In an apparatus for detecting gas components in the oil in an oil-filled device, which comprises a gas-storing chamber being provided at an oil-filled device containing an insulating oil through a gas-permeating material capable of separating gas components from the insulating oil, a gas calibration...http://www.google.com/patents/US4444040?utm_source=gb-gplus-sharePatent US4444040 - Method and apparatus for detecting gas components in oil in oil-filled device
