Product Description:

The KDA 3.1-050-3-AQS-W1 spindle drive is manufactured by Bosch Rexroth Indramat for the KDA Spindle Drives series. Designed as a power stage between the DC bus and a motorized spindle, it receives velocity commands from the numerical controller and modulates three-phase output to maintain constant speed and torque during machining operations. This arrangement allows machine tools to synchronize spindle motion with axis feeds during drilling, milling, and grinding. It also supports stable spindle behavior when cutting conditions change during a machining cycle.

It works from a regulated link voltage of 300 VDC, matching the output of standard Indramat supply modules. The power section can deliver up to 50 A of continuous output current, so spindle windings can support demanding cutting loads without immediate thermal reduction. Speed reference enters the control electronics as an analog value, allowing smooth response when the CNC sends velocity ramps and gradual setpoint changes. Thermal energy is removed through forced cooling, and the fan draws its supply from 220 V/50–60 Hz so airflow can remain available independently of the DC link. This separate fan supply helps the unit maintain cooling even during abnormal operating conditions.

The mechanical layout uses a heatsink-mounted blower that channels air directly across the IGBT modules. This airflow supports operation within an ambient range of 5–45 °C and helps the power section manage heat during extended spindle duty. Installation is permitted up to 1000 m above sea level without output reduction, which suits production sites located at moderate elevation. For parameter access and diagnostics, the unit provides a serial interface (RS-232 C) so an external computer can communicate with the drive without removing it from the cabinet.