Siemens SINAMICS G130 Engineering Manual page 183

Continuous braking power
Power permitted for 15 s in 90 s cycles
Power permitted for 20 s in 90 s cycles
Power permitted for 40 s in 90 s cycles
Load duty cycle diagram and power definitions
Calculation of the P power
20
P = 4.5 x mean breaking power
20
no
Peak power x 0.8 ≥ P
P = 4.5 x mean breaking power
20
The ON/OFF states of the Braking Module are controlled by a 2-point controller. To reduce the voltage stress on the
motor and converter, the response threshold at which the braking unit is activated and the DC link voltage generated
during braking can be reduced. For example, the DC link voltage for the converters in the voltage range 380 V to
480 V can be reduced from 774 V to 673 V. This also reduces the attainable peak power. In this case, a factor of 1.06
should be applied instead of 0.8.
The response thresholds are shown in the following table.
Line supply voltage
380 V – 480 V 3AC
500 V – 600 V 3AC
660 V – 690 V 3AC
Response thresholds of braking units
20
P = 0.8 x Peak power
20
Braking unit response threshold
774 V or 673 V
967 V or 841 V
1158 V or 1070 V
Engineering Information
yes
SINAMICS Engineering Manual - May 2008
SINAMICS G130
183/396
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