Product Description:

The KDA 2.1-150-3-AQS-U1 spindle drive is produced by Bosch Rexroth Indramat for the KDA Spindle Drives series. Installed between the DC bus and a high-speed spindle motor, it converts supplied energy into controlled three-phase output so machining centers can hold constant surface speed and maintain process accuracy in automated production cells. It is part of generation 2 in the series and is used in milling, drilling, and grinding systems that require rapid acceleration, stable speed regulation, and smooth deceleration under numeric control, where spindle response affects both surface finish and cycle consistency.

Electrical power enters the drive at 300 VDC, and its output stage can deliver a continuous 150 A to the spindle, allowing demanding cutting cycles without voltage sag. Speed reference signals are accepted as analog levels, matching standard CNC control cards and supporting direct integration with common spindle command circuits. Thermal management relies on a heat sink blower that draws ambient air across the fins, and the unit uses forced cooling to keep semiconductor temperatures within limits during extended machining passes and repeated load changes. The blower is powered by a separate 115 V / 50–60 Hz auxiliary supply, so cooling can continue independently of the DC bus after spindle motion is reduced or stopped.

The unit operates in ambient temperatures from 5 to 45 °C, which suits typical indoor industrial environments and enclosed machine installations. Full output is maintained up to 1000 m above sea level, allowing use in most standard plant locations without derating. A front-panel RS-232C serial interface is available for parameter upload and error logging. This connection provides a direct local communication path for reading drive status data and reviewing stored fault information when operating values need to be checked.