Product Description:

The KDA 3.3-050-3-AP0-W1 belongs to the KDA Spindle Drives series produced by Bosch Rexroth Indramat. It serves as the intermediary between the DC bus of an Indramat supply module and the three-phase stator of a machine-tool spindle motor, delivering regulated torque and speed for milling, turning, or grinding processes. By integrating with CNC controllers, the drive helps maintain precise spindle velocity profiles needed for repeatable chip-forming and finishing tasks.

Internally, the drive’s heat sink is cooled by a blower that operates from a separate 220 V AC supply rated for 50–60 Hz service. The fan is mounted directly on the rear plate, providing a mounted heat sink blower arrangement that helps prevent power transistor overheating during continuous duty. Thermal energy generated in the switching stages is further managed by the unit’s forced cooling design, which supports full output at a DC bus of 300 VDC. Under these electrical conditions, the current regulators are tuned to supply up to 50 A of phase current, matching the demands of medium-frame asynchronous or synchronous spindle motors without saturating the IGBTs.

In field installation, the housing may be placed in shops where the ambient air remains within 5 to 45 °C, ensuring that airflow from the integral fan keeps semiconductor junctions below their design limits. Operation is permitted up to 1000 m above sea level without derating, so the same cabinet layout can be used in most industrial regions. The controller accepts an analog speed command, which is filtered and scaled internally before reaching the vector control loop. For position-sensitive tasks, a second encoder input is provided to return spindle or auxiliary motor feedback. Hardware release 3 comes without an additional interface option, so wiring is limited to the standard power, command, and feedback connections used for this drive family.