Sayad - A.I. I Co
Nanjappa - Mapna Co
Sayad - Tavanir Co
Hamidi - Tavanir Co

The research activities of chemical engineering led to excellent advancement on dissolved gas analysis of power transformers insulating oil. It has become more p opular in power utilities for early detection of internal problems of power transformers such as oil degradiation, arcing, orona, tehrmal faults, aging of insulation paper, overheating of current carrying parts, transformer core, etc. to rectify faults and analyse results of gas chromatography, the excellent work of IEC-599, 1976 is adopted, and is further modified for analyzed adtions with expert system as explained in later in this paper, namely knowledge base, operation, design, maintenance workbase etc.. In future we are certain that on-line monitoring system with dissolved gas analysis expert system will definitely control the process of power transformer loading as well as improve long life of power transformers.