Product Description:

The RAC 2.3-250-380-A0I-W1 is an AC main spindle drive controller manufactured by Bosch Rexroth Indramat as part of the RAC Spindle Drive Controllers series. Designed for large machining centers and other production equipment, it forms the closed-loop link between a CNC control and the main spindle motor, translating velocity setpoints into precisely modulated three-phase output. The device is intended for cabinet mounting, provides built-in cooling, and coordinates power conversion with feedback handling so that high-inertia spindles can accelerate, brake, and hold speed within the tolerances required for continuous multi-shift industrial automation.

The power stage is rated for 3 x AC 400 V, 50-60 Hz, allowing direct connection to standard plant mains without an intermediate transformer. At full load, the current path can deliver up to 250 A, giving sufficient headroom for cutting cycles that impose short-term torque peaks on the spindle. Control wiring is consolidated on connector X4 with 9 poles, so all logic lines are grouped on a single plug. The speed reference enters as an analog (+/-10 V) signal, which supports straightforward integration with legacy control schemes. Thermal energy is removed by an internal blower, so no external ductwork is required.

The controller retransmits spindle position through an incremental encoder output, enabling downstream axis synchronization without additional interface modules. For applications that manage braking energy through the machine's DC bus, the unit is supplied without an additional bleeder. Position monitoring based only on the primary encoder is reflected by delivery without an additional encoder input. The hardware build is identified as Version 3 and belongs to series 2. This version matches the RAC product generation used for that release.