If the precise 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 unfortunate circumstances such as for example soiled media, abrasive ingredients and sludge when used in wastewater treatment plants, brackish and wastewater tanks or even digester towers, impose special requirements on the look of a submersible pressure transmitter. One of the main requirements on a submersible pressure transmitter is to obtain the lowest possible susceptibility to contamination or build-up of the pressure sensor by optimizing its design. This is exactly why the typical design of a pressure transmitter with narrow pressure ports isn’t used within level probes since 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 very low susceptibility to contamination. However, continuous operation in soiled media can lead to sticking of dirt particles on the stainless steel diaphragm. To obtain the highest accuracy and fastest response times in the event of level change, the thickness of the stainless steel diaphragm has already been minimised ex factory to just a couple microns. Therefore, cleaning of the diaphragm should be completed with caution. Always avoid using Looming or edged tools. It is also 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 though it seems to be purely superficial, leads to significant losses in the accuracy of level measurement. Violent of the diaphragm often shifts the zero point of the pressure measurement in the internal electronic measurement system and additionally 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, can’t be considered a reliable measuring instrument any longer. Thus, complete replacement of the damaged instrument is absolutely necessary.
Please find more info on this topic on our information platform ?Hydrostatic level measurement?