6 – 2
VSG/VSSG • Installation, Operation and Maintenance Manual •Vilter/Emerson • 35391STG
Section 6 • Troubleshooting
Problem
Reason
Solution
The actuator does not transmit the
correct position after a power loss
The motor was manually moved
while the position sensor was not
powered.
Recalibrate.
The motor brake is not working
properly
Get the motor brake to where it op-
erates freely and then recalibrate.
The position sensor’s EEPROM
memory has failed
Replace the actuator.
There is a rapid clicking noise when
the motor is operating
The photochopper is misaligned
with the slotted optocouplers
Try to realign or replace the actuator.
The photochopper is positioned too
low on the motor shaft.
Adjust the photochopper so that
the fence extends further into the
optocoupler slots.
A motor bearing has failed
Replace the actuator.
The motor operates in one direction
only
There is a loose connection in the
screw terminal blocks
Tighten.
There is a loose or dirty connection
in the yellow Turck cable
Clean and tighten.
The position sensor has failed
Replace the actuator.
There is a broken motor lead or
winding
Replace the actuator.
The motor will not move in either
direction
The thermal switch has tripped be-
cause the motor is overheated
The motor will resume operation
when it cools. This could be caused
by a malfunctioning control panel.
Consult the factory.
Any of the reasons listed in “The mo-
tor operates in one direction only”
See above.
The command shaft is jammed
Free the command shaft.
Broken gears in the gearmotor
Replace the actuator.
Blown relay or fuse.
Check and replace blown relay and/
or fuse.
The motor runs intermittently, sev-
eral minutes on, several minutes off
Motor is overheating and the ther-
mal switch is tripping
This could be caused by a malfunc-
tioning control panel. Consult the
factory.
The motor runs sporadically
Bad thermal switch
Replace the actuator.
Any of the reasons listed in “The mo-
tor will not move in either direction”
See above.
The motor runs but output shaft will
not turn
Stripped gears inside the gear
motor or the armature has come un-
pressed from the armature shaft
Replace the actuator.
Table 6-1. Slide Valve Actuator Troubleshooting Guide (2 of 2)