Product Description:

The RD51.1-4N-055-W-V1-FW belongs to the RD 500 Drive Controllers series from Bosch Rexroth Indramat. It is a drive controller intended for variable-speed operation of three-phase induction motors in industrial automation cells, conveyors, and pump stations. By regulating the motor’s stator frequency and voltage, the unit allows precise adjustment of shaft speed and torque while maintaining stable process conditions. This operating method helps equipment respond smoothly to changing load demands and supports controlled acceleration and deceleration in continuous-duty industrial systems. It is suited to processes in which fan, pump, or conveyor speed must be matched to throughput rather than run only at full line frequency.

Its power stage is rated for 55 kW, making it suitable for medium-size production lines and HVAC compressors. Motor excitation follows U/f curve control, so voltage scales with frequency to help maintain magnetic flux across the normal speed range. The converter connects to mains within 380 to 480 V and can accommodate line variations up to ±10 % without derating. An integrated mains filter attenuates conducted emissions, which can simplify panel integration by reducing the need for separate filtering hardware. The unit is a Generation 1 model and supports application-specific operating functions through its control platform. Because the control method maintains a proportional voltage-to-frequency relationship, the drive can deliver predictable torque behavior during steady-state operation at different commanded speeds.

Thermal stability is secured through liquid cooling, which transports heat directly to an external exchanger and helps keep cabinet air temperatures low during sustained operation. Power is supplied through a Converter 3 x AC front end that rectifies and smooths the incoming line before the IGBT bridge. For applications requiring rapid deceleration, the unit is supplied without built-in brake chopper, so braking components must be provided externally. The control electronics remain energized by a 24 V stand-by power source, allowing communication and stored parameter data to remain available even when the main inverter section is disabled. Keeping the low-voltage control section active also allows status exchange with higher-level equipment while power conversion to the motor is turned off.