What faults can be detected using DGA transformer oil analysis?

Dissolved Gas Analysis can indicate overheating of oil or paper (thermal faults), partial discharge, arcing, and high energy electrical faults. Key gases include hydrogen, methane, ethane, ethylene, acetylene, and carbon oxides. Patterns and ratios help differentiate fault types, while trending shows whether a condition is stable or accelerating. DGA is most powerful when you compare current results to historical results and loading history.