Product Description:

Bosch Rexroth Indramat manufactures the KDA 2.1-150-3-LQD-W1 within the KDA Spindle Drives series. This drive regulates torque and speed for machine-tool spindles by converting bus power into three-phase output and exchanging setpoints with higher-level CNC controllers through fiber-optic links, so spindle speed remains stable during cutting cycles and rapid changes in load. The design supports dynamic acceleration of high-inertia spindles, while the heat sink blower and internal diagnostics help maintain continuous operation inside electrical cabinets that contain other power electronics.

The power section is dimensioned for a continuous output of 150 A, so matching contactors, fuses, and busbars must be sized for that current. It operates from a shared DC link at 300 VDC, allowing several drives to be connected to one supply in shared-bus machine architectures to minimize transformer capacity. Thermal energy is removed by a mounted heat sink blower in a forced cooling arrangement that helps prevent derating during heavy-duty cycles. The blower motor itself uses a single-phase 220 V/50–60 Hz supply, so no separate low-voltage source is required. Speed commands are passed over the fiber-optic SERCOS interface, letting the spindle drive share synchronous bus timing with axis drives during coordinated interpolation and other synchronized machine functions.

The permissible ambient range of 5 to 45 °C sets cabinet climate requirements and helps keep semiconductor junction temperatures within design margins. For position loops that demand finer resolution than velocity control alone can offer, a separate channel accepts a digital position command value, allowing the drive to close position control at the device level when needed. Installation is restricted to sites no higher than 1000 m above sea level, because reduced air density above that altitude lowers cooling efficiency and can require additional derating or forced ventilation.