Abstract: Disclosed is a gas insulated switch device comprising at least two hollow cylindrical containers each accommodating top end portions of a system of line cables, and a disconnector having contacts coupled to the line cables via detachable conductors, wherein electrical tests on the cables, etc. in a first container can be conducted from a test window formed in a side wall of an adjacent second container, by means of a test tank attached thereto. The side walls of the first and second containers comprise a pair of opposing windows that are coupled to each other, via an electrically insulating spacer; branch conductors, which are disposed within the first container and have inner end portions that can be selectively coupled to the line cables or the contacts of the disconnector within the first container, comprise outer end portions projecting into the second container through the electrically insulating spacer disposed between two windows coupled to each other.

Abstract: In one-and-a half system gas insulated switchgear, three circuit breakers (3, 4, 5) are parallelly aligned between a pair of main buses (1, 2) with a right angle thereto and connected in series with each other between the main buses.

Abstract: An improved gas-type circuit-interrupter is provided having a pair of separable contacts, which establish an arc upon separation within a confined casing having a nozzle structure. The arrangement is such that during the initial portion of the opening operation of the interrupter, the established arc generates gas pressure, due to the hot arc energy developed in the arc, and this high-pressure gas is then stored within an adjacently-provided gas-storage region. At a later point in time in the opening operation, when, preferably, the current flow through the interrupter approaches its low instantaneous-current value, the aforesaid accumulated gas pressure, contained within said gas-storage region, returns in a gas flow to the arc, and effects the extinction thereof during such low instantaneous values of arcing current.