Agilent Technologies 6621A, Service Manual

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Section III
VERIFICATION
3-1 INTRODUCTION
This section contains test procedures that check the
operation of the power supply. Four types of procedures are
provided: Operation Verification Tests, Performance Tests,
Extended Tests, and Temperature Coefficient Tests.
The Operation Verification Tests comprise a short procedure
to verify that the supply is performing properly, without
testing all specified parameters. The Performance Tests
provide a more complete test of the supply by testing most
of the specifications listed in Table 1-1 in the Operating
Manual (Agilent Part No. 5957-6377).
The Extended and Temperature Coefficient tests are similar
to the Performance tests except that they are conducted in a
controlled environment and require a longer period of time
to complete each test.
If failures are encountered or out of specification test results
are observed, refer to the Troubleshooting Procedures in
Section IV in this manual. The troubleshooting procedures
Calibration procedures are provided in Appendix A of the
Operating Manual.
3-2 TEST EQUIPMENT REQUIRED
Table 3-1 lists the equipment required to perform the tests in
this section. The tests are performed by sending commands
front panel and, consequently do not require use of a
controller.
The tests should only be performed by qualified
personnel. During the performance o f these tests,
the output o f the supply being tested may reach
voltage levels above safe levels.
3-3 OPERATION VERIFICATION TESTS
a. Perform the turn-on and checkout procedures given in
Section III of the Operating Manual. These procedures
include a power-on self test.
b. Perform the performance tests listed below on each
output of your supply.
Voltage Programming and Readback Accuracy
(paragraph 3-12)
CV Load Effect (paragraph 3-13 )
CV Noise (paragraph 3-15)
Overvoltage Protection Tests (paragraph 3-20)
Current Programming and Readback Accuracy
(paragraph 3-23)
CC Load Effect (paragraph 3-25)
3-4 PERFORMANCE TESTS
3-5 Introduction
The following paragraphs provide test procedures for
verifying the supply's compliance with the specifications
listed in Table 1-1 of the Operating manual. The procedures
The test procedures that follow give settings and results for
each type of output that may be tested. There are four types
of outputs: 40 Watt Low Voltage (40WLV), 40 Watt High
Voltage (40WHV), 80 Watt Low Voltage (80WLV), and 80
Watt High Voltage (80WHV). Make sure that you use the
test settings and results listed for the particular output being
tested. It is recommended that the tests be performed in the
sequence given, and that all data be recorded on the test
record provided at the end of the test procedures (see
paragraph 3-28).
3-6 Measurement Techniques
3-7 Setup for All Tests. Measure the dc output voltage
directly at the + S and - S terminals of the output under test.
Connect the output for local sensing and use adequate wire
gauge for load leads as described in Section IV of the
Operating Manual.
Many of the test procedures require the use of a variable
load resistor capable of dissipating the required power (see
Table 3-1). Using a variable load resistor requires that
switches be used to connect, disconnect, and short the load
resistor. An electronic load, if available, can be used in place
of a variable load resistor and switches. The electronic load
3-1
will determine if repair and/or calibration is required.
cover Agilent Models 6621A through 6624A and 6627A in
the series of Multiple Output Power Supplies. The
performance test procedures must be performed on each
output. Figure 3-1 shows the outputs present and output
ranges on each model.
To assure that all outputs of your supply are performing
properly, without testing all specified parameters, perform
the test procedures outlined.
to and receiving data from the supply under test via the
GPIB. An Agilent 9825, 85, or series 200 computer is used as
the GPIB controller. Tests that do not verify readback via the
GPIB can also be performed manually from the supply's