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Entry type: Application example Entry ID: 22101908, Entry date: 04/29/2008

MICROMASTER: Engineering braking chopper operation

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  • Associated product(s)


Due to differences in the parameter structure:

  • this application only applies to MICROMASTER 4 and SINAMICS CU240x with Firmware < V4.0
  • this application cannot be used for SINAMICS CU230.


For several applications, under certain operating states, the motor can go into regenerative operation (braking). This can cause the DC link voltage to increase and finally fault F0002 is then output which means DC link overvoltageover voltage. Generally, this occurs for drives with higher load moments of inertia, if the speed setpointset point is to be quickly reduced, or the load braked.



For MICROMASTER 440 and SINAMICS G120 with PM240, sizes A-F, the integrated chopper can be disconnected and an external (optional) braking resistor used for braking. Information on the mode of operation and engineering the braking chopper and regenerative operation is provided in the following application description.


Principle design of the MM440 and G120 drive converter with braking chopper


Increasing the continuous braking power using 4x MM440/G120 braking resistors



Content of Downloads


Documentation (English) PDF_Engineering_braking_chopper_operation_V1_2_en.pdf ( 444 KB )





March 2004 Version 1.0 - First edition
June 2006 Version 1.1
March 2008 Version 1.2 - Text revised, insert G120/PM240 data

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