Issue 10/06   3  Functions 
MICROMASTER 440      Operating Instructions   
6SE6400-5AW00-0BP0 
209 
Chopper
control
B-
B+
R
P1237 = 1
(5 %)
Chopper
control
B-
B+
R
P1237 = 3
(20 %)
R
R R
 
Fig. 3-79  Increasing the level of braking energy which can be absorbed 
The continuous power and the load duty cycle are modified using parameter P1237 
(setting values, refer to Fig. 3-80a). If the load duty cycle monitoring switches from 
the peak power (100%) to the continuous power, then this is dissipated for an 
unlimited length of time in the braking resistor (refer to Fig. 3-80b). Contrary to the 
braking resistor, as listed in Catalog DA51.2, the chopper control can be 
permanently operated with 100% power. 
t
t
cycle
P
DB
P
100
t
ON
t
OFF
P1237 t
ON
t
OFF
t
cycle
P
DB
5 % 12.0 228.0 240.0 0.05
10 % 12.6 114.0 126.6 0.10
20 % 14.2 57.0 71.2 0.20
50 % 22.8 22.8 45.6 0.50
100 % Infinite 0 Infinite 1.00
t
t
cycle
P
DB
P
100
t
100
t
P1237
t
OFF
a
b
 
Fig. 3-80  Chopper load duty cycle 
For MICROMASTER 440, up to and including Size FS F, the braking module is 
integrated in the drive inverter and the braking resistor can be connected via 
external terminals B+, B-.