What type of signal does a thermocouple produce?

A thermocouple produces a thermoelectric signal due to the Seebeck effect, which is the basis of its operation. When two dissimilar metals are joined at two junctions and subjected to a temperature gradient, a voltage (thermoelectric signal) is generated that is proportional to the temperature difference between the junctions. This phenomenon allows thermocouples to measure temperature accurately.

The Seebeck effect relies on the principle that the movement of charge carriers within the metals responds to thermal energy, resulting in an electromotive force (EMF) that can be measured as a voltage signal. The type of signal generated is continuous and analog in nature, allowing for a range of temperature measurement rather than just discrete values, which is why it's critical in temperature sensing applications.

While thermocouples do output a type of voltage signal that can be used in analog systems, the terminology that accurately describes the nature of this signal is the thermoelectric signal resulting from the Seebeck effect. Other forms of signals, like digital signals or resistance signals, do not pertain to how thermocouples function or the type of output they provide.