Thermocouple gauge is a device used to measure low vacuum.
Working of a Thermocouple Gauge
In Thermocouple Gauge a filament is heated by passing constant current through it.When gas molecule interact with filament heat is carried away.Therefor the temperature is directly depended on the pressure in the chamber.The higher the pressure the more molecule interact with the filament and more heat is taken from it.The temperature change in the system is monitored with the help of a thermocouple where the generated voltage is depend on the temperature of the filament. When the filament loses heat by interacting with gas molecules,the change of voltage in thermocouple is detected with the help of a volt meter. Therefor the measured voltage can be easily converted into pressure units.
Thermocouple Gauge Working – Animation