Product Description:

The RD51.1-5B-110-L-V1-FW is a drive controller manufactured by Bosch Rexroth Indramat for the RD 500 Drive Controllers series. In an automation cell, this unit supplies adjustable three-phase power to induction motors so that conveyor speed, pump flow, or fan output can be matched to process demand rather than fixed line frequency. By modulating voltage and frequency, the controller serves as the interface between higher-level PLC logic and the mechanical load. This operating method supports smoother starts and speed changes than direct across-the-line motor operation.

This model delivers a rated output of 110 kW, allowing it to operate large motors in heavy-duty applications. The DC link is fed from a mains window of 500 V, and the input stage uses a Converter 3 x AC design, so it connects directly to a three-phase utility supply. Motor excitation is managed with U/f curve control, a scalar method that helps maintain magnetic flux at low speeds for steady torque response. This control approach is well suited to standard induction motors used in pumps, fans, and conveyor systems. All internal heat is removed by forced air cooling, so the airflow openings must remain unobstructed during operation.

During rapid deceleration or overhauling loads, excess energy is absorbed by the integrated built-in brake chopper, eliminating the need for an external dynamic-braking module. Control electronics can remain active when the main power section is off because the unit accepts external 24 V standby power. This keeps communication and diagnostic functions available while the main input is disconnected. The hardware is part of Design Generation 1, which places it within the first RD500 design release. The controller also requires a separately ordered software package so it can perform the intended control function.