PURPOSE: To execute a measurement safely, by inserting a high voltage insulated wire to a cover and case molding with plastic, and evacuating the case through a through-hole part provided on the cover, and after that, inject-molding hardening resin, in a secondary side electric circuit of a high voltage switch gear.
CONSTITUTION: A cover 1 and a case 2 molded with plastic are fixed by screws 4a, 4b by placing rubber packing 3 between them. One end 5a of a core wire of a high voltage insulated wire is soldered or brazed to L type fixed metallic fittings 6. A resistor 7 for suppressing a leakage current is soldered between the metallic fittings 6 and metallic fittings 8 of a channel shape, and is electrically connected. The metallic fittings 6, 8 are fixed to the case 2 with screws 9a, 9b, and an insulation resistance terminal 10 constituted of a metallic steel bar is fixed to the metallic fittings 8 with a screw 11. The cover 1 and the inside of the case 2 are evacuated from a round hole 1a of the cover 1, and thermosetting resin 12 is inject-molded. In this way, insulation resistance can be measured safely by connecting the wire 5 to a secondary side terminal of a high voltage switchgear, and by a round hole 10a provided by sinking from the cover 1.
NISHISAKO SHIZUTAKA
ITOU NAOKI
MITSUBISHI ELECTRIC CORP
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