Product Description:

The RD51.1-4B-055-L-VY-FW is a drive controller produced by Bosch Rexroth Indramat within the RD 500 Drive Controllers series. Intended for cabinet installation in material-handling lines, presses, and continuous-process equipment, the unit converts three-phase mains power into regulated AC output for induction motors. By modulating voltage and frequency, it supports closed-loop speed adjustment so a PLC or fieldbus interface can coordinate motor torque with changing mechanical load in automated production. This makes the controller suitable for variable-speed duties that need repeatable acceleration and deceleration during normal production changes.

Its continuous output is rated at 55 kW, which suits mid-range pumps, fans, and conveyors that require substantial shaft power without an oversized cabinet. The controller accepts line voltages from 380 to 480 V and tolerates supply variation of ±10 %, allowing stable operation on common industrial power systems. The input stage uses a three-phase AC converter topology, and motor control is managed through U/f curve control to keep motor flux stable across the speed range. Internal heat is removed by forced-air cooling, which supports continuous operation when the drive is installed in enclosed panels with proper airflow.

A built-in brake chopper connects to an external resistor so regenerated energy can be dissipated during rapid deceleration or overhauling loads. An integrated mains filter helps reduce conducted interference on the supply line and limits the need for separate filtering components in the cabinet. The drive also includes the Y1 + V1 combination function package, which supports both vector-oriented behavior and standard V-operation settings on the same platform. The unit is generation 1 hardware, making it suitable for installations that rely on the established RD 500 control structure rather than newer drive families.