3. Pressure measurement control systems

Level measurement using relative or differential pressure transducers is a manometric or hydrostatic measurement, and therefore does not provide the "true" height (see article [R 2 010] Level measurement and control – Introduction). It does not concern the volume capacity of containers, but the mass capacity. The quantities to be used are pressure or, in a pinch, the column height of a specified liquid (e.g. millimetre of water column).

The technological description of pressure measurement devices can be found in articles [R 2 040]