Omron SYSDRIVE 3G3MV SERIES User Manual page 340

Chapter 11
Using the Inverter for a Motor
H Motor Burnout Caused by Insufficient Dielectric Strength of Each
Phase of Motor
Surge occurs among the phases of the motor when the output voltage is switched.
If the dielectric strength of each phase of the motor is insufficient, the motor may burn out.
The dielectric strength of each phase of the motor must be higher than the maximum surge voltage.
Normally, the maximum surge voltage is approximately three times the power voltage imposed on the
Inverter.
Be sure to connect Inverter-dedicated motors if the Inverter is a 400-V-class model. Standard motors do
not have sufficient dielectric strength and may burn out.
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