Product Description:

The RAC 2.3-200-460-AP0-W1 is an AC main spindle drive controller produced by Bosch Rexroth Indramat for the RAC Spindle Drive Controllers series. It regulates high-power spindle motors in machine tools, supporting closed-loop speed control and coordinated motion within larger CNC systems. By receiving velocity references from the machine control, the unit modulates three-phase motor power while monitoring spindle feedback through a dedicated encoder channel. This arrangement helps the drive respond to changing cutting loads and maintain stable spindle behavior during machining and orientation tasks.

This controller accepts a three-phase supply of 3 × AC 400 V ±15% or 3 × AC 460 V and can deliver up to 200 A of output current, allowing direct connection to large asynchronous or synchronous spindles. Thermal energy generated by switching losses is removed by an internal blower, so heat is carried away from the power section without external cooling hardware. The speed reference uses an analog (+/-10 V) command, and field wiring for control signals is grouped on the 9-pole X4 terminal strip. Keeping low-level I/O separate from the power section helps limit electrical noise on command and feedback circuits, and it also supports cleaner cable routing inside the control cabinet.

During regenerative operation, the controller is supplied without an additional bleeder, so braking energy is absorbed by the DC bus unless an external braking unit is added. It also includes an additional encoder input for spindle feedback, which allows the CNC to exchange position data for synchronized spindle functions such as orientation and rigid tapping. The feedback path works with a high-resolution INDRAMAT encoder, helping the drive hold smooth low-speed operation and accurate phase alignment. That behavior is useful when the spindle must stop at a known angle before tool handling or thread-cutting cycles begin. The controller is part of Series 2, and the product is Version 3.