Product Description:

The RD51.1-4N-005-L-NN-FW is a drive controller from Bosch Rexroth Indramat in the RD 500 Drive Controllers series. It regulates the voltage and frequency supplied to AC induction motors so conveyor lines, pumps, and mixing equipment can run at the speed required by each process stage. By varying motor speed instead of running the load at full line frequency, the unit supports smoother process control and better matching between motor output and machine demand. This operating role makes it suitable for variable-speed applications that need stable motor control without a dedicated servo feedback system.

It relies on U/f curve control, which keeps a constant ratio between stator voltage and frequency so the motor can maintain usable torque without feedback devices. The controller has a rated output of 5.5 kW, which suits mid-range asynchronous motors used in auxiliary axes and material-handling sections. Its input circuit accepts 380 to 480 V, and operation remains stable when the mains stays within the declared ±10 % tolerance band. An integrated mains filter reduces conducted emissions and helps the installation meet EMC limits without a separate external filter. This arrangement also helps limit electrical noise returning to the supply lines.

Thermal management is handled by forced air cooling, so the unit requires an unobstructed airflow path and ambient temperatures below its derating point. The drive is supplied without a built-in brake chopper, so regenerative energy from rapid deceleration must be handled by external braking equipment or returned to the plant supply. Power is derived from a 3 x AC converter front end, which means three-phase input is rectified and then pulse-width modulated to the motor output terminals. The unit is design generation 1, identifying the first-generation RD 500 layout used for this model. This layout is intended for standard variable-speed duties rather than extended integrated functions.