Thermocouples | A thermocouple is a sensor that measures temperature.
It consists of two different types of metals, joined together at one
end. When the junction of the two metals is heated or cooled, a voltage
is created that can be correlated back to the temperature.
There are many different types of thermocouples. Each of the thermocouple types
are given a coding letter to denote each of the alloy combinations. The
most common code letters are K, J, T and N. Other types include R, S,
E, B, C, G and W.
Each type of thermocouple has
its own alloy pair which is carefully selected and calibrated to meet
the international standards with which we must comply. The standard that
governs thermocouples in the UK and Europe is BS EN 60584 and ASTM
Standard E230, which provides specifications for the common industrial
grades, including the letter designations used for each type of
thermocouple. These standards ensure accuracy and consistency in
temperature measurement.
A thermocouple consists of a welded ‘hot’
junction between two dissimilar metals. These are usually wires with a
reference junction at the opposite end.