Product Description:

The spindle drive KDA 2.1-050-3-LQD-W1 belongs to the KDA Spindle Drives series produced by Bosch Rexroth Indramat. Within a CNC or machining center, this unit converts regulated DC bus energy into three-phase output that controls a high-speed motor, allowing precise spindle acceleration, deceleration, and torque regulation during cutting or drilling cycles. For motion commands, velocity setpoints arrive through the fiber-optic SERCOS interface, giving deterministic timing between the drive and the master controller. This control method helps the spindle respond quickly to changing load conditions during machining. That behavior is useful in cutting cycles where tool engagement changes rapidly and the drive must correct speed without hesitation.

The power electronics are rated for a continuous output of 50 A, so the connected spindle motor can draw that current without thermal derating. The inverter section is fed by a DC link voltage of 300 VDC, which supports the electrical speed range commanded by the drive. To keep the heat sink temperature stable, the unit carries an integral blower that operates from a dedicated 220 V/50–60 Hz single-phase source, isolating cooling power from the main DC bus. The fan is mounted directly on the aluminum heat sink in a mounted heat-sink blower arrangement. Airflow is provided by forced cooling, so the drive can sustain its current rating inside a sealed cabinet. Direct airflow over the heat sink helps remove losses from the power stage during long duty cycles, and the separate blower supply keeps cooling independent of the inverter output stage.

The permitted ambient range is 5 to 45 degrees Celsius, and operation outside this window may trigger thermal protection. Installation altitude is restricted to 1000 m above sea level, because thinner air reduces cooling effectiveness. A separate digital channel accepts a digital position command value, enabling the same hardware to execute contouring tasks where direct position words replace pure speed references. This allows the drive to support applications that require coordinated position control in addition to spindle speed control. When direct position words are used, the control can follow commanded paths without relying only on a speed reference.