Product Description:

The KDA 3.1-100-3-D0I-U1 is produced by Bosch Rexroth Indramat and belongs to the KDA Spindle Drives series. It functions as a regulated power module that converts shared DC-bus energy in a CNC cabinet into three-phase output for machine-tool spindles. By linking directly to the numerical controller, the unit maintains commanded speed and applies protective limits that help protect the motor and attached tooling during machining cycles. This arrangement supports stable spindle control during drilling, milling, and similar machine-tool processes.

The power stage is supplied from a link voltage of 300 VDC. Under continuous operation, it can deliver a nominal output current of 100 A. Thermal management uses a mounted heatsink blower powered by a separate 115 V, 50/60 Hz AC supply, so airflow is available independently of the DC link. The blower supports forced cooling through the fin channels to control semiconductor temperature during repeated acceleration and deceleration. Velocity references are received through a 16-bit parallel digital interface, giving the controller fine command resolution for high-speed spindle operation. That arrangement also helps the drive respond consistently to rapid speed changes.

The permitted ambient temperature range is 5 to 45 °C, so the enclosure must keep intake air within that window for continuous duty. Installation is allowed up to 1000 m above sea level, and higher elevations require output derating because reduced air density lowers cooling effectiveness. For position synchronization, an auxiliary port provides incremental encoder output, allowing external monitoring equipment or a master axis to track spindle angle in real time. The unit does not include a second encoder input, which simplifies wiring when only one feedback channel is used. This layout keeps the feedback path straightforward for systems that do not require an additional encoder connection.