Product Description:

The RD52.1-4B-075-D-F1-FW is a drive controller manufactured by Bosch Rexroth Indramat as part of the RD 500 Drive Controllers series. It serves as the power-conversion stage between a three-phase utility supply and the motors of automated equipment, providing regulated current so axes can accelerate, decelerate, and hold speed under closed-loop control. In factory automation, this unit is selected when a single modular inverter must manage medium-power conveyors, extruders, or pump stations that demand high dynamic accuracy.

The controller delivers a continuous output of 75 kW, giving it enough margin for motors that draw roughly 150 A at peak torque. It accepts line voltages from 380 to 480 V, so it can be wired directly to common industrial mains without an autotransformer. The supply interface uses a 3 x AC converter that rectifies and smooths each phase before the inverter bridge recreates a variable-frequency output. Inside the control core, field-oriented vector control resolves stator currents into flux-producing and torque-producing components, allowing the drive to hold tight speed tolerance even at low speeds. Thermal energy is removed through a plug-through cooler, a heat sink that projects outside the enclosure wall to transfer heat directly to cabinet exhaust air and keep internal electronics below their 85 °C limit.

A built-in brake chopper diverts regenerated energy into an external resistor so the DC bus voltage stays within safe limits during rapid deceleration. The front end contains an integrated mains filter that attenuates conducted emissions and helps the cabinet meet EN 61800-3 limits without extra line reactors. Input fluctuations are handled by a ±10% input tolerance window, which reduces nuisance trips on weak grids. For diagnostic purposes, the controller provides current filter feedback signals U6, V6, and W6, which a PLC can log to verify harmonic suppression. This is a generation 1 design.