Product Description:

The KDA 2.1-050-3-API-W1 belongs to the KDA Spindle Drives series manufactured by Bosch Rexroth Indramat. It is a spindle drive intended to regulate high-speed machine tool spindles and other rotation-critical axes in automated production lines. By converting a fixed DC link into controlled three-phase power, the unit supplies precise torque and velocity commands to an attached induction or synchronous spindle motor so that cutting, grinding, and drilling processes remain within programmed limits. This operating role makes it suitable for applications that require stable speed control, repeatable response, and coordinated spindle behavior during changing load conditions.

This model draws a continuous phase current of 50 A, allowing it to energize medium-frame spindle motors without saturation. The internal power electronics are fed from a stable link voltage of 300 VDC, which is generated elsewhere in the cabinet and routed directly to the drive bus bars. Thermal energy from the IGBTs is removed by forced cooling with a mounted heatsink blower. The blower operates from an auxiliary supply of 220 V/50–60 Hz, so the cooling circuit can remain active even when the main DC bus is discharged. This airflow across the heatsink helps keep semiconductor temperatures within the normal operating range during extended machining cycles.

Continuous operation is permitted at ambient temperatures from 5 to 45 °C. Installation is permitted up to 1000 m above sea level, where sufficient air density remains available for the cooling system to work as intended. Speed references are accepted through an analog voltage input, which allows direct connection to legacy CNC controllers that issue a ±10 V spindle command. For position-related coordination, the drive provides an incremental encoder output that replicates motor feedback for external control equipment. A second encoder input can also be wired for auxiliary feedback, such as a workpiece probe or a dual-motor arrangement.