[thirty] During this configuration, the thermocouple junction is hooked up to your centre of a short heating wire, which is normally energised by a relentless present of about 5 mA, and the heat is removed at a level related to the thermal conductivity in the fuel. Thermocouples are quite simple http://stephencpakv.yomoblog.com/210109/about-temp-sensor-thermocouple