Product Description:

The RD51.1-4N-015-L-DF-FW is a drive controller produced by Bosch Rexroth Indramat in the RD 500 Drive Controllers series. Designed for cabinet mounting inside automated machinery, it regulates the speed and torque of three-phase induction motors used on conveyors, mixers, and general plant equipment. By adjusting output frequency and voltage in real time, the unit serves as the primary interface between mains power and motor-driven motion in an industrial automation cell. This allows connected machines to run at process-matched speeds instead of fixed line frequency alone. It is intended for variable-speed duties where smooth acceleration and controlled torque are more suitable than direct-on-line motor starting.

The controller uses a 3 x AC converter topology and accepts line voltages in the 380 to 480 V range. It can accommodate mains fluctuations within ±10 %, reducing sensitivity to normal supply variation. The power stage is rated for 15.0 kW of continuous motor output and applies U/f curve control to match output voltage to frequency and maintain motor flux. This control method keeps the output relationship straightforward across the operating range. An integrated mains filter reduces conducted emissions, and current feedback from the U6, V6, and W6 paths is returned to the control section for protective limiting.

The hardware platform is part of Design Generation 1 and uses forced air cooling to move heat through the exhaust channel. This arrangement supports side-by-side mounting in compact control panels without wide spacing between units. The drive is supplied without a built-in brake chopper, so an external dissipative module is required for frequent deceleration or high-inertia braking loads. A NAMUR terminal strip provides galvanically isolated I/O, and an auxiliary 24 V stand-by input keeps the control electronics active during a main power loss so status and diagnostic functions can remain available.