Functional PrincipleThe VCT160Y pirani gauge contains of a fine heated tungsten wire (also called a filament) suspended in a gas which will lose heat to the gas as its molecules collide with the wire and remove heat. If the gas pressure is reduced, the number of molecules present will fall proportionately, and the wire will lose heat more slowly. Measuring the heat loss is an indirect indication of pressure. The electrical resistance of a wire varies with its temperature, so the resistance indicates the temperature of wire.
The gauge is connected to a display controller with a 5-digit LED capable of Pa, Torr & mBar unit selection.