Answer Posted / vigneshkumar
Positioner:
A Positioner is like a proportinal Controller.The Set point is the control signal from the primary controller and the controlled variable is the Valve position.
Uses:
1.When the signal Pressure is not enough to operate the control Valve.
2.To make Split range between the valves.
3. It can be used to reverse the action of the actuator from air to open and to air to close & Vice Versa
4.To minimize the effect of Hystersis Effect.
5.To Minimize the Response time for the valve.
6.If the Actuator is spring less Positioner will be used.
7.If the Valve has high friction .
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