Product Description:

The RD51.1-7N-018-L-V1-FW belongs to the RD 500 Drive Controllers series by Bosch Rexroth Indramat. It functions as a variable-speed drive controller that converts a DC link supply into three-phase output for induction motors used in conveyors, pumps, and other automated plant equipment. By regulating motor frequency and voltage according to a predefined curve, the unit supports precise speed adjustment and lower energy use in industrial automation lines. This operating method helps process equipment respond to changing load conditions without relying on fixed-speed motor operation.

This controller delivers a rated output of 18.5 kW, so its power stage is suited to medium-capacity machinery. The DC bus input must remain between 530 to 670 V, a range that matches common rectifier modules used on 400 V mains systems. Motor excitation follows U/f curve control, so voltage rises with frequency to keep magnetic flux stable during acceleration and under varying load. Thermal management relies on forced air cooling, and an integrated fan moves air across the heat sinks to keep semiconductor temperatures within a safe operating range. Because the device expects an inverter DC supply rather than direct AC, it is typically installed on a shared DC bus where several drives can operate from the same rectifier section.

The unit is supplied without a built-in brake chopper, so applications that require rapid deceleration must use an external dissipation module. Control electronics remain active through 24 V standby power, which allows parameter access and status monitoring even when the main bus is de-energized. The unit is built in design generation 1, indicating the first design version of this model. The required software is ordered separately, allowing the drive package to be matched to the intended control functions.