Hitachi, Ltd.

Haruji Nakano

Kazuaki Oishi

Satoshi Miwada

A compact-type gas-insulated switchgear apparatus is disclosed, in which movable contacts of a disconnector and a ground switch arranged in a cable head casing are adapted for switching operation in parallel to the axis of the cable head casing. A connecting conductor connecting stators of the disconnector and the ground switch is arranged in a position perpendicular to the axis of the cable head casing. A connecting opening is formed in the side wall of the cable head casing at a part thereof corresponding to the end of the connecting conductor. It is thus not necessary to increase the diameter of the cable head casing for the movable contacts of the disconnector and the ground switch performing substantially parallel operation, and other electrical equipment may be connected along the extention of the connecting conductor connecting the stators of the disconnector and the ground switch without modifying the cable head casing.

Compact-type gas-insulated switchgear apparatus

A ground test switch comprises a terminal plate electrically connected to a movable contact member but electrically insulated from a closed vessel enclosing a high-voltage conductor, a grounding conductor disconnectably electrically connecting the terminal plate to a member maintained at ground potential, and a locking device locking the movable contact member against movement when the grounding conductor is detached from the connecting position. The operator may forget to mount the grounding conductor in the switch again after a ground test. Such a trouble can be readily detected because the movable contact member is locked against movement.

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Hitachiota, Japan

Haruji Nakano