Difference in Absolute and Relative Pressure Gauge


Thread Starter


good day everyone,

what is the reading in my absolute pressure gauge and my relative pressure gauge if i measure lets say a 2 bar pressure? its just that i want to know their difference in reading when measuring same pressure.

could you help me please.
thank you
If you are measuring 2 bar(A) pressure using an absolute pressure gauge and a relative pressure gauge, readings will be:

Absolute Pressure gauge: 2 bar
Relative Pressure gauge: 1 bar (Considering 1 bar atmospheric pressure)

At any point, readings on the Absolute pressure sensor = (Relative pressure sensor reading+ Atmospheric pressure)
All pressure measurement is differential, that is, the measurement is made relative to, or with respect to, a reference pressure.

A gauge or gage pressure measurement references local atmospheric pressure. A tire pressure gauge makes a gauge pressure measurement references atmospheric pressure.

An absolute pressure measurement references absolute zero, a hard vacuum, or as close to absolute zero as can be managed. A barometer makes an absolute pressure measurement referencing a vacuum inside the barometer.

A differential pressure measurement references second pressure source, so a differential measuring transducer/transmitter has two ports, where the high low side pressure references by low side pressure; 'subtracting' the low side from the high side pressure to report a differential pressure.
Absolute measures from absolute zero pressure (i.e. total vacuuum; "outer space"), i.e the measurement includes atmospheric pressure.

Relative measures the difference between two pressures. One is typically the reference, which is sometimes atmospheric pressure (i.e. open to "air").