Product Description:

The RD51.1-7N-132-R-NN-FW is an AC inverter manufactured by Bosch Rexroth Indramat for the RD 500 Drive Controllers series. The device converts a fixed intermediate DC link into a variable output that matches the torque and speed requirements of three-phase induction motors. Under PLC supervision, the controller supports closed-loop speed control in material handling, ventilation, and processing lines where synchronized acceleration and stable motor response are important. This operating method also allows the machine to adjust motor speed to changing process demand without mechanical speed-changing components.

In operation, the unit uses U/f curve control, so the voltage-to-frequency ratio remains constant across the speed range and helps prevent magnetic saturation in the motor core. Thermal management relies on liquid cooling with an internal pump, which removes heat from the power semiconductors without depending on ambient airflow. The DC bus accepts a nominal range of 530 to 670 V, and the inverter section is supplied from an inverter DC link instead of direct mains, which supports centralized rectification and common-bus energy sharing. When applied to demanding loads, the drive provides a rated power of 132 kW for large fans, compressors, or extruders.

The unit is supplied without a built-in brake chopper, so regenerated energy that must be dissipated quickly requires external dynamic-braking components. It belongs to design generation 1, which shares its mounting dimensions and parameter structure with other RD 500 variants. Auxiliary application modules are not installed, leaving the front slots open for later function cards when additional process feedback or fieldbus communication is needed. This base configuration keeps the hardware focused on inverter operation while still allowing later expansion through optional interface cards.