Product Description:

The KDA 2.1-100-3-A00-U1-115 is a spindle drive module produced by Bosch Rexroth Indramat as part of the KDA Spindle Drives series. Designed for axis packages that require closed-loop speed control of high-speed machine tool spindles, the unit converts a fixed DC link into a three-phase output while handling thermal management through an integrated blower. Within automated machining centers, the drive links the motion controller with the motor, enabling accurate torque regulation during drilling, milling, or grinding operations. It is intended for spindle systems that need steady speed regulation during changing cutting loads. The module is suited to machine tool applications where spindle speed must respond quickly to control commands.

In operation, the drive draws its intermediate circuit energy from a 300 VDC supply that is common to the drive rack. Under continuous load, it is rated for a maximum phase current of 100 A, allowing direct connection to large-frame spindle motors without an external step-up gear. Thermal energy is removed by a heat sink fan powered from a dedicated 115 V/50-60 Hz auxiliary line, and airflow across the fins is maintained by forced cooling to keep semiconductor junctions within their intended operating range. The velocity reference enters the controller as an analog command, enabling proportional speed control from legacy CNC outputs. This arrangement supports stable spindle operation during long machining cycles and repeated load changes.

The drive can operate continuously between 5 to 45 °C, and installation is approved up to 1000 m above sea level without current derating. Because the cooling assembly is a mounted heat sink blower, separate ducting is not required when unrestricted air access is available. Open airflow around the module remains important so the blower can move heat away from the power section effectively. The model ships with no additional interface option, and its X7 socket omits a second encoder path, so wiring is limited to the primary tachometer feedback and analog reference. This layout keeps the signal path focused on the standard control connections used by typical spindle installations.