Product Description:

The RD51.1-5B-015-L-DF-FW is a drive controller manufactured by Bosch Rexroth Indramat and assigned to the RD 500 Drive Controllers series. In an automation cell, it links the mains supply to an induction motor, modulating voltage and frequency so that conveyor sections, pumps, or mixers can be started, stopped, and speed regulated from a PLC or local keypad. By converting three-phase power to a variable output waveform, the unit provides electronic motor control without mechanical gear changes. This supports processes that need adjustable motor speed during normal operation.

This controller employs U/f curve control. The controller maintains a fixed volts-per-hertz ratio so that motor flux stays constant while the speed command varies. Thermal management relies on forced air cooling; an internal fan drives ambient air across heat sinks, allowing full-load operation inside a sealed cabinet. The unit is rated for 15.0 kW of motor output, matching mid-sized production motors in packaging lines and material-handling systems. Line connection is through a 3 x AC converter front end, so it rectifies and inverts three-phase mains without external transformers. The permissible DC link is based on a supply window centered on 500 V, which is common to industrial 480 V networks.

To dissipate regenerated energy during rapid deceleration, a built-in brake chopper is present, routing excess DC voltage to an external resistor bank and preventing overvoltage trips. The hardware belongs to Design generation 1, which matches the first RD drive configuration. Control wiring is simplified by a NAMUR terminal strip with external 24 V standby power. This arrangement allows the control section to remain supplied independently of the main power stage. For diagnostic purposes, the drive exports phase current information through current filter feedback (U6, V6, W6), supporting oscilloscope checks and drive tuning.