Carrier PC211 Start-Up, Operation And Maintenance Instructions Manual page 308

Table 13 — Cutler-Hammer Solid-State Starter Troubleshooting Guide (Continued)
Problem
Motor accelerates too
quickly.
Current limit adjustment
has no effect during
acceleration.
Starter or motor is noisy
or vibrates when start-
ing.
Mechanical shock to
machine.
End of limit contact
does not close.
Current trip contact
does not close when
current goes above the
trip setting.
Current trip contact
closes when current is
below trip setting.
Motor current, voltage,
and speed oscillate.
Probable Cause
Current limit is too high.
Improper current feedback.
Pulse start setting is too long.
Broken current feedback transformer wire.
Improper current feedback.
Single phasing due to open phase.
Single phasing or unbalanced current due
to non-firing SCR.
Defective motor.
Current increases too quickly.
Starter is in current limit.
Improper current feedback.
Improper current feedback.
Power saver is misadjusted.
Area of Correction
Decrease current limit setting counter-
clockwise.
Check current calibrator for proper resis-
tance value.
Decrease pulse start time counterclock-
wise.
Check for a broken current feedback
transformer wire.
Check current calibrator for proper resis-
tance value.
Check wiring and overload heater coils.
Check gate lead wiring to SCRs.
Check motor for shorts, opens, and
grounds.
Decrease starting current counterclock-
wise. If necessary, increase ramp time
clockwise.
Perform SCR full voltage test.
Check current calibrator for proper resis-
tance value.
Check current calibrator for proper resis-
tance value.
Turn power saver adjustment CCW until
oscillations cease.