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System Manual V2 – MOVITRAC® B
6
Connecting AC brakemotors
Project Planning
Calculation
example
Given:
•
Peak braking power 13 kW
•
Average braking power 6.5 kW
•
Cyclic duration factor cdf 6 %
Required:
•
BW.. braking resistor
Procedure
•
The 100 % cdf power for wire and grid resistors is initially calculated using the follow-
ing formula:
Average braking power / overload factor (wire / grid resistor)
Refer to the diagrams for the overload factor (wire and grid resistor) with a cyclic
duration factor (cdf) of 6 %.
•
Results:
100 % cdf power for wire resistors: 685 W.
100 % cdf power for grid resistors: 856 W.
•
The
maximum braking resistance value is 72
for a peak braking power of 13 kW
when using a
MC07B...-5A3 (AC 400/500 V unit
) (→
Peak braking power table).
•
Select the appropriate braking resistor from the assignment tables with the following
points:
– Max. permitted braking resistance value
– MOVITRAC
®
unit used
Result when using MC07B0110-5A3, for example: BW039-12
6.9
Connecting AC brakemotors
For detailed information about the SEW brake system, refer to the "Gearmotors"
catalog, which you can order from SEW-EURODRIVE.
SEW brake systems are disc brakes with a DC coil that release electrically and brake
using spring force. A brake rectifier provides the brake with DC voltage.
NOTE
The brake rectifier must have a separate supply system cable for inverter operation; it
must not be powered using the motor voltage!
Summary of Contents for MOVITRAC MC07B0037-2A3-4-00
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