Product Description:

The RAC 3.5-150-460-A0I-Z1-220 is an AC main spindle drive controller produced by Bosch Rexroth Indramat for the RAC Spindle Drive Controllers series. In automated machining cells, it regulates spindle speed and torque by converting three-phase mains power into controlled motor voltage and current. This supports repeatable spindle operation in milling, drilling, and grinding equipment where stable speed must be maintained as cutting load changes during the process. Its role is to provide controlled motor power so the spindle can follow the commanded operating profile with consistent response.

For power distribution, the unit accepts 3 x AC 400 V or 3 x AC 460 V mains and can deliver a continuous line current of 150 A to the spindle motor. Excess regenerative energy is routed through an integrated circuit with an additional bleeder resistor, which helps prevent DC-bus overvoltage during rapid deceleration. Thermal exchange is handled by an internal blower, allowing cabinet mounting without external ductwork. The drive follows a ±10 V analog speed command through its differential input, and logic wiring is grouped on the X4, 9-pole terminal to keep field connections organized. The unit does not include an additional encoder input and relies on the primary feedback path already used by the drive.

The control section uses a separate AC 230 V control electronics feed, which keeps logic power isolated from the motor supply so diagnostic functions remain available during mains interruptions. A built-in incremental encoder output lets external controls monitor actual spindle position in real time for synchronized machine functions such as phase-related spindle actions. The unit is Version 5, and it belongs to series number 3 within the RAC platform. This version grouping marks the release level used for this spindle drive controller without changing its core function as a controlled spindle power stage.