Mitsubishi Electric FR-E520 Instruction Manual page 44

(2) Connection of the brake unit (BU)
Connect the BU brake unit correctly as shown below. Incorrect connection will damage
the inverter. Remove the jumper across terminals HB-PC and terminals TB-HC of the
brake unit and fit it to across terminals PC-TB.
NFB
Power
supply
Connect a
jumper.
Note: 1. The wiring distance between the inverter, brake unit and discharge resistor
should be within 2m. If twisted wires are used, the distance should be within
5m.
2. If the transistors in the brake unit should fail, the resistor will be extremely
hot, causing a fire. Therefore, install a magnetic contactor on the inverter's
power supply side to shut off current in case of failure.
3. When the power supply is 400V class, install a step-down transformer.
T (Note 3)
MC
ON
OFF
MC
PC HA HB HC TB
OCR
INSTALLATION AND WIRING
MC Inverter
R (L )
1
S (L )
2
T (L )
3
P (+) N (-)
Discharge resistor
Remove
jumpers.
P
BU type brake unit
34
Motor
U
V IM
W
PR
OCR
N