Siemens 3KM8221-3UA20 Electromechanical Switch

Siemens 3KM8221-3UA20 is a DIN-mounted electromechanical switch disconnector with fuse from Siemens’ 3KM family, designed to provide isolation and protection in industrial control panels. It is rated for 125 A, combining a robust disconnection mechanism with a fuse element to allow safe circuit interruption and overcurrent protection in low-voltage distribution applications. The device is intended for use in motor control centers and switchgear assemblies where reliable isolation of feeders or branch circuits is required within control panels and industrial equipment. As part of the 3KM line, this model supports integration within standard Siemens switchgear configurations and is used to consolidate switching and protection functions in compact asembly footprints.