Product Description:

The Bosch Rexroth Indramat KDA 3.1-050-3-A00-U1 belongs to the KDA Spindle Drives series. As a spindle drive, it supplies controlled three-phase power to high-speed machining spindles and allows a CNC controller to command rotational speed with feedback. Within an automation cell, the unit bridges the DC power supply and the motor, regulating current to match changing cutting load and protecting the machine tool from overcurrent and thermal drift. That control behavior helps the spindle maintain steady speed as tool engagement changes during drilling, milling, and other variable-load processes.

The version 3 drive draws its intermediate circuit from a 300 VDC supply, which stabilizes inverter operation and limits line-side harmonics. Under continuous load, the power section can deliver 50 A, giving the spindle enough current for rapid acceleration and sustained cutting duty. Thermal energy is removed by a heat sink-mounted blower, and airflow is enhanced through forced cooling to help prevent semiconductor derating during long machining cycles. The blower is powered by an auxiliary 115 V/50–60 Hz source, so the cooling system can be wired separately from the main DC link.

The control section interprets the speed reference as analog, allowing conventional ±10 V commands from a motion controller instead of digital fieldbus traffic. Reliable operation is specified between 5 to 45 °C, and installation is permitted up to 1000 m above sea level before additional derating is required. Communication hardware is kept simple because the model has no additional interface option and does not include a second encoder input. This arrangement suits legacy machining centers that use straightforward analog control and compact wiring, and it reduces the number of external connections needed in the control cabinet.