Abstract: A gas sample separated from transformer oil is circulated through an NDIR gas sensor system which obtains an acetylene concentration by calculating a detected acetylene concentration obtained by an absorption biased (“AB”) NDIR acetylene gas sensor, calculating a detected carbon dioxide concentration obtained by an AB NDIR carbon dioxide gas sensor, calculating a detected water vapor concentration obtained by an AB NDIR water vapor NDIR gas sensor and then determining the acetylene concentration from the detected acetylene concentration through use of the detected carbon dioxide and water vapor concentrations to compensate for their interference.

Abstract: A gas sample separated from transformer oil is circulated through an NDIR gas sensor system which obtains an acetylene concentration by calculating a detected acetylene concentration obtained by an absorption biased (“AB”) NDIR acetylene gas sensor, calculating a detected carbon dioxide concentration obtained by an AB NDIR carbon dioxide gas sensor, calculating a detected water vapor concentration obtained by an AB NDIR water vapor NDIR gas sensor and then determining the acetylene concentration from the detected acetylene concentration through use of the detected carbon dioxide and water vapor concentrations to compensate for their interference.

Abstract: An oil gas separation membrane combines a gas permeable yet oil and temperature resistant bulk polymer membrane such as poly(tetrafluoroethylene) and poly(tetrafluoroethylene-co-hexafluoropropylene); a porous metal support such as sintered metal frit disk made with stainless steel, bronze or nickel; and an highly gas permeable adhesive that bonds firmly the bulk polymer membrane and the metal frit surface together. The adhesive is either a homogenous polymer that has desirable gas permeability, or a coalescent porous polymer particulates network. A gas sensor employing the oil gas separation membrane for detecting and monitoring fault gases of oil filled electrical equipment requires no mechanical wearing or moving part such as pump and valve and the gas sensor is operated normally under various temperature and pressure conditions.

Abstract: A multi-gas sensor device for the detection of dissolved hydrocarbon gases in oil-filled electrical equipment. The device comprising a semiconductor substrate, one or more catalytic metal gate-electrodes deposited on the surface of the semiconductor substrate operable for sensing various gases, and an ohmic contact deposited on the surface of the semiconductor substrate. The semiconductor substrate comprises one of GaN, SiC, AlN, InN, AlGaN, InGaN and AlInGaN. A method for sensing gas in an oil-filled reservoir of electrical equipment, comprising providing a sensor device, immersing the sensor device in the oil-filled reservoir, allowing the gases emitted from the oil to interact with the one or more catalytic metal gate-electrodes, altering the gas as it contacts the catalytic metal gate-electrodes and altering the sensitivity of the sensor.

Abstract: A multi-gas sensor device for the detection of dissolved hydrocarbon gases in oil-filled electrical equipment. The device comprising a semiconductor substrate, one or more catalytic metal gate-electrodes deposited on the surface of the semiconductor substrate operable for sensing various gases, and an ohmic contact deposited on the surface of the semiconductor substrate. The semiconductor substrate comprises one of GaN, SiC, AlN, lnN, AlGaN, InGaN and AlInGaN. A method for sensing gas in an oil-filled reservoir of electrical equipment, comprising providing a sensor device, immersing the sensor device in the oil-filled reservoir, allowing the gases emitted from the oil to interact with the one or more catalytic metal gate-electrodes, altering the gas as it contacts the catalytic metal gate-electrodes and altering the sensitivity of the sensor.

Abstract: A multi-gas sensor device for the detection of dissolved hydrocarbon gases in oil-filled electrical equipment. The device comprising a semiconductor substrate, one or more catalytic metal gate-electrodes deposited on the surface of the semiconductor substrate operable for sensing various gases, and an ohmic contact deposited on the surface of the semiconductor substrate. The semiconductor substrate comprises one of GaN, SiC, AlN, InN, AlGaN, InGaN and AlInGaN. A method for sensing gas in an oil-filled reservoir of electrical equipment, comprising providing a sensor device, immersing the sensor device in the oil-filled reservoir, allowing the gases emitted from the oil to interact with the one or more catalytic metal gate-electrodes, altering the gas as it contacts the catalytic metal gate-electrodes and altering the sensitivity of the sensor.

Abstract: A multi-gas sensor device for the detection of dissolved hydrocarbon gases in oil-filled electrical equipment. The device comprising a semiconductor substrate, one or more catalytic metal gate-electrodes deposited on the surface of the semiconductor substrate operable for sensing various gases, and an ohmic contact deposited on the surface of the semiconductor substrate. The semiconductor substrate comprises one of GaN, SiC, AlN, InN, AlGaN, InGaN and AlInGaN. A method for sensing gas in an oil-filled reservoir of electrical equipment, comprising providing a sensor device, immersing the sensor device in the oil-filled reservoir, allowing the gases emitted from the oil to interact with the one or more catalytic metal gate-electrodes, altering the gas as it contacts the catalytic metal gate-electrodes and altering the sensitivity of the sensor.

Abstract: An apparatus for measuring partial hydrogen pressure in a gas stream is described. The apparatus includes a housing with micro-fuel cell sensor disposed therein. The sensor includes a sensing element having first and second gas diffusing electrodes spaced from one another with an acidic electrolyte disposed between the electrodes. A first gas permeable membrane separates the first electrode from an external gas stream. A second gas permeable membrane separates the second electrode from atmospheric air. Electrochemical charging of the first electrode occurs when hydrogen from a gas stream diffuses through the first membrane to react with the first electrode, while the potential of the second electrode remains unchanged. The potential difference between the first and second electrodes measured as current is identified to represent the sensor output.

Abstract: An apparatus and method are provided for continuously monitoring the operation of electrical equipment and preventing critical operational failures. The invention quantitatively determines the concentrations of gas and/or vapor (including water) components in an insulating fluid on a real time basis. An increase of one or more detected chemical components signifies an actual or potential electrical problem with the equipment. The preferred apparatus consists of a gas extractor, an infrared gas analysis instrument, and a gas diaphragm pump. Gas and water vapor components are extracted from the insulating fluid by permeating through a membrane in a gas extractor. The gas and/or vapor components are then brought into an infrared gas analyzer by the gas diaphragm pump. A quad detector in the analysis instrument identifies and determines the concentration of three specified gases and/or the vapor simultaneously.

Abstract: An apparatus for measuring hydrogen content and partial hydrogen pressure in gas streams and a method of modeling the sensor based on the characteristics of the sensor. The apparatus includes a housing with micro-fuel cell sensor disposed therein. The sensor includes a sensing element having first and second gas diffusing electrodes spaced from one another with an acidic electrolyte disposed between the electrodes. A first gas permeable membrane separates the first electrode from an external gas stream. A second gas permeable membrane separates the second electrode from atmospheric air. Electrochemical charging of the first electrode occurs when hydrogen from a gas stream diffuses through the first membrane to react with the first electrode, while the potential of the second electrode remains unchanged. The potential difference between the first and second electrodes measured as current is identified to represent the sensor output.

Abstract: An apparatus for measuring hydrogen content and partial hydrogen pressure in gas streams and a method of modeling the sensor based on the characteristics of the sensor. The apparatus includes a housing with micro-fuel cell sensor disposed therein. The sensor includes a sensing element having first and second gas diffusing electrodes spaced from one another with an acidic electrolyte disposed between the electrodes. A first gas permeable membrane separates the first electrode from an external gas stream. A second gas permeable membrane separates the second electrode from atmospheric air. Electrochemical charging of the first electrode occurs when hydrogen from a gas stream diffuses through the first membrane to react with the first electrode, while the potential of the second electrode remains unchanged. The potential difference between the first and second electrodes measured as current is identified to represent the sensor output.

Abstract: An apparatus for monitoring one or more gas components in a fluid wherein either a) a sample gas obtained from the fluid is enriched in at least one target gas which is to be subjected to analysis; b) at least one target gas which is to be subjected to analysis is separated from a sample gas obtained from the fluid; or c) both.

Abstract: An apparatus for measuring partial hydrogen pressure in a gas stream is described. The apparatus includes a housing with micro-fuel cell sensor disposed therein. The sensor includes a sensing element having first and second gas diffusing electrodes spaced from one another with an acidic electrolyte disposed between the electrodes. A first gas permeable membrane separates the first electrode from an external gas stream. A second gas permeable membrane separates the second electrode from atmospheric air. Electrochemical charging of the first electrode occurs when hydrogen from a gas stream diffuses through the first membrane to react with the first electrode, while the potential of the second electrode remains unchanged. The potential difference between the first and second electrodes measured as current is identified to represent the sensor output.