Product Description:

The KDA 3.1-150-3-AYI-U1 is a spindle drive developed by Bosch Rexroth Indramat for the KDA Spindle Drives series. It converts a regulated DC link into three-phase power for high-speed machining spindles and reports actual speed to the CNC controller. Integrated blower cooling, encoder interfaces, and an analog speed command allow closed-loop operation on lathes, milling centers, and grinding machines. Because it regulates spindle power directly, the drive is suitable for machines that need quick speed changes between machining steps.

The power section operates from a DC link of 300 VDC and can deliver a continuous output of 150 A to the motor windings, allowing large spindle frames to accelerate without derating. The heatsink blower is supplied from an auxiliary line at 115 V/50–60 Hz, so the cooling fan can be powered from common control power. Thermal energy is removed by a mounted heatsink blower that uses forced cooling, which helps keep semiconductor temperatures under control during prolonged high-current duty. Speed is commanded through an analog reference voltage, allowing simple velocity control in legacy NC systems while supporting closed-loop supervision. The continuous current capability supports steady torque production during long cutting cycles and other sustained spindle loads.

The environmental envelope spans 5 to 45 °C ambient air and installations up to 1000 m above sea level, so the drive can be mounted in typical shop-floor conditions. For feedback and synchronization, the front panel provides an incremental encoder output for downstream devices and a second encoder input and synchronous input for comparing position sources or coordinating multiple axes. These interfaces support speed matching and synchronized motion where the control system needs both spindle feedback and an external reference. That combination is useful in applications that use a master axis, external encoder, or synchronized tapping function. The layout also helps integrate the drive into machines that use separate measurement channels for monitoring and motion coordination.