Product Description:

The RD51.1-4N-110-L-D1-FW is a drive controller produced by Bosch Rexroth Indramat and belongs to the RD 500 Drive Controllers series. This unit converts three-phase line power into a regulated output for induction motors, letting automation equipment adjust speed and torque as process demands change. It is intended for cabinet installation in material handling systems, pumping stations, and general factory machinery where programmable motor regulation improves throughput and energy use. Its function makes it suitable for applications that need controlled acceleration, adjustable running speed, and stable operation under varying process loads.

Its continuous output capacity is rated at 110 kW, meaning the controller can deliver enough current to operate large 400 V class motors at full mechanical load. The permissible line voltage spans 380 to 480 V, allowing the same unit to operate on nominal 400 V or 460 V supplies without a tap change. Input variation of up to ±10 % is accepted, so voltage dips or surges within that band do not interrupt normal operation. Motor flux is established through U/f curve control; this open-loop method keeps the volts-per-hertz ratio constant and provides predictable torque across the speed range. Power enters through a three-phase AC converter front end, in which the mains phases are rectified and then modulated by the inverter stage. This arrangement supports variable-speed operation without requiring separate external conversion hardware.

Thermal management relies on forced-air cooling, so filtered airflow must be maintained through the heat sink channels to keep semiconductor junction temperatures within limits. The unit is supplied without a built-in brake chopper, so rapid deceleration of high-inertia loads requires external dynamic braking hardware. An NAMUR terminal strip simplifies field wiring for status contacts and control signals. The auxiliary input for external 24 V standby power keeps the control electronics active during mains isolation, which helps preserve communication and diagnostic access when the power section is off. Generation 1 hardware is prepared for application-specific software selection through a separate ordering subposition.