What does thermocouple mean?
A thermocouple is a device for measuring temperature that uses two different conducting materials joined together. The junction between the conductors generates a small voltage when its temperature differs from that of the other ends, allowing a precise, continuous electrical signal to be produced. Thermocouples are widely used in industrial furnaces, engines, laboratories, aerospace equipment, and domestic appliances, where they must be durable and capable of operating over a wide range of temperatures. Different combinations of metals are designated by types such as K, J, or T, each with particular temperature ranges and accuracy characteristics. The word is primarily technical, but it describes a familiar principle behind many temperature-control systems. Unlike an ordinary thermometer, which presents a temperature directly, a thermocouple usually supplies a voltage to a meter, recorder, or controller. It is especially useful where rugged construction and reliable continuous measurement are important.
nounA thermocouple is a temperature sensor made from two dissimilar conductors joined at a junction. It produces a measurable voltage that changes with the temperature difference between the junction and a reference point.
- An electrical temperature sensor consisting of two dissimilar conductors joined at a junction, producing a voltage related to the temperature difference.
"The furnace controller used a thermocouple to monitor the temperature of the chamber."
"Engineers attached a thermocouple to the engine cylinder to measure its operating temperature."
"The laboratory calibrated each thermocouple against a certified reference temperature before beginning the measurements."
The standard plural is “thermocouples.”
"Several thermocouples were connected to the data logger."
A thermocouple turns a temperature difference into an electrical signal, making the invisible measurable.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does thermocouple come from?
Thermocouple combines thermo-, from the Greek thermē, meaning “heat,” with couple, meaning a pair, referring to the two conductors joined together. The expression developed from the term “thermoelectric couple,” used in the nineteenth century for the arrangement of dissimilar metals that produces an electrical effect when heated. The word couple came through Old French from Latin copula, a bond or tie.
How thermocouple is actually used
Chiefly technical, especially in engineering, manufacturing, automation, and scientific measurement. The term usually refers to the sensor and its signal-producing junction rather than to the display or control system connected to it.
Easily confused with thermocouple
A thermocouple generates a voltage from the temperature difference between two dissimilar conductors, whereas a thermistor changes electrical resistance as its temperature changes.
A thermometer directly indicates or measures temperature, while a thermocouple usually converts a temperature difference into an electrical signal for instrumentation.