Product Description:

The RD51.1-4N-011-L-CF-FW is a three-phase AC drive controller produced by Bosch Rexroth Indramat and assigned to the RD 500 Drive Controllers series. This unit converts fixed-frequency mains power into a variable output so that induction motors can be regulated continuously in conveyors, pumps, and material-handling equipment. By changing the frequency and amplitude of the output, the controller allows production lines to match motor speed to process demand while reducing mechanical stress and energy consumption. This also helps support smoother speed changes during normal operation.

The control algorithm relies on U/f curve control, which maintains a constant ratio between output voltage and frequency to protect motor magnetization at each speed setpoint. The power stage uses a three-phase AC converter topology, which means the rectifier requires a symmetrical three-phase supply. Acceptable input falls within a 380 to 480 V voltage range, and within that band the device tolerates line deviations of ±10 %, so it can continue operating during moderate grid fluctuations. A factory-installed integrated mains filter attenuates conducted emissions, allowing the drive to meet EMC limits without external line reactors or filters.

Thermal management is handled by forced-air cooling, with an internal fan moving air across the heat sink to keep semiconductor junction temperatures within limits. Because the drive is supplied without a built-in brake chopper, applications that need dynamic braking require an external chopper and resistor to dissipate regenerated energy. The unit includes the combination C1 + F1 function package, so the controller supports standard drive functions together with an extended frequency inverter feature set. The unit is part of design generation 1, which matches first-generation RD 500 option cards.