Product Description:

Bosch Rexroth Indramat manufactures the KDA 2.1-050-3-DYD-U1 as part of the KDA Spindle Drives series. This unit is a spindle drive module that interfaces with digital CNC systems to control induction or synchronous spindle motors used in milling centers, turning machines, and automated assembly cells. By converting a regulated DC bus into variable three-phase output, the drive provides speed-accurate, torque-stable rotation for consistent surface finish and tool life in industrial automation. It is suited for machine tools that require repeatable spindle response during cutting, drilling, tapping, or indexing moves.

Latching onto a shared DC link, the drive operates from a bus of 300 VDC, drawing and returning energy as the spindle accelerates or decelerates. Under continuous duty, it can deliver 50 A of output current, which sets the thermal and conductor sizing for the installation. Heat generated by the power transistors is removed by a mounted heat sink blower, and the air path is intensified by forced cooling so internal temperatures remain within the allowable range over ambient temperatures of 5 to 45 °C. Within this ambient range, the drive can maintain stable current control and repeatable spindle behavior during long production runs.

The blower receives its power from a dedicated 115 V 50–60 Hz branch, allowing the fan circuit to be protected separately from the main power section. Installation is permitted up to 1000 m above sea level without derating. For motion coordination, the drive processes a digital 16-bit parallel speed command and a discrete position command value channel, and it also provides a second encoder input and a synchronous input for master-follower spindle arrangements or high-resolution feedback redundancy. This arrangement supports coordinated spindle behavior when the machine must synchronize rotation with feed motion or another axis. These data paths support accurate speed and phase alignment with the CNC control cycle.