TrouBlE shooTIng
29
Electrical Failures
Failure
Possible cause of failure
Corrective action
Motor does not start, no current,
no noise.
Interruption on at least two phases.
(Open circuit)
Measure the resistance between the phases to
investigate if the stator is damaged. If the stator is
damaged, please contact ABB for further
instructions.
Motor starts with a continuous
hum.
Interruption on one phase. (Open
circuit)
Check the incoming cables. Measure the resistance
for each phase. If the stator is damaged, please
contact ABB for further instructions.
Motor starts with the wrong
direction of rotation.
Wrong phase sequence on the
incoming cables.
Check the phase sequence for the incoming cables.
Motor generates an abnormally
high noise level.
Can be caused by mechanical or
electrical interference.
Switch off the electrical feed. If the noise remains,
it is a mechanical fault. If not, it is an electrical
fault.
Motor current is abnormally high.
Fault in the stator winding.
Measure the winding resistance between the
stator terminals.
Motor has different phase
currents and gets high
temperatures.
Asymmetrical feeding.
Check the similarity of the phase voltage on the
incoming cables.
Motor gets an abnormally high
phase current and high
temperature, also at no load.
Wrong incoming voltage level.
Correct the incoming voltage levels.
Smoke appears from the motor.
Fire after flash-over or short circuit
in a part of the stator winding.
Disconnect the motor, remove it. Rewinding is
most likely necessary, please contact ABB for
further instructions.
Motor current is abnormally high.
Demagnetized rotor magnets.
It’s possible to continue the operation with
reduced performance. The rotor should be
replaced to obtain full performance, please contact
ABB for further instructions.
Insulation resistance below 10 M.
The stator winding is too damp.
Check for any defect components (covers, seal
etc.). The stator winding must be oven dried,
please contact ABB for further instructions.
Table 8.
Electrical failures.
