Product Description:

Bosch Rexroth Indramat built the KDA 3.1-100-3-D0S-W1 spindle drive for the KDA Spindle Drives series. The unit converts a fixed DC bus into variable voltage and frequency outputs that regulate high-speed machining spindles in CNC systems. The control stage adjusts output voltage and frequency together so the spindle can follow programmed speed changes smoothly during cutting operations. By integrating current control, speed-loop processing, and heat sink ventilation hardware, the product maintains constant spindle torque across a wide speed band, making it suitable for milling, drilling, and grinding heads that require stable acceleration profiles.

The drive operates from a DC bus of 300 VDC and can deliver a continuous phase current of 100 A to the connected spindle motor. Thermal energy is removed through forced cooling, which uses an internal fan-speed controller and an externally mounted heat sink to stabilize component temperatures under full load. Commanded speed is accepted as a digital 16-bit parallel word, giving the motion controller fine resolution when synchronizing tool paths. For setup and diagnostic tasks, the front panel includes an RS-232-C serial interface that allows parameter downloads and status queries from a host computer. A second encoder input is not provided, which simplifies cabling when only a primary feedback channel is required.

The heat sink blower is supplied from an auxiliary line of 220 V at 50/60 Hz, and the assembly itself is a mounted heat sink blower secured to the unit's rear panel to keep the airflow path short. Installation is permitted at ambient temperatures from 5 to 45 °C, and site elevation should not exceed 1000 m above sea level. Within that temperature range, the electronic components remain inside their thermal derating limits during continuous operation. Above that altitude, lower air density can reduce the effectiveness of the forced-air cooling path.