
to calibrate voltage first, then current. However, you do not have to do a complete calibration each time. If required, you
may calibrate only the voltage or the current and then proceed to “Saving the Calibration Constants”.
If you want to calibrate the OVP trip function, the power supply will do it automatically via firmware and store the OV
calibration constant. The voltage output must be in calibration before the OV trip voltage is calibrated.
Calibration 63
Equipment Connections
For voltage calibration:
•
•
•
Disconnect all loads from the power supply.
Connect the supply for local sensing (see Figure 4-1 or Figure 4-2).
Connect a DVM across the output terminals.
For current calibration:
•
•
•
Disconnect all loads from the power supply.
Connect the appropriate shunt resistor across the output terminals (see Table A-1).
Connect a DVM across the sense termina1s of the shunt resistor.
For OVP Calibration
•
None (The firmware performs the calibration based on the voltage calibration constants.)
Note
You can exit the calibration procedure at any time without changing the existing calibration constants. To
do this, press
.
Performing The Calibration
Seven shifted keys and the Entry keypad are used for calibration functions (See “Chapter 5 - Front Panel Operation” for an
explanation of shifted keys and the keypad). The following procedures assume you understand how to operate the front
panel keys and that the test equipment is connected.
Entering the Calibration Values
Use the procedure in Table A-2 for entering new calibration values.
Saving the Calibration Constants
Storing the calibration constants overwrites the existing ones in nonvolatile memory. If you are not
absolutely sure that you want to store the new constants, omit this step. The power supply calibration
constants then will remain unchanged.
To replace any existing calibration constants with ones you have just entered, press
on the display.
. CAL SAVED then appears
Changing the Calibration Password
You can change the password only when the module is in the calibration mode (which requires you to know the present
password). When in this mode, proceed as follows:
1.
2.
3.
4.
64
.
Press
In response to the prompt, enter the new password. It can be up to 6 integers or 6 integers and a decimal point. If you
enter more than the permitted number of integers, the extra ones will be ignored.
AGAIN will appear on the display. Enter the new password a second time.
When OK is displayed, you have changed the password. You do not have to save it. Press
to return to the
meter mode.
Calibration
Table A-2. Typical Calibration Procedure
Action
Enabling the Calibration Mode
1. Begin calibration by pressing
.
2. Enter calibration password from Entry keypad.
If password is correct the Cal annunciator will come on.
If password is incorrect, an error occurs. 2
Note: The initial (factory-default) password is the model number of the power supply, but it can be
changed (see “Changing the Password”).
Display
Response
PASWD1
PASSSWD ERROR
Entering Voltage Calibration Values
Make certain the DVM is the only load on the power supply.
Select the first calibration point by pressing
.
If the power supply is not in CV mode, an error occurs.
3. Read the DVM and use the Entry keypad to enter the first voltage value.
4. Select the second calibration point by pressing
again.
5. Read the DVM and use the Entry keypad to enter the second voltage value.
Note: If one of the entered values is not within acceptable range, an error occurs. The power supply
is now holding the new voltage calibration constants in RAM.
(Meter mode)
VRDG1
WRONG MODE
(Meter mode)
VRDG2
(Meter mode)
CAL ERROR
Calibrating the OVP Trip Point
1. Make certain the voltage has been calibrated and there is no load on the power supply.
2. Select OVP calibration by pressing
.
3. Wait for the power supply to compute the OVP calibration constant.
If the supply goes unregulated or into CC mode during OVP calibration, an error occurs.
If the computed constant is out of acceptable range, an error occurs.
(Meter mode)
OVPCAL
CAL COMPLETE
N0T CV M0DE
DOES NOT CAL
1.
2.
The power supply is now holding the new OVP calibration constant in RAM.
Entering Current Calibration Values
Make certain appropriate shunt resistor (see Table A-1) is the only load on the power supply.
Select the first calibration point by pressing
.
If the power supply is not in CC mode, an error occurs.
3. Read DVM and compute the first current value (DVM reading divided by shunt resistance).
(Wait for DVM reading to stabilize).
4. Use Entry keypad to enter the first current value.
5. Select second calibration point by pressing
again.
6. Read DVM and compute the second current value (DVM reading divided by shunt resistance).
(Wait for DVM reading to stabilize)
7. Use Entry keypad to enter the second current value.
Note: If one of the entered values is not within acceptable range, an error occurs.
1.
2.
(Meter mode)
IRDG1
WR0NG M0DE
(Meter mode)
(Meter mode)
IRDG2
(Meter mode)
(Meter mode)
CAL ERROR
The power supply is now holding the new current calibration constants in RAM.
1
If CAL DENIED appears, then an internal jumper has been set to prevent the calibration from being changed.
(See the Service Manual.)
2
If the active password is lost, the calibration function can be recovered by moving an internal jumper that defeats
password protection. However, this also will change all calibration constants to their factory-default values. (For
more information, see the Service Manual.)
Note
If you want
to operate without requiring any password, change the password to 0 (zero).
Calibration 65
Disabling the Calibration Mode
. The display will return to the meter mode with the Cal annunciator off.
To disable the calibration mode, press
If you shut off the power supply with calibration enabled, it will be disabled when you turn it back on.
Calibration Error Messages
The following error messages may appear during calibration:
CAL ERR0R
D0ES N0T CAL
PASSWD ERROR
WR0NG M0DE
66
Calibration
Table A-3. Calibration Error Messages
An entered value is not within acceptable range.
Computed calibration constant is out of range.
You entered an incorrect password.
The power supply is not in CV or CC mode, as required.
B
Line Voltage Conversion
Series 654xA and 655xA Power Supplies
Hazardous voltage can remain inside the power supply even after it has been turned off. This procedure
should be done only by qualified electronics personnel.
Provisions for converting the operating line voltage are provided inside the power supply.
These provisions are:
•
•
Series 654xA supplies: voltage select switches.
Series 655xA supplies: voltage select jumpers.
You must also change the power fuse to correspond to the new line voltage setting. If you need a different power cord,
contact your nearest Agilent Sales and Support Office.
Proceed as follows:
1.
2.
3.
4.
5.
6.
7.
Turn off the ac power and disconnect the power cord.
Remove the four screws securing the carrying straps and dustcover.
Slide the dustcover back far enough to expose the line select switches (see Figure B-l) or the line select jumpers (see
Figure B-2).
On a Series 654xA supply, move the line select switches to the positions corresponding to the desired voltage (see
Figure B-1).
On a Series 655xA supply, move the line select jumpers to the positions corresponding to the desired voltage (see
Figure B-2).
To disconnect it from the transformer tab, pull the wire straight up. Do not wiggle the wire from side-to-side as
this can damage the tab.
Replace the top cover and secure the carrying straps.
Change the line fuse (on the rear panel) to the proper value for the new line voltage setting (see Table 1-3 in Chapter
1).
Figure B-1. Series 654xA Line Select Switches
Line Voltage Conversion 67
Figure B-2. Series 655xA Line Select Jumpers
Series 657xA Power Supplies
Hazardous voltage can remain inside the power supply even after it has been turned off. This procedure
should be done only by qualified electronics personnel.
Provisions for converting the operating line voltage are provided inside the power supply. .
These provisions are:
1.
2.
3.
4.
5.
6.
7.
8.
9.
Turn off the ac power and disconnect the power cord from the power source.
Remove the four screws securing the carrying straps and dustcover.
Spread the bottom rear of the dustcover and pull it back to disengage it from the front panel.
Slide the dustcover back far enough to expose the line select switch (see Figure B-3).
Observe the input rail LED under the RFI shield. If the LED is on, there is still hazardous voltage inside the supply.
Wait until the LED goes out (this may take several minutes) before proceeding.
Connect a dc voltmeter across test points TP1 and TP2. (It may be necessary to remove the RFI shield in order to reach
these test points. The shield is secured by four screws on each side.) When the voltmeter indicates 60 volts or less, it is
safe to work inside the power supply.
Locate the line selector switch and slide it to the desired position.
If you removed it in step 6, be sure to replace the RFI shield.
Replace the dustcover.
Figure B-3. Series 657xA Line Select Switch
68
Line Voltage Conversion
Index
A
airflow..........................................................................................................................................................................27
ampere capacity ...........................................................................................................................................................42
analog
connector ........................................................................................................................................................40, 42
connector wiring .............................................................................................................................................41, 42
port .................................................................................................................................................................13, 41
programming ....................................................................................................................13, 40, 50, 51, 57, 58, 59
programming frequency........................................................................................................................................51
programming slew rate .........................................................................................................................................51
programming voltage isolation .............................................................................................................................51
annunciators
Addr.....................................................................................................................................................................54
Cal..................................................................................................................................................................54, 64
CC ..................................................................................................................................................................12, 54
CV ..................................................................................................................................................................12, 54
Dis ............................................................................................................................................................32, 33, 54
Err........................................................................................................................................................................54
OCP .....................................................................................................................................................................54
Prot ....................................................................................................................................................33, 54, 58, 59
Rmt ......................................................................................................................................................................56
Shift................................................................................................................................................................35, 54
SRQ......................................................................................................................................................................54
Unr .................................................................................................................................................................54, 60
B
backspace key
..................................................................................................................................... 34, 55, 57
C
key .................................................................................................................................................64, 66
key.....................................................................................................................................................65, 66
key ..........................................................................................................................................................64
calibration password ..............................................................................................................................................37, 64
capacitive loads ...........................................................................................................................................................43
CC mode..............................................................................................................................................13, 43, 55, 57, 58
checkout
output....................................................................................................................................................................34
power-on...............................................................................................................................................................32
checksum error ............................................................................................................................................................37
key .......................................................................................................................................................55
Common P return.............................................................................................................................................41, 50, 51
CURRENT control.............................................................................................................................................12, 32, 55
key.............................................................................................................................................................55
,
keys .........................................................................................................................34, 55, 58
CV mode..............................................................................................................................................13, 43, 55, 57, 58
Index 69
D
default state (see factory-reset state)
downprogramming...........................................................................................................................................13, 50, 56
E
EEPROM.....................................................................................................................................................................37
key ................................................................................................................................................................55
key.................................................................................................................................................................54
errors............................................................................................................................................................................37
error messages
calibration.............................................................................................................................................................66
N0 GPIB.................................................................................................................................................................54
OL ...........................................................................................................................................................................................38
OUT OF RANGE...............................................................................................................................................56, 57
power-on...............................................................................................................................................................37
runtime..................................................................................................................................................................38
selftest...................................................................................................................................................................37
exhaust fan...................................................................................................................................................................28
external voltage control .........................................................................................................................................41, 49
F
factory-reset state.........................................................................................................................................................61
front panel
controls and indicators....................................................................................................................................12, 54
programming .................................................................................................................... 13, 32, 33, 56, 57, 58, 59
fuse, line ........................................................................................................................................25, 27, 28, 31, 35, 36
G
ground
chassis.............................................................................................................................................................42, 49
earth..........................................................................................................................................................11, 29, 42
safety ................................................................................................................................................................... 42
H
hardware ................................................................................................................................................................25, 27
I
key ...................................................................................................................................................................65
IM output .....................................................................................................................................................................41
impedance
output........................................................................................................................................................19, 20, 24
programming source .............................................................................................................................................50
inductive loads.............................................................................................................................................................43
initial conditions ..........................................................................................................................................................56
70 Index
IP input ..................................................................................................................................................................41, 50
±IP differential input....................................................................................................................................................41
isolation .................................................................................................................................................................42, 51
J
jumpers
calibration.............................................................................................................................................................65
line voltage selection ............................................................................................................................................68
local sense.............................................................................................................................................................40
L
load
capacitance ...........................................................................................................................................................43
electronic ..............................................................................................................................................................59
impedance.............................................................................................................................................................13
inductance.............................................................................................................................................................43
isolation ................................................................................................................................................................51
line........................................................................................................................................................................13
multiple.................................................................................................................................................................44
key.................................................................................................................................................................54
local sense switch (see switch, sense)
local sensing ..........................................................................................................................................................31, 44
±LS terminals...................................................................................................................................................31, 44, 45
M
manual change sheet ...................................................................................................................................................27
manual, instruction.................................................................................................................................................11, 25
N
N0 GPIB message..........................................................................................................................................................54
O
OC ..................................................................................................................................................................12, 55 ,59
OCP ........................................................................................................................................................................48,59
key, 5-2, 5-7
±OL .............................................................................................................................................................................38
OT .........................................................................................................................................................................12,55
output
characteristic.......................................................................................................................................13, 18, 23, 56
impedance...........................................................................................................................................19, 20, 24, 44
isolation ................................................................................................................................................................42
noise .....................................................................................................................................................................46
oscillations................................................................................................................................................46, 47, 50
rating...............................................................................................................................................................12, 46
ringing ..................................................................................................................................................................43
stability ...........................................................................................................................................................43, 46
Index 71
key............................................................................................................................................34, 55, 60
OV ............................................................................................................................................................12, 33, 55, 58
overcurrent protection (see OCP)
overvoltage protection (see OVP)
key ...................................................................................................................................................................55
key................................................................................................................................................................65
OVP
and battery charging .............................................................................................................................................51
and output capacitance .........................................................................................................................................51
and remote sensing ...............................................................................................................................................51
clearing .................................................................................................................................................................59
crowbar...........................................................................................................................................................48, 49
programming ........................................................................................................................................................58
protection diodes ..................................................................................................................................................48
SCR ................................................................................................................................................................49, 59
P
key ...................................................................................................................................................................64
power cord .......................................................................................................................................................11, 27, 29
power receptacle ..........................................................................................................................................................11
power options ..................................................................................................................................................11, 16, 21
key..............................................................................................................................................34, 55, 58, 59
key .................................................................................................................................................55, 59
PWR ON INIT message ..................................................................................................................................................32
R
rack mount kit........................................................................................................................................................11, 27
key ............................................................................................................................................................... 54
recalling states .......................................................................................................................................................45, 60
remote sensing .......................................................................................................................................................45, 51
remote sense switch (see switch, sense)
resistor, shunt (see shunt, calibration)
reverse voltage.............................................................................................................................................................49
RFI
shield ....................................................................................................................................................................36
suppression .....................................................................................................................................................17, 23
ringing, output, 4-5
RPG control (see CURRENT and VOLTAGE control)
RCL PWR-ON message..................................................................................................................................................61
RST PWR-ON message..................................................................................................................................................61
72 Index
S
±S inputs....................................................................................................................................................31, 41, 44, 45
safety class...................................................................................................................................................................11
safety compliance ..................................................................................................................................................17, 23
safety cover
output..............................................................................................................................................................25, 39
power cord............................................................................................................................................................29
safety warning........................................................................................................................................................11, 36
key.............................................................................................................................................................54, 60
saving states...........................................................................................................................................................35, 60
sense leads (see remote sensing)
serial number ...............................................................................................................................................................11
service manual .................................................................................................................................................11, 25, 65
shift key
.........................................................................................................................................34, 53, 54, 56
shunt, calibration .........................................................................................................................................................63
slide mount, rack..........................................................................................................................................................12
specifications .........................................................................................................................................................14, 21
supplemental characteristics ..................................................................................................................................15, 22
supplies in auto-parallel .........................................................................................................................................47, 48
supplies in series..........................................................................................................................................................49
support rails .................................................................................................................................................................27
switch
line voltage .....................................................................................................................................................67, 68
sense ...................................................................................................................................................31, 40, 44, 45
T
turn-on state
factory reset ..........................................................................................................................................................61
stored location 0 ...................................................................................................................................................60
U
unregulated output .......................................................................................................................................................60
V
key...................................................................................................................................................................65
verification tests.....................................................................................................................................................31, 63
VOLTAGE control .......................................................................................................................................12, 32, 54, 57
key ..........................................................................................................................................................55
keys.............................................................................................................33, 55, 57, 58
VP input.................................................................................................................................................................41, 50
W
wire size.......................................................................................................................................................................41
Index 73
Agilent Sales and Support Office
For more information about Agilent Technologies test and measurement products, applications, services, and for a current
sales office listing, visit our web site: http://www.agilent.com/find/tmdir
You can also contact one of the following centers and ask for a test and measurement sales representative.
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Technical data is subject to change.
Agilent Sales and Support Offices 75
Manual Updates
The following updates have been made to this manual since the print revision indicated on the title page.
4/01/00
All references to HP have been changed to Agilent.
All references to HP-IB have been changed to GPIB.