Product Description:

The KDA 2.1-050-3-LQI-U1 spindle drive is produced by Bosch Rexroth Indramat as part of the KDA Spindle Drives series. Designed to regulate high-speed machine-tool spindles, the unit converts regulated DC bus energy into three-phase output while supervising motor behavior through digital control and feedback channels. In automated machining centers, it provides steady torque, rapid acceleration, and coordinated deceleration so the spindle can follow programmed profiles without disrupting adjacent axes. Because the model is coordinated through digital command values, it fits modular drive cabinets that rely on centralized power supplies.

This KDA variant draws its bus power from a nominal 300 VDC supply. Under continuous loading, it can deliver a rated output of 50 A, allowing it to drive medium-frame induction or synchronous spindles without current derating. Thermal management is handled by the drive itself. A blower moves air across the external heat sink, and the airflow is maintained by an auxiliary line rated at 115 V/50-60 Hz. The heat sink circuit uses forced cooling, so cabinet temperature has less influence on transistor junctions during prolonged roughing cycles. Velocity and torque references are transmitted digitally, and the speed command channel uses the SERCOS interface, enabling deterministic updates and straightforward parameter access from the master controller.

The drive’s permissible ambient range spans 5 to 45 °C, aligning with typical shop-floor conditions. Installation is supported up to 1000 m above sea level; within this altitude, the blower maintains adequate air density for the cooling channel. For feedback distribution, the unit provides an incremental encoder output, giving other controller channels a direct tachometer signal without extra converters. The power stage uses a mounted heatsink blower, so rear-panel clearance is needed when arranging multiple KDA modules side by side.