Product Description:

The KDA 3.1-150-3-DQI-U1 is a spindle drive manufactured by Bosch Rexroth Indramat and supplied within the KDA Spindle Drives series. As a regulated power stage for high-speed machining spindles, the unit converts the fixed DC link of a cabinet supply into controlled three-phase output and regulates motor speed through a digital interface. In automated machine tools, it delivers closed-loop torque and velocity control so cutting forces and surface finish remain consistent throughout each production cycle. That regulation helps the spindle respond smoothly during acceleration, constant-speed cutting, and orientation tasks in machine-tool applications.

The drive operates from a DC link of 300 VDC, and its power section can deliver a continuous output of 150 A. This current rating is the maximum continuous motor armature demand the controller can support without derating. A forced cooling path moves air across the heat-dissipating fins to keep semiconductor junction temperatures within safe limits. Reliable thermal behavior is maintained as long as ambient air stays between 5 to 45 °C. Full output is specified only up to 1000 m above sea level, because thinner air at higher elevations reduces convective heat transfer. The combination of current capacity and active airflow supports demanding spindle duty in enclosed machine cabinets.

An integral blower for the heat sink is supplied from an auxiliary source of 115 V at 50/60 Hz, eliminating the need for separate external fans. The drive uses a mounted heat sink blower, so enclosure layout simply requires an unobstructed airflow path. Position feedback can be shared with higher-level numerical controls through an incremental encoder output, enabling synchronized axes or spindle orientation functions. Speed reference data arrive on a parallel bus through a 16-bit parallel digital interface, allowing fine-resolution changes without analog drift. This arrangement supports precise speed trimming when the spindle must match programmed cutting conditions.