To provide an electric equipment where the pressure-sealed tank of an incombustible electric apparatus provided with incombustible liquid as insulating medium can be lessened in size, it is easily detected when its pressure gas partitioned chamber has an accident, and a failure position can be easily judged.

An electric equipment body 4 is housed in a hermetically sealed case 1, the sealed case 1 is charged with incombustible liquid 5, and when the incombustible liquid 5 is compressed with inert insulating gas 10, the required volume of inert insulating gas 10 is composed of cases such as an on-load tap changer housing case 6, a high-voltage cable case 8 and others, these cases are linked together with a connecting piping 15, and throttle valves 16 are provided in the connecting piping 15 at prescribed positions, whereby it is easily detected when a trouble occurs at these partitioned sections.