Product Description:

The KDA 2.1-100-3-DPI-U1 spindle drive is manufactured by Bosch Rexroth Indramat as part of the KDA Spindle Drives series and belongs to the electrically updated Series 2. Designed to sit between a CNC controller and a high-speed spindle motor, it converts command data into controlled three-phase output so cutting tools maintain programmed surface speeds. By modulating current in real time, the module supports torque linearity and position repeatability during repetitive machining cycles. This arrangement helps the spindle maintain stable speed during changing cutting loads and rapid transitions between machining steps.

The drive draws its intermediate-circuit power from a 300 VDC supply, and the internal power section is rated to deliver 100 A without derating, giving it the thermal capacity needed for heavy roughing passes. Heat is removed by forced cooling, and the dedicated heat sink blower is energized by a single-phase 115 V/50–60 Hz source so enclosure temperature stays within limits even at low spindle speeds where natural airflow is minimal. Motion commands reach the power electronics as a 16-bit parallel digital word, allowing the controller to request discrete speed values with fine low-speed resolution during tapping or thread cutting. That command format gives the upstream control a direct way to transmit speed references without relying on an analog interface.

Complementary diagnostic data leave the module through an incremental encoder output, while a second encoder input accepts spindle or auxiliary motor feedback to close an additional control loop when multitasking heads are installed. This signal path supports monitoring functions and coordinated operation with secondary spindle functions. Airflow is directed across the fins by the integral mounted heat sink blower, so no external ducting is required. Reliable operation is specified between 5 to 45 °C, and performance remains unaffected up to 1000 m above sea level; above that altitude, derating is advised. Series-standard protective circuits support use in machining centers and automated transfer lines.