How does a dissolved gas analyzer for transformer oil work?

A dissolved gas analyzer measures gases extracted from transformer oil and quantifies them, typically using gas chromatography or specialized sensors in online systems. Oil is degassed in a controlled chamber, the released gas mixture is separated and measured, and concentrations are reported for key gases. Online systems automate sampling and trending, generating alarms when gas rates exceed thresholds. Accuracy depends on calibration, extraction efficiency, and correct compensation for temperature and oil type.