Fluke 9640A Series, Instruction Manual

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Maintenance
User-Initiated Self Test
7
7-19
User-Initiated Self Test
The Instrument includes a self-test feature that functions as an operational self-test when
the unit is initially powered on and later as a more comprehensive user-initiated test. The
simpler version of the self test is described in Chapter 2, Preparing the Instrument for
Operation . This section of the manual addresses the more complex version of the self
test. Discussions include an overview of what the self test checks for, instructions for
running the self test, and instructions for analyzing the results of a self test. Collectively,
the discussions help the user confirm whether the Instrument is working properly and, if
not, help the user isolate and troubleshoot the problem to a module level.
In operation the self test is initiated by the user, either from the front panel or from an
IEEE 488 controller. Once initiated, the test runs automatically and progresses as follows:
1.
The test runs the Instrument through a series of test points.
2. Each test point configures the instrument internally.
3. The Instrument makes a test-point measurement using an internal ADC, sensors, and
detectors.
4. The Instrument compares the result of each test point with pre-determined limits.
Test points that fail (exceed) these limits can be viewed using the front panel and will
include the test point description, the measured value, and the preset (acceptable) limits.
The measured value will usually be displayed as the voltage present at the point being
measured.
To enhance the usefulness of the self test as a troubleshooting tool, it can be run as three
separate sequences: Base, Head and All. The Base sequence is a test of the Instrument
only, with or without the Leveling Head attached. The Head sequence is a test of only the
Leveling Head while it is attached to the Instrument. The All sequence performs a test of
both the Instrument and the attached Leveling Head.
Running Self Test
The following instructions for the self test are given in terms of button presses from the
front panel. The same instructions may also be initiated using IEEE 488 instructions in a
system environment.
Note
The Base level self test may be run with or without a Leveling Head
attached. However, when a Leveling Head is attached ensure that the
Leveling Head output is disconnected during self test and that there are no
earth connections to the floating RF common. This includes the Leveling
Head body & the top two rear BNC connectors.
Use the following procedure to run a self test:
1.
Prepare the Instrument for operation as described earlier in Chapter 2.
2. Press

.
3. Press the
Self Test
soft key at the bottom of the display.
The following
Self Test
screen appears. The screen shows that no tests have been
executed and provides for the selection of the self-test sequence to run,
All
,
Base
, or
Head
.