Thermo AC-4000, Operating And Service Manual

Page: 227 / 242

61
Motor runs too fast.
Motor will not reach the
desired speed.
Motor pulsates or surges
under load.
1. MAX SPD and MIN
SPD are set too high.
2. Motor field connections
are loose (shunt wound
motors only).
1. MAX SPD setting is
too low.
2. IR COMP setting is too
low.
3. TORQUE setting is too
low.
4. Motor is overloaded.
1. IR COMP is set too
high.
2. Motor bouncing in and
out of current limit.
1. Calibrate MAX SPD
and MIN SPD. See
page 42.
2. Check motor field
connections.
1. Increase MAX SPD
setting. See page 42.
2. Increase IR COMP
setting. See page 44.
3. Increase TORQUE
setting. See page 43.
4. Check motor load.
Resize the motor and
drive if necessary.
1. Adjust the IR COMP
setting slightly CCW
until the motor speed
stabilizes. See page
44.
2. Make sure motor is not
undersized for load;
adjust TORQUE
trimpot CW. See page
43.
Problem Possible
Causes
Suggested
Solutions
Troubleshooting