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Manual
Signal change has no effect on the actuator position.
– Make sure the supply pressure is switched on.
– Signal wires are wrongly connected.
– The wiring between the terminal block and the printed circuit board on
the force coil is broken. Check resistance.
– Pipe connections between the PMV Positioner and the actuator is wrong.
– A wrong portion of the cam is being used.
With a small change in the control signal the actuator runs to the end po-
sition.
– Pipe connections between the PMV Positioner and the actuator is wrong.
Inaccurate positiomng
– Dirty valve body.
– Dirty restrictor or nozzle.
– Iron dust in the magnet gap.
– Defective diaphragms.
– The sizing of the actuator is incorrect. Output torque of the actuator is too
small or the supply pressure is too low.
– Torque requirement of the valve has increased.
Overshoot or hunting during positioning.
– Internal gain is too high.
– Capacity of the supply pipe is too small or air lter is clogged. In this
event the input pressure to the PMV Positioner drops steeply when
the pilot valve feeds air into the actuator.
Trouble Shooting
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