This project deals with the study of an old analyzer which is very expensive and used for estimation of strategic elements. The analyzer is working on DOS (Disk Operating System) and old electronic hardware which are obsolete in the market. Therefore, the old hardware and its frequent problems, it was planned to upgrade the analyzer with latest electronic hardware and GUI (Graphical User Interface) software compatible to latest windows operating system. Catalyst temperature of the analyser is one of the important parameters which need to be measured and controlled. For this purpose, analyser was using old PID board which was obsolete and not working. As a part of under graduation the PID board is to be replaced with latest PID controller. Suitable PID Controller is to be selected and configured for attaining the temperature of 350°C.