| 摘要 |
<p>PROBLEM TO BE SOLVED: To form a gas-insulated switch gear which may be used while the helium gas is left for leakage inspection thereof using the insulation gas, as the insulation medium, in the mixing ratio of dry air or nitrogen and oxygen of almost 8:2 which is equal to that of the dry air. SOLUTION: In the gas-insulated switch gear, the helium gas is filled for leakage inspection of a vessel accommodating a switching device thereof. The helium gas for inspection is left thereon, and the insulation gas is filled in the pressure higher than the atmospheric pressure in the mixing ratio of the dry air or nitrogen and oxygen almost as 8:2 which is equal to that of dry air.</p> |
