Product Description:

The KDA 1.1-150-300-W1-115 is a transistorized spindle drive module produced by Bosch Rexroth Indramat and assigned to the KDA Spindle Drives series. Intended for machine-tool spindles, the module forms the bridge between the common DC bus and the three-phase motor windings, allowing closed-loop speed and torque control during turning, milling, and grinding operations. It returns tachometer and temperature data to the CNC, which helps maintain dimensional accuracy and reduce thermal drift during repeated machining cycles. Its housing is arranged for cabinet mounting, where it can share a DC link with additional axis drives.

It draws energy from a 300 VDC intermediate circuit and can deliver a continuous phase current of 150 A, making it suitable for high-power spindles that require fast acceleration. Thermal management is handled by a mounted heat sink blower, and the integral fan pushes air across the external fins so the internal semiconductor junctions remain within their allowable temperature range. This arrangement uses forced cooling, which removes heat efficiently and supports sustained peak torque when the required airflow clearance is available. The cooling method also helps the unit operate reliably in standard industrial cabinets without the need for more complex external cooling equipment.

The drive is intended for ambient temperatures of 5 to 45 °C and for operation at elevations up to 1000 m above sea level. Operation above that altitude reduces cooling effectiveness because thinner air lowers fan mass flow and convective capacity. The unit must be installed in a vertical mounting position so warm air can exit upward and airflow across the heat sink is not restricted. This operating range fits factory areas that are not refrigerated and are not exposed to excessive process heat.