13
Setting the CPT
Once the POT drive is commissioned for full valve travel, the
CPT can be calibrated to output a 4-20 mA loop powered
signal. This can be used as direct actuator position feedback
to the site control system.
The CPT option includes two different trimming potentiometers
to enable zero and span values to be calibrated.
CAUTION: The actuator position limits and POT drive
must be configured prior to setting the AID CPT.
1) Run the actuator to the Closed position limit using
electrical operation or the handwheel.
2) Connect a powered test meter across the CPT terminals
and measure the transmitted current – refer to actuator
wiring diagram.
3) Rotate the ZERO trimming potentiometer so that 4 mA is
output from the CPT.
4) Run the actuator to the Open position limit using
electrical operation or the handwheel.
5) Rotate the SPAN trimming potentiometer so that 20 mA is
output from the CPT.
6) Adjustment of the SPAN will cause the ZERO to change
a small amount. It is important to repeat steps 1 to 5 a
second time in order to remove this calibration error.
3. Commissioning
A4
US
US
A4
US
A4
US
A4
A4
US
US
A4
US
A4
A4
US
