Dissolved Gas Analysis

Dissolved Gas Analysis (DGA) is used to determine the concentrations of specific gasses dissolved in the oil.  The relative ratios of these gases may be used to diagnose certain operational problems with the transformer, which may or may not be associated with a change in a physical or chemical property of the insulating oil.  The dissolved gasses in the oil are equilibrated in the two phases before being introduced into the gas chromatographer.  The various gas components are separated and detector at the end of the column measures and records the levels of components at predetermined retention times.  The sampled peak areas at the programmed retention times are compared and the results quoted as ppm.