Product Description:

The KDA 3.2-050-3-D0I-W1 is a spindle drive unit produced by Bosch Rexroth Indramat within the KDA Spindle Drives series. In automated machining centers, the drive regulates three-phase spindle motors, supplying the commanded speed and torque profiles required for milling, drilling, or grinding operations. By converting a regulated DC-link voltage into a controlled three-phase output, it acts as the intermediate power stage between the machine controller and the mechanical spindle. This allows the CNC to manage spindle acceleration, deceleration, and steady running through the drive rather than controlling the motor directly.

The drive draws its main power from a DC bus rated at 300 VDC, and this constant voltage rail allows multiple axes to share regenerated energy across the cabinet. During continuous duty, the power electronics can deliver a spindle phase current of 50 A, supporting sustained cutting loads during normal operation. An integral heatsink is cooled by a blower supplied from an auxiliary AC feed of 220 V/50–60 Hz. Because the fan is mounted directly on the heatsink, the unit uses a heatsink-mounted blower to keep the IGBT junction temperature within limits. The cooling path uses forced cooling, meaning ambient air is pushed across the fins instead of relying on natural convection.

To operate reliably, the unit must be installed where the ambient temperature stays between 5 to 45 °C and where the site elevation does not exceed 1000 m above sea level. Speed commands reach the drive through a 16-bit parallel interface, so the spindle controller receives 65,536 discrete speed references without needing analog conversion. For position-referenced spindle orientation, the drive provides an incremental encoder output and omits a second encoder input when only one feedback channel is required. This arrangement supports orientation tasks such as tool changing or fixed-angle spindle stopping, while motion profile generation remains with the machine's CNC.