Abstract: A fuse system protects an electric fence box from lightning strikes that hit a fence connected to the electric fence box via the fuse system. The fuse system includes at least one fuse connecting an output terminal of the electric fence box to the electric fence and an optional second fuse connecting a ground terminal of the electric fence box to earth ground. Each fuse includes a filament at least 12 inches long inside a non-conductive tube (e.g., Mylar). A first lead connects a first end of the filament to the output terminal of the electric fence box, and a second lead connects a second end of the filament to the electric fence.

Abstract: A high voltage circuit interrupter, having telescopic tubular insulating and conducting casings, contains an expulsion end sealing construction which hermetically seals and controls the expulsion rate of the interrupter. The expulsion end includes a sleeve, a thin, rupturable diaphragm affixed against the sleeve by cyanoacrylate cement, and an end cap. Epoxy cement is applied into the cap so that the space between the diaphragm and the end cap are filled forming a sealant layer therebetween. A main ferrule secures the strain element, and an auxiliary ferrule secures both the main ferrule and the end cap onto the end of the tubular insulating casing.

Abstract: A fuse cartridge for example of the cylindrical type comprising an insulating cylindrical body ending in two conducting end pieces and a fuse element connected electrically to the end pieces, further comprising two pistons housed in the body which are movable in translation in opposite directions to each other and collect the gases released by the electric arc at the time of its appearance, so that the pressure of the gases exerts on each piston a force which causes it to move towards a position in which the arc is totally sheared.

Abstract: An improved switch in which a contact is moved away from a stationary contact by ignition of a power cartridge. The ignited power cartridge pressurizes a chamber defined by the stationary contact and an insulative trailer mounted to the movable contact to open the switch. The movable contact and its trailer move conformally through a bore of an insulative liner. The trailer and liner are made of ultra high molecular weight polyethylene which is abrasion-resistant and has high surface lubricity--thereby ensuring free movement of the movable contact and the liner--and which is non-brittle--thereby ensuring that forces applied to the trailer by the power cartridge do not shatter it. An inflexible disc of Lexan or Nylon may reside at the interface of the movable contact and the trailer to obviate extrusion of the trailer about the contact due to the forces applied to the trailer.

Abstract: An electrical furnace heater construction having electrical heaters carried by a frame and having a current fused drawer-like lead unit movably carried by the frame and having leads for directly and electrically interconnecting to terminals of the heaters when the unit is in one position relative to the frame, the frame having terminals for electrically interconnecting the leads of the unit to power source leads so that the power source leads will be directly and electrically interconnected to the terminals of the heaters by the unit. A temperature responsive power device is carried by the frame and is responsive to the output temperature effect of the electrical heaters, the temperature responsive power device being operatively associated with the unit to move the unit out of the one position thereof to disconnect the leads thereof from the terminals of the heater when the temperature responsive device senses a certain adverse output temperature effect of said electrical heaters.