Product Description:

The RD51.2-4B-015-P-A2-FW drive controller is manufactured by Bosch Rexroth Indramat as part of the RD 500 Drive Controllers series. As a closed-cabinet inverter, it modulates the voltage and frequency supplied to standard AC motors, allowing automated machinery to start smoothly, run at variable speeds, and match load conditions without mechanical gear changes. By integrating control, power conversion, and protective functions in one unit, the product supports compact installation in material-handling lines, packaging systems, and general-purpose process equipment.

The controller uses U/f curve control, so motor flux is maintained by keeping the stator voltage proportional to frequency. This method works well for pumps and fans that do not require encoder feedback. Nominal output is rated at 15.0 kW, giving sufficient power for medium-sized drive applications. Incoming supply must be within 380 to 480 V on a three-phase line, and the unit tolerates mains deviations of ten percent without derating. The front end uses a 3 x AC converter, which rectifies the line input and produces a DC link that the inverter section switches into a sinusoidal output. These ratings help match the controller to the available supply and the connected motor.

Additional hardware completes the regulation scheme. A built-in brake chopper links the DC bus to an external resistor so regenerated energy is dissipated during rapid deceleration. Line interference is suppressed by an integrated mains filter, reducing conducted emissions toward neighboring equipment. Thermal management is handled by a heat dissipation panel that is adequate for devices up to 18.5 kW, so no separate forced-air unit is needed at this power level. For safety and energy savings, the unit offers external stand-by power and a starting lock-out that inhibits unintended restarts. The design generation is 2.