Product Description:

The KDA 3.1-050-3-DYD-U1 is a spindle drive produced by Bosch Rexroth Indramat as part of the KDA Spindle Drives series. The unit converts a regulated DC bus into three-phase output for high-speed machine-tool spindles while monitoring current, temperature, and position feedback. Within an automation cell, it functions as the power and control interface between the motion controller and the motor, enabling closed-loop speed and torque regulation during cutting, drilling, or grinding operations.

The drive stage draws up to 50 A of continuous motor current, which limits compatible spindle motor sizes and affects conductor sizing inside the cabinet. Its intermediate circuit is held at 300 VDC, so the upstream rectifier or supply module must be sized for that bus voltage. The integral heat sink blower is powered from an auxiliary line of 115 V/50-60 Hz, using a separate low-power source to keep the control electronics isolated from the cooling fan. Thermal energy is removed through forced cooling, and the blower is fixed directly on the housing as a mounted heat sink blower, which helps prevent recirculation of cabinet air and stabilizes internal device temperature during high-speed machining cycles.

Installation rules specify an ambient range of 5 to 45 °C, and staying within this window helps preserve component life and keeps temperature sensors within calibration margins. Operation is approved up to 1000 m above sea level, because reduced air density above that altitude can reduce cooling performance. Command data enter through a parallel bus that carries a 16-bit parallel digital speed setpoint, allowing high-resolution velocity updates from the CNC. A separate line transports the digital position command value, and a second encoder input allows spindle angle feedback to be cross-checked for synchronous tapping or spindle-orientation tasks. These interfaces support close axis coordination in multi-channel machining centers.