Product Description:

The KDA 2.1-100-3-AQI-U1 spindle drive is produced by Bosch Rexroth Indramat for the KDA Spindle Drives series. It converts DC bus energy into three-phase spindle power while accepting speed references from a numerical controller, making it suitable for metal-cutting, grinding, and drilling centers. By combining current regulation with position feedback, the drive keeps spindle acceleration predictable and helps maintain stable spindle behavior during changing cutting loads. This operating approach supports repeatable surface quality and consistent machine response in automated machining lines.

This model delivers a continuous motor phase current of 100 A, allowing it to energize large-frame high-frequency spindles without saturation. Its intermediate circuit operates at 300 VDC, so the unit must be paired with a compatible supply module that maintains that bus level. Thermal management relies on forced cooling, and air is pulled across a finned heat sink by a mounted heat sink blower to remove loss heat generated by the IGBT bridge. The speed reference enters the drive as an analog command value, and the internal regulator converts that input into current setpoints for precise velocity control during dynamic load changes.

The heat sink blower is powered from an auxiliary line rated at 115 V/50-60 Hz, so control power does not need to be drawn from the DC link. Position feedback can be daisy-chained to external motion controllers through an incremental encoder output, enabling synchronized axis coordination in multi-axis machine layouts. For reliable operation, the housing must be installed where ambient air stays within 5 to 45 °C, and the cabinet height cannot exceed 1000 m above sea level to preserve cooling performance. Adequate cabinet airflow helps the blower carry heat away from the power section during continuous duty.