Abstract: A disconnect switch for use in a metal-encapsulated high-voltage switching installation, wherein the switch includes a movable switching pin, a mating contact axially associated therewith, and a cylindrical member arranged in surrounding spaced relationship to the mating contact. The cylindrical member is further formed so as to extend beyond that end face of the mating contact which is in facing relationship with the switching pin, whereby the member projects into the gap between the switching pin and the mating contact when the disconnect switch is in the "off" position and surrounds the switching pin when the switch is in the "on" position.

Abstract: A surge voltage arrester contains a series circuit arrangement of spark gaps and voltage-dependent resistors. The voltage-dependent resistors include a semi-conductive material having an exponent .alpha. of voltage dependence which is at least 10. The surge voltage arrester makes it possible to manufacture high-capacity surge voltage arresters with spark gaps exhibiting a very simple construction. This effect is based on the fact that the voltage-dependent resistors assume the actual arrester function and the spark gap, therefore, are essentially only used for switching the arrester on and off. The arrester is particularly suitable for application in networks for electrical power distribution.

Abstract: The invention is directed to a laminar insulating material for electrical apparatus insulated by a fluid such as an insulating gas or an insulating liquid. The laminar insulating material includes two cover layers which are made of a material of relatively high density and an insulating material of relatively low density which is permeable for the fluid and fills the space between the cover layers.The invention is particularly well suited for the manufacture of the housings of overvoltage arresters which are arranged in the metal encapsulation of a gas-insulated, high-voltage installation. The laminar insulating material accomplishes here a faultless separation between the insulating gas in the metal encapsulation and that in the overvoltage arrester. Gases which penetrate the cover layers can be led off to the outside from the gas-permeable insulating material.