Product Description:

The RD51.1-4B-015-L-F1-FW is a drive controller produced by Bosch Rexroth Indramat within the RD 500 Drive Controllers series. It is installed between a three-phase AC supply and an induction motor to regulate speed and torque in equipment such as material-handling lines, mixers, and pump stations. By converting fixed-frequency utility power into variable-frequency output, the unit supports precise process control and provides the interface signals needed for coordination with higher-level PLC systems in industrial plants.

This controller operates on input voltages from 380 to 480 V and is designed for a three-phase AC converter input. Within that range, its power stage delivers a continuous output of 15.0 kW, which suits medium-duty motor applications that require stable speed regulation under changing load conditions. Motor flux is maintained through U/f curve control, which raises stator voltage in proportion to output frequency so the magnetic circuit remains stable during acceleration and low-speed operation. Thermal limits are managed by forced-air cooling, and the internal fan moves ambient air across the heat sink to keep the power semiconductors within their allowable operating temperature during sustained use.

A built-in brake chopper handles regenerated energy during deceleration, helping protect the DC link from overvoltage when the connected motor is slowing a load with high inertia. An integrated line filter reduces conducted electrical noise and can simplify cabinet layout by reducing the need for separate external filtering components. The drive accepts input variation within ±10 %, which helps it continue operating through moderate line fluctuations without unnecessary trips. Diagnostic functions provide current-feedback output signals (U6, V6, W6), allowing supervisory controls to monitor phase current behavior in real time and respond to changing process conditions.