Protective spark gap

The protective spark gap is an accessory for protection against lightning surges and is used in particular to protect antenna masts. It is an element that connects the mast to the earth via a cable, but is insulating in its initial state. Antenna masts do not act as lightning conductors and should not be connected to the ground. However, the mast spark gap becomes conductive at the precise moment when lightning strikes, by fugitively short-circuiting through an internal arc. This allows the mast to be discharged of the faulty current received, and the spark gap then returns to the insulating state. This device therefore provides protection for the antenna by bringing it to equipotentiality at the moment of impact.