SMAR FI302, Operation, Maintenance & Instruction Manual

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FI302 - Operation and Maintenance Instruction Manual
3.2
Current Trim
The FI302 provides the capability of making a trim in the output channels, if necessary.
A trim is necessary if the indicator reading of the transducer block output differs from the actual
physical output. The reason may be:
•
The user's current meter differs from the factory standard.
•
The converter had its original characterization shifted by over-load or by long term drift.
The user can check the calibration of the transducer output by measuring the actual current in the
output and compare it with the device’s indication (of course an appropriate meter should be used).
If a mismatch is detected, a trim can be done.
Trim can be done in two points:
LOWER TRIM: Is used to trim the output at the lower range.
UPPER TRIM: Is used to trim the output at the upper range.
These two points define the linear characteristic of the output. Trim in one point is independent from
the other.
There are two ways of doing the trim: using local adjustment or using SYSCON (the System
Configurator from SMAR ). When doing the trim, make sure you are using an appropriate meter (with
the necessary accuracy).
Via SYSCON
Configure in the Transducer, the parameter “TERMINAL_NUMBER” with 1,2, or 3, according to the
“CHANNEL” number of Analog Output block.
Figure 3.1 - Choosing the Output Channel – FI302
In this case the
channel 1 was
choosen. This parameter
selects the terminal
number which the
output current will be
generated and
calibrated.