Product Description:

The RD51.1-5N-005-L-D1-FW is a drive controller built by Bosch Rexroth Indramat within the RD 500 Drive Controllers series. Intended for inverter-based motor control in automated machinery cells and process lines, it regulates induction motor speed and torque by adjusting output frequency and voltage. In plant installations, it serves as the intermediary between the three-phase mains and the motor circuit, providing conversion, protection, and parameter handling suited to discrete manufacturing and continuous-process applications. That role makes it suitable for equipment that requires adjustable motor speed during startup, normal running, and changing process conditions.

At its core, the unit employs U/f curve control, so voltage follows a preset ratio to frequency; this open-loop method supports standard induction motors without encoder feedback. This control approach is often used where simple speed regulation is sufficient and tight servo feedback is not required. The controller delivers a continuous mechanical output of 5.5 kW, which suits small to mid-frame pump, fan, and conveyor drives. It is powered through a three-phase AC converter front end that accepts line potentials up to 500 V, allowing direct connection to industrial distribution networks. Because it is supplied without a built-in brake chopper, excess regenerative energy must be handled by external braking equipment when the load decelerates.

Heat is removed by forced air cooling, so cabinet airflow must be maintained to keep semiconductor temperatures within acceptable limits. Field wiring is simplified by the integrated NAMUR terminal strip, which provides a clear connection point for control and signaling circuits. Control electronics can remain active through an external 24 V standby power input, allowing status retention and controlled shutdown behavior during a mains interruption. The standby supply helps preserve control functions that must remain available for monitoring and orderly restart behavior. The unit is part of Design Generation 1, which places it in the first release of the RD 500 platform.