Product Description:

The RD51.2-4B-003-L-NN-FW is manufactured by Bosch Rexroth Indramat and belongs to the RD 500 Drive Controllers series. It is intended to regulate induction motors in plant machinery by converting fixed-frequency three-phase mains power into a variable output for speed and torque control. This operating method lets the drive adapt motor behavior to changing process demands instead of running at only one fixed speed. It is well suited for automated equipment that needs stable acceleration, adjustable throughput, and repeatable motor response during routine production changes.

The unit is Design Generation 2. Motor excitation is handled through U/f curve control, so voltage follows frequency along a preset ratio that helps maintain magnetic flux under changing load. This control method is commonly used where dependable speed adjustment is needed without the complexity of more advanced motor models. A built-in brake chopper dissipates regenerated energy during deceleration and helps protect the DC link. Thermal management relies on forced air cooling, so a clear cabinet airflow path is required to remove switching losses at nominal current. To reduce conducted emissions at the input stage, the drive includes an integrated mains filter that limits high-frequency noise on the facility supply.

Electrical capability reaches 3.0 kW of output, which suits medium-frame motors used on pumps, fans, and material-handling axes. The power section is fed from a 3 × AC converter supply and accepts line-to-line voltage within a range of 380 to 480 V. Component tolerances allow input fluctuations of ±10 % without derating, which gives the unit tolerance for common undervoltage and overvoltage conditions in industrial installations. The specified input window works with an internal rectifier and intermediate DC link sized for this power class and supports operation on widely used plant power systems.