LEESON NEMA 4X SCR Control: 174107.00 - Manual (Page 44)

38 Troubleshooting SPEEDMASTER™ OPERATION MANUAL
Symptom Possible
Causes
Suggested
Solutions
Motor pulsates or
surges under load
On non-reversing
drives, motor runs in
the opposite
direction
Motor will not stop
when the speed
adjust potentiometer
or reference signal
is set to zero speed.
1. IR COMP is set too
high.
2. Control is in current
limit mode.
1. Motor armature leads
are reversed.
1. MIN SPD trimpot is
not adjusted properly.
1. Adjust the IR COMP
setting slightly CCW
until the motor
speed stabilizes
(page 13).
2. Check that motor is
of sufficient
horsepower and
amperage.
1. Reverse connections
to the motor
armature.
1. Slowly rotate the
MIN SPD trimpot
until the motor
stops.