Product Description:

The KDA 3.2-050-3-LPS-U1 belongs to the KDA Spindle Drives series manufactured by Bosch Rexroth Indramat. As a spindle drive, it supplies regulated three-phase power to high-speed machining or grinding spindles, allowing coordinated speed control through digital motion controllers. The unit interfaces with the drive system, converts the common DC bus into a variable output for the motor, and supports feedback from a secondary encoder so that the CNC or PLC can maintain precise spindle positioning during tool changes and threading cycles. This arrangement supports stable spindle behavior during speed changes, orientation tasks, and other motion sequences that depend on accurate control.

This model delivers a continuous output of 50 A while operating from a DC bus of 300 VDC, giving it the current capacity required for rapid acceleration and deceleration of large-inertia spindles. Speed commands enter the control loop over the SERCOS interface, which transmits setpoints and status data in a fiber-optic ring to reduce electromagnetic interference. A secondary serial RS-232C interface is available for local access to parameters and diagnostic data without interrupting the main communication path. The heat sink blower that removes switching-loss heat is powered by an auxiliary supply of 115 V/50–60 Hz. Using a separate single-phase line keeps the cooling circuit independent of drive output and helps maintain steady thermal management during spindle operation.

A mounted heat sink blower combined with forced cooling helps keep semiconductor temperatures within acceptable operating limits during prolonged high-speed use. The drive can be installed in production areas where the ambient temperature remains between 5 to 45 °C, and it can operate at elevations up to 1000 m above sea level without derating. These operating limits suit machine tools and similar equipment that run for long periods under changing spindle loads. The cooling method also supports enclosed cabinet layouts where heat must be removed consistently to protect power components and maintain stable drive response.