Expert systems vs. human expert

Expert systems have in recent years become an integral package of many online monitoring systems and diagnostic test equipment sold to transformer manufacturers, service providers and end users. They are also commonly used in oil laboratories for providing standardized reports with recommendations on dissolved gas analysis and oil quality tests results. This article discusses briefly the limitations of algorithms typically used in expert systems and in more detail their shortcomings. The article also provides examples of why expert systems have not and cannot replace the final review and assessment of the test results by a human expert considering that reports produced, automatically, by such expert systems will not cover the complex facts when important and costly decisions have to be made