I am looking for ideas for a water depth sensor. I saw one once that used a ping-pong ball but can’t find it again and I would like to take another look if anyone knows where it is located. I would like to include water temp as well.
How deep? How clean? Flowing or static? How accurate should the result be?
Hmmm, well its for my pond. I need to know when to add water from the irrigation pipe. I just want to know when it gets low so wouldn’t need much room for measure…maybe a foot or so from max to min. Static. Water is muddy most of the time.
If you don’t want to use a mechanical float valve then the next level of complexity would be a float switch http://www.aquahub.com/store/index.html and a relay to drive an electric valve.
I’m with Niko. Use a float switch. A foot of water is a fairly narrow range to measure accurately and inexpensively. FWIW, 1 PSI = 2.8’ of water, about 33.6". A foot of water is about a third of a PSI.
Done right, a float switch and solenoid valve would automatically refill the pond with no input from you. I forget the NC/NO standard for float switches, but you want one that’s ON when hanging down, and OFF when floated up. Wire it in series with the solenoid and power supply. You can get float switches from the site Niko mentioned, or any place that sells sump pumps. You probably don’t need a relay, unless you are running some high-power motor driven valve.
One with a cable can be adjusted for hysteresis, the distance between turn-on and turn-off.
If you add a second float that’s ON when it’s up, set it a little above shutoff of the other float, and connect it to a light, you’d have a high level alarm as well.
For reference a regular sprinkler valve is 300 mA at 24 volts AC. Failsafe is a good idea, wire two in series putting the second one above the lower one, then if the lower one fails the second will open the circuit when the water gets higher and hopefully before a flood.
I would think a toilet fill valve would be able to be rigged up to work. When the level dropped the valve would open to fill the pond… no electric would be needed.
I was going to make the same suggestion. Our swimming pool uses a similar auto filler. When you take off the outer housing, its the same type of thing we have in the toilet tank. Basic float that opens a valve when it drops and closes it when it reaches the set height.
One possible issue would be if you ever get a freeze. But I’m not sure if that is an issue where you are located. It isn’t a real issue here since it is covered and and in water that never gets that cold.
Noticed this morning that our pool was a nice balmy 42
FYI, I made a 1-wire IR sensor with a ping pong ball several years ago(http://www.howmuchsnow.com/waterlevel/).
Thanks, I had already read your site. I am going to wait for warmer wx before I tackle this project.
I also made an ultrasonic depth sensor using the PING sensor and a rabbit semiconductor processor (http://www.howmuchsnow.com/ping/).
I’m now working on a depth sensor that uses a laser line and inexpensive serial camera. I’m trying to hit the holy grail of 1/10th inch accuracy for snow fall reporting (snow depth only needs 1" accuracy)
nafis
You should resize your images on your page to fit the sizes you are attempting to use. Would load faster and reduce your bandwidth.
Is it possible to connect this to a Davis station?
There are users with ultrasound snow depth sensors connected to WD, if that’s what you are referring to.
Could that be used to mesure water depth as well?
Where could I buy such a sensor?
Here’s the thread http://discourse.weather-watch.com/t/13666
I don’t know how well that sensor would work at detecting a water surface, and WD only has the snow depth functionality.
I use a aquameta http://www.anadexlabs.com.au/
Niko initially wrote a little app for it to collect the data on windows. I now have it directly talking to Unix it might something for you.
H.