8.10.2 Electrical faults
Note
If you are operating the motor with a converter, the operating instructions of the converter must
also be observed if electrical faults occur.
Table 8-1 Electrical faults
↓ Motor fails to start
↓ Motor accelerates sluggishly
↓ Rumbling noise during startup
↓ Rumbling noise during operation
↓ High temperature rise during no-load operation
↓ High temperature rise with load
↓ High temperature rise of individual winding sections
Possible causes of faults Remedial measures
X X X X Overload Reduce the load.
X Interrupted phase in the supply cable Check the switches and cables.
X X X X Interrupted phase in the feeder cable af‐
ter switching on
Check the switches and cables.
X Mains voltage too low, frequency too high Check the power supply conditions.
X Mains voltage too high, frequency too low Check the power supply conditions.
X X X X X Stator winding incorrectly connected Check the winding connection in the terminal box.
X X X X Winding short circuit or phase short cir‐
cuit in stator winding
Determine the winding resistances and insulation
resistances. Carry out repair work after consulta‐
tion with the manufacturer.
X Incorrect direction of rotation Check the connection.
Operation
8.10 faults
SIMOTICS TN Series N-compact 1LA8
102 Operating Instructions 08/2017