Connection Of The Brake Unit (Fr-Bu) - Mitsubishi Electric FR-A800 Instruction Manual

2.10.2

Connection of the brake unit (FR-BU)

Connect the brake unit (FR-BU(H)) as shown below to improve the braking capability during deceleration.
The FR-BU is compatible with the FR-A846-01800(55K) or lower.
Three-phase AC
power supply



NOTE
• If the transistors in the brake unit should becomes faulty, the resistor will overheat. Install a magnetic 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.
MC
MCCB
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.)
Install a stepdown transformer.
The wiring distance between the inverter and brake unit (FR-BU), and between the brake unit (FR-BU)
and resistor unit (FR-BR) must be within 5 m. Even when the cable is twisted, the wiring length must be
within 10 m.
Connection of stand-alone option units
∗2
T
MC
Motor
R/L1 U
S/L2 V
M
T/L3 W
Inverter
P/+
∗1
N/-
∗3
10m or less
INSTALLATION AND WIRING
ON OFF
MC
FR-BR
TH1
P
PR
TH2
FR-BU
PR
HA
P/+
HB
N/- HC
2
61