You find a liquid-filled transformer at a substation with its pressure relief device deployed and dark oil leaking. A DGA (Dissolved Gas Analysis) reveals high levels of acetylene. What does this indicate?
Answers
AHigh-energy electrical arcing has occurred inside the transformer tank
BThe transformer is operating normally but got slightly warm
CThe oil needs to be topped off due to evaporation
DWater has entered the tank causing rust
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