Temperature sensing and control is a critical requirement in applications like furnaces, boilers, HVAC and in industrial processes like chemical, petrochemical, oil & gas, and food processing/manufacturing.
Thermocouples are widely used in these applications for temperature sensing. They work on the principle of Seebeck effect, where two different metal wires are joined together, and this junction generates a voltage proportional to the temperature. The most common thermocouple types or thermocouple calibrations available are B, E, J, K, N, R, S, T & C. Each of these types have a specified temperature range in which they can be used. Thermocouples are available in various form factors like immersion probes, surface probes, air probes, bulkhead probes etc. Thermocouple wires, thermocouple extension wires and thermocouple connectors are important accessories that are used along with thermocouples.
Thermocouple wires are used to connect the sensor to the measuring instrument or temperature controller/transmitter. Thermocouple extension wires are used to extend the distance between the sensor and the measuring instrument or controller/transmitter. Thermocouple connectors are used to provide a secure and reliable connection between the thermocouple wires/extension wires and the measuring instruments. Thermocouple connectors are available in standard and miniature versions with 2-terminal connectors being the most used.
Application temperature, degree of accuracy in measurement, resistance to harsh environments, thermocouple wires, thermocouple extension wires and thermocouple connectors are the key factors based on which a thermocouple type is selected.