Mitsubishi Electric FR-A800, Instruction Manual

Page: 116 / 1042

Connection of stand-alone option units Installation and wiring
2 - 86
2.10.4 Connection of the brake unit (BU type)
Connect the brake unit (BU type) correctly as shown below. Incorrect connection will damage the in-
verter. Remove the jumpers across terminals HB and PC and terminals TB and HC of the brake unit and
fit one across terminals PC and TB.
The BU type is compatible with FR-A820-03160(55K) or lower and FR-A840-01800(55K) and lower.
When the power supply is 400 V class, install a stepdown transformer.
For the FR-A820-00490(7.5K) or lower and FR-A840-00250(7.5K) or lower, be sure to remove the
jumper across terminals PR and PX.
I002411E
Fig. 2-63: Connection with the brake unit BU
NOTES The wiring distance between the inverter and brake unit (BU type), and between the brake unit
(BU type) and discharging resistor must be within 2 m each. Even when the cable is twisted, the
wiring length must be within 5 m.
If the transistors in the brake unit should becomes faulty, the resistor will overheat and result in a
fire. Install a magnetic contactor on the inverter's input side and configure a circuit that shut off
the current in case of a fault.
Remove the jumper across terminals P/+ and P1 only when connecting a DC reactor (FR-HEL).
U
V
W
M
R/L1
S/L2
T/L3
N/-
P/+
MCCB MC
P
PR
OCR
N
HC
HB
HA
TB
OCR
PC
MC
MC
T
PR
PX
*2
Three-
phase AC
power
supply
Brake unit
(BU type) Remove the
jumper
Fit a jumper
Motor
Inverter
ON OFF
Discharging
resistor