Product Description:

The KDA 3.2-100-3-LQD-U1 spindle drive is produced by Bosch Rexroth Indramat as part of the KDA Spindle Drives series, generation 3, version 2. Deployed between the machine control and a high-speed spindle motor, the unit converts DC bus energy into regulated three-phase output while exchanging setpoints and feedback with the motion controller. By doing so, it provides precise rotational velocity and torque regulation required for milling, drilling, and grinding centers that rely on tight spindle speed tolerances during machining cycles.

Its power section is sized for a continuous phase current of 100 A, allowing the connected motor to handle high cutting loads without entering current limit. The internal DC link is supplied by a common supply module at 300 VDC; this mid-level voltage balances response time with insulation demands on the stator windings. Thermal management is handled by a mounted heatsink blower that removes heat directly from the power semiconductors, and airflow is increased through forced cooling to keep junction temperatures stable during long duty cycles. The blower itself draws auxiliary power from a single-phase source rated at 115 V/50–60 Hz, simplifying cabinet wiring because no separate transformer is needed. Dynamic speed references are transmitted over the SERCOS interface, so the drive can be integrated into multi-axis networks that require deterministic communication and sub-millisecond update times. This communication path helps the spindle follow rapid command changes during acceleration, deceleration, and speed-holding intervals.

The drive operates properly only when the ambient air remains within 5 to 45 °C; outside this range, output derating or external conditioning is necessary. Installation altitude is limited to 1000 m above sea level because thinner air reduces cooling effectiveness and increases thermal stress on the blower. For orienting functions, a separate channel accepts a digital position command value, allowing the spindle to align its angular position during tool changes or orient cycles instead of relying only on speed control. This makes it suitable for machine sequences that require the spindle to stop at a repeatable angular location before the next operation begins.