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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