Water Level Measurement Sensor

[mlucas]

Hi YoYo,

What was your final solution for this project? I'm in the process of trying to solve the problem as well.

Thanks,
Michael

[YoYo]

Hey Michael,
It was awhile ago, but here's what I remember about the story:

I did try the Max Sonar item. To get it to work accurately with water, I had to add some foam insulation to float on the water so the sensor would read accurately. It was very picky about where it was aimed. After a few weeks, it started acting intermittently though. After messing around with a bunch variables, I finally determined it probably wasn't up to the humidity in there and set it aside.

What I finally ended up with, and what has worked flawlessly since it was put in around 3 years ago, is a used ultrasonic Flowline sensor I obtained via ebay. It did not require the foam, (shoots right at the water), seems to be very consistent and accurate, and just works. I don't remember what I paid, but I think it was around $200. It was a <meta http-equiv="Content-Type" content="text/html; charset=utf-8"><meta name="ProgId" content="Word.Document"><meta name="Generator" content="Microsoft Word 11"><meta name="Originator" content="Microsoft Word 11"><link rel="File-List" href="file:///C:%5CDOCUME%7E1%5CBrianM%5CLOCALS%7E1%5CTemp%5Cmsohtml1%5C01 %5Cclip_filelist.xml"><!--[if gte mso 9]><xml> <w:WordDocument> <w:View>Normal</w:View> <w:Zoom>0</w:Zoom> <w:PunctuationKerning/> <w:ValidateAgainstSchemas/> <w:SaveIfXMLInvalid>false</w:SaveIfXMLInvalid> <w:IgnoreMixedContent>false</w:IgnoreMixedContent> <w:AlwaysShowPlaceholderText>false</w:AlwaysShowPlaceholderText> <w:Compatibility> <w:BreakWrappedTables/> <w:SnapToGridInCell/> <w:WrapTextWithPunct/> <w:UseAsianBreakRules/> <wontGrowAutofit/> </w:Compatibility> <w:BrowserLevel>MicrosoftInternetExplorer4</w:BrowserLevel> </w:WordDocument> </xml><![endif]--><!--[if gte mso 9]><xml> <w:LatentStyles DefLockedState="false" LatentStyleCount="156"> </w:LatentStyles> </xml><![endif]--><style> <!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0in; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";} @page Section1 {size:8.5in 11.0in; margin:1.0in 1.25in 1.0in 1.25in; mso-header-margin:.5in; mso-footer-margin:.5in; mso-paper-source:0;} div.Section1 {page:Section1;} --> </style><!--[if gte mso 10]> <style> /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} </style> <![endif]-->Flowline Echotouch LU20-5001.

It interfaces via current loop to an input on my Secu-16 which I have configured for current loop. It also requires a 24v supply as well.

Since then, I bought another unit (on ebay), not the same model, but for a lot less to monitor something else. They work great and never need attention. It's a shame the prices are so high for them, but you can always save a flowline search on ebay and wait for one to go cheap...

[mlucas]

Thanks YoYo. I thought this might be a little easier that it is!

[YoYo]

I see MaxBotix has since released some very narrow beam sensors with an IP67 rating (outside, water resistant), that might now work well for this at about $105.

I guess the advantage of going with one of the MaxBotix sensors is you have more interfacing options, serial, voltage level, PWM, etc. I think I used the serial interface along with a simple script with good results.

I also see over at the cocoon forums that someone has programmed a PIC to service a series of them, but only requiring one serial connection to your PC. That seems like a great idea to me... There are a number of threads pertaining to the device there.

I guess the main hangup with the flowline sensors is that you need some sort of current loop interface to your home automation PC, but I think any analog input can be converted to current loop via the attached info.

[Michael McSharry]

If you are interested in the Maxbotix sensor then an easy way to interface into Homeseer is at http://board.homeseer.com/showthread.php?t=136825. With this approach the measurements are modulated with the discrete control lines of the serial port so measurements are only taken at specific intervals rather than having the data continually streaming into the computer.

[dustball62]

I just was reading this thread as I have the same problem with the cistern. I just had an idea if a depth sounder would work-like those on a bass boat.
float it and with the correct depth you could calculate the gallons based upon the circumference.

[mark_anderson_us]

All this talk of water has got me to thinking about something I've wanted to do for awhile....

And that is measure the actual level of water in a small cistern outside my home. Right now, I have a float switch that tells me when the level reaches a certain point, but I'd really like to know how many feet of water are in it at any given time.

I've looked at a few non-contact options, like the Sonix-40, and a few others, but they're all over $650, which seems a bit expensive to me.

Anyone got a lead on something perhaps lower tech that would do the job?

Hi yoYo

Did you ever build anything?

Regards

mark

[YoYo]

Hi Mark,
If you scroll through the rest of the thread, you'll see I ended up getting a used Flowline sensor that has worked without trouble for the last 4 or 5 years.

[mark_anderson_us]

Thanks Yoyo

Would you mind sharing how you connected it. Seems the sensor would work, but no idea how to connect to HomeSeer

TIA

Mark

[YoYo]

Hi Mark,

Do you currently have any interfaces that do current loop or analog voltage inputs?

The flowline connects via 4-20ma current loop. the idea is that the current varies from 4 to 20ma depending on the reading.

To make this work with HomeSeer, you need either an interface designed to accept current loop devices, or an analog input interface with the circuit mentioned above to convert it to current loop. You then do some tests to come up with a formula to convert the reading to an actual measurement. The formula will be a linear equation in the form of y = mx + b. I took some readings, then used the linear regression function in Excel to come up with a formula I use in a HS script.

It didn't exist at the time, but Maxbotix now has a series of sensors they claim should work well for this application. The nice thing about the Maxbotix is you have some choices for what interface you'd like to use. Take a look at the message a few up to find a link. Also, if you wanted to use more than one, I understand their is a PIC programmed to allow you to hang several off a single serial port, and you can get the readings directly without having to use a formula of some kind.

[hasanicon]

Hello Michael, We are using a couple of levels sensor and they delivering good service for a long time. iconprocon.com providing the complete line of level measurement. Even you can try this. They are eager to help you.