Product Description:

The KDA 2.1-050-3-LQS-U1 is a spindle drive module from Bosch Rexroth Indramat in the KDA Spindle Drives series. It converts regulated DC power into controlled three-phase output for high-speed machine-tool spindles, enabling precise speed and torque regulation. The unit is used in multi-axis systems where quick acceleration, controlled deceleration, and repeatable surface finishes are essential. When paired with Indramat servo controllers, the drive forms the electrical link between the central CNC and the motor so commanded spindle profiles can be followed accurately.

The module is supplied from a common DC bus held at 300 VDC, and it can deliver up to 50 A of continuous output current to the connected spindle motor. Thermal energy is removed by an integral blower powered by a dedicated 115 V at 50/60 Hz single-phase feed, keeping the electronics within permissible temperature limits during sustained high-speed operation. Commanded speeds arrive digitally through the SERCOS interface, which gives the CNC deterministic control over acceleration ramps, overrides, and diagnostic feedback. A separate RS-232-C serial port provides direct parameter access without disturbing the real-time motion network. This forced cooling path is optimized for low impedance so the fan maintains constant airflow even when cabinet pressure fluctuates.

Air is directed across the power semiconductors before the exhaust reaches other cabinet components, helping maintain stable thermal conditions during extended operation. The drive is intended for shop floors maintained between 5 to 45 °C, so derating is unnecessary within that ambient range. Installation heights up to 1000 m above sea level are allowed without altering current limits, which supports consistent torque delivery in most manufacturing regions. As part of Series 2, the hardware uses a unified mechanical layout with consistent mounting holes, field wiring points, and address selection jumpers.