Nickel chromium copper nickel (constantan) thermocouple wire (type E)
Nickel chromium copper nickel thermocouple (E-type thermocouple), also known as nickel chromium constantan thermocouple, is also a kind of low metal thermocouple. Its positive electrode (EP) is nickel chromium 10 alloy with the same chemical composition as KP. The negative electrode (EN) is copper nickel alloy. Its nominal chemical composition is 55% copper, 45% nickel and a small amount of cobalt, manganese, iron and other elements. The use temperature of the thermocouple is - 200~900 ℃.
Type E thermocouples have the largest electromotive force and the highest sensitivity of all thermocouples. They should be made into thermopiles to measure small temperature changes. It is insensitive to corrosion in high humidity atmosphere, and should be used in high humidity environment. The E-type thermocouple also has the advantages of good stability, superior oxidation resistance to copper constantan, iron constantan thermocouples, and low price. It can be used in oxidizing and inert atmospheres and is widely used by users.
Type E thermocouples cannot be directly used in sulfur and reducing atmospheres at high temperatures, and their thermoelectric homogeneity is poor.