Product Description:

The KDA 3.2-100-3-DQS-U1 spindle drive is built by Bosch Rexroth Indramat as part of the KDA Spindle Drives series. Designed for closed-loop control of high-speed machine-tool spindles, it receives logic and power commands from the parent CNC system. It modulates current to match dynamic load demands during cutting, drilling, or grinding operations. The drive is intended for spindle service where stable speed regulation is needed during rapid load changes and repeated machining cycles. That control behavior helps the spindle hold commanded speed as cutting forces rise and fall through different tool engagements and material conditions.

Its heat sink blower operates from an auxiliary supply of 115 V/50–60 Hz, so standard control power can run the fan. The power stage draws energy from a shared bus at 300 VDC, and the inverter can deliver a continuous spindle current of 100 A to handle aggressive acceleration profiles. Thermal limits are maintained when the surrounding air remains within 5 to 45 °C. Heat dissipation is aided by a mounted heat sink blower that pushes air across the fin stack instead of relying on passive convection, which helps the drive sustain full current in a compact enclosure. Current sensing is performed in each phase so the controller can react quickly to overload conditions and protect the spindle motor windings.

The cooling method is forced cooling, and it remains effective up to 1000 m above sea level where thinner air reduces cooling density. Command information arrives over a parallel control bus that uses a 16-bit digital parallel speed word, giving the control loop fine resolution across the spindle’s operating envelope. Parameter retrieval and service diagnostics can be performed through the integrated RS-232 C port, allowing direct laptop connection without additional adapters. This arrangement separates real-time control data from serial access tasks during setup and status review. The unit is in internal series 3 and version 2.