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Liquid-cooled brake chopper units

Brake units are used for resistor braking. They handle the energy generated by decelerating motors for example in emergency stopping. Whenever the voltage in the common DC bus exceeds a certain limit, a brake unit connects the bus to a braking resistor.

The offering includes two different braking concepts. The main difference between the concepts is controllability:
  1. One-phase brake unit (frame NBRW), on-off controlled (no modulation). Brake current depends only on the resistance of the brake resistor. Compact and cost efficient. Used mainly in single drives.
  2. Three-phase dynamic brake unit with modulating control (frame R8i). Brake current/power is controlled. Used in single drives and multidrives.


Power range:

  • 404 to 2422 kW (Pbrmax) / 690 V for one-phase brake unit (NBRW)

  • 870 to 5200 kW (Pcontmax) / 690 V for three-phase dynamic brake unit (R8i)

Compact units
Easy installation
High instantaneous braking capability
Designed for both single drive configurations and common DC bus drives
Extensive selection of mechanical and electrical accessories



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