Serveron – Acetylene: Hot Metal Gases
Serveron – The Importance of Measuring Oxygen In DGA
Serveron – Hour by Hour Changes, Catching a Developing Fault
A Qualitrol Serveron TM8 mutli-gas DGA monitor was being used to monitor a single phase 336 MVA, 500/230 kV autotransformer. This transformer was placed into service in 1979. The transformer is known to have gassed in the past and so base levels of hydrocarbon gases are as high as 100ppm. At 1:00am on June 23, 2014, the TM8 alarmed for Rate-of-Change increases in concentration of Ethylene (C2H4) and Methane (CH4) both of which had been elevated but stable for several months. Over the next 5 days the operator kept the transformer under load for operational purposes and carefully monitored all gases. When Acetylene (C2H2) climbed to an actionable level (10ppm) the transformer was taken off-load.
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