Answer / imran

check as
1-put the controll valv in manual and check incoming signal
if stable then problem in controll valve
2- check positioner condition its feedback link ,incase of
smart poistener check feedback potentiometer.spring and
configration.
3-check diaphragam
4-gland packing

Answer / bhavesh

check the gland packing,check the positioner o/p is
unstable,check the small leakage on actuator.

Answer / muhammad arsalan afzal

1=First of all check the feedback link of positioner mostly
such type of problem occur due to feedback link looseness.
2=Gain of the controller is too high you have to adjust it.
3=Gland packing is too tight slightly lose the gland pusher's
screws.

Answer / s.k.bakshi

1. First check the positioner air supply and the positioner.
2. If problem persists tune the PID.

Answer / suman chakraborty

check I/P signal means I/P and O/P whether the AFR o/p of I/P is stable or not.and check the AI Chanel of I/P.

Answer / dhaval joshi

First check actuator position..removed power from the
actuator...and accordingly connect first power supply
cable,after connect command and feedback cable.

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