Product Description:

The RD51.1-5B-003-D-DF-FW is a drive controller manufactured by Bosch Rexroth Indramat for the RD 500 Drive Controllers series. It serves as the power conversion and motor-control stage in automated lines, translating low-level setpoints into regulated voltage and frequency for induction machines. Installed between a supervisory PLC and the plant's motors, the unit maintains programmed speeds while monitoring load conditions during routine operation. Its operating profile suits conveyors, pumps, and other material-handling duties that need steady variable-speed control rather than highly dynamic servo response.

For continuous duty, the controller delivers 3.0 kW of output. Its regulation method is U/f curve control, which keeps the voltage-to-frequency ratio constant so torque remains stable across the usable speed range. A built-in brake chopper dissipates regenerative energy during rapid deceleration, reducing DC-bus overvoltage without added external hardware. Thermal losses are removed through a plug-through cooler, which transfers heat outside the cabinet and reduces the thermal load on internal electronics. The power section uses a three-phase AC converter mains connection, and this layout supports the standard supply arrangement used by the drive platform.

Input lines can reach 500 V, matching plant power systems used in larger industrial installations. For field wiring, the controller provides a NAMUR terminal strip with external 24 V standby power, so connected sensors and signaling circuits can remain energized when the main supply is unavailable. Drive diagnostics include current filter feedback (U6, V6, W6), which passes filter-related status information to the higher-level controller for monitoring. This signal path gives the control system direct visibility into the monitored phases during normal speed regulation and changing load conditions.