Product Description:

Bosch Rexroth Indramat manufactures the KDA 2.1-100-3-LPI-U1 spindle drive as part of the KDA Spindle Drives series. This unit regulates the torque and speed of high-performance machine-tool spindles and provides closed-loop control for modular CNC drive cabinets. By converting a fixed DC bus into three-phase output, the drive delivers the fast and stable response needed for drilling, milling, and grinding operations where spindle behavior directly affects machining accuracy. Its control behavior is suited to applications that require quick speed changes without losing stability during continuous production cycles.

The power section operates from a DC link of 300 VDC and is rated for a continuous phase current of 100 A, so the connected motor can sustain demanding cutting loads without derating. A dedicated blower mounted on the heat sink uses an auxiliary supply of 115 V/50-60 Hz to move air across the power semiconductors. This mounted heat sink blower provides forced cooling, which helps keep semiconductor junction temperatures within safe limits during prolonged high-speed operation. In addition, the control board includes a second encoder input for spindle or auxiliary motor feedback, allowing high-resolution position data to be processed alongside the main drive loop.

The drive is intended for shop-floor installations rather than harsh outdoor locations. It operates at ambient temperatures from 5 to 45 degrees Celsius and at elevations up to 1000 m above sea level without output reduction. Velocity references arrive through the SERCOS interface, enabling deterministic communication with the motion controller. For diagnostic or synchronizing tasks, the front panel provides an incremental encoder output that mirrors spindle position in real time. This signal can be used by other control functions that need position tracking during coordinated machine motion.