Abstract
In order to disseminate distributed energy systems an autonomous abnormal diagnosis is imperative. The purpose of this study is to develop the abnormal diagnosis method using the fieldbus technology, which makes it possible to share much information of field devices. At the first stage, the authors constructed a experimental apparatus of a heat exchanging process and a measurement and control system with fieldbus devices and developed two types of two types of the abnormal diagnosis method for the air retention to the shell of the heat exchanger : the monitoring of the overall heat transfer coefficient as the representative process parameter and the monitoring of the correlation between the condensing pressure and the condensing temperature as a simpler method. The experimental results show their effectiveness and features.
