Lenze EMB9352−C - Manual (Page 79)

Dimensioning
Dimension brake chopper and brake resistor
5
l
79 EDBMB935X DE/EN/FR 13.0
5.3 Dimension brake chopper and brake resistor
Brake chopper and brake resistor are dimensioned in three steps.
Step 1: Calculate brake resistance
R
B
+
U
DC
2
P
gen,max
RB Brake resistance in W
U DC DC−bus voltage in V
P
gen,max
Max. regenerative power in W
Step 2: Determine the number of brake resistors
The value must not fall below the brake resistance R
B,min
:
U
ch
R
B,min
375 V 9 W
725/765 V 18 W
ƒ In step 1, R
B
< R
B,min
results in:
– Connect two or more brake choppers in parallel to achieve the required
resistance value. (
¶ 105)
ƒ In step 1, R
B
³ R
B,min
results in:
– You can use a brake resistor.
I
Tip!
Connect brake resistors of the same value in parallel. That way, the
calculation of the resulting resistance is easier.