Round water tank level sensor

[zboblamont]

@Denverado If this is a JSN-SR04T-2.0, as @Boots33 has already alluded to, now is a good time to take up religion. Spent a further 5 hours this afternoon trying all manner of variations of pullup resistor and sketch configurations per only available info and came up nada... Good luck... It is a veritable Chinese puzzle....

[Denverado]

@zboblamont I don't have a problem with my sensor. It works perfectly. It just casts a really wide beam. I'm estimating around 60 degrees!!! Has anyone tried changing the variable inductor on the unit to see if the beam can be narrowed?? Or does anyone have a schematic of the unit, as I have a friend who is an electrical engineer and might be able to help?

[Denverado]

@zboblamont I got mine to work by following the instructions from this guy. I also found the following drawing. . So my therory is if you change the variable inductor. You should be able to narrow the beam..... just a therory. If someone wants to try it... im happy to hear the results.

[Denverado]

@Boots33 Sorry mate I have kind of taken over your thread! The project looks great. I might have to try the same sensor as you.

[Boots33]

@Denverado Not to worry, I like the use of the voltage divider in the article you linked to. Always room for more ideas.

[zboblamont]

@Denverado For clarity, you mentioned previously your sensor was the JSN-SR04T, I was referring to it's modern incarnation the JSN-SR04T-2.0. Although advertised as the former, it was the latter which was delivered. Another guy found no problem with the original either, until he got the 2.0, which seems to be a bit of an enigma.

[Denverado]

@zboblamont I have the 2.0 as well.

[zboblamont]

@Denverado The puzzle continues then... I could not get it to work at all even having read through your linked post and meticulously following every step. All very strange...

[zboblamont]

@Denverado I would intrigued if the electrical configuration of a transducer could influence it's formation of an ultrasonic cone as I understood this to be down to the emitting diaphragm thereby physical), but my only experience of ultrasonics was in the water industry where we would confine the transducer in a pipe to negate offside reflections to measure distance to a surface. The objective was to hit still fluid which was the shortest echo path back to the receiver. The shortest route was the trigger....

[Huw Thomas]

I've been searching online for a project like this and it looks great. I'm doing something similar with an oil tank and have everything up and running, but the sketch I'm using is really basic, it just returns distance to oil level. Is it possible to change your sketch to allow for a rectangular tank, rather than cylindrical?! I'm an absolute beginner when it comes to coding unfortunately so any advice would be great. Thanks.

[zboblamont]

@Huw-Thomas Not so much a coding issue Huw, it's basic mathematics once you have the depth to surface and the cross section is a constant over the range.
You will know or be able to measure the height from the sensor head to the outlet and the full mark. Everything between is a proportion of height multiplied by floor area whether it is capacity or spare capacity...

[gohan]

@Huw-Thomas it's basic geometry 😀

[Huw Thomas]

Yes I realise that , I just wasn't sure at first where I needed to change things in the sketch. I think I've worked it out. I have zero experience in reading programming code so couldn't at first find the PiR^2h equation to change it, but now I've found it.

[Boots33]

@Huw-Thomas Sounds like you are heading in the right direction.
The water percent available calculation should work unaltered for a rectangular tank and you have already found

waterAvail = PI* pow(tankRad,2)*(((fullHeight-outletHeight)+sensHeight)-pingHeight)/1000;    // calculate water available in litres

That is the line that will need the change with the suggestions from above.

[Lawrence Helm]

@Boots33 Have you thought about sending the days available. i.e. calculate daily usage and divide that by the water that is still available? would have to roll the numbers i.e. say take the last two weeks of how much the water dropped in a day averaged out... if that makes sense. :)

[Boots33]

@lawrence-helm The tank that I am monitoring is used primarily for garden watering and topping up the pool, so it does not really have a regular sort of use. We also live in an area of frequent rainfall so the tank can stay at 100% for weeks on end.

I can see that your idea would be a good addition to the sketch if the tank was to be used for general house duties where more frequent use would likely give a more meaningful result.

[Ritesh T]

Sorry for bumping up an old question but I’m in the same boat of requirement.

And to my surprise there are quite a few new sensors in town:

This one has 2 transducers instead of 1 therefore has less minimum detection distance as compared to JSN SR04T. It is also completely sealed and waterproof.

Ebay spam link removed by moderator

Before finalizing on this I had bought another one which was a waterproof modified version of HC-SR04 from here

Ebay spam link removed by moderator

The 1st one is much more rugged and waterproof as compared to the latter one.

[Boots33]

@ritesh-t If you have not already found it you may also benefit from the thread by @zboblamont which can be found here. It addresses some issues of unstable readings that were occurring when the water in the tank was at a lower level.

[zboblamont]

@boots33 To be fair that was specific to the SR04-2.0, the technology has moved on a bit since non-waterproof twin head devices were the standard, but I confess having discovered the error it verifies with the Class-D quality water meter on the house-side. I may have to recalibrate the Litres/mm but the tank shape is not uniform cross section.
@Ritesh-T All you can do is try the version you bought, but the original suffered badly inside a sealed tank where moisture was very high indeed, and housing it to protect the board may prove tricky. That was my reasoning for going with the parking sensor button type with remote board, plus the sensor is a snug fit in the end of 3/4" pipe/socket. The only recurring problem is condensation below -10c, perhaps your environment is different or have better luck with yours.

[CrankyCoder]

I made a sensor like this myself. i took a non-water proof one and drilled holes to match the sensor in some plexiglass. and sealed around it with silicone. This worked until florida tried to drowned me out and flooded my entire sensor housing lol