Introduction; Performance Test Card; Calibration Cycle; Input Terminals/Control - HP 3455A Operating And Service Manual

Model 3455A
Section IV
SECTION IV
PERFORMANCE TESTS
4-1, INTRODUCTION.
4-2. This section contains performance and operational
verification test procedures which can be used to verify
that the 3455A meets its published specifications (listed
in Table 1-1). All tests can be performed without access
to the interior of the instrument. The performance tests
in this section do not test the 3455A Math Functions or
HP-IB Interface. These functions can be tested using
the operators test procedures included in Section III.
4-3. EQUIPMENT REQUIRED.
4-4. The test equipment required for the performance
tests is listed at the beginning of each procedure and in
the Recommended Test Equipment Table in Section I.
If the recommended equipment is not available, use
substitute equipment that meets the critical specifica-
tions given in the table.
4-5. PERFORMANCE TEST CARD.
4-6. Performance Test Cards are provided at the end of
this section for your convenience in recording the per-
formance of the 3455A during either test. These cards
can be removed from the manual and used as a perma-
nent record of the incoming inspection or of a routine
performance test. The Test Cards may be reproduced
without written permission from Hewlett-Packard.
4-7, CALIBRATION CYCLE.
4-8. The 3455A requires periodic verification of perfor-
mance. The performance should be tested as part of the
incoming inspection and at 90-day or 6-month intervals,
depending on the environmental conditions and your
specific accuracy requirements. Two tests (performance
and opertional verification) are provided in this section.
The operational verification test should be performed as
an incoming inspection of the instrument. The complete
performance test can be used at the 90-day or 6-month
intervals, and following a complete calibration of the in-
strument. '
4-9. INPUT TERMINALS/CONTROL SETTINGS.
410. Unless otherwise specified, the test signals for the
performance tests can be applied to either the front or
rear INPUT terminals. All tests must be performed in
the INTERNAL Trigger Mode with AUTO CAL on and
MATH off. For standard instruments (rms converter)
the rear panel AC - AC/DC switch must be in the ac
position. Other control settings are included in the test
procedures.
4-11. PERFORMANCE TEST FAILURE.
4-12. If the 3455A fails any of the performance tests or
operational verification test, perform the adjustments
outlined in Section V. If the problem cannot be cor-
rected by the adjustment, refer to Section VIII for
troubleshooting information.
4-13. SPECIFICATION BREAKDOWN.
4-14, The dc, ac and ohms accuracy specifications
(Table 1-1) are grouped according to the selected instru-
ment function, i.e., High Resolution On or Off, ACV
or Fast ACV and 2-Wire or 4-Wire ohms. Within each
group there are three sets of specifications:
a. 24 hour (23°C + 1°C)
b. 90 day (23°C + 5°C)
c. 6 months (23°C + 5°C)
415. The time period over which a set of specifications
applies is relative to the time the instrument is initially
adjusted at the factory or is properly readjusted accor-
ding to the procedures outlined in Section V. Before
proceeding with the dc, ac and ohms accuracy tests, it
will be necessary to determine which set of specifica-
tions applies to your instrument. If the instrument has
just been received and is to be tested as part of the in-.
coming inspection, test for the 90-day specifications. If
the instrument has been readjusted within a period of 24
hours, test for the 24-hour specifications. Test limits for
the 24-hour and 90-day specifications are included in the
tables for the accuracy tests. Test limits for the 6-month
specifications must be derived from the specifications
listed in Table 1-1. If the instrument is operated outside
for the temperature range for a given set of specifica-
tions, the appropriate temperature coefficients, listed in
Table 1-1, must be added to those specifications. The
test limits given in the tables for the dc, ac and ohms ac-
curacy tests do not include temperature coefficients.
4-16. Each set of specifications includes an accuracy
specification for each voltage or ohms range. Accuracy
is specified as a percentage of reading plus an add-on of
one or more digits (counts). For example, the 24-hour
DC Accuracy specification for the 1-volt range (High
Resolution Off) is:
+ (0.003% of reading + 1 digits)
At full scale (1 V) the least significant display digit,
equal to 10 microvolt, is 0.001% of reading. The full-
scale accuracy is therefore:
al