Product Description:

The RAC3.1-150-460-L00-W1-220 is an AC main spindle drive controller from Bosch Rexroth Indramat and belongs to the RAC Spindle Drive Controllers series. It governs high-speed spindle motors in machining centers by converting fixed mains energy into variable, feedback-regulated power that follows a digital speed command. Within an automation line, the unit closes the velocity loop for the spindle axis and interfaces with upper-level CNC hardware, allowing precise cutting speeds and controlled braking without the mechanical losses of belt transmissions. This arrangement helps maintain stable spindle response when cutting loads change during machining.

In continuous operation, the controller can deliver 92 A of armature current, translating to a sustained mechanical output of 35 kW at the motor terminals, while its DC link can absorb 27 kW of regenerative energy. The internal logic and gate drivers draw only 200 VA and are supplied through a separate 220 V AC auxiliary feed, so the main power stage can be isolated when needed. The controller belongs to the 150 A current category. Speed commands arrive over the SERCOS fiber-optic link, and no additional encoder input, bleeder, or user interface slots are present, which simplifies wiring and keeps heat density predictable inside the cabinet.

Thermal management is handled by a built-in fan, allowing full output up to an installation altitude of 1000 m without derating. During short surges, the inverter supplies up to 40 kW in both motoring and regenerative modes, with braking energy returned to the DC bus rather than dissipated externally. The steel enclosure has an IP10 rating, so it must be mounted inside a clean electrical cabinet, and the shipping mass of 49 kg should be considered when planning panel reinforcement. Because no auxiliary interface cards occupy the backplane, service access remains clear and the cooling path stays unobstructed.