what is the meaning of reverse action and forward action of
control valve...
Answer Posted / lenin kumar
HhHHH
Hi my dear friend the valve action depends on the
service.If the PV increasing the valve opening also
increasing, the action is direct action.If the PV
increasing, the valve opening decreasing i.e reverse action.
For example if you used one valve to fill the tank.if the
PV increasing, you have to close the valve.i.e your valve
action is reverse to the PV value.
If you used valve in discharge line of the tank.If the PV
increasing, you have to open the valve. i.e your valve
action is direct to the PV value.
SP-PV=Error=Reverse action
PV-SP=Error=direct action
Is This Answer Correct ? | 33 Yes | 6 No |
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