Service Manual
Agilent Model 66312A
Dynamic Measurement DC Source
and Agilent Model 6612B
System DC Power Supply
For instruments with Serial Numbers:
Agilent 66312A: US37442096 and up
Agilent 6612B:  US37470826 and up
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Agilent Part No. 5962-0874Printed in U.S.A. Microfiche No 6962-0875September, 2000
Warranty Information
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 for 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. S
PECIFICALLY 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 contacts, 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.
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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 manual violates safety standards of design, manufacture, and intended use of the instrument. Agilent Technologies, Inc. assumes no liability for the customer's failure to comply with these requirements.
WARNING
Servicing instructions are for use by service-trained personnel. To avoid dangerous electrical shock, do not perform any servicing unless you are qualified to do so. Some procedures described in this manual are performed with power supplied to the instrument while its protective covers are removed. If contacted, the energy available at many points may result in  personal injury. BEFORE APPLYING POWER.
Verify that the product is set to match the available line voltage, the correct  line fuse is installed, and all safety precautions (see following warnings) are taken. In addition, note the instrument's external markings described under "Safety Symbols" GROUND THE INSTRUMENT.
Before switching on the instrument, the protective earth terminal of the instrument must be connected to the protective conductor of the (mains) power cord. The mains plug shall be inserted only in an outle
t socket that is provided with a protective earth contact. This protective action must not be negated by the use of an extension cord (power cable) that is without a protective conductor (grounding). 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.
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.
KEEP AWAY FROM LIVE CIRCUITS.
Operating personnel must not remove instrument covers. Component replacement and internal adjustments must be made by qualified service personnel. Do not replace components with power cable connected. Under certain conditions, dangerous voltages may exist even with the power cable removed. To avoid injuries, always disconnect power, discharge circuits and remove external voltage sources before touching components.
DO NOT SERVICE OR ADJUST ALONE.
Do not attempt internal service or adjustment unless another person, capable of rendering first aid and resuscitation, is present. Any adjustment, maintenance, and repair of this instrument while it is opened and under voltage should be avoided as much as possible. When this is unavoidable, such adjustment, maintenance, and repair should be carried out only by a skilled person who is aware of the hazard involved.汽车维修手册下载
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, Inc.  Sales and Service Office for service and repair to ensure that safety features are maintained.
SAFETY SYMBOLS
Refer to the table on the following page
WARNING 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.
Caution 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.
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Safety Symbol Definitions
Symbol Description
Direct current
Alternating current
Both direct and alternating current
Three-phase alternating current
Earth (ground) terminal
Protective earth (ground) terminal
Frame or chassis terminal
Terminal is at earth potential (Used for measurement and control circuits designed to be
operated with one terminal at earth potential.)
Terminal for Neutral conductor on permanently installed equipment
Terminal for Line conductor on permanently installed equipment
On (supply)
Off (supply)
Standby (supply)
Units with this symbol are not completely disconnected from ac mains when this switch
is off. To completely disconnect the unit from ac mains, either disconnect the power
cord or have a qualified electrician install an external switch.
In position of a bi-stable push control
Out position of a bi-stable push control
Caution, risk of electric shock
Caution, hot surface
Caution (refer to accompanying documents)
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Notice
The information contained in this document is subject to change without notice. Agilent Technologies m
akes no warranty of any kind with regard to this material, including but not limited to, the implied warranties of merchantability, and fitness for a particular purpose.
Agilent Technologies shall not be liable for errors contained herein or for incidental or consequential damages in connection with the furnishing, performance or use of this material.
This document contains proprietary information which is protected by copyright.  All rights are reserved.  No part of this document may be photocopied, reproduced, or translated into another language without the prior written consent of Agilent Technologies.
ã Copyright 1997, 2000 Agilent Technologies, Inc.
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 m
anual. 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.
First Edition ............February, 1997
Second Edition ......  September, 2000
Instrument Identification
The power supply is identified by a unique serial number such as, US36310101. The items in this serial number are explained as follows:
US36310101The first two letters indicate the country of manufacture. US = United States.
The next four digits are the year and week of manufacture or last significant design change.
Add 1960 to the first two digits to determine the year. For example, 36=1996. The third and
fourth digits specify the week of the year (31 = the thirty-first week).
The last four digits (0101) are a unique number assigned  to each unit.
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