“Most recent failures due to corrosive sulphur are related to the formation of copper sulphide deposits in and on the surface of winding cellulosic paper. The test method uses a copper conductor, wrapped with one layer of paper, immersed in the oil and heated to evaluate the capability of the oil to yield copper sulphide and transfer it to paper layers. The growth of copper sulphide on bare copper may cause the presence of conductive particulates in the oil, which can act as nuclei for electrical discharge and may lead to a fault.”
(Quote from IEC 62535)
What method is used to analyze the sample?
IEC 62535
How do you interpret the results?
IEC 62535
What do the results indicate?
“In the case where a positive result is found for copper, or paper, or both, the oil is reported as potentially corrosive. If, for both samples, a negative result is obtained for both copper and paper, the oil shall be reported as non-corrosive.” (Quote from IEC 62535)