Product Description:

The RD51.1-4N-005-L-C1-FW is a drive controller manufactured by Bosch Rexroth Indramat for the RD 500 Drive Controllers series. In automated production lines, this unit converts fixed mains power into variable frequency and voltage so standard AC induction motors can be started, stopped, and modulated precisely. By managing these motors, it supports conveyors, mixers, and pump stations that require reliable, repeatable speed control.

The controller accepts a three-phase input within 380 to 480 V and uses a converter 3 × AC topology that integrates rectifier and inverter sections. Motor output is rated at 5.5 kW, making the unit suitable for medium-duty machines and process equipment. Line fluctuations are tolerated up to ±10 %, which helps the drive remain stable when plant voltage shifts. Regulation is provided through U/f curve control, which keeps motor flux consistent by tracking the ratio of stator voltage to frequency. For electromagnetic compatibility, the housing contains an integrated mains filter, which reduces conducted interference on the incoming supply.

Thermal management relies on forced air cooling, so the installation must preserve a clear airflow path from the bottom intake to the top exhaust. Because the device is supplied without a built-in brake chopper, regenerative energy produced during rapid deceleration must be handled externally when system inertia is high. A dedicated control circuit delivers 24 V stand-by power, allowing the keypad, diagnostics, and fieldbus functions to remain active even when the main power section is not energized. This arrangement supports parameter access and status monitoring without requiring the motor output stage to be active.