Product Description:

The KDA 2.1-150-3-L0I-U1 belongs to the KDA Spindle Drives series manufactured by Bosch Rexroth Indramat. It is a spindle drive module used to regulate high-speed, high-power motor spindles found in CNC machining centers and grinding equipment. By converting the fixed DC link of a shared supply unit into a precisely controlled three-phase output, the drive provides closed-loop speed and torque control for repeatable metal-cutting and forming processes. This arrangement helps the spindle respond accurately during acceleration, steady-state running, and changing load conditions.

The heatsink blower that removes switching and motor losses is powered from an auxiliary line at 115 V/50–60 Hz, so a separate DC fan supply is not required. Cooling air is forced directly through a mounted heatsink blower, and the drive uses forced cooling to keep semiconductor temperatures within safe limits during continuous duty. The power stage draws energy from a DC bus rated at 300 VDC, and it can deliver up to 150 A of output current to the spindle motor. This current capacity supports demanding spindle acceleration and sustained cutting loads. A secondary encoder socket is omitted on this model, so only the primary feedback channel is available for position confirmation.

Installation is allowed up to 1000 m above sea level without performance reduction, and an incremental encoder output is available for downstream control tasks such as droop compensation or handwheel display. The unit maintains full functionality in ambient temperatures of 5 to 45 °C, which matches typical shop-floor conditions. All velocity commands are transmitted digitally over the SERCOS interface, ensuring deterministic communication with the machine controller. This communication method supports stable coordination between the spindle drive and the rest of the motion system.