thermovoltmeter

thermovoltmeter

[¦thər·mō′vōlt‚mēd·ər]
(engineering)
A voltmeter in which a current from the voltage source is passed through a resistor and a fine vacuum-enclosed platinum heater wire; a thermocouple, attached to the midpoint of the heater, generates a voltage of a few millivolts, and this voltage is measured by a direct-current millivoltmeter.