Differential pressure gauge
A sensor for measuring differences in pressure between two systems, one of which is used as reference.
Manometer
Mercury pressure gauge
Spiral pressure gauge
It can be a very simple device made up of a U tube out containing a coloured liquid which makes it possible to see the pressure difference between a closed enclosure, e.g. a glove box, and the outside world. In this case, one end of the U tube is connected to the enclosure and the other end is open to atmospheric pressure.
