Service manual
 Introduction
 7
1
 Introduction
Scope and Organization
 This manual contains information for troubleshooting and repairing Agilent Series 669xA, 6.6-kilowatt power supplies to
the assembly level. The supplied schematics at the back of the manual are not intended for component level repair, only to
provide additional information for isolating a problem to a specific assembly. The chapters of this manual are organized as
follows:
 Chapter  Description
 Chapter 2  Verification procedures to determine the performance level of the supply either before or after repair.
 Chapter 3  Troubleshooting procedures for isolating a problem, procedures for replacing the defective assembly
and, if required, post-repair calibration and EEPROM initialization procedures.
 Chapter 4  Principles of power supply operation on a block-diagram level.
 Chapter 5  Assembly-level replaceable parts, including parts ordering information.
 Chapter 6  Diagrams, including schematics, component location drawings, and troubleshooting test points.
Instrument Identification
Agilent Technologies instruments are identified by a 10-digit serial number. The format is described as follows: first two
letters indicate the country of manufacture. The next four digits are a code that identify either the date of manufacture or of
a significant design change. The last four digits are a sequential number assigned to each instrument. 
 Item Description
 MY The first two letters indicates the country of manufacture, where US = USA; MY = Malaysia.
 3648 This is a code that identifies either the date of manufacture or the date of a significant design change.
 0101 The last four digits are a unique number assigned to each power supply.
Manual Revisions
 The edition and current revision of this manual is indicated on page 4. 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. Significant changes to the manual
occurring between revisions are covered by change sheets shipped with the manual. Note that not all changes made to the
power supply affect the content of the manual. Refer to appendix A for a history of manual updates.
This manual was written for power supplies that have the same serial prefixes (first part) as those listed on the title page and
whose serial numbers (second part) are equal to or higher than those listed in the title page.
Note
1)  A revised edition incorporates all new or corrected material since the previous printing date.
2)  If they are significant to the operation and/or servicing of the power supply, those differences are
documented in one or more Manual Changes sheets included with this manual. These changes will also
be incorporated at future updates of the manual.
3)  A history of changes to this manual that affect previously manufactured units is provided in Appendix A
- Manual Backdating.










