What is a thermocouple?

A thermocouple is a sensor used to measure temperature. It is a very popular sensor type because of its relatively low cost, interchangeability, wide measurement range, and reliability. Thermocouples are widely used in all industries - from factory automation and process control to automotive, aerospace, military, power generation, metal fabrication, medical sciences and countless other sectors. Equipped with standard connectors, they are interchangeable and easy to obtain. The sensing side of the sensor can be very simple (e.g. two metal wires twisted together) or encased in a robust probe for use in harsh industrial environments.

 

Selection of the right thermocouple for your application

Various factors must be taken into account when selecting the right sensor for your measurement:

• What are the highest and lowest temperatures that need to be measured?
• What is the budget?
• What precision is required?
• In what kind of atmosphere should the sensor be used (oxidizing, inert, etc.)?
• What usable sensor lifetime is required?
• What response time is required (how fast does the sensor need to respond to temperature changes)?
• Should the thermocouple be used intermittently or continuously?
• Will the thermocouple bend or bend during its lifetime?
• Is it immersed in water? If so, to what depth?
• Should the temperature be measured on the surface and/or in the medium?

 


Based on the answers to these questions, you should be able to select the most appropriate sensor(s) for your application.