Emerson Vilter VSS Installation, Operation & Maintenance Manual page 147

Section 6 • Troubleshooting
Table 6-1. Slide Valve Actuator Troubleshooting Guide (3 of 3)
Problem
The motor will not move in either
direction
The motor operates intermittently, several
minutes on, several minutes off.
The motor runs sporadically
The motor runs but output shaft will not
turn.
VSS/VSM/VSH/VSSH • Installation, Operation and Maintenance Manual • Emerson • 35391SD
Reason
The thermal switch has
tripped because
the motor is overheated
Any of the reasons listed in
"The motor operates in one
direction only"
The command shaft is
jammed.
Broken gears in the
gear-motor.
Blown relays or fuses.
Motor is overheating and the
thermal switch is tripping.
Bad thermal switch.
Any of the reasons listed in
"The motor operates in one
direction only"
Stripped gears inside the
gear rotor, or the armature
has come unpressed from the
armature shaft.
Solution
The motor will resume opera-
tion when it cools. This could
be caused by a malfunction-
ing control panel. Consult the
factory.
See above.
Free the command shaft.
Replace the actuator.
Check and replace blown relays
and/or fuse
This could be caused by a
malfunctioning control panel.
Consult the factory.
Replace the actuator.
See above.
Replace the actuator.
6 – 3