Product Description:

The KDA 2.1-150-3-L0D-U1 is a regulated spindle drive built by Bosch Rexroth Indramat for the KDA Spindle Drives series. This unit mounts inside the drive cabinet of CNC machines and woodworking centers, where it converts intermediate-bus energy into controlled three-phase power for high-speed motor spindles. By linking to numerical controls, it supplies rapid torque changes and precise velocity regulation, supporting metal cutting, drilling, and grinding sequences in automated production lines. The regulated output helps the spindle follow commanded speed changes during acceleration, load variation, and orientation tasks.

For power integration, the drive connects to a DC bus rated at 300 VDC, which provides the operating voltage for the transistor bridge. The armature path can deliver up to 150 A of continuous current, enabling large-frame spindle motors to reach full load without derating during sustained machining. Thermal energy is removed by a mounted heat sink blower fixed to the backplate, and the fan motor draws from an auxiliary source of 115 V/50-60 Hz. This arrangement provides forced cooling, helping the drive maintain stable internal temperature during long roughing passes, repeated starts, and frequent speed reversals.

Command data reach the unit through a SERCOS interface that transmits speed commands, while a separate channel accepts a digital position command value for orientation tasks such as tool-change alignment. There is no second encoder input, so spindle positioning feedback is expected from the primary motor sensor alone. The drive operates within an ambient range of 5 to 45 °C and can be installed at elevations up to 1000 m above sea level. These operating limits apply to properly ventilated cabinet installations where the blower can move air across the heat sink without obstruction.