Voltage spectral structure of the thermocouple with temperature dependent wires

The article presents a study of the origin extra harmonics in frequency spectrum thermocouple output signal when being heated by sinusoidal waveform current. It is natural to have first harmonic, which arises according Ohm’s law, as product current and total resistance junction conductors, well Peltier, Thomson effects, presence second caused heating conductors. fact that third higher arise conductors thermally dependent was identified. analytical dependence resulting voltage across terminals function junction, voltages due effects Joule, Seebeck, Peltier Thomson, established. Based on analysis obtained experimentally spectra terminal thermocouple, an assumption made about nature heats wires thermocouple. Recommendations are given reduce influence first, harmonics, uninformative, separate informative used get response Keywords: response; thermocouple; EMF; spectrum; resistance;