Product Description:

The RS51.1-4G-050-L-NN-FW is a basic drive produced by Bosch Rexroth Indramat for the RD 500 Drive Controllers series. As a converter-based drive controller, it regulates three-phase induction motors in continuous-duty automation lines where speed is set by an adjustable frequency. The unit provides the power interface between the mains supply and the motor, executes scalar voltage-to-frequency regulation, and includes protective hardware for dynamic braking and line filtering. This operating method is well suited for conveyors, pumps, and fans that need adjustable motor speed without closed-loop servo control.

Its rated output is 50 kVA, allowing it to supply sizable production motors without derating. The input section accepts a three-phase mains range of 380 to 480 V and continues to operate properly when the line fluctuates by ±10 %. Because the supply category is a Converter 3 × AC, the device rectifies and inverts incoming utility power rather than using a DC bus from an upstream source. Motor voltage follows a U/f curve control profile, so stator flux remains stable across the speed range and the drive can support steady operation in constant-torque and variable-torque applications.

Thermal management relies on forced air cooling, and a rear-mounted fan draws cabinet air through the heatsink to remove switching losses generated at the rated current. DC overvoltage events are dissipated by the embedded braking stage identified as built-in brake chopper and resistor, eliminating the need for an external energy dump. Line-side disturbance is suppressed by the integrated mains filter, which helps reduce conducted noise on the incoming supply. This controller is classified as design generation 1 and uses the standard drive configuration for general industrial motor control.