Abstract: At least one conductor is disposed in sealed vessel, which is filled with insulating gas, an hand hole is provided to a part of sealed vessel and is closed by a sealed cover, and optical fibers are disposed that form a closed loop surrounding conductor in sealed vessel. Optical fibers are hermetically led out of sealed vessel from sealed cover and are provided with at least a light source unit and an optical signal processor unit at the lead-out end. An airtight hollow tube disposed looping around leaving a predefined distance of separation is provided to conductor in sealed vessel, the end of tube is hermetically connected to sealed cover by sealing/bonding means, and optical fibers can be inserted in sealing/bonding means.

Abstract: Insulating spacer 1 has insulating molded member 3 molded as a single body with insulating material such as epoxy resin, in which at least one electric conductor 2, a grounding shield surrounding the electric conductor(s), and Optical fiber 14 of Faraday-effect element are embedded to form a build-in configuration. The grounding shield can be formed of cylindrical shielding member 15 made of metal wires, metal strips, or a cylindrical metallic member having a perforation of a plurality of small holes thereon. The aforementioned optical fiber 14, which is to be used as a component of an optical current transformer, is put in a certain place in cylindrical shielding member 15.

Abstract: At least one conductor is disposed in sealed vessel, which is filled with insulating gas, an hand hole is provided to a part of sealed vessel and is closed by a sealed cover, and optical fibers are disposed that form a closed loop surrounding conductor in sealed vessel. Optical fibers are hermetically led out of sealed vessel from sealed cover and are provided with at least a light source unit and an optical signal processor unit at the lead-out end. An airtight hollow tube disposed looping around leaving a predefined distance of separation is provided to conductor in sealed vessel, the end of tube is hermetically connected to sealed cover by sealing/bonding means, and optical fibers can be inserted in sealing/bonding means.

Abstract: Insulating spacer 1 has insulating molded member 3 molded as a single body with insulating material such as epoxy resin, in which at least one electric conductor 2, a grounding shield surrounding the electric conductor(s), and Optical fiber 14 of Faraday-effect element are embedded to form a build-in configuration. The grounding shield can be formed of cylindrical shielding member 15 made of metal wires, metal strips, or a cylindrical metallic member having a perforation of a plurality of small holes thereon. The aforementioned optical fiber 14, which is to be used as a component of an optical current transformer, is put in a certain place in cylindrical shielding member 15.