Product Description:

The KDA 3.2-050-3-AP0-W1 spindle drive is produced by Bosch Rexroth Indramat as part of the KDA Spindle Drives series. Serving as a servo inverter for machine-tool spindles, it converts the shared DC bus energy of an Indramat power supply into the controlled three-phase output required to turn high-speed spindle motors. Within an automated cell, the unit regulates torque and velocity so that cutting, grinding, or drilling operations stay within programmed profiles and surface-finish limits. This control behavior helps the spindle respond to changing cutting loads without drifting from the commanded speed. It is intended for installations where spindle speed regulation must remain consistent across rapid acceleration, load changes, and deceleration.

The internal power stage is energized from a 300 VDC link, and its transistors are sized for a continuous output of 50 A, enabling medium-power spindles to accelerate quickly without current foldback. Thermal management relies on an auxiliary blower fed from 220 V 50/60 Hz, so airflow remains stable during regenerative events. Cooling air is provided by a rear-mounted heat sink blower on the back of the housing. The drive uses forced cooling to keep the heat sink below its derating threshold during long contouring cycles. Stable airflow also supports continuous spindle operation during extended machining passes.

The drive maintains full ratings from 5 to 45 °C, and altitude can reach 1000 m above sea level before additional cooling is required. For position-synchronized work such as rigid tapping, a second encoder input lets the controller process spindle feedback in parallel with an auxiliary motor sensor. Command data reaches the analog velocity input through an analog speed command interface, which suits retrofit systems that already distribute ±10 V setpoints from the CNC. No additional option boards are fitted, so the unit retains its standard control configuration.