Product Description:

The KDA 2.1-050-3-AYI-W1 is a digitally regulated spindle drive produced by Bosch Rexroth Indramat for the KDA Spindle Drives series. In computer numerical control machine tools, it converts bus power into controlled three-phase output for high-speed motor spindles, allowing precise speed and torque regulation during metal cutting, drilling, and grinding. The unit exchanges speed references with the master controller and provides encoder feedback, so it serves as the motion-axis interface between the power bus and the mechanical spindle shaft. This supports spindle applications where speed must change quickly while the control loop maintains stable torque behavior.

Internally, the drive is energized by a DC bus of 300 VDC and can deliver a continuous output of 50 A to the connected spindle motor. A separate blower input rated at 220 V/50-60 Hz supplies the heat sink fan, and the drive uses design version 2 hardware. Speed reference arrives as an analog command, which the controller scales to its internal current loop for rapid torque response. This arrangement separates the fan supply from the main power stage and helps maintain thermal stability during sustained spindle operation. When an application needs redundant position data, a second encoder socket accepts both a synchronous track and a differential incremental channel in addition to the standard incremental output used by downstream numerical control modules.

The drive operates in ambient air from 5 to 45 °C and at elevations up to 1000 m above sea level. Cooling is provided by a mounted heat sink blower, and the method is classified as Forced Cooling, which allows continuous operation at rated current by moving air across the power semiconductors. Motion feedback can also be routed to external monitoring devices through the built-in incremental encoder output, while the second encoder input maintains closed-loop accuracy during spindle operation. The available encoder signals allow external controls to observe spindle behavior without interrupting the primary feedback path.