Product Description:

The RD51.1-4N-022-L-DF-FW is a drive controller produced by Bosch Rexroth Indramat for the RD 500 Drive Controllers series. As a closed-loop power unit, it is installed in inverter cabinets to regulate induction motors in industrial automation lines. The controller matches commanded torque and speed to the available three-phase line supply, allowing the connected motor to run with stable output across typical process loads. Its role is focused on motor control rather than standalone machine logic, so it is used as part of a larger drive system.

This model is rated for 22 kW of continuous output and accepts line voltages from 380 to 480 V. The permitted input variation is ±10 %, which allows the converter to tolerate common supply fluctuations without reducing output. Because it is a 3 x AC converter, the unit rectifies all three incoming phases and reconstructs a variable AC output for the motor. It uses U/f curve control, which keeps the voltage-to-frequency relationship aligned with induction motor operation and works well in applications that do not require vector feedback. Current filter feedback is available on terminals U6, V6, and W6, allowing higher-level control equipment to monitor filter operation during use.

Thermal management relies on forced air cooling, so airflow must move from the bottom to the top heat sink area and cabinet fans must remain in service during operation. The unit is supplied without a built-in brake chopper, so regenerated energy from rapid deceleration must be handled by an external chopper or braking resistor. An integrated mains filter reduces conducted interference on shared power lines and supports cleaner installation in multi-drive cabinets. The control terminal block follows the NAMUR terminal strip format, and it can remain active from an external 24 V standby source when line power is isolated. This arrangement helps preserve communication and control availability during planned shutdown conditions.