(1) measurement of the stator, winding between each phase and winding to ground insulation resistance.
Insulation resistance R should meet the following formula.
R＞Un/(1000+P/1000)(MΩ)
Un: rated voltage of motor winding (V)
P: motor power (KW)
For the motor with Un = 380V, R＞0.38MΩ.
If the insulation resistance is low, it can be.
a: no-load operation of the electric motor for 2 to 3h drying.
b: using 10% of the rated voltage of low-voltage alternating current into the winding or three phase winding in series with DC baking, keeping the current at 50% of the rated current.
c: use the fan to send in hot air or heating element heating.
(2) Clean the electric motor.
(3) Replace the bearing grease.
Please check from the electric motor manufacturer TELO MOTOR to get more information about electric motor ;