The ME2-CO electrochemical carbon monoxide gas sensor operates based on the principle of electrochemistry. It utilizes the electrochemical oxidation process of the carbon monoxide gas to be measured at the working electrode potential in an electrolytic cell. The current generated by the electrochemical reaction of the gas to be measured is proportional to its concentration and follows Faraday's law. The concentration of the gas to be measured can be determined by measuring the magnitude of the current.