Condition monitoring of high voltage transformer oils using optical chromaticity

The motivation for the present contribution was to produce a cost effective, convenient system for the optical monitoring of degraded high voltage transformer oils using the chromaticity of polychromatic light transmitted through the oil. The technique uses readily available and portable instrumentation. Examples of results for typical oil samples have been obtained with the technique and comparisons made with the conventional technique of Colour Index. It is shown how the chromatic technique can supplement the Colour Index approach to provide additional information about changes in the transformer oil, such as the presence and extent of solid micro-particles.