Product Description:

The KDA 3.1-100-3-API-W1 is a spindle drive module produced by Bosch Rexroth Indramat and supplied in the KDA Spindle Drives series. Designed for Series 3 hardware, the drive converts a stabilized DC link voltage into controlled three-phase power for machine-tool spindles with precise speed regulation. In automated machining centers, the unit serves as the interface between the CNC control and the high-speed motor, enabling real-time speed changes, torque regulation, and braking functions during drilling, milling, and grinding cycles. This arrangement allows the spindle to respond quickly to changing load conditions and commanded speed setpoints.

The drive operates from a 300 VDC DC bus and can deliver a continuous phase output of 100 A, allowing high-torque acceleration of large spindle masses. Thermal management is handled by a mounted heat-sink blower that directs airflow across the transistor modules, and the blower is powered from an auxiliary line of 220 V/50-60 Hz. Because the internal components generate significant switching losses during rapid speed changes, the unit relies on forced cooling to keep semiconductor temperatures within safe limits. Independent blower operation also helps maintain airflow when spindle speed is low and heat generation remains high.

The drive accepts an external speed command as an analog voltage or current reference, and it offers an incremental encoder output so the CNC can monitor actual spindle position without additional splitters. A second encoder input is available for spindle feedback or auxiliary motor feedback, which supports synchronous tapping and orientation routines. Ambient operating conditions range from 5 to 45 °C, and performance remains unchanged up to 1000 m above sea level. Outside these limits, additional airflow or voltage margin may be required.