Inverter-Driven 400V Class Motor - Mitsubishi Electric FR-E700 Series Instruction Manual

Wiring
3.8.4

Inverter-driven 400V class motor

In the PWM type inverter, a surge voltage attributable to wiring constants is generated at the motor
terminals. Especially for a 400V class motor, the surge voltage may deteriorate the insulation. When
the 400V class motor is driven by the inverter, consider the following measures:
● Rectifying the motor insulation and limiting the PWM carrier frequency according to the wiring
length. For the 400V class motor, use an insulation-enhanced motor.
– Specify the "400V class inverter-driven insulation-enhanced motor".
– For the dedicated motor such as the constant-torque motor and low-vibration motor, use the
"inverter-driven, dedicated motor".
– Set Pr. 72 "PWM frequency selection" as indicated below according to the wiring length.
Parameter 72
Tab. 3-24: Setting of Pr. 72 according to the wiring length
● Limiting the voltage rise speed of the frequency inverter output voltage (dV/dT):
If the motor requires a rise speed of 500V/μs or less you must install a filter in the output of the
inverter. Please contact your Mitsubishi dealer for more details.
NOTE For details of Pr. 72 "PWM frequency selection", refer to section 6.15.
FR-E700SC EC
Wiring Length
≤ 50m
≤ 15 (14.5kHz)
Electromagnetic compatibility (EMC)
50m to 100m
≤ 8 (8kHz)
≥ 100m
≤ 2 (2kHz)
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