Product Description:

The KDA 2.1-100-3-DQD-U1 is a spindle drive module produced by Bosch Rexroth Indramat and supplied within the KDA Spindle Drives series. As a dedicated spindle controller, it converts the constant DC link power from an Indramat supply unit into variable three-phase output for high-speed induction or synchronous spindles used in metal-cutting centers, grinders, and other precision automation equipment. It integrates power electronics and real-time interface circuits so CNC systems can command torque and speed directly, allowing rigid tapping, contour milling, and other machining tasks that depend on coordinated axis movement. The module is intended for closed-loop spindle applications where stable speed control and fast response are required during acceleration, deceleration, and spindle orientation.

Internally, the drive operates from a bus voltage of 300 V DC, drawing and regulating up to 100 A of continuous output current for the spindle windings. Thermal management relies on a mounted heatsink blower that channels air across the IGBT stack, and the blower itself is energized from a separate 115 V AC 50–60 Hz source so it can continue running even when the main bus is disabled. This airflow is part of the drive’s overall forced cooling method, which helps keep semiconductor temperatures within a safe operating range during heavy cutting loads or extended run times. Using a separate blower supply also helps remove residual heat after the spindle has been stopped.

The unit is intended for ambient temperatures between 5 to 45 °C, and it maintains full output up to 1000 m above sea level without derating. Command processing uses a digital position command value interface for precise spindle orientation, while rotational velocity is accepted as a digital 16-bit parallel speed command to reduce delay inside the numerical control. These control paths support accurate spindle alignment during tool changes and stable speed regulation during machining cycles. The arrangement also allows the CNC to transmit motion requests directly to the drive with minimal intermediate conversion.