Product Description:

The KDA 3.1-100-3-APS-U1 is a spindle drive from Bosch Rexroth Indramat and belongs to the KDA Spindle Drives series. It regulates three-phase induction or synchronous spindle motors in metal-cutting and high-speed machining centers, converting a fixed DC bus into a variable, precisely metered armature output so that the spindle can accelerate, hold speed, and decelerate under numerical control. This allows the machine control to maintain stable spindle speed during cutting loads and programmed speed changes.

The power stage is energized by 300 VDC from the shared supply module, and its current limit is 100 A, allowing the drive to start large-inertia spindles without stalling. Thermal management relies on a mounted heat sink blower that is fed from a dedicated 115 V/50–60 Hz AC tap, and this airflow path evacuates losses produced at full current. The internal logic and power components remain within operating limits as long as ambient air stays in the range of 5 to 45 °C. Because the cooling circuitry uses forced cooling, cabinet temperature rise is minimized and mounting options remain flexible. Generation code 3 identifies the control hardware revision and matches the unit with compatible supply and feedback modules in the same release.

Installation altitude can reach 1000 m above sea level before derating becomes necessary, supporting most factory floor elevations. Parameterization and diagnostics are handled through the built-in Serial interface (RS-232-C), so setup software can adjust loop gains or read fault memory without opening the enclosure. For synchronized motion, the controller provides a second encoder input, permitting spindle feedback or auxiliary motor feedback to be wired directly to the drive. Speed commands arrive as an analog speed command voltage, enabling the CNC to deliver high-resolution velocity references without a fieldbus layer and keeping response times consistent with legacy machine architectures.