K Type Thermocouples

Written by Nicholas Kamuda
Bookmark and Share

K-type thermocouples are the most commonly used type of thermocouple in handheld temperature measurement devices. They are included in only a few professional thermometers and also used in a variety of other types of electronics (such as digital multimeters). Though there are many different types of thermocouples (identified by the metals that they use), K-type thermocouples are great general-purpose thermocouples that are suitable for many applications.

In general, thermocouples are popular because they are inexpensive to produce and are rugged enough to be used in handheld electronics. The two main components of most thermocouples are a pair of dissimilar metals that when heated create a voltage over the junction between the two metals. The voltage that is created is proportional to the temperature of the metals.

Only a few IR thermometers include thermocouples as a method of measuring the internal temperatures of solids and liquids. A few IR thermometers that don't include a built-in thermocouple may have a port for connecting an external thermocouple. Most thermometers with this option accept either T or K type thermocouples.

Basic Features of K Type Thermocouples

K thermocouples use Nickel Aluminum and Nickel Chromium as the two metals. Both alloys are common, and the pairing of the two can produce measurable voltages from minus 200° to 1,200° Centigrade. Other types of thermocouples may have strange byproducts, such as the magnetic transformation of J-types at high temperatures, but K-types have a stable design that has an even sensitivity at any temperature.

Bookmark and Share