Teco Installation and Maintenance Manual
TEFC Squirrel Cage Induction Motors
Teco Electric and Machinery Company
Manual Number: IOM ~ TEFC Rev.01
29
i.
Ambient conditions.
ii.
Start and stop frequency.
iii.
Trouble with components affecting motor functions.
iv.
Parts which wear (eg. bearings).
v.
The important position of a motor in operation of a factory, mine etc.
should be fully recognised. Therefore, its condition should be monitored,
especially when it is operating in severe conditions.
6.1.2. Motor Windings.
a.
For measurement of insulation resistance and tests to determine quality of
insulation resistance, please refer to measures stated in Section 4.1.2.
b.
Inspection of coil end:
i.
Grease and dust accumulated on coil may cause insulation
deterioration and a reduction in cooling efficiency.
ii.
Moisture.
iii.
Discolouring from original colour. Overheating mainly causes this.
c.
Stator wedges, is there any change from their original position?
d.
Is the tie wire at the coil ends in correct position with no movement?
6.1.3. Bearings.
a.
Please refer to section 7 for bearing maintenance.
6.1.4. Cleaning the interior of the motor.
a.
After a motor has been in operation for some time, accumulation of dust,
carbon powder and grease etc., on the inside is unavoidable, and may
cause damage. The inside should therefore, be regularly cleaned and
examined to assure reliable performance.
b.
Points to note during cleaning:
i. If using compressed air or a blower (Typically for squirrel cage only).
Compressed air should be free of moisture.
Maintain air pressure at 4kg/cm
2
, since high pressure can cause
damage to coils.
