A thermoelectric device used to make accurate measurements of temperatures, especially high temperatures. It consists of a circuit having two wires of different metals or metal alloys welded together. A temperature gradient across the junction of the wires gives rise to an electric potential by the Seebeck effect. This potential varies with the strength of the temperature gradient and can be measured by a voltmeter. Thermocouples can also be used to generate small amounts of electricity for powering other devices.