Mitsubishi Electric FR-D720S SC EC, Инструкция по эксплуатации

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Electromagnetic compatibility (EMC) Wiring
3 - 52
3.7.4 Inverter-driven 400V class motor
In the PWM type inverter, a surge voltage attributable to wiring constants is generated at the mo-
tor terminals. Especially for a 400V class motor, the surge voltage may deteriorate the insula-
tion. 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.
●
Limiting the voltage rise speed of the frequency inverter output voltage (dU/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.
Wiring Length
≤
50m 50m to 100m
≥
100m
Parameter 72
≤
15 (14.5kHz)
≤
8 (8kHz)
≤
2 (2kHz)
Tab. 3-25: Setting of Pr. 72 according to the wiring length
NOTE For details of Pr. 72 "PWM frequency selection", refer to section 6.14.