Fluke 5790B, Руководство по обслуживанию

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Calibration Adjustment and Verification
Introduction
3
3-3
Automating Calibration Adjustment and Verification
Fluke Calibration uses an automated calibration adjustment and calibration
verification system to accomplish the procedures described here. To minimize
time spent on repetitive measurements and calculations, you can automate the
following procedures to the greatest extent possible. Chapters 5 and 6 of the
User document the remote interfaces and commands that can help you with the
calibration.
Note
A technical paper describes the system in use at Fluke Calibration to
calibrate and verify the 5790A: Calibration and Traceability of a Fully
Automatic AC Measurement Standard, by David Deaver, presented
in the NCSL Workshop and Symposium, 1991. Reprints are
available from Fluke Calibration.The 5790B automated calibration
system is based on the 5790A technical paper.
How Calibration Memory is Organized
Three sets of calibration constants are maintained in memory. Associated with
each set of constants is the date and ambient temperature of the calibration.
Figure 3-1 shows the three sets of calibration constants and how they are purged
following a calibration store operation. The three sets of constants are described
below, from newest to oldest:
1. The “active” set. This is a volatile memory that normally contains a copy
of the contents of the stored set of calibration constants. The only time it
contains different data is after you perform calibration of one or more
ranges, but before you store the updated constants. After calibration, you
must either store or discard the updated constants before you resume
normal operation.
2. The “stored” set. At each power up, the contents of this nonvolatile
memory is copied into the active set memory. Therefore, the stored set is
identical to the active set until you perform a new calibration.
3. The “old” set. Although it is no longer in use, the previous set of
calibration constants is saved in nonvolatile memory. This set is kept in
order to make comparisons in Cal Shift reports.