Emerson VSR, VSM, VSS Slide Valve Actuator Trouble Shooting Guide, Problem, Reason, Solution

Slide Valve Actuator Trouble Shooting Guide

Problem Reason Solution

The actuator cannot be cali- brated

The actuator goes into cali- bration mode spontane- ously

The actuator goes into cali- bration mode every time power is restored after a power loss

Dirt or debris is blocking one or both optocoupler slots

The photochopper fence extends less than about half way into the optocoupler slots

The white calibrate wire in the grey Turck cable is grounded

Dirt and/or condensation on the position sensor boards are causing it to malfunction

The calibrate button is stuck down

The position sensor has failed

Push button is being held down for more that ¾ second when going through the calibration procedure

The white calibrate wire in the grey Turck cable is grounding intermit- tently

A very strong source of electromag- netic interference (EMI), such as a contactor, is in the vicinity of the actuator or grey cable

There is an intermittent failure of the position sensor

The motor brake is not work- ing properly (see theory section above.)

Clean the optocoupler slots with a Q-Tip and rubbing alco- hol.

Adjust the photochopper so that the fence extends further into the optocoupler slots. Make sure the motor brake operates freely and the pho- tochopper will not contact the optocouplers when the shaft is pressed down.

Tape the end of the white wire in the panel and make sure that it cannot touch metal

Clean the boards with an elec- tronics cleaner or compressed air.

Try to free the stuck button.

Replace the actuator.

Depress the button quickly and then let go. Each ¾ second the button is held down counts as another press.

Tape the end of the white wire in the panel and make sure that it cannot touch metal.

Increase the distance between the EMI source and the actua- tor.

Install additional metal shield- ing material between the EMI source and the actuator or cable.

Replace the actuator.

Get the motor brake to where it operates freely and recalibrate.

Replace the actuator.

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