Product Description:

The RD51.1-4B-030-L-C1-FW is a Bosch Rexroth Indramat drive unit in the RD 500 Drive Controllers series. It is installed in control cabinets to manage the operating speed of three-phase induction motors on conveyors, pumps, and material-handling axes. By converting fixed-frequency line power into an adjustable output, the unit allows production equipment to match motor torque to real-time process demands while reducing energy losses and mechanical wear. The device fits into existing automation architectures and exchanges status or command signals with higher-level PLCs through standard I/O channels.

The power section is a three-phase AC converter, so the drive accepts three-phase line supplies. Its permitted input spans 380 to 480 V, with a tolerance window of ±10 % that keeps the inverter operating when plant voltage deviates from nominal. Within this range, the module delivers a continuous output of 30 kW to the connected motor. Speed modulation is based on U/f curve control; the controller maintains a proportional relationship between output voltage and frequency, helping the motor keep stable magnetic flux during acceleration and partial-load operation. This generation 1 design uses application-specific parameters matched to the intended task.

Thermal and protective features are integrated into the hardware. A built-in brake chopper dissipates regenerative energy during rapid deceleration, preventing DC-bus overvoltage. Heat generated by the IGBTs is removed through forced air cooling, so cabinet airflow must be maintained to preserve component life. Line-side disturbances are attenuated by the integrated line filter, allowing the drive to meet typical plant EMC limits without additional external filters. For the control electronics, the unit can be supplied from a separate circuit that provides 24 V stand-by power. This keeps the control board active for communication and parameter retention even when the main converter is de-energized.