Product Description:

The KDA 2.1-150-3-A00-W1 is manufactured by Bosch Rexroth Indramat within the KDA Spindle Drives series. As a closed-loop drive, it converts direct-current bus power into variable three-phase output so a machine-tool spindle can accelerate, decelerate, and hold programmed surface speeds during cutting or grinding operations. An internal control channel receives an analog speed reference from the CNC and modulates output voltage and frequency accordingly, allowing the unit to fit into multi-axis automation where synchronized spindle motion is required. This arrangement supports stable spindle speed during machining cycles that involve changing load conditions. It is intended for spindle service in machine tools that require repeatable speed regulation across different process steps.

The power section is supplied from a common bus at 300 VDC, and its output stage is rated for a continuous motor current of 150 A. These ratings indicate the continuous electrical load the drive can supply under steady spindle operation. Thermal energy produced by the switching devices is removed by a mounted heat sink blower that operates on an auxiliary line of 220 V/50-60 Hz. Because airflow moves across external fins rather than relying on convection, the design uses forced cooling to keep semiconductor temperatures within range in densely populated cabinets. Speed demand reaches the regulator as an analog voltage, simplifying integration with legacy CNC controllers that still issue ±10 V references. There are no expansion slots for additional communication, and the hardware lacks a second-encoder socket, so feedback is limited to the primary resolver or encoder channel provided by the spindle motor.

The drive can operate continuously at ambient temperatures from 5 to 45 °C and at elevations up to 1000 m above sea level without derating, making it suitable for standard production floors rather than refrigeration areas or high-altitude sites. The unit is in Series 2. The absence of extra option cards reduces cabinet wiring, and the forced-air path must remain clear so cooling air can move freely through the heat sink. This layout keeps the base configuration focused on spindle control rather than optional interface expansion.