Product Description:

The RS51.1-4G-031-V-NN-FW is produced by Bosch Rexroth Indramat as part of the RD 500 Drive Controllers series. Classified as a basic drive controller, it converts three-phase input power into a regulated output that can be matched to induction motors and other loads in automated machinery. Within an automation cell, the unit provides speed and torque regulation so actuators can follow programmed motion profiles and process requirements. This makes it suitable for equipment such as conveyors, pumps, and other variable-speed industrial systems. The controller is intended for cabinet-mounted installations where stable motor response is required during normal operating duty.

The controller connects to a plant power bus through a three-phase AC input and accepts line voltages in the range of 380 to 480 V. Its permissible supply fluctuation stays within a ±10 % window, allowing operation on feeders that experience moderate voltage variation, and within that range the unit can deliver a continuous apparent power of 31 kVA to the motor terminals. Closed-loop regulation is not used; instead, torque is shaped through U/f curve control, which helps keep stator flux nearly constant across the speed range. This control method suits general-purpose variable-speed applications that need stable motor operation without more advanced feedback functions. Harmonic distortion generated by the switching stage is attenuated by network components that include an integrated mains filter, which helps reduce conducted emissions back onto the supply and limit electrical noise on the incoming line.

A built-in brake chopper and resistor dissipates excess DC bus energy during rapid deceleration, so an external dump module is not required. This is useful in applications with frequent stopping cycles or loads that return energy during braking. The unit uses design generation 1, so cabinet cutouts and connector positions match other first-generation RD 500 units. The product family designation Basic Drive indicates that extended application functions are not included. Because the braking components are integrated, the power section remains compact and panel wiring stays straightforward during installation.