Product Description:

Bosch Rexroth Indramat manufactures the RD51.1-5B-007-D-DF-FW in the RD 500 Drive Controllers series. The unit functions as a three-phase converter that conditions incoming AC power and produces variable-frequency output for induction motors in automated cells, conveyors, and process equipment. By modulating voltage and frequency, it can match motor torque to load demands, reduce inrush current during startup, and support coordinated motion sequences under PLC supervision. This operating method makes the drive suitable for applications that need adjustable motor speed without a more complex feedback system.

The drive is rated for 7.5 kW, so its power section is sized for that continuous output when paired with a standard four-pole motor. It operates on 500 V mains and is supplied as a 3 x AC converter, which means the rectifier and inverter stages accept three-phase input directly without a transformer. Speed regulation uses U/f curve control, keeping a fixed voltage-to-frequency ratio so motor flux remains stable at low rpm. Heat from the power section is removed through a plug-through cooler for ratings up to 110 kW, which extends outside the enclosure and supports compact cabinet layouts. During deceleration, a built-in brake chopper diverts regenerated energy to an external resistor and helps prevent DC-bus overvoltage.

Field wiring is simplified by an integrated NAMUR terminal strip with external 24 V standby power, which keeps the control electronics active for diagnostics even when the main converter is isolated. Phase-related signals can be monitored through current filter feedback (U6, V6, W6), allowing external observation of filtered current values. The unit is in design generation 1, so it uses the earliest RD 500 parameter structure. Application-dependent control software is selected separately so the hardware can be matched to pump, conveyor, or similar drive tasks.