User`s guide

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230 N1911A/1912A P-Series Power Meters User’s Guide
Remote Testing
To invoke the remote self test, the IEEE 488.1 compliant standard
command, *TST? is used. This command runs a full self test and returns
one of the following codes:
•0 -no tests failed
• 1 - one or more tests failed
The remote self test consists of the following tests:
The communications assembly is tested implicitly, in that the command
will not be accepted or return a result unless the remote interface is
functioning correctly.
Refer to “Test Descriptions” on page 230 if you require a description of
each individual test.
When the *TST? command is executed, the screen is cleared. As each test
takes place, the name of the test is listed on the screen. While a test is
running, the message Testing... appears beside the name of the test. As
each stage of the test is completed, the message Testing... is replaced by
either the message Passed or Failed.
Test Descriptions
This section specifies what is actually checked by each of the tests. Some
of the tests may only be applicable to one method of invocation (for
example, from the front panel). If this is the case, it is specified in the
test description. Most of the tests have an associated error message which
is added to the error queue if the test fails. The exception to this is the
bitmap display test. Refer to “Error Messages” on page 232 for more
details.
Fan
This test confirms that the internal cooling fan is operating.
Calibrator
The reference calibrator is turned on (indicated by the POWER REF LED)