A thermocouple is a kind of battery made by joining two dissimilar metals together where a small voltage is generated by the difference between teh metals. The voltage gnerated changes with temperature. To make a thermocouple temperature sensor out of thermocouple extenision wire, strip the insulation back a little and make an electrical connection between the two wires. The more reliable your connection, the more reliable the thermocouple. Welding is the best way to form a reliable thermocouple. A resistance welding machine (spot welder) can be used (with practice), and TIG welding works nicely too.

Learn the importance of monitoring concrete-curing temperatures and the potential consequences of not doing so – from presenters Hoskin Scientific and Davroc & Associates.