Product Description:

The KDA 3.1-150-3-APD-U1 is manufactured by Bosch Rexroth Indramat as part of the KDA Spindle Drives series. It functions as a dedicated spindle controller that draws energy from a common DC bus and modulates that power into three-phase output for fast machining spindles. By integrating speed and position feedback channels, the drive supports precise acceleration, deceleration, and holding behavior required in automated milling or grinding equipment. It is intended for machine platforms where spindle speed stability and repeatable orientation are both required.

The drive’s power stage is supplied from a 300 VDC intermediate circuit and can deliver a continuous output of 150 A to the connected motor windings. A separate auxiliary line rated at 115 V at 50/60 Hz feeds the heat sink fan, keeping semiconductor temperatures within safe operating limits. Thermal management relies on forced cooling, and motion commands are accepted as an analog speed command value that can be scaled to match different process ranges. The unit is series 3, and this release adds improved gate control and diagnostic routines. This control method supports spindle applications that need direct speed reference input from a machine controller and quick response to changing load conditions.

An integrated mounted heat sink blower concentrates airflow directly across the power transistors, which helps preserve rated current across the ambient range of 5 to 45 °C. Installations are permitted up to 1000 m above sea level without derating. Control architecture is expanded by a digital position command value interface for coarse spindle positioning, and a second encoder input can accept either true spindle feedback or an auxiliary motor encoder for tandem applications. The extra encoder option supports spindle systems that use a motor-mounted feedback device in addition to the main spindle sensor. That added input path is useful when the machine separates spindle position measurement from motor commutation feedback.