
SAFETY PRECAUTIONS B-65382EN/02
s-8
NOTE
- Do not apply a commercial power source voltage directly to a motor.
Applying a commercial power source voltage directly to a motor may
result in its windings being burned. Be sure to use a specified
amplifier for supplying voltage to the motor.
- Before using a motor, measure its winding and insulation resistances, and make
sure they are normal.
Especially for a motor that has been stored for a prolonged period of
time, conduct these checks. A motor may deteriorate depending on the
condition under which it is stored or the time during which it is stored.
For the winding resistances of motors, refer to their respective
specification manuals. For insulation resistances, see the following
table.
- To use a motor as long as possible, perform periodic maintenance and inspection
for it, and check its winding and insulation resistances.
Note that extremely severe inspections (such as dielectric strength
tests) of a motor may damage its windings.
- Motor insulation resistance measurement
Measure an insulation resistance between each winding and motor
frame using an insulation resistance meter (500 VDC). Judge the
measurements according to the following table.
Insulation resistance Judgment
100 MΩ or higher Acceptable
10 to 100 MΩ
The winding has begun deteriorating. There is no
problem with the performance at present. Be
sure to perform periodic inspection.
1 to 10 MΩ
The winding has considerably deteriorated.
Special care is in need. Be sure to perform
periodic inspection.
Lower than 1 MΩ Unacceptable. Replace the motor.