Product Description:

The KDA 3.1-150-3-AQD-U1 spindle drive is manufactured by Bosch Rexroth Indramat as part of the KDA Spindle Drives series. It serves as the power and control module for machine-tool spindles, delivering regulated three-phase output from a shared DC bus. Within automated machining centers, the drive enables programmable acceleration, deceleration, and holding speeds so cutting heads achieve the commanded surface velocity without mechanical gear changes. This operating role supports spindle applications that need repeatable speed changes during drilling, milling, and indexing tasks.

The power stage operates from a 300 VDC intermediate circuit, giving the inverter sufficient voltage overhead for rapid spindle ramps. A continuous output capability of 150 A lets the drive supply high electromagnetic torque without crossing current-limit thresholds. Thermal management depends on a 115 V/50-60 Hz auxiliary feed that energizes the cooling fan. That fan is arranged as a heat sink-mounted blower, pushing airflow directly across the power semiconductors. Because the airflow is active rather than natural, the unit uses forced cooling to hold device temperatures within operating limits during extended duty cycles. Safe use is specified for ambient temperatures from 5 to 45 °C, so cabinet ventilation must keep inlet air within this range.

Installation height is limited to 1000 m above sea level; beyond that point, derating would be required because thinner air reduces cooling effectiveness. The velocity loop accepts an analog speed command value, while a digital position command value channel allows a numerical controller to send absolute angle targets for indexing operations. This combination supports both continuous spindle speed regulation and commanded orientation when the machine needs angular positioning. The interface arrangement allows direct connection to machining-center control systems without external signal converters or added airflow devices.