The ability to measure temperature has created a mountain of opportunities, which have consequently shaped the world we live in today.
From facilitating the cooking of food, to complex engineering and medical science, monitoring temperature lies at the heart of these operations.
So… how is temperature measured?
Thermocouple Wire Types Explained
Thermocouple Wire Types
The type of thermocouple wire refers to the combination of materials, or alloys, used. There are several established and commonly used types of wire.
Type K is one of the most popular types of thermocouple wires. It consists of a positive nickel/chromium alloy leg and a negative nickel/aluminium leg. It can withstand a vast temperature range (from -200°C to 1250°C), making it suitable for many applications in a variety of industries. This is furthered by type K being an affordable option for many when compared with the Platinum based Type R and Type S thermocouples.
Type J is another common wire type, made from a positive iron leg, and a negative constantan (copper/ nickel alloy) leg. It does have a smaller temperature range than type K – ranging from 0°C to 750°C – meaning it has fewer applications. It may typically be seen in manufacturing operations or aircraft.
With a positive copper leg, and negative constantan leg, type T can be used in temperatures from -250°C to 350°C. Due to its capabilities in cold conditions, type T may measure temperature in freezers.
Type E consists of a positive nickel/ chromium leg and a negative constantan leg. Type E has a temperature range of -200°C to 900°C, and is particularly sensitive to measuring temperatures.
Type N is a relatively new thermocouple wire which arguably rivals the popular type K due to its superior repeatability characteristics around 400°C. It features two nickel alloy legs, and can withstand temperatures from -270°C to 1300°C. Type N may be used for measuring engine exhausts, among other applications.