4.5 Brake Chopper and Brake Resistor
4.5.1 Braking Ratio
Brake resistors with different power ratings are available to dissipate braking en-
ergy when the frequency converter is in generator mode. The following table
lists the details of brake chopper and brake resistor corresponding to each
brake power in the condition that a certain braking ratio is given.
ED Braking ratio
Tb Braking time
Tc Engineering cycle time in application
Fig. 4-2: Braking ratio
4.5.2 Recommended Brake Chopper and Brake Resistor
When braking voltage is 750 V, ED = 10 % and braking torque is 100%, the rec-
ommended brake chopper and brake resistor are listed as below.
Brake pow-
er (KW)
Brake chopper
type code
Number of
brake
choppers
Brake resistence(Ω) Power of brake resis-
tor(KW)
Number of
paralleled
brake re-
sistors
Recom-
mended
value
Min. value
Recom-
mended
value
Min. value
0.4
Internal
-
750
-
0.08
-
1
0.75
Internal
-
750
-
0.08
-
1
1.5
Internal
-
400
-
0.26
-
1
2.2
Internal
-
250
-
0.26
-
1
3.0
Internal
-
150
-
0.39
-
1
4.0
Internal
-
150
-
0.39
-
1
5.5
Internal
-
75
-
0.78
-
1
7.5
Internal
-
75
-
0.78
-
1
11.0
Internal
-
40
-
1.56
-
1
15.0
Internal
-
40
-
1.56
-
1
18.5
Internal
-
32
-
4.80
-
1
22.0
Internal
-
25
-
4.80
-
1
30
FEAE07.1-EA1-
NNNN
1
20
≥8
6.00
≥4
1
37
1
16
≥8
9.60
≥5
1
45
1
13.6
≥8
9.60
≥6
1
55
1
20
≥8
6.00
≥7
2
Brake Chopper
Bosch Rexroth AG
Brake Chopper Overview
DOK-RCON03-EFC*BRAKE**-IT01-EN-P
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