Product Description:

The RAC 2.3-250-460-A00-W1 is an AC main spindle drive controller produced by Bosch Rexroth Indramat and assigned to the RAC Spindle Drive Controllers series. Designed for machine tools and other high-speed spindle applications, the unit converts three-phase mains power into regulated output for induction or synchronous spindles while enabling precise velocity control from the host CNC or PLC. By integrating current regulation, field weakening functions, and internal diagnostics, the controller supplies the torque and speed profile needed for constant surface-speed cutting and rapid acceleration in automated machining cells. This control behavior supports stable spindle response during tool engagement and other rapid changes in cutting load.

The input range is 3 × AC 400 V, 50 Hz, ±15%, or 3 × AC 460 V, allowing connection to European or North American factory networks without an external transformer. The power section can deliver a continuous line current of 250 A, which suits large spindle motors that draw high current during acceleration. Thermal management relies on a built-in fan that forces air through the heat sink instead of requiring cabinet ducting. Speed reference is accepted as an analog (±10 V) signal for closed-loop regulation. Field wiring lands on the X4 9-pole terminal strip, which groups enable, fault, and reference lines in one connector. This arrangement keeps external control wiring organized around the standard command and status connections.

The drive is supplied without an additional bleeder, so excess regenerative energy must be handled by the DC bus or an external resistor assembly. It is also supplied without an additional encoder input, so the primary spindle feedback channel uses only the standard interface. The unit is Series 2 and Version 3. Those identifiers place the controller in the second RAC generation with the third control revision used for this model.