Abstract: A power connector for providing overload protection for an electrical operating station connected to a power mains, composed of at least one overvoltage arrester of a first type which is capable of quenching the power mains surge current and at least one overvoltage arrester of a second type connected in series with said arrester of the first type, with the insulation of one overvoltage arrester, in its unfired state, meeting the requirements of a basic insulation or of the supplementary insulation for a protective insulation, and both arresters being constructed for dissipating the pulses generated by a direct stroke of lightning or nuclear electromagnetic pulses without adversely affecting the protection afforded thereby.

Abstract: In an arrester for limiting overvoltages in a low voltage power system and for coupling conductors which are normally resistively separated from one another for lightning protection, which arrester includes at least two electrodes spaced apart to define at least one spark gap forming an arc discharge region, and an insulating member holding the electrodes in spaced-apart relation, there is provided a chamber adjacent the arc discharge region and having a chamber wall of an insulating material which emits a quenching gas under the effect of heat and which is provided with at least one outlet aperture through which the gases emitted under the effect of the heat generated during arc discharge can escape.

Abstract: In an overvoltage arrester composed of two electrodes spaced apart to define a gas spark gap presenting an arc discharge region, and a spacer member of insulating material interposed between the electrodes and forming with the electrodes the walls of a chamber communicating with the arc discharge region, elements are disposed in the chamber to establish therein a labyrinth gas flow path between the arc discharge region and the spacer member.