Product Description:

Bosch Rexroth Indramat built the KDA 2.1-150-3-A0D-U1 as part of the KDA Spindle Drives series. This version 2 module serves as a power converter that delivers controlled three-phase energy to high-speed machining spindles during cutting, drilling, and grinding cycles in automated machine tools. By processing command signals from a numerical controller and supplying the spindle motor with regulated current, the unit supports repeatable acceleration profiles and stable speed control during changing cutting loads. It is intended for spindle service where rapid response and consistent rotation help maintain predictable machining behavior and surface finish.

The unit draws its intermediate circuit energy from a 300 VDC supply, and its output path can deliver up to 150 A of continuous armature current, enabling large-frame spindle motors to operate without derating. Thermal stability is maintained by an attached heat sink that is cooled by a blower powered from an auxiliary line of 115 V/50–60 Hz, which removes losses directly at the power stage rather than relying on cabinet air circulation. The drive uses forced cooling, so airflow is controlled by the electronics to keep semiconductor temperatures within safe limits when load demand changes sharply. This arrangement supports sustained spindle operation during demanding machining cycles and helps maintain stable switching behavior in the power section.

The drive operates in ambient air from 5 °C to 45 °C and may be installed up to 1000 m above sea level without adjustment to its current limit. Speed is set through an analog speed command value, while position trimming can arrive through a digital position command value interface, allowing the control system to separate speed regulation from positional correction. The lack of a secondary encoder input keeps feedback wiring minimal and reduces interface complexity at the drive. The mounted heat sink blower continues ventilation whenever internal sensors detect a rise in module temperature.