A thermocouple is a type of temperature sensor used to measure temperature. It consists of two wire legs made from different metals. These legs are welded together at one end, creating a junction. When the junction experiences a temperature change, it produces a voltage, which can be interpreted to measure temperature.
The principle behind a thermocouple's operation is known as the Seebeck effect. This phenomenon occurs when two different metals are joined together and exposed to different temperatures, generating a voltage proportional to the temperature difference.
Thermocouples are used in various industrial and scientific applications due to their wide temperature ranges, durability, and fast response time. They come in multiple types, each made from different metal combinations and suitable for different temperature ranges and environments. Their simplicity, reliability, and relatively low cost make thermocouples popular for temperature measurement in many fields.