Chapter 1 Safety Precautions GK600E User Manual
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1.2.5 Insulation of the Motor
In view of the fact that the drive output is PWM high frequency chopping voltage accompanied
by higher harmonics, the noise, temperature rise and vibration of the motor is higher compared
w ith sinusoidal voltage. Particularly this debases motor insulation. Therefore, the motor should
be subjected to insulation inspection before initial use or reuse after being stored for a long
period of time. The motor in regular service should also be subjected to regular insulation
inspection so as to avoid damage to the drive as a result of motor insulation damage. A 500V
voltage mode mega-ohmmeter is recommended to use for the measurement of the motor
insulation, during w hich, it is essential to disconnect the motor from the drive. Normally, the
insulation resistance of
the motor should be bigger than 5MΩ.
1.2.6 Derating
Due to the thin air in high-altitude areas, the radiating performance of the drive w ith forced air
cooling may degrade w hile the electrolyte of electrolytic capacitors is more volatile, w hich can
result in reduction in product life. Drive should be derated w hen used in an area at the altitude
above 1000 meters. It is recommended to derate 1% for every 100m w hen the altitude is above
1000 meters.
