LIGHTNING ARRESTERS
Dorvial Michel, a scientist at Compagnie Industrielle de Tubes et Lamps Electriques Citel, a French company, has devised a lightning arrester. The device has an external metal casing containing a neutral gas (that does not react easily), a metal electrode and a fuse. Under normal conditions, the electrode is electrically insulated from the outer casing by an insulating layer having few holes. During a lightening, when the electrical energy exceeds the threshold value, the fuse element gets heated beyond its melting point. As the melt flows through the holes in the insulating layer, an electrical short circuit occurs, resulting in discharging the current.