Braking Resistors; Selecting Braking Resistors - INVT Goodrive20-EU Series Operation Manual

Goodrive20-EU Series VFD
C.7 Braking resistors
C.7.1 Selecting braking resistors
It is appropriate to use braking resistor or braking unit when the motor brakes sharply or the
motor is driven by a high inertia load. The motor will become a generator if its actual rotating
speed is higher than the corresponding speed of the reference frequency. As a result, the
inertial energy of the motor and load return to the VFD to charge the capacitors in the main DC
circuit. When the voltage increases to the limit, damage may occur to the VFD. It is necessary
to apply braking unit/resistor to avoid this accident happens.
 Only qualified electricians are allowed to design, install, commission and
operate on the VFD.
 Follow the instructions in "warning" during working. Physical injury or
death or serious property may occur.
 Only qualified electricians are allowed to wire. Damage to the VFD or
brake options and part may occur. Read carefully the instructions of
braking resistors or units before connecting them to the VFD.
 Do not connect the braking resistor to other terminals except for PB and
(-). Do not connect the braking unit to other terminals except for (+) and (-).
Damage to the VFD or braking circuit or fire may occur.
 Connect the braking resistor or braking unit to the VFD according to the
diagram. Incorrect wiring may cause damage to the VFD or other devices.
Goodrive20-EU series VFDs have internal braking units.
Model
GD20-0R4G-S2-EU
GD20-0R7G-S2-EU
GD20-1R5G-S2-EU
GD20-2R2G-S2-EU
GD20-0R4G-2-EU
GD20-0R7G-2-EU
GD20-1R5G-2-EU
GD20-2R2G-2-EU
GD20-004G-2-EU
GD20-5R5G-2-EU
GD20-7R5G-2-EU
GD20-0R7G-4-EU
Braking
Type of resistor at
braking 100% of
unit braking
torque (Ω)
361
192
96
65
361
Built-in 192
braking unit
96
65
36
26
19
653
Optional peripheral accessories
Consumed power of the braking
resistor (kW)
10%
braking braking
0.06
0.11
0.23
0.33
0.06
0.11
0.23
0.33
0.6
0.75
1.13
0.11
-162-
50% 80%
braking
0.30 0.48
0.56 0.90
1.10 1.80
1.70 2.64
0.3 0.48
0.56 0.9
1.1 1.8
1.7 2.64
3 4.8
4.13 6.6
5.63 9
0.56 0.90
Min.
braking
resistor
(Ω)
42
42
30
21
131
93
44
44
33
25
13
240