Connection Of Stand-Alone Option Units; Magnetic Contactors (Mc) - Mitsubishi Electric FR-E700 Instruction Manual

Wiring
3.8

Connection of stand-alone option units

The inverter accepts a variety of stand-alone option units as required.
CAUTION:
E
Incorrect connection will cause inverter damage or accident. Connect and operate the option
unit carefully in accordance with the corresponding option unit manual.
3.8.1

Magnetic contactors (MC)

Inverter input side magnetic contactor (MC)
On the inverter input side, it is recommended to provide an MC for the following purposes.
● To release the inverter from the power supply when the fault occurs or when the drive is not
functioning (e.g. emergency stop operation). For example, MC avoids overheat or burnout of the
brake resistor when heat capacity of the resistor is insufficient or brake regenerative transistor is
damaged with short while connecting an optional brake resistor.
● To prevent any accident due to an automatic restart at restoration of power after an inverter stop
made by a power failure.
● To separate the inverter from the power supply to ensure safe maintenance and inspection work.
NOTE Since repeated inrush currents at power on will shorten the life of the converter circuit (switching
life is about 1,000,000 times.), frequent starts and stops of the MC must be avoided. Turn on/off the
inverter start controlling terminals (STF, STR) to run/stop the inverter.
FR-E700 SC EC/ENE
Connection of stand-alone option units
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