Beijer Electronics Frequency Inverter BFI-E3
KI00369C 2021-09
www.beijer.se www.beijer.no
www.beijerelectronics.de www.beijerelectronics.com www.beijerelektronik.com.tr
8 (28)
4.6 Brake transistor and external brake resistor
If a larger amount of regenerate power is being produced than the BFI can handle at stop function AC
Flux Braking can be used. Means that motor is being over excitated during stop and used as brake
resistor. Note that heat of motor will increase, and it only works during deceleration. Put parameter P-
05=3 to activate AC Flux braking.
If AC Flux braking is not enough BFI from Size2 has a dynamic brake transistor and an optional
external braking resistor can be connected to +DC and BR when required. The brake resistor circuit
should be protected by a suitable thermal protection circuit. The –DC, +DC and BR connections are
blanked off by plastic tabs when sent from the factory. The plastic tabs can be removed if/when
required.
Table shows models with built-in brake transistor suggestion of brake resistors.
-
Internal resistor, OD-BR100-BFI is mounted inside BFI IP20 and is activated and
protected from overload by setting of P34=1.
-
External resistor must always be used together with a slow external overload
protection and P34=2. Table shows setting current of the external overload
protection.
Drive model
Minimum resistance
when regenerated
power is equal with
BFI power [ohm]
Brakeresistor to be used
Voltage
BFI-E3
Name
Setting
overload
protection
Power resistor [kW]
Resistans
[ohm]
Medel
Peak for
0,125 sec
1-phase
230 VAC
0070[1,5kW]
100
OD-BR100-BFI
P34=1
0,2
12
100
0105[2,2kW]
69
OD-BR100-BFI
P34=1
0,2
12
100
BSD600R75-4
2,8 A
0,6
75
0153[4,0kW]
25
OD-BR100-BFI
P34=1
0,2
12
100
3-phase
400 VAC
0041[1,5kW]
406
OD-BR100-BFI
P34=1
0,2
12
100
2 BSD600R140-4
connected in serial
2,1 A
1,2
-
280
0058[2,2kW]
277
OD-BR100-BFI
P34=1
0,2
12
100
2 BSD600R82-4
connected in seriell
2,7 A
1,2
-
164
0095[4,0kW]
152
OD-BR100-BFI
P34=1
0,2
12
100
BSD600R140-4
2,1 A
0,6
-
140
0140[5,5kW]
111
OD-BR100-BFI
P34=1
0,2
12
100
BSD600R82-4
2,7A
0,6
-
82
0180[7,5kW]
81
OD-BR100-BFI
P34=1
0,2
12
100
BSD600R75-4
2,8 A
0,6
-
75
0240[11 kW]
55
OD-BR100-BFI
P34=1
0,2
12
100
2 BSD-600R140-4
connected in parallel
4,1 A
1,2
-
70
0300 [15kW]
41
2 pieces of BSD-
2000R13-4 connected
in serial
12,4 A
4,0
-
26
0390 [18kW]
33
0460[22kW]
28
0610[30kW]
21
0720[37kW]
17
If other brake resistor than OD-BR100-BFI is used an external overload protection must be connected
between BFI and resistor. Put parameter P34=2 and design the protection using below formula:
Setting of external overload protection
= I =
√P/R