Hi,
I’m trying to find an arduino compatible vacuum sensor with a range of around -1 to 0 bar and capable of handling water.
Seems simple but everything in that ballpark is either; dry air only/absolute pressure/differential pressure/very expensive industrial stuff… which is not going to work for me.
Anyone have some ideas or recommendations for something suitable?
I use which were once Motorola, now NXP. Look here for a start: Integrated Pressure Sensor (0 to 10 kPa) | NXP Semiconductors You can select from what they show then find a distributor to sell them to you.
Below zero? I wonder what your application is for this.
Hi, @bran
Are we talking gauge pressure or absolute pressure measurement?
What is your application?
Thanks.. Tom... 
@gilshultz , @LarryD Thanks for the tips, unfortunately I’m based in South Africa so electronics distributors carry limited stock and ebay/amazon are not available. I can order, but shipping is pretty expensive from places like Farnell/Mauser/Digikey ect.
@TomGeorge, @Rintin I want to measure the suction pressure of a pump. It’s a positive displacement pump and it’s pulling water through a filter, so the pressure can go down very low when the filter gets fouled.
I’d like gauge pressure. I could use absolute pressure but then I’d need a second sensor to measure atmospheric and calculate the pump vacuum.
Thank you, that's what we needed to know.
It would be better to use a differential pressure sensor and measure the pressure difference either side of the filter.
Tom...
Some clear plastic tubing would make a nice manometer, just fill it with water to the middle then measure the difference between the columns. Use a measuring device calibrated in the measurement units you want such as Inches, cm, ..etc. You can put opto sensors at the lower limit for an alarm. To keep it from evaporating put a few drops of oil on each side, I use dmineral oil.
This topic was automatically closed 180 days after the last reply. New replies are no longer allowed.