ABB IMASI13, Инструкция по эксплуатации

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Field Calibration
function block. It reflects the status of the most recently
issued calibration command.
The status of a channel field calibration is also reported as an
output (N+1) of this function block. This output shows the sta-
tus for the channel referenced in the most recent field calibra-
tion command.
Field Calibration
Field calibration is not necessary in normal situations. It
is possible to perform calibration procedures in the field if
ultra stable, known, precision references are available. Field
calibration data is stored in nonvolatile memory.
Factory calibration data is stored in a unique nonvolatile
memory area. If a field calibration does not provide the desired
results, the factory calibration data can be restored. Do this by
tuning specification S1 of FC 217 to 11.
Signal readings can be compensated by changing the gain or
offset of the point signal. In most cases changing these values
will take the place of a field calibration. Refer to FC 217, speci-
fication S5.
This is an example of a set user gain and offset operation:
In this example the specifications have these functions:
•
S1 selects the field calibration operation (five). The value of
five is the set user gain and offset command.
•
S2 is the block address of the FC 215 which corresponds to
the IMASI13 module.
•
S3 calls up the channel to be tuned (channel one).
Function
FC 217 Specifications
S1 S2 S3 S4 S5 S6 1
Tune channel 1 offset and
gain correction 5 100 1 0 gain
value
offset
value
Tune channel 2 offset and
gain correction 5 100 2 0
NOTE:
1. S7 and S8 are not used.