Product Description:

The KDA 3.1-050-3-APD-U1 is manufactured by Bosch Rexroth Indramat and belongs to the KDA Spindle Drives series. It functions as a closed-loop spindle drive that converts the shared DC bus energy of a multi-axis system into precisely metered three-phase output for machine-tool spindles. By processing analog speed references from the CNC and returning real-time tachometer or encoder data, the device maintains the commanded spindle speed during cutting, drilling, or grinding operations.

This drive draws its internal power from a DC link rated at 300 VDC and can deliver up to 50 A of continuous armature current to the spindle motor. Thermal management is handled by a 115 V / 50-60 Hz blower that is integral to the rear heat sink, and the airflow path supports the unit’s forced cooling design. Because the blower is part of a mounted heat sink blower assembly, installation space behind the cabinet plate is minimized. Analog speed command values enter through a differential input that tolerates common industrial noise levels, and the internal current regulator adjusts the IGBT bridge to track those references with a short rise time.

The drive can operate between 5 to 45 °C without performance derating, provided cabinet air circulates freely and humidity remains non-condensing. Altitude capability extends to 1000 m, so the drive can be installed in most factory settings without compensating for reduced air density. For digital integration, a position command input allows absolute spindle positioning during tool-change cycles, while a second encoder input accepts either spindle feedback or an auxiliary motor encoder for synchronous machining. Supplementary to the analog speed channel, these interfaces give the Series 3 hardware the flexibility needed for modern multi-channel CNC controllers.