Product Description:

Bosch Rexroth Indramat manufactures the KDA 2.1-150-3-LYI-U1 spindle drive within the KDA Spindle Drives series. Intended for machine tool applications, the device synthesizes variable three-phase outputs from a shared DC link so that motor-mounted sensors and CNC controllers can coordinate spindle speed, torque, and orientation. Version 2 supports both primary and auxiliary encoder channels, giving machining equipment the feedback density needed for synchronized tapping, contour milling, and other precision processes. This arrangement lets the spindle perform speed-regulated cutting, commanded orientation at standstill, and coordinated motion with feed axes during machining cycles.

The drive accepts a DC bus of 300 VDC, and its power electronics are rated to deliver a continuous phase current of 150 A to the connected spindle motor. Thermal stress from this load is removed through forced cooling, and the airflow is provided by a mounted heat sink blower fixed directly to the backplane. Because the blower is mounted on the backplane, cooling air is directed across the finned surface instead of relying only on passive cabinet circulation. A second encoder input with synchronous timing allows the control loop to compare rotor position from two sources, which helps reduce interpolation error during rapid acceleration and precise orientation moves.

The blower is powered by a separate supply of 115 V at 50/60 Hz, which keeps fan demand isolated from the main bus. Reliable operation is permitted from 5 °C to 45 °C, and the unit can be used up to 1000 m above sea level without derating. Speed reference data reaches the drive through the SERCOS interface, while position verification can be routed outward through an incremental encoder output for external monitoring or coordinated machine functions. The outward encoder signal can also be used by control hardware that requires a replicated position signal for synchronization.