If the specific pressure sensor design of the submersible pressure transmitter or level probe is selected to gauge the filling levels, this can indicate that the probe is used under environmental requirements which may cause failure of common level sensors.
The most adverse conditions such as for example soiled media, abrasive ingredients and sludge when found in wastewater treatment plants, brackish and wastewater tanks and even digester towers, impose special requirements on the design of a submersible pressure transmitter. One of the main requirements on a submersible pressure transmitter would be to obtain the lowest possible susceptibility to contamination or build-up of the pressure sensor by optimizing its design. This is exactly why the normal design of a pressure transmitter with narrow pressure ports is not used within level probes because it would have a tendency to clog in such applications.
The look of the submersible pressure transmitter and its own pressurised sensor diaphragm is optimised in order to achieve suprisingly low susceptibility to contamination. However, continuous operation in soiled media can lead to sticking of dirt particles on the stainless steel diaphragm. To get Instantly and fastest response times in case of level change, the thickness of this stainless steel diaphragm is already minimised ex factory to just a few microns. Therefore, cleaning of the diaphragm should be carried out with caution. Always stay away from sharp or edged tools. Additionally it is strongly advised not to use the popular screwdrivers or pens.
If cleaning of the sensor diaphragm is necessary, then rinse it utilizing a weak water jet or clean it carefully using compressed air. Damage of the diaphragm because of denting or notching, even if it seems to be purely superficial, leads to significant losses in the accuracy of level measurement. Deformation of the diaphragm often shifts the zero point of the pressure measurement in the internal electronic measurement system and also distorts the output signal linearisation which has been adjusted ex works to the undamaged diaphragm. Thus, the submersible pressure transmitter with damaged diaphragm generates falsified measurement of the existing filling level and, therefore, cannot be considered a trusted measuring instrument any longer. Thus, complete replacement of the damaged instrument is completely necessary.
Please find further information with this topic on our information platform ?Hydrostatic level measurement?