An E thermocouple is a type of thermocouple that is commonly used to measure temperature in a wide range of applications, including in industrial processes, scientific experiments, and HVAC systems. The E in E thermocouple refers to the specific types of metal alloys used in the construction of the thermocouple. An E thermocouple consists of two different types of metal wires, usually made of nickel-chromium (NiCr) and copper-nickel (CuNi), that are welded together at one end to form a sensing junction.