Mitsubishi Electric FR-A700 Manual page 78

Name (type)
Brake unit
BU-(H)
Electrical-discharge
resistor
GZG type
GRZG type
81
A brake unit is an option that fully enhances the regenerative braking capability of the inverter, and should be used with an electrical-
discharge resistor.
Brake units should be selected according to the required braking torque.
Brake unit selection table
Motor(kW) 0.4
Voltage 1.5
0.75
Braking torque
50% 30s BU-1500
200V
output
100% 30s BU-1500 BU-3700
50% 30s *
400V
output
100% 30s *
* The inverter of 1.5K or less with 400V output can not be used in combination with a brake unit.
To use in combination with a brake unit, use the inverter of 2.2K or more.
Combination of brake unit and electrical discharge resistor
Voltage Brake Unit Resistor Type
BU-1500 GZG300W-50Ω (one)
GRZG200-10Ω
BU-3700
(three in series)
GRZG300-5Ω
BU-7.5K
(four in series)
GRZG400-2Ω
BU-15K
(six in series)
Brake unit
W
Type
BU-1500,3700,7.5K,15K
BU-H7.5K,H15K,H30K
(Note) 1.Connect so that the terminal symbols of the inverter and brake unit match with each other. Incorrect connection will damage the inverter.
2.Minimize the cable length between the inverter and brake unit and the electrical-discharge resistor and brake unit. Use a twisted cable when the
wiring length exceeds 2m.
(If twisted cables are used, the wiring length should be within 5m.)
Handling precautions
1. The thermal relay in the brake unit will trip if the rated torque is continuously output. After a trip, reset the inverter and increase its deceleration time
setting.
2. The maximum temperature rise of the electrical-discharge resistor is 100°C. Use heat-resistant wires and wire to avoid contact with resistors.
Specifications, Structure, etc.
2.2 3.7 5.5 7.5 11
BU-3700 BU-7.5K BU-15K
BU-7.5K BU-15K 2×BU-15K
BU-H7.5K BU-H15K
BU-H7.5K BU-H15K BU-H30K
Used Cable
Voltage Brake Unit
(P, N)
2
2mm
2
2mm
2
3.5mm
2
3.5mm
Electrical-discharge resistor
D
(Unit: mm)
W D H
100 128 240
160 145 240
15 18.5 22 30 37
2×BU-15K 3× BU-15K
4× 5×
3×BU-15K
BU-15K BU-15K
BU-H30K 2×BU-H30K
2×BU-H30K 3×BU-H30K
Resistor Type
GRZG200-10Ω
BU-H7.5K
(six in series)
GRZG300-5Ω
BU-H15K
(eight in series)
GRZG400-10Ω
BU-H30K
(twelve in series)
W D
(Unit: mm)
Type W D
GZG300W
335 40 78
GRZG200 306 26 55
GRZG300 334 40 79
GRZG400
411 40 79
45 55
4×
BU-15K
6× 7×
BU-15K BU-15K
4×
BU-
H30K
Used Cable
(P, N)
2
2mm
2
3.5mm
2
3.5mm
H