Answer / chitturi bhaskara rao

1.First measure 4-20mA in field side if cannot get 4-20
then check AO card , if u got 4-20 in field side then check
positioner ,
2. make sure thatt sufficent air supply i,e 3 to 4 bar at
inlet of positinoer.
3.If all correct still valve nvr moves then remove
positionner from the valve and supply the air directly to
actuator ( to 4 bar max) then valve moves smoothly then
check angle of postioner while ur fixing positoner on
control valve .
4 if valve nvr moves smoothly means in side valve jam need
to send over haul

Answer / maneesh

after doing all the priliminary inspection if u found the
valve is struck, u can directly give the air supply to the
actuator not:direct applying og air supply may diamage the
valve it should be done with sufficiant care.if the struck
is minor by repeaded giving of supply air will slowly
remove the struck.agfer this still its struck u can remove
the valve from the praocess line and chel the valve body
whether any solid material bloks the way.if that u can
clean and fix it back

Answer / b.kumaran

after doing all the priliminary inspection if u found the
valve is struck, u can directly give the air supply to the
actuator in a repeated manner.if the struck
is minor by repeaded giving of supply air will slowly
remove the struck.still its struck then loosen the body
bolts and try to open by the above method. If still there is
a struck up then u can remove the valve from the process
line, dismantle and clean the valve body whether any solid
material bloks the way.

Answer / 808

Simulate 4-20mA it with a DMM at control valve. If it works
there, then check wiring.

Answer / aatif alvi

check if the proper volatage i.e 4-20ma is changing the the
operation engineer changes he valve position. if it is
changing the the problems might be with the solonoid..some
times moving the solinoid with screw driver makes it work
again,, as it got stuck due to rusting.

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