E l e c t r o n i c T e m p e r a t u r e M o n i t o r
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Calibrate
Calibrate
Calibrate
Calibrate
There may be occasions when it is desired to check or change the calibration of
the CT input to the 111W.
Calibrate CT –
The calibrate screen contains help messages which lead one thru
the calibration process:
1. The present CT reading is displayed as % of Full Scale. This can be
compared to the actual value of current thru the CT to determine if
calibration is required. If calibration is required press the Start Calibration
button
2. Set the current thru the CT to zero and press the CT current is ZERO button.
3. Set the current thru the CT to a known value, enter the value as % of Full
Scale and press the Send Calibration Data to ETM button. It is
recommended that the known value be 100% of the full scale of the
instrumentation CT secondary being passed through the provided clamp on
CT (Note: The CT is ordered separately).
NOTE:
The maximum value of the CT current as a percentage is 100%. It is
necessary that the full scale value corresponding to this 100% takes into
account overload conditions of the transformer. For example: A 5 amp
clamp on CT should only be used with a 5 amp transformer
instrumentation CT, if the maximum current of the transformer, even
during overload, corresponds to 5 amps or less on the instrumentation
CT. Any current greater than this 100% value will be considered a
failed sensor.