Need help finding the right pressure sensor

Hi I am tying to design a system that measures fluid pressure. I need the sensor to have a small form factor and definitely need to be submersible. (I need to measure 0~50mmHg but the specs don’t seem to have a problem with that range) I see many pressure sensors available (for e.g. MPX5010DP), but can’t make out if they are submersible. Nor can I tell the difference on how to differentiate them. May I ask for guidance on this issue? Thank you very much.

MPX5010DP is not submersible , you have to design for this part to be in a water tight enclosure and the ports to be able to be sealed outside the enclosure so the do not leak into the enclosure. that is true for most sensors like these.

Thank you for the prompt response. I wonder though, if the sensor does not come into contact with the fluid, how does it measure pressure? I’m interested in measuring hydrostatic pressure. Are you aware of any products at all that can do this?
I’m a newbie in this forum, so not sure if i can post links here, but would you know what this person did to make the sensor submersible?
Pressure Sensor Based Water level Monitoring and Printing Arduino Serial - YouTube
Thanks again.

The sensor in the referenced video is not submerged; it is measuring air pressure in the connected tube.

Small, low- pressure sensors of that sort are typically compatible with air and dry, inert gases; media compatibility beyond that being the exception rather than the rule. Pressure sensors compatible with water or other hostile media tend to have threaded connections and higher measured pressure ranges than the 50mm Hg mentioned. Unfortunately, while media compatibility would be a nice thing to be able to select for parametrically, it’s not at option at the present time on the DK site.

Thank you for the response. I am ok with larger pressure ranges. Since there is no filter in DK site as you mention, can you point me to just one sensor model that is submersible? I will take it from there on.

you will have to place the sensors and the electronics in an enclosure that has ip68 or 69 sealed so the enclosure is water proof . this maybe what you will have to look at.

Hi sunuk,

For measuring low level pressures in liquids, one doesn’t need a submersible sensor because it is not placed directly in the liquid. The preferred method is to attach a tube to a sensor and insert the tube (as shown in the video you referenced) with the end facing down, so as to not let any air out of the tube. With this arrangement, the pressure of the air in the tube will be equal to the pressure of the liquid at the bottom of the tube. Thus, the air pressure in the tube allows measurement of the liquid pressure while isolating the liquid from the sensor itself.

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