Product Description:

The RD51.1-4N-003-L-C1-FW is a drive controller produced by Bosch Rexroth Indramat within the RD 500 Drive Controllers series. Designed for plant and machine automation, this unit conditions three-phase input power and delivers a regulated output to standard induction motors for adjustable-speed operation. It supports speed and torque adjustment through scalar voltage-to-frequency logic, making it suitable for applications where closed-loop vector control is unnecessary. The controller fits cabinet installations that require dependable conversion, basic motor control, and protective monitoring during routine industrial duty.

It uses U/f curve control to keep motor magnetization constant across the speed range, making it suitable for pumps, fans, and simple conveyors. The power section accepts line voltages from 380 to 480 V with a tolerance of ±10 %, so the drive can remain operational on common industrial supply variations. At a rated output of 3.0 kW, the module can operate medium-frame motors used on utility-duty equipment. Heat is removed by forced air cooling, which helps the enclosure manage thermal load during continuous operation. The unit belongs to design generation 1, and its three-phase AC converter topology places the rectifier and inverter in one housing to reduce internal wiring length.

The controller has 3 x AC converter input terminals, which keep incoming power connections grouped at the main section. A control relay can keep the electronics energized through the 24 V stand-by power connection while the motor is idle, allowing the unit to remain ready without full power conversion. The drive is supplied without a built-in brake chopper, so regenerative braking requires an external resistor. EMC performance is supported by an integrated mains filter, which reduces conducted interference on the incoming supply. This arrangement is useful where clean power entry and simple braking configuration are both required.