Product Description:

The RD52.1-8N-400-R-M1-FW is a drive controller produced by Bosch Rexroth Indramat for the RD 500 Drive Controllers series. It sits between a DC bus and a three-phase motor to adjust frequency and voltage for automation tasks that demand high power. By controlling the stator field, it supports coordinated motion, reduced mechanical stress during startup, and stable speed regulation in systems such as assembly lines, pumps, and rolling mills. This makes it suitable for processes that need controlled acceleration and repeatable speed under changing loads.

This model delivers 400 kW of output, so it can run high-power motors without parallel drives. The intermediate circuit accepts up to 700 V DC, giving the inverter headroom during regenerative events and normal supply variation. Torque control is handled through field-oriented vector control, which separates flux and torque components for fast response during load changes and varying process conditions. That control method also improves low-speed behavior in demanding torque applications. Thermal management relies on liquid cooling with an internal pump, which removes heat directly from the power modules and supports compact cabinet layouts. The DC link is fed from an inverter DC source, so the controller can operate on a common bus with compatible front-end modules or neighboring drives.

The unit is supplied without built-in brake chopper, so external braking hardware is needed when rapid deceleration returns excess energy to the DC bus. It also comes without output chokes, which keeps the package smaller but makes proper motor-cable routing and EMC practice more important. The hardware is part of design generation 1, which matches the first-generation RD 500 option platform. The base unit is delivered with firmware ordered as a separate subposition, so the operating software is selected independently of the power section. The absence of these onboard additions leaves braking and output conditioning to external system components.