Dissolved Gas Analysis – What do the gasses tell us?

Gassing of insulating oil is a common occurrence in an operating transformer. However, each gas has a story to tell. In terms of risk, each gas has a personality. The oil (a complex hydrocarbon), when stressed with heat or electrical activity will break down into simpler gases. These are also known as hydrogen, carbon monoxide, carbon dioxide, methane, ethane, ethylene and acetylene. Although oxygen and nitrogen may be identified in the analysis, they are not directly linked to a fault.