Product Description:

The KDA 3.2-050-3-L0D-U1 is manufactured by Bosch Rexroth Indramat and belongs to the KDA Spindle Drives series. It is Series 3, Version 2. The unit is used in CNC machines and machining centers to regulate spindle speed and torque through closed-loop control of a main motor. By using a heat sink blower with internal power electronics, the drive converts a fixed DC bus into a controlled three-phase output and maintains stable temperature conditions inside the cabinet. This arrangement helps the spindle respond consistently during acceleration, steady cutting, and deceleration.

The power section is energized from a bus of 300 VDC, and the inverter can deliver up to 50 A of continuous output current to the spindle motor. Cooling is supported by a blower supplied with 115 V AC, 50–60 Hz, and this auxiliary circuit operates when the heat sink temperature rises above its setpoint. Airflow across the fins is increased by forced cooling, allowing the drive to maintain its current rating within an ambient range of 5 to 45 °C. Operation is permitted at elevations up to 1000 m above sea level, where the blower can still provide the airflow needed for heat removal.

Velocity reference data reach the power stage over a SERCOS interface, while separate motion controllers can also transmit a digital position command value when tighter synchronization is required. Heat removal is handled by a mounted heat sink blower fixed to the rear panel, so no external ducting is needed. The control board does not include a second encoder input, so all motor feedback must pass through the primary channel from the spindle motor encoder. This layout keeps the feedback path simple and supports coordinated spindle operation when the machine requires closely timed motion.