Mitsubishi Electric FR-F740 EC Instruction Manual page 527

Parameter
When the motor is operated at 50Hz, more efficient operation can be performed by the com-
mercial power supply than by the inverter. When the motor cannot be stopped for a long time for
the maintenance/inspection of the inverter, it is recommended to provide the commercial power
supply circuit.
To switch between inverter operation and commercial power supply operation, an interlock must
be provided to stop the motor once and then start it by the inverter in order to prevent the inverter
from resulting in an overcurrent alarm. Using the commercial power supply switchover se-
quence function that outputs the timing signal for operation of the magnetic contactor, a com-
plicated commercial power supply switchover interlock can be provided by the inverter.
FR-F700 EC
Special operation
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