Cold junction compensation

Cold junction compensation (CJC) is a technique used to correct the measurement of temperature using a thermocouple. A thermocouple is a device that consists of two different conductors joined at one end, which generates a voltage in response to a temperature difference between the two conductors. The voltage generated by the thermocouple is known as the thermoelectric voltage or the Seebeck voltage.

The temperature at the point where the two conductors of the thermocouple are joined is known as the reference junction or cold junction. In order to accurately measure temperature using a thermocouple, the temperature of the reference junction must be known. This is because the thermoelectric voltage generated by the thermocouple is a function of the temperature difference between the two conductors.

Cold junction compensation is used to accurately measure the temperature of the reference junction and correct the measurement of temperature using a thermocouple. There are a variety of methods used to perform cold junction compensation, including the use of reference thermocouples, thermistors, or temperature-sensitive resistors.

Overall, cold junction compensation is an important technique used to accurately measure temperature using thermocouples and is essential for ensuring the accuracy of temperature measurements in a variety of applications.