Product Description:

The KDA 2.1-100-3-APD-U1 is a spindle drive from Bosch Rexroth Indramat's KDA Spindle Drives series. In a machining center or grinding line, it converts the fixed DC link of a cabinet into the regulated three-phase output required to accelerate and decelerate a motorized spindle with precision. By combining high current capability with several command interfaces, the unit forms the link between a CNC controller and the mechanical spindle, managing torque, velocity, and position during metal-cutting and similar industrial tasks.

The drive draws its intermediate power from a DC bus rated at 300 VDC, and it can deliver up to 100 A of continuous output to the spindle windings, allowing rapid speed changes under heavy cutting loads. A dedicated heat sink blower runs from an auxiliary supply of 115 V/50-60 Hz, which keeps semiconductor temperatures within limits when the cabinet fan alone is insufficient. The blower is attached directly to the heat sink in a configuration described as a heat sink-mounted blower. The unit uses forced cooling, so thermal performance does not depend on natural convection or cabinet orientation, which is important in densely packed multi-axis systems.

The unit maintains full ratings in ambient conditions from 5 to 45 °C and at installation heights up to 1000 m above sea level. Control electronics accept a digital position command value for precise spindle orientation, while velocity is modified through an independent analog speed command value, letting a CNC program select either mode without rewiring. A secondary encoder socket is present for spindle or auxiliary motor feedback, and additional logic terminals transmit drive status to the higher-level controller so that thermal limits, current utilization, and motion commands remain synchronized with real-time machining requirements.