Gaugeviitepaine

Gaugeviitepaine, or gauge reference pressure, is the reference baseline used when measuring pressure with a gauge. It defines the pressure against which the process pressure is compared, and the gauge reading represents the difference between the measured pressure and this reference.

In most practical cases, the reference pressure is atmospheric pressure at the measurement location. When P_ref equals ambient atmospheric pressure, gauge pressure equals the absolute pressure minus atmospheric pressure (P_gauge = P_abs − P_atm). If the reference is a different pressure, such as in a closed system or a differential sensor, the gauge reading reflects P_proc − P_ref rather than a simple atmospheric difference.

Gauge pressure is distinct from absolute pressure, which is measured relative to a perfect vacuum. Because of this, gauge readings can be negative if the process pressure falls below the reference pressure. The concept is important for correctly interpreting readings and for calibration, especially in systems where the reference pressure may vary or where non-atmospheric references are used.

Common units for gauge pressure include pascals, kilopascals, bar, and psi. When reporting a gauge measurement, it is standard to specify the reference pressure, typically “gauge pressure relative to atmospheric pressure” or a stated alternative reference.

Applications span automotive tires, HVAC and process industries, pneumatic and hydraulic systems, and instrumentation. For safety-critical or sealed systems, absolute or differential pressure measurements may be necessary to avoid misinterpretation of gauge readings. See also gauge pressure, absolute pressure, differential pressure, and manometer.