Product Description:

The RD51.1-7N-055-L-V1-FW is a drive controller produced by Bosch Rexroth Indramat within the RD 500 Drive Controllers series. It serves as the inverter stage in automated production cells, converting DC bus energy into variable-frequency and variable-voltage output for induction motors. By modulating the supply frequency, it allows machinery to accelerate, decelerate, or hold speed without relying on mechanical gearing. This operating method supports tighter process control and can reduce wear in conveyors, winders, and material-handling stations.

This controller belongs to design generation 1 and uses U/f curve control, so the ratio between stator voltage and frequency remains constant across the operating range to help keep motor flux stable. Thermal management is handled by Forced air cooling, which draws cabinet air across heat-sink fins to remove loss heat and maintain acceptable semiconductor temperatures. The power channel supplies a continuous output of 55 kW, making the unit suitable for medium-size pump and fan duties. Its DC bus accepts a working window of 530 to 670 V, allowing connection to rectifier units used with 400 V or 480 V mains.

The unit is supplied without a built-in brake chopper, so regenerative energy must be handled by external chopper and resistor hardware when braking demand is present. For the control electronics, it provides 24 V standby power from an external source, which keeps internal logic active during main disconnects and allows diagnostic functions to remain available. The DC link is fed from an Inverter DC supply section shared across multiple axes, which supports common bus layouts in coordinated drive systems. This arrangement is useful where several inverters operate from the same DC source and need consistent bus distribution throughout the cabinet.