Product Description:

The KDA 2.1-050-3-API-U1 spindle drive is produced by Bosch Rexroth Indramat within the KDA Spindle Drives series. As a Series 2 unit, it controls asynchronous or synchronous spindles in milling centers and lathes through a closed-loop architecture connected to encoder feedback. The drive supplies regulated three-phase energy from a shared DC bus while maintaining commanded spindle speed during cutting, drilling, or turning operations. Encoder feedback lets the control loop compare actual spindle motion with the commanded value, which helps the system correct speed changes caused by varying chip load or tool engagement.

Power for the drive section is taken from a DC link rated at 300 VDC, and the converter can deliver a continuous phase current of 50 A to the spindle motor. Thermal management relies on a mounted heat sink blower powered by a dedicated 115 V/50–60 Hz source, which forces air across the fins to remove switching losses from the power stage. Safe operation is permitted within an ambient range of 5 to 45 °C, allowing installation in typical machine enclosures without separate refrigeration equipment. This cooling arrangement supports continuous spindle duty where sustained current and switching activity generate steady internal heat.

The KDA 2.1 design supports motion feedback and command integration through a dedicated incremental encoder output that passes position information to a master controller. A second encoder input is available for spindle or auxiliary motor feedback when additional feedback channels are needed, and the speed reference enters the drive as an analog speed command value. The analog reference path suits control systems that issue a voltage-based speed request rather than a network command. Installation is permitted up to 1000 m above sea level without derating, so the unit can be used in standard industrial locations at moderate elevation.