Product Description:

Bosch Rexroth Indramat’s RD51.1-5N-045-L-LV-FW belongs to the RD 500 Drive Controllers series and is intended for variable-speed operation of standard induction motors in automated handling, pumping, or process equipment. Installed between the plant’s three-phase mains and the motor terminals, the controller modulates output frequency and voltage to match the load profile. This lets standard induction motors run at variable speed in automated handling systems, pump skids, and process equipment while reducing unnecessary energy use. By adjusting motor supply conditions as demand changes, the controller supports smoother operation during starts, slowdowns, and steady-state running.

The unit applies U/f curve control, a method that maintains a constant volts-per-hertz ratio so magnetic flux remains stable across the speed range. Thermal limits are managed by forced air cooling, and an internal fan moves air across the power semiconductors to remove switching losses during continuous operation. Because the device is supplied without a built-in brake chopper, applications that need rapid deceleration or frequent regenerative braking must use an external braking module. Output capability reaches 45 kW, which suits mid-frame motors used on conveyors and process pumps. The power section is rated for the 500 V class, so supply protection devices, motor insulation, and associated cabling must match that voltage category.

For grid connection, the controller is configured as a 3 x AC converter unit that rectifies three-phase input into a DC link for the inverter stage. Control logic and fieldbus nodes can remain active through a separate external 24 V stand-by power input, allowing parameter access and status monitoring when the main power link is disabled. High-frequency reflections on long motor leads are reduced by the integrated cable damping feedback (C3, D3) feature, which helps limit voltage overshoot at the motor terminals. The unit is part of design generation 1 in the RD 500 platform.