Product Description:

The RD51.1-4B-200-R-V1-FW drive controller is manufactured by Bosch Rexroth Indramat as part of the RD 500 Drive Controllers series. Designed for high-power inverter cabinets, this unit converts three-phase mains power into regulated motor voltage and frequency for large induction machines used in conveying, pumping, and continuous-process lines. It provides open-loop speed regulation for heavy industrial automation applications that do not require feedback-based vector control. This operating method is commonly used where process continuity matters more than rapid point-to-point positioning. Its control approach suits systems that need stable motor operation across demanding industrial duty cycles.

The controller delivers a continuous output of 200 kW and draws power from mains between 380 to 480 V. The input window allows a tolerance of ±10 %, so the unit can operate on grids with moderate voltage fluctuations. Incoming energy is processed through a 3 x AC converter front end that rectifies and inverts the supply to match the programmed operating profile. Thermal management is handled by liquid cooling with an internal pump, and the internal circuit circulates coolant across the heat sink to keep semiconductor junction temperatures within limits. Because the cooling circuit is contained inside the unit, cabinet airflow demands can be reduced compared with those of large fan-cooled drives.

A built-in brake chopper absorbs regenerated energy during rapid deceleration and helps prevent DC-link overvoltage. An integrated mains filter reduces conducted emissions on the supply connection. Speed adjustment relies on U/f curve control, which gives predictable torque response without encoder feedback. For the control electronics, a 24 V standby power input keeps the logic active when the main supply is isolated and helps preserve communication and stored parameters. This allows the control section to remain available for supervision and restart coordination while the power section is disconnected.