Relative pressure / absolute pressure method

relative or absolute pressure

The relative or absolute pressure method permits a compact test set-up and is characterized by good operating reliability and a wide measurement range. In this case, the test specimen is placed under pressure and the pressure differential is determined over the set time.

With the relative pressure method, the differential to the ambient pressure is measured. This is why this is known either as overpressure testing, if the test pressure is greater than the ambient pressure, or vacuum testing if the pressure is lower than the ambient pressure.

When using the absolute pressure method, the test pressure is determined relative to the absolute zero point (absolute vacuum). The resolution depends on the test volume and the test pressure. This method permits a resolution of 1 Pa.