Product Description:

The RD52.1-8N-090-L-LV-FW drive controller is produced by Bosch Rexroth Indramat as part of the RD 500 Drive Controllers series. It regulates AC machines in closed-loop operation, converting high-voltage DC link energy into programmable three-phase output so that speed and torque follow digital setpoints from a supervisory control system. In automated conveyors, machining centers, and process lines, the unit delivers vector-based current control to support stable axis performance. Its housing and connector layout are intended for switch-cabinet installation alongside contactors and protective components.

This controller uses field-oriented vector control, so stator flux is calculated in real time to separate torque-producing current from magnetizing current. Thermal management is handled by forced-air cooling, and airflow through the heat sink helps maintain acceptable semiconductor temperatures during continuous high-load operation. The power section uses a DC link of 700 V and is classified as an Inverter DC supply type, so it must be paired with an external rectifier or a common DC bus. Nominal mechanical output reaches 90 kW, which suits demanding loads such as large pumps or extruders. The unit is design 1, which indicates the first hardware release.

The drive has no built-in brake chopper, so applications that return regenerative energy require external chopper hardware. Diagnostic monitoring includes cable damping feedback (C3, D3), which helps detect transmission-line resonance that could stress the drive transistors. For logic retention during mains loss, the control circuit accepts external 24 V standby power, allowing parameter memory and fieldbus nodes to remain active. This arrangement helps the controller preserve its control state while the main supply is unavailable.