Two new oil filled 10MV·A transformers 44kV/4.16kV were installed connected to the same source. After two years DGA indicated very high hydrogen levels in one of the transformers (>20,000ppm). Methane>1900, Ethane>200, Carbon Dioxide>1000. A Radio Interference Voltage test by the transformer...
How can I tell if a surge arrester is staion class or intermediate class? Made by Ohio Brass type GP, series 3, rated 39kV, 34.5 inches tall, porcelain, 92 pounds.
