KDA 3.3-050-3-LYS-U1

The KDA 3.3-050-3-LYS-U1 is produced by Bosch Rexroth Indramat and assigned to the KDA Spindle Drives series. Version 3 hardware in this line is designed to regulate high-speed spindle motors in CNC machining centers and similar automation cells. It forms part of the drive chain by receiving a speed setpoint from the motion controller and supplying adjusted DC bus energy to the attached power modules.

Its internal power stage draws from a DC bus of 300 VDC, and the drive can deliver a continuous output of 50 A to the connected spindle motor. Thermal discharge is handled by a mounted heatsink blower; this fan is energized by an auxiliary supply of 115 V/50–60 Hz. Because the airflow is mechanically directed through the fin stack, the unit operates in a forced cooling mode that maintains semiconductor junction temperatures within safe limits during heavy duty cycles. Continuous thermal control allows the drive to sustain its output without derating within the operating envelope defined for the product.

In field installation, the permissible ambient range is 5 to 45 °C, and performance is guaranteed up to 1000 m elevation, allowing cabinet placement on typical shop floors without additional cooling hardware. The drive receives its speed command through a SERCOS Interface, enabling deterministic exchange with Indramat or third-party motion controllers. For legacy diagnostic tools, a serial interface (RS-232-C) is provided, and an auxiliary channel accepts a second encoder and synchronous input for high-precision spindle orientation. These communication resources, together with the version 3 electronics, give integrators flexible feedback and control paths while maintaining electrical isolation between signal and power circuits.