Product Description:

Bosch Rexroth Indramat manufactures the RD51.1-4B-200-F-V1-FW drive controller within its RD 500 Drive Controllers series. This Generation 1 design serves as the central inverter for asynchronous motors on conveying, pumping, or forming equipment, where variable speed is required for cycle coordination and energy savings. By altering the voltage and frequency delivered to the motor windings, the unit supports automated lines that must switch between low-speed positioning and full-speed throughput without mechanical gear changes.

Electrically, the controller operates on a three-phase AC converter supply architecture and accepts line potentials from 380 to 480 V. Within that window, it maintains functionality even when the line supply varies by ±10%, which helps prevent interruptions during moderate grid instability. Once energized, the inverter section can furnish up to 200 kW of output power to the motor terminals. Speed regulation follows a U/f curve control scheme, so the flux level in the machine remains constant across the programmed frequency range, keeping torque predictable during both acceleration and steady-state loading.

The controller also includes cooling and protection functions needed for continuous industrial duty. A forced-air cooling with integrated liquid circulation assembly transports heat from the power semiconductors to external air streams, enabling continuous operation at high current density. Regenerative energy produced during braking is routed to a built-in brake chopper, permitting quick deceleration without stressing the DC link. Line-side harmonics are attenuated by an integrated mains filter, and machine logic can stay active through power outages because an external 24 V stand-by power connection keeps the control electronics alive until line power returns.