Abstract: A breaker circuit for disconnecting a surge arrestor is operable over a wide range of current values. A spring-tensioned conductor connects a first potential to a first terminal of the arrestor while a second terminal of the arrestor communicates with a second potential. The conductor is fuse-like and of predetermined current carrying capacity. The end of the conductor is connected to the first terminal by a solder bead of predetermined thermally-dependent strength. At low current values I.sup.2 R heating of the arrestor gradually weakens the solder bond to the first terminal, making it subject to disconnection by spring-induced tension force. At high current values, the conductor vaporizes to provide the rapid disconnect required to avoid explosion and/or fire.
Abstract: A breaker assembly for use in conjunction with a surge or lightning arrestor of the type that includes at least one varistor. The varistor circuit is enclosed within a substantially airtight housing that includes a hinged panel. A cantilevered arm is fixed to the hinged panel and includes, adjacent its free end, an aperture for interlocking a post. A conductive disk is fixed to the post and positioned vertically with respect to conductive arms to complete a circuit that includes the surge arrestor. The action of upper and lower springs, in conjunction with the post, serves to close or open such circuit. The position of the post is locked by the interaction of a notch therein with the cantilevered arm so that the opening and closing of the breaker switch is regulated by the attitude of the front panel of the housing that is, in turn, responsive to varistor-generated vapor pressure therein.