In principle, all differential pressure sensors are suitable for the flowmetering of dry air. They are selected according to the drop in pressure at the aperture and the magnitude of the static pressure in the flow channel. With condensed gases and liquids only sensors which are suitably protected against the relevant medium can be used.
The sensors are used to determine the amount of media and flow velocity and to monitor the flow. Possible areas of applications include:
- Filter monitors
- Gas meters
This type of application aims to determine the degree of soiling on a filter in order to trigger a warning function or initiate a replacement as required. Differential pressure sensors are used here to determine the drop in pressure across the filter (bypass application). The critical variable is the system pressure (in the filter inlet and outlet) which the sensor has to withstand against the external pressure. This variable is especially critical with a one-sided drop in pressure and with differential low pressure sensors.
Depending on the system pressure all differential pressure sensors within a range of 100 mbar to several bar are suitable for filter monitoring.
The control and measurement of the gas flow is required in many industrial systems, up to and including hot water storage facilities.
Extremely sensitive differential pressure sensors are needed to measure the flow of such gases.