what is the meaning of reverse action and forward action of
control valve...

Answer Posted / alexpandian

Hi,

We r using direct&reverse actuion in many places:

Control vlv- By giving air, if the stem of actuator moves
down then its dircet acting actutor & if stem moves up then
it is reverse acting.

Controller-
DIRECT: If the PV is less than SV then MV will
decrease.Mainly using in vent valve application.
REVERSE; If the PV is less than SV then MV will
increase.using in normal control loops.

PV-process value SV-set value MV-manipulated value

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