Patent ID: 6968728

Claim:
A test tap adapter for use in providing electrical measurements in a transformer bushing and arranged for extracting samples of gases dissolved in insulating oil present in said transformer bushing so as to determine presence of said gases in said insulating oil, said test tap adapter including a tap connector, a tubular runway axially disposed in said tap connector and having a portion extending outside said tap connector, said portion constructed to penetrate into said transformer bushing and to soak in said insulating oil, an insulated conductor mounted in said tubular runway along entire length thereof and having a free length for connection to a conductor provided in said transformer bushing, means for connecting an end of said insulated conductor opposite said free length to an electrical measurement means, and means for anchoring said test tap adapter to said transformer bushing through an opening provided therein, with said outside portion of said tubular runway inside said transformer bushing in contact with said insulating oil, wherein said test tap adapter additionally comprises a gas diffusing member of nonconductive material mounted over said outside portion of said tubular runway, gas permeable but liquid impermeable means covering said gas diffusing member and arranged to allow permeation of gases that may be present in said insulating oil towards said gas diffusing member, a gas storage chamber linked to said tap connector, in operative contact with said gas diffusing member and means to allow passive diffusion of permeated gases present in said gas diffusing member towards said gas storage chamber for determining the presence of gases in said insulating oil.