Product Description:

The RD51.1-4B-315-F-NN-FW is a drive controller produced by Bosch Rexroth Indramat within the RD 500 Drive Controllers series. The unit regulates the speed and torque of three-phase induction motors in automated machinery by adjusting output frequency and voltage according to demand. It connects between the line supply and the motor, converting constant input power into a variable AC waveform so production equipment can run at commanded speeds, reduce energy use, and start smoothly under load. This operating role suits process equipment that needs controlled acceleration and stable motor speed during changing load conditions.

This model delivers a rated output of 315 kW, allowing it to handle high-power pump, fan, or conveyor loads. It accepts a line supply of 380 to 480 V and remains functional when input variation stays within ±10 %, which helps reduce nuisance trips in facilities with unstable power. The input side uses a three-phase AC converter, so line power is rectified and modulated internally before being sent to the motor. Motor regulation follows U/f curve control, meaning voltage rises in proportion to frequency to help maintain safe magnetic flux across the speed range.

An internal built-in brake chopper diverts regenerative energy to an external resistor during deceleration, which helps prevent DC bus overvoltage. The cabinet already houses an integrated mains filter, so additional line filters are not required for standard EMC limits. Thermal management relies on forced air cooling with integrated liquid circulation; air moves across heat sinks while an internal liquid loop carries heat to the cooling interface for continuous full-load operation. It is a design generation 1 device, and the base unit ships without optional function modules for expanded control features.