Mitsubishi Electric fr-e700 series, Instruction Manual

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Main circuit connection Wiring
3 - 14
When driving a 400 V class motor by the inverter, surge voltages attributable to the wiring constants
may occur at the motor terminals, deteriorating the insulation of the motor. Take the following meas-
ures
햲
or
햳
in this case.
햲
Use a "400 V class inverter-driven insulation-enhanced motor" and set frequency in Pr. 72 “PWM
frequency selection” according to wiring length.
햳
Connect the surge voltage suppression filter (FFR-DT) on the inverter output side.
Wiring Length
50 m 50 m to 100 m 100 m
Carrier frequency 14.5 kHz 8 kHz 2 kHz
NOTES Note that the motor windings are subjected to significantly higher loads when the motor is oper-
ated by inverter than with normal mains operation. The motors must be approved for inverter
operation by the manufacturer (refer also to section 3.9.4).
Especially for long-distance wiring, the inverter may be affected by a charging current caused by
the stray capacitances of the wiring, leading to a malfunction of the overcurrent protective func-
tion, fast response current limit function, or stall prevention function or a malfunction or fault of
the equipment connected on the inverter output side.
If fast-response current limit malfunctions, disable this function. When the stall prevention func-
tion misoperates, increase the stall level. (Refer to Pr. 22 "Stall prevention operation level" and
Pr. 156 "Stall prevention operation selection".)
Refer to section 6.15.1 for details of Pr. 72 "PWM frequency selection". Refer to the manual of the
option for details of surge voltage suppression filter (FFR-DT).
When using the automatic restart after instantaneous power failure function with wiring length
exceeding than 100 m, select without frequency search (Pr. 162 = "1, 11").