What is a Thermocouple? Thermocouple Sensors to your Specifications
What is a Thermocouple?
A thermocouple is a simple device that is used to measure temperature. Thermocouple sensors are made from two wires joined (welded) together to form a measuring junction (also known as a hot junction). This junction is usually enclosed in a metal sheath and is inserted into the medium where the temperature is to be measured. The opposite end of the two wires are also (effectively) joined at a point known as the cold junction.
How does a thermocouple work?
As the temperature at the hot junction changes, it creates a thermal gradient between the hot and cold junctions which generates an electron flow and a resultant electromotive force (EMF), measured in Millivolts. The voltage measured at the ends of the conductors is a function of the temperature difference along the conductor length. This effect was discovered by TJ Seebeck in 1822 and is known as The Seebeck Effect.
When used with a temperature instrument, the cold junction is electronically referenced to 0ºC and a formula is applied to the millivolt signal, which is then be converted to °C or °F, using instrumentation. For a more detailed explanation of how a thermocouple works, please see our Thermocouple Theory page.
Thermocouple Sensors - Custom Built Thermocouples to your Specifications
We are the largest manufacturer of thermocouple sensors in Europe. Having an enormous range of components in stock means we can make virtually any sensor you specify. We can ship custom built thermocouples typically within 5 days or sooner.
Thermocouples Rugged sensors, ideal for most applications. Vast choice of terminations e.g. pot seals, cables, connectors, heads etc.Swaged Tip
Thermocouples Fast response thermocouples ideal for industrial and other applications. Miniature
Thermocouples Ideal for precision temperature measurements where minimal displacement and a fast response is required. Heavy Duty
Thermocouples For industrial applications such as furnaces, kilns, ovens, boliers, flues etc. Many types of sheath material available. High Temperature Thermocouples Various thermocouples specifically for high temperature applications. Wide choice of sheath materials and terminations. General Purpose
Thermocouples A wide range of thermocouples to suit many applications. Hand held, surface, bayonet, bolt, patch styles etc. AMS2750 Approved
Thermocouples Calibrated thermocouples designed to meet the high quality and accuracies demanded for heat treatment and vacuum furnace applications Industrial Vacuum
Thermocouples Ceramic sheathed calibrated thermocouples designed specifically in vacuum furnace applications with very low leak rates ATEX/IECEx Approved
Thermocouples A large range of thermocouples with a variety of terminations such as pot seal, terminal heads etc.
There are several different thermocouple calibration types (K Type thermocouples, J Type, T Type, N Type, Type R and Type S) each with different characteristics and covering various temperature ranges. Type K is one the most popular thermocouples used in industrial applications, due to its versatility and wide temperature range, T type thermocouples are generally preferred in applications below 0ºC and Type R thermocouples are preferred in furnace thermocouple applications. A detailed list of the different thermocouple types, thermocouple colour codes and other characteristics can be found here.