Product Description:

The RD52.1-4B-011-L-NN-FW is a drive controller manufactured by Bosch Rexroth Indramat and assigned to the RD 500 Drive Controllers series. Installed between the line supply and an induction or synchronous motor, it converts fixed-frequency three-phase power into a variable voltage and frequency output for accurate speed and torque regulation. The unit serves as the central actuator interface for conveyors, mixers, or positioning modules that need coordinated motion profiles. Because the output frequency is adjustable, the controller can match motor speed to process demand instead of forcing the motor to run at fixed line frequency. By integrating control electronics, protective monitoring, and power semiconductors in one housing, it reduces cabinet wiring and simplifies setup.

A built-in brake chopper lets the controller divert regenerative energy into a resistor, preventing DC-link overvoltage during rapid deceleration. The current loop is calculated with field-oriented vector control, so both torque and flux are adjusted in real time for smooth low-speed operation and fast transient response. Thermal management relies on forced air cooling, which moves cabinet air across the heat sink to keep semiconductor temperatures within a safe operating range. The power section is designed for a three-phase AC converter supply and accepts line voltages from 380 to 480 V, giving flexibility for plants that operate on either 400 V or 460 V utility systems. This arrangement supports stable operation in applications where load demand changes quickly during acceleration, running, and stopping.

System integration is simplified by an integrated line filter, which attenuates conducted emissions so additional external EMI hardware is often unnecessary. Input variation of up to ±10 % is permitted, allowing the controller to maintain consistent output even when the service transformer is lightly loaded or subject to transient dips. The filter and voltage tolerance help the unit operate reliably on industrial power systems where line conditions are not perfectly constant. As design generation 1, it shares the mechanical layout and parameter structure used across first-release RD 500 units. The unit uses separately ordered firmware, and the blank Functions code indicates that no optional application macros are preloaded.