Basically 3 tanks 2K to 5K litre capacity, non-metallic, heights 6 to 8 feet. Having got a quantitative reading from all 3 tanks, there's logic that also controls a pump to keep the levels at a required level.
Unfortunately, yes, I did look at the alternatives you mention and had to discard them for various reasons:
Floats (I assume you mean the kind that is anchored, and has a float connected to a pot): would be difficult to get movement thruought the height of the tank. Also, the ambient humidity would junk it in a short time.
Hall effect or optical would be good, but I need to sense 10 levels in each tank; would be complex/expensive. I even considered an IR scheme with the technique Bruce describes on his site for distance measurement. Not to mention optical encoders with a float.
Yes, power is available, but I think if i could get away with data-over-the-Vcc-line, that would be more elegant. And cheaper than RF.
But first, I'm going to try out Melanie's suggestion about PWM and ADC;
Thanks; I've been trying to achieve this for a long time. If there's any interest on this subject, I'll keep posting my observations on this thread.
I do not know how I missed this post .. . Here is an optical method. Water is a pretty good difuser of light, way better than air, if you make up a vertical pipe with clear lucite pins penetrating the pipe and covered on the pipes inside with black tubing so light will not penetrate from their sides, when they are covered with water the light should be able to enter through the ends, or just use fiber optics. Please, pay no heed to the fact I misspelled TUBES as Tubs in the picture.
Last edited by Archangel; - 21st July 2009 at 09:22.
If you do not believe in MAGIC, Consider how currency has value simply by printing it, and is then traded for real assets. .
Gold is the money of kings, silver is the money of gentlemen, barter is the money of peasants - but debt is the money of slaves .
There simply is no "Happy Spam" If you do it you will disappear from this forum.
Hey Joe,
That is a good idea, I am going to give it a try.
For years I have had a similar problem but with hot sulfuric acid under pressure. Sonar and radar sensors work for a time, but sooner or later everything fails in that environment.
I never thought to use fiber optics.
Thanks!!!
Dave
Always wear safety glasses while programming.
.. . Here is an optical method. Water is a pretty good difuser of light, way better than air, if you make up a vertical pipe with clear lucite pins penetrating the pipe and covered on the pipes inside with black tubing so light will not penetrate from their sides, when they are covered with water the light should be able to enter through the ends, or just use fiber optics.
Looks good. In fact, I guess one could use IR detectors directly in place of the lucite pins, of course covered with black tubing so that only a small aperture at the tip is open.
Detecting water level with optical system has one big enemy : The algas growth!
Al.
Hi Al,
I was pretty sure You would mention that one, and prepared for it
Illuminate the tube only while checking level. A 2000 liter tank level is not likely to change very much in an hour, so check intervals do not need to occur too often, still EVENTUALLY algae is likely to occur. Perhaps make the sensor rods screw in for cleaning. Dave's UV light would work, but is expensive.
If you do not believe in MAGIC, Consider how currency has value simply by printing it, and is then traded for real assets. .
Gold is the money of kings, silver is the money of gentlemen, barter is the money of peasants - but debt is the money of slaves .
There simply is no "Happy Spam" If you do it you will disappear from this forum.
Hi Joe and Dave, going this way it could happen that this thread will come up with the best water level sensor ever invented.
Al.
Yep, kind of makes your signature line hold true.
I was googlin around earlier for fiber optics and saw a site advertising "side glow" fiber. It appeared to light up like a neon tube.
My thought. It it would receive light into the edge ? If so then maybe the more of less exposed would change the intinsity of light at the end? Make it work backwards.
I missed this post
Originally Posted by ardhuru
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