[Water Level] H ow to measure the water level?

@chris how are you powering this? Battery or AC adapter?
I see that it takes 7mA current, is that all time? Is there a power saving mode? If not, I can drive it from arduino IO pin, switch on once every 2 min and send reading to OH. But how long before it settles after powered on?
I need to check data sheet but I thought you may have hands on info already.

I use an AC supply. Itā€™s connected to a irrigation system I built which is in a log cabin down the garden. I think it probably outputs 12v supply to the pressure sensor board which is probably about 20 or 30 ft away - I then have the 5v regulator at the sensor to condition the supply.

I donā€™t think soā€¦

Sorry - Iā€™m not sure - itā€™s been a long time since I really played around with it, and I run the system permanently anyway. I do have some averaging in the software to filter out any more noise, and I do notice that when Iā€™m filling the tank from another tank, it often reads a bit higher (the water from the other tanks just comes in from the top, and I guess disrupts the pressure as itā€™s pouring into the tank). I donā€™t notice this when itā€™s raining and the input flow is therefore quite lowā€¦

Interesting, must be the kinetic energy translating into higher pressure. I hope the increase is not more than 5cm in readings. Otherwise, need to do intelligent compensation in OH, if OH already knows that refilling pump is ON.

@chris Hi i was working on the same project but i have some issues with pressure leakage with respect to time. can you elaborate the type of tubes , connections, if possible some closeup pictures of the connections. Thanks

I canā€™t really provide too much more than the photos above Iā€™m afraid as itā€™s all quite enclosed. I use thin flexible plastic tube - Iā€™m not sure exactly the size, but itā€™s a tight fit over the barb inlets on the sensor. You can see the tube in the photo above although as everything is black, itā€™s a bit hard to see well. I guess itā€™s about 1/4 inch outside, and 3 or 4 mm inside diameter to fit over the sensor inlet.

This doesnā€™t really leak - maybe after a year or so it might read slightly lower than I think it should, so I pull the pipe out of the water, and that resets everything, but itā€™s pretty good otherwise. Iā€™ve certainly not done anything special to get it to seal.

Thanks @chris. The tube is 3 or 4mm, so how come it doesnt get blocked by dust or any other particles inside the tank? or you faced any issues?

Well, it never has been blocked :wink: . The tube fits over the sensor, so this is how the sensor is designed. If you are really using a viscous fluid, then maybe this will be a problem, but if itā€™s reasonably clean water, then it shouldnā€™t be a problem. In my case, the water is not especially clean - itā€™s an irrigation system collecting rainwater from the roof of some buildings and it does get some muck in the tank. Itā€™s never caused any problems though.

Arun, you have to design the connection in such a way that there is a mesh in between and cleaning is easy. And to avoid pressure leak, use hard tubes like the ones in RO water purifiers.

Thanks. Bare with me but i dont get the mesh point. Here is my connections, 1st pin Vout , which i monitor using a multi-meter, 2nd and 3rd ground and vcc respectively. The voltage in multi-meter increases as the water increases, But after some time the readings in the meter seems to decrease even for same level of water. As for as the tube im using the flexi tube as @chris mentioned. May be i have to look for a little less diameter flexi tubes.

I meant water connections. You need to design them for convenience. The mesh catches all dirt and you should be able to clean it easily. Look at how solenoid water vales are designed. They got bolts to open and clean the diaphragm membrane.

Yes, good point - when I said mine was ā€œflexibleā€ - itā€™s hard, but it bends and obviously pushes over the barb. Itā€™s not a soft rubber/plastic compound.

Thanks @chris and @diyha , will change the tubes and see how it goes

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How come plastic/rubber soft tubes loses pressure?
Does the vapour reaches out of the tube? @diyha @chris

well it expands! It absorbs pressure like shock-ups in your car.

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Thanks again @diyha :slight_smile:

Can i get a recommendation on what tubing to use with the MPX5010DP sensor?

This tubing has an internal diameter of 3mm but is flexible so is not good reading the comments above. Since my application is for drinkable water supply I need a tube which is food grade safe. I can only find RO tubing of size of 0.25 inch or 0.375 inch on Amazon.com, the data sheet suggests that the nozzle is 0.130 inch in diameter.

Checked with RO tubes. No leakage now :smile:

@trumee https://www.amazon.com/Plastic-Tubing-Filter-Aquariums-Refrigerators/dp/B06ZZS9VZW

check the link it has a inner dia of 1/8 inches. thats not what im using tho. I just picked up from my RO filter.

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@chris, I have a situation where I want to measure water and the tank is not gravity fed. It is below ground level. anything for this situation you would suggest.
Well I assume many here might be putting the pipe from top the tank itself till it reaches bottom.

image

Another point I am trying to see is if I can run this on a battery. I just want measurements probably 2-3 times a day.
I dont want to make it ultra efficient by using BLE and stuffs. I wont be having a host. I only have a WIFI access to the point where this equipment can connect and relay the data.

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The same system should still work fine. Iā€™m not sure what you mean by ā€œGravity fedā€ - is there a pump or something? Either way, the pressure sensor will still work fine - itā€™s just measuring the pressure of the water at the bottom of a tank.

Hi all,
we are using a low cost open solution with Arduino sensor JSN-SR04T for several years. Water tank level is recalculated for volume in liters. We would like to share our solution with community. Detailed tutorial how to set it for OpenHAB3 together with Arduino script you can find on link below:
https://opentux.eu/blog/measuring-water-tank-level-in-reservoir

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