SIEMENS
SINAMICS S150 NEMA
Engineering Information
3
Siemens D21.7
(Part 2) – 2015
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Braking units, maintenance accessory
Example
The design of the braking unit is to be calculated for a 200HP
(132 kW) drive.
The mean braking power is calculated as follows:
The Mean braking power = 90 kW x 17 s / 90 s = 17.0 kW
P
20
= 4.5 x 17.0 kW = 76.5 kW
Peak power = 0.8 x 90 kW = 72.0 kW
Result:
The mean braking power is the determining factor in the
configuration of the braking module and braking resistor,
i.e. a braking unit ≥ 76.5 kW should be provided.
The 100 kW braking unit is suitable.
When the response threshold is reduced, the required
braking power
P
20
is calculated as follows:
Mean braking power = 90 kW x 17 s / 90 s = 17.0 kW
P
20
= 4.5 x 17.0 kW = 76.5 kW
Peak power = 1.06 x 90 kW = 95.4 kW
Result:
The peak power to be generated is the determining factor
in the configuration of the braking module and braking
resistor, i.e. a braking unit ≥ 95.4 kW should be provided.
The 100 kW braking unit is suitable.
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