Connection Of The Brake Unit (Fr-Bu2) - Mitsubishi Electric FR-A820-00046 (0.4K) Instruction Manual

2.10.2 Connection of the brake unit (FR-BU2)

Connect the brake unit (FR-BU2(H)) as follows to improve the braking capability during deceleration.
 Connection example with the GRZG type discharging resistor
Three-phase AC
power supply
*1 When wiring, make sure to match the terminal symbols (P/+, N/-) on the inverter and on the brake unit (FR-BU2). (Incorrect connection will
damage the inverter and brake unit.)
*2 When the power supply is 400 V class, install a stepdown transformer.
*3 Be sure to remove the jumper across terminals PR and PX when using the FR-BU2 with the inverter of FR-A820-00490(7.5K) or lower, or FR-
A840-00250(7.5K) or lower.
*4 The wiring distance between the inverter, brake unit (FR-BU2) and discharging resistor must be within 5 m. Even when the cable is twisted, the
wiring length must be within 10 m.
*5 It is recommended to install an external thermal relay to prevent overheat of the discharging resistor.
*6 For the connection method of the discharging resistor, refer to the Instruction Manual of the FR-BU2.
• Recommended external thermal relay
Brake unit
FR-BU2-1.5K
FR-BU2-3.7K
FR-BU2-7.5K
FR-BU2-15K
FR-BU2-H7.5K
FR-BU2-H15K
FR-BU2-H30K
NOTE
• Set "1" in Pr.0 Brake mode selection in the FR-BU2 to use a GRZG type discharging resistor.
• Do not remove the jumper across terminals P/+ and P1 except when connecting a DC reactor (FR-HEL).
100
2. INSTALLATION AND WIRING
2.10 Connection of stand-alone option units
MCCB
MC
∗3
Discharging resistor
GZG 300W-50Ω (one)
GRZG 200-10Ω (three in series)
GRZG 300-5Ω (four in series)
GRZG 400-2Ω (six in series)
GRZG 200-10Ω (six in series)
GRZG 300-5Ω (eight in series)
GRZG 400-2Ω (twelve in series)
T ∗2
MC
OCR
Motor
R/L1 U
External thermal
relay
S/L2 V
M
W
T/L3
FR-BU2
Inverter
∗4
PR
PR
P/+
P/+
∗1
PX
N/-
N/-
BUE
SD
∗4
10 m or less
Recommended external
thermal relay
TH-N20CXHZ 1.3A
TH-N20CXHZ 3.6A
TH-N20CXHZ 6.6A
TH-N20CXHZ 11A
TH-N20CXHZ 3.6A
TH-N20CXHZ 6.6A
TH-N20CXHZ 11A
OCR
contact
ON OFF
MC
GRZG type
∗6
discharging
resistor
R R
∗5
A
B
∗1
C
1/L 5/L
1 3
TH-N20
2/T 6/T
1
To a resistor
To the brake
unit terminal P/+
3