Product Description:

The KDA 2.1-150-3-LQ0-W1 spindle drive is produced by Bosch Rexroth Indramat for the KDA Spindle Drives series. As a spindle drive, it serves as the power stage between the CNC controller and high-speed induction or synchronous spindle motors, regulating torque and speed during cutting, grinding, and drilling cycles. In machine tools, it controls motor current so the spindle can follow programmed speed changes and maintain torque during load variations. The unit is version 2 and is intended for cabinet mounting in automated equipment where fast acceleration, steady speed holding, and repeatable machining performance are required.

Its internal DC link is supplied with 300 V DC, and the output stage can deliver a continuous line current of 150 A to the motor for rapid torque buildup under heavy loads. Thermal energy from the power semiconductors is removed by a mounted heat sink blower that operates from 220 V/50–60 Hz, so the fan supply remains separate from the main power section. Speed reference data are accepted through the SERCOS interface, which provides deterministic fiber-optic communication with the master control. That communication path supports coordinated motion with the CNC system while the power stage responds quickly to changing spindle demand.

The drive uses forced cooling, so installation must keep airflow across the cooling fins unobstructed. Reliable operation is permitted between 5 to 45 °C, and derating is required outside that range. Installation altitude is limited to 1000 m above sea level because thinner air reduces the blower’s cooling effectiveness. The unit has the lack of an additional interface option, so no extra expansion card is fitted and field wiring is limited to the standard power, cooling, and communication connections. Cabinet layouts should also prevent warm exhaust air from circulating back through the heat sink.