Product Description:

Bosch Rexroth Indramat manufactures the RD51.1-5B-045-D-D1-FW as a member of the RD 500 Drive Controllers series. This drive controller converts fixed-frequency mains power into a variable output for industrial induction motors, allowing precise speed regulation in automated lines, packaging equipment, and similar motion-based processes. Because the output frequency can be adjusted independently of line frequency, the drive can match motor speed to process demand instead of running only at full mains speed. It is intended for applications that require controlled acceleration, stable running speed, and repeatable operation under changing load conditions.

The controller uses U/f curve control, so the output voltage rises in proportion to frequency to maintain motor flux during acceleration and deceleration. Its nominal output is rated at 45 kW for continuous duty. The input range is centered on 500 V, which matches common 480 V three-phase supplies with minimal derating. The input stage uses a three-phase AC converter, so incoming AC power is rectified and then pulse-width modulated for motor control. This control method is well suited to general industrial speed control where smooth operation is more important than servo-level dynamic response. For rapid stops or overhauling loads, a built-in brake chopper routes regenerated energy to an external resistor and helps prevent DC bus overvoltage.

Thermal management is handled by a plug-through cooler for units up to 110 kW, with the heat sink extending outside the cabinet so losses are discharged without raising enclosure temperature. This arrangement helps keep excess heat out of the enclosure and reduces the thermal burden on nearby control components. Field wiring terminates on a NAMUR terminal strip with external 24 V standby power, which lets logic circuits remain energized while main power is isolated for interlocks and diagnostics. The standby supply supports control continuity during shutdown states that still require signal handling. The unit belongs to design generation 1, aligning it with the first release of RD 500 accessories, parameter files, and service tools.