Product Description:

The KDA 2.1-050-3-DYI-U1 is a spindle drive manufactured by Bosch Rexroth Indramat and supplied in the KDA Spindle Drives series. Designed for machine-tool and automation duties, the unit converts a constant DC bus into variable three-phase power so that a mechanical spindle can accelerate, brake, and maintain speed with digital precision. By integrating position feedback channels and an onboard heat sink blower, the drive provides closed-loop torque control for high-speed cutting and drilling assemblies. It is suited for spindle applications that require responsive acceleration and stable speed regulation during changing load conditions.

The drive operates from a DC link of 300 VDC, which is supplied by a rectifier section that feeds the inverter stage. A continuous output of 50 A lets the controller energize medium-frame spindle motors under typical machining loads without thermal derating in normal operating conditions. Thermal rise is removed through a mounted heat sink blower, and forced cooling moves ambient air directly across the power modules. The blower is powered from an auxiliary line rated at 115 V/50-60 Hz, keeping ventilation active while the main DC bus discharges. Revision 2 also includes a second encoder input and a synchronous input for expanded feedback schemes.

The drive can operate in ambient temperatures from 5 to 45 °C, and installation is permissible up to 1000 m elevation before additional derating is required. Speed references are accepted as a digital 16-bit parallel value, allowing fine command resolution from CNC controllers and other compatible control hardware. Real-time motor motion can be forwarded to external diagnostics through an incremental encoder output, and that signal complements the second encoder channel accepted by the unit. This interface arrangement supports closed-loop spindle control while also providing motion data to connected monitoring devices.