Connection of stand-alone option units
Connection of the brake unit (FR-BU)
Connect the brake unit (FR-BU2(H)) as shown below to improve the braking capability during decel-
The FR-BU is compatible with FR-F820-02330(55K) or lower and FR-F840-01160(55K) and lower.
When wiring, make sure to match the terminal symbol (P/+, N/-) at the inverter side and at the
brake unit (FR-BU(H)) side. (Incorrect connection will damage the inverter.)
When the power supply is 400 V class, install a stepdown transformer.
The wiring distance between the inverter and brake unit (FR-BU2), and between the brake unit
(FR-BU) and discharging resistor unit (FR-BR) must be within 5 m each. Even when the cable is
twisted, the wiring length must be within 10 m.
If the transistors in the brake unit should becomes faulty, the resistor will overheat. Install a mag-
netic contactor on the inverter's input side and configure a circuit that shut off the current in case
of a fault.
Do not remove the jumper across terminals P/+ and P1 except when connecting a DC reactor
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Connection with the brake unit FR-BU
≤ 10 m
Installation and wiring