Product Description:

The RAC2.1-150-380-A00-W1 is an AC main spindle drive controller manufactured by Bosch Rexroth Indramat within the RAC Spindle Drive Controllers series. Designed for use with 2AD and 1MB spindle motors, it conditions three-phase line power and executes velocity control so production spindles track programmed speed profiles during machining, grinding, or drilling tasks. Housed for cabinet mounting, the unit brings together power conversion, motion regulation, and built-in safety functions needed for tightly coupled industrial automation axes.

The controller operates from a rated 3 x AC 400 V mains supply that can be wired directly, eliminating the need for isolation transformers in most installations. Thermal stability is maintained by a built-in fan that forces air over the heat sink to hold current capacity across the entire duty cycle. If supply loss occurs, the drive initiates direct current braking, injecting DC into the motor windings so rotational energy is absorbed electrodynamically and the spindle stops quickly. When commanded deceleration creates surplus power, mains regeneration channels that energy back to the utility instead of heating external resistors. Spindle velocity is commanded through an analog ±10 V reference, and the internal converter samples this signal to generate a proportional digital setpoint for real-time speed regulation.

Feedback resolution reaches 1/4,000,000 of a revolution, enabling fine torque modulation for surface-finish-sensitive operations even at high RPM. An auxiliary supply provides 24 VDC at 1 A to field sensors or control relays, simplifying peripheral wiring. System signals such as ready, fault, enable, and limit inputs terminate on a 37-pole control I/O plug, while resolver or encoder leads return through a dedicated 15-pole motor-feedback connector. Direct three-phase mains entry, an integrated emergency-stop link, and the absence of additional interfaces or bleeder assemblies help keep the cabinet layout compact.