Operation Principle And Hardware Description; Contents Of This Chapter; Product Overview; Operation Principle - ABB ACS880-604 Hardware Manual

Operation principle and
hardware description

Contents of this chapter

This chapter describes the operation principle and construction of the brake chopper.

Product overview

ACS880-604 is an air-cooled brake chopper unit. It includes an NBRA brake chopper
module or two parallel-connected NBRA brake chopper modules.

Operation principle

The brake chopper handles the energy generated by a decelerating motor. The chopper
connects the brake resistor to the intermediate DC circuit whenever the voltage in the
circuit exceeds the limit defined by the control program. Energy consumption by the
resistor losses lowers the voltage until the resistor can be disconnected.
Typically, a drive system is equipped with a brake chopper(s) if:
•
high capacity braking is needed and the drive cannot be equipped with a regenerative
supply unit
•
a backup for the regenerative supply unit is needed.
Standard resistors are available from ABB for each brake chopper module.

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