Product Description:

Bosch Rexroth Indramat manufactures the KDA 3.2-100-3-APD-U1, a spindle drive in the KDA Spindle Drives series. Classified as Series 3, Version 2, it energizes high-speed machining spindles by converting a regulated DC bus into a three-phase output that follows numerical control references. Within automated machining cells, this function allows precise tool speed regulation, rapid acceleration, and controlled deceleration without overshoot.

The power stage is supplied from a 300 VDC intermediate circuit and can deliver a continuous output of 100 A, enabling it to energize large frameless motors without derating. Thermal energy is removed through a mounted heatsink blower, and the fan operates from an auxiliary line of 115 V at 50–60 Hz, so the spindle channel remains ventilated even when the main bus is disabled. This cooling method uses forced cooling, which means airflow is actively moved across the fin stack instead of relying on natural convection. The arrangement keeps semiconductor junction temperatures within limits during long rough-cut passes and helps reduce heat buildup in nearby components.

The operating range allows use between 5 to 45 °C, and installation is permitted up to 1000 m above sea level without current reduction, fitting typical shop-floor conditions. Speed reference signals are accepted as an analog speed command, while contouring accuracy can be improved by feeding a digital position command through the additional interface. A second encoder input is available for spindle feedback or an auxiliary motor sensor, letting the controller compare multiple measurement sources when rigid tapping or synchronous milling is required. This added feedback path supports applications that need coordinated spindle motion and closely monitored speed behavior.