Over voltage i.e. transient over-voltage, protecting device e.g. varistor lightening arrester, for electrical equipment or installation, has heat-sensitive units causing mechanical unit displacement to activate trigger system

摘要

The device has a mechanical unit constituted of a triggering bar (15) and a mast (21) cooperated with a set of heat-sensitive units e.g. bi-metal switch (19), and a trigger device of an electrical disconnecting apparatus e.g. magnetic switch. The heat-sensitive units and the mechanical unit are arranged so that the heat-sensitive units cause displacement of the mechanical unit from the deformation of the heat-sensitive units to activate the trigger system when the heat-sensitive units exceed a given temperature threshold.