Product Description:

The RAC 3.5-100-460-A0D-W1-220 is an AC main spindle drive controller produced by Bosch Rexroth Indramat for machine tool applications and belongs to the RAC Spindle Drive Controllers series. It is Version 5 in Series 3, and it conditions high-power three-phase line power before delivering regulated output to a spindle motor. This allows cutting speed to remain stable during load changes in demanding machining processes. It is intended for spindle systems that require precise speed control during drilling, milling, and similar metalworking operations. By combining the power stage and control electronics in one chassis, the unit supports compact cabinet layouts in automated machining centers.

The controller has a rated current of 100 A, allowing it to respond to rapid torque changes without saturation. It accepts a mains supply of up to 3 x AC 460 V at 50 Hz with a tolerance of ±15%, which covers common North American and European supply levels. Thermal management is provided by an internal blower, so no external ducting is required. Velocity commands are entered through an analog ±10 V input, which gives the spindle control loop a standard analog reference. Status and low-level control lines are grouped on the X4 nine-pole connector, which helps keep field wiring organized inside the panel.

For position-based tasks, the controller also accepts a 16-bit parallel digital position setpoint, allowing a CNC to send absolute spindle angles directly. The unit is supplied without an additional bleeder, so braking energy must be handled by the motor or by upstream electronics. It also comes without an additional encoder input, leaving feedback processing to the primary spindle resolver line. The control boards draw service power from an auxiliary supply of AC 230 V / 50-60 Hz. A separate service supply helps isolate low-level electronics from disturbances on the high-power bus during operation.