Product Description:

The KDA 3.1-150-3-DQS-U1 is a spindle drive manufactured by Bosch Rexroth Indramat as part of the KDA Spindle Drives series. Version 3 in the type code indicates the third design revision for this family. Positioned between a CNC controller and a high-speed spindle motor, the unit interprets numerical speed references and delivers controlled three-phase output so milling, drilling, and grinding processes can maintain repeatable surface finish, contour accuracy, and cycle time in automated production cells. It integrates with modular supply units inside an Indramat drive cabinet and shares the common DC bus used by multiple axes.

The drive is energized from a common DC bus at 300 VDC, a level that balances rapid energy exchange with manageable insulation stress. Under continuous duty, it can supply up to 150 A of armature current, allowing large-frame spindle motors to reach peak torque during heavy metal removal without derating. Spindle velocity is controlled by a 16-bit parallel digital command word, which provides 65,536 discrete setpoints that the internal regulator converts into sinusoidal output. For setup and process monitoring, the device includes an RS-232C serial interface that allows status reading and parameter adjustment. Thermal stability depends on an integral heat sink blower powered by a dedicated 115 V/50–60 Hz single-phase feed, which helps prevent hot spots around the IGBT modules.

The cooling assembly uses a mounted heat sink blower that directs air along the fin channels, and the unit relies on forced cooling to remove switching losses even when cabinet air is still. Continuous operation is specified for ambient temperatures from 5 to 45 °C, so additional panel ventilation is unnecessary within that range. Installation is permitted up to 1000 m above sea level, beyond which reduced air density can lower blower effectiveness and require current derating to keep semiconductor junction temperatures within safe limits.