Hello!
I was wondering if anybody could recommend a water level sensor like the link below but one that is longer? I would like 3 inches long if possible.
Any recommendation would be great thanks!!
Maggie
Hello!
I was wondering if anybody could recommend a water level sensor like the link below but one that is longer? I would like 3 inches long if possible.
Any recommendation would be great thanks!!
Maggie
msbarbe2:
Hello!I was wondering if anybody could recommend a water level sensor like the link below but one that is longer? I would like 3 inches long if possible.
Any recommendation would be great thanks!!
Maggie
How do you know the one you linked to is not long enough?
What do you want to use it for? I hope not for continuously monitoring water level. The humidity will kill the electronics in a short time.
Paul
ever heard of ultrasonic sensor, you can employ it as level sensor for your project
@Paul. I have a container in mind and it is deeper than 1.5 inches. so I would like one that could measure more depth. I just want it to help with filling the container with water. I was thinking right after it reached the level I wanted I could stop the water flow and the power to the water level sensor. Would the humidity affect the electronics even if it was off?
The user might want to vary the amount of water in the container hence a longer water level sensor.
@Kassimsamji I believe the ultrasonic sensor would be disrupted if there are other things in the container? There will also be a basket in the container so I think that might cause it to have a false reading.
I was considering doing a more simple design such as this.
https://www.electroschematics.com/9964/arduino-water-level-indicator-controller/. but i dont know about safely running current through water.
The current here I believe is 0.22mA so should be fine??
Would like a more accurate method though. Any ideas?
Do you remember chemistry and what water/acid does to copper? Even freshly distilled water will absorb carbon dioxide from the air and become acidic and react with the copper. The oxygen in the air will react with copper in the presence of moisture. Being powered or not makes no difference. Notice how the sensor operates. The resistance between the copper strips on the circuit board is reduced by the covering water. So the strips are continuously in water. Also the circuit board material, fiberglass, will absorb some water.
So, that sensor is great for occasional submersion in water, but not for long. The same applies to the other sensor you proposed. It also has copper submersed in water. I bought two of those type devices for my irrigation water storage tank. Then I recalled at least two of the wires would be in water 100% of the time. Went with float switches.
The float switches are 100% water proof and the connecting wires are in PVC pipe. The switches tell the Arduino about the lower level of water znd when the tank is full. Would such a scheme work for you?
Paul
I was thinking that the copper wiring was lined with tin to prevent corrosion? But you are probably right. I doubt that is good enough for submersion applications.
I was looking at the float sensors but they looked large. I have less than an inch gap. But ill look into miniature float sensors.
Thanks for all your help! I'm still a newbie so I appreciate the help
Maggie
You could weigh the vessel and water
I would go with your Arduino water level sensor, but use platinum wire so the water will not affect the sensor and will not contaminate the water. Use copper wires to connect to the platinum wires so the copper stays out of the water.
Paul
The board you linked is not a water level sensor. It is a raindrop or flood sensor, not intended to be continuously immersed in water (which, as pointed out above, will destroy it rather quickly).
If you want a level sensor designed for continuous immersion, this will work. Similar sensors in various sizes are available.
Or make one yourself (as did Scott Edwards in Nuts & Volts) from plastic tubing and aluminum foil, instructions here (pdf).
Thanks the Adafruit Tap looks perfect! Ill try that out for my application. Thanks!
That's indeed a water sensor, not water level sensor.
Add a grain of salt to your water and the readings will be wildly off as the conductivity of the water changed.
Then there's also the corrosion issue...
I have found that you can create a water sensor by sandwiching two wires in a plastic (see attached picture). I did this with tape, but if you laminated the wires in plastic this would be a lot more durable. The capacitance will then vary depending on how far the sensor is immersed in the water (or other liquid). I have been told that this is how they measure fuel levels in aircraft (but don't sandwich the wires in plastic!).
The capacitance will typically vary from a few picofarads to tens of picofarads and can be measured with the capacitance library (or just search for "capacitor" in the Arduino IDE library manager).
This should be good for measurements of a few millimetres up to several metres I would have thought.
Just try to keep the leads that connect to the Arduino as short as possible...
Two strips of aluminium foil works better than wires.
Adding an active shield works even better (but this becomes technically quite complicated, as the potential of the shield has to accurately follow the potential on one of the two strips, without affecting it).
A float sensor is nice and simple, but does sometimes have space issues... and isn't always terribly accurate and repeatable. A ranging sensor (like light time-of-flight or ultrasonic) can work vey well, but it's useful to have a small "stilling well" to bounce the beam down. These can get you down to millimeter resolution if you have a need. Two wires into the water as a "high/low" level sensor is good, repeatable, and take next to no space, and normally the transition from wet to dry states is nice and easy to detect, and only requires a single pin and the Arduino's ADC.
Another possible solution is a pressure sensor. For shallow water levels, I use a BMP280 or similar, sealed in a controlled volume that I can then port to a plastic tube - put the open end of the tube at the bottom of the container, and as water level goes up, the pressure goes up, while your sensor stays completely out of the water (it would be great if these sensor come ported, but most ported pressure sensors end up being more costly... barometric sensors are cheap, and have high resolution). That works great if you don't mind talking to an I2C sensor and spending a few bucks, AND if the water is shallow - but it's easy to go "too deep" with a barometric sensor and hit the upper sensing limit. If you want absolute water level (maybe not a factor for you) you might need to compensate for air pressure (it's usually a small correction for water depth).
Honestly the cheapest and easiest would be "ground wire exposed at bottom of tank, sensor wire at level of interest, watch for non-zero resistance", but there's a lot of options. Measuring the change in capacitance of a twisted wire pair with varying water levels is almost as simple with a simple RC circuit and can get you a continuous measure of the depth without the issue of exposed metal to water (want to watch resistance change? Run even a trickle current between two exposed wires under water - keeping those systems calibrated is a pain, which is why you start looking at all sorts of exotic, rare, hard-to-source or expensive materials).
Currently I'm using a pair of barometric pressure sensors (BMP/E280's) with a physical negative biasing (think Torricelli's barometer with the pressure sensor at the top) to get centimeter resolution of stream level, and similar pressure-sensor-based approaches have been useful for measuring wave height and action in marine environments.
I have been told that this is how they measure fuel levels in aircraft (but don't sandwich the wires in plastic!).
That article has a lot of generalizations in it with respect to small aircraft. I own a 4-seat high wing airplane and can say for a fact:
msbarbe2:
@Paul. I have a container in mind and it is deeper than 1.5 inches. so I would like one that could measure more depth. I just want it to help with filling the container with water. I was thinking right after it reached the level I wanted I could stop the water flow and the power to the water level sensor.
I have a quite similar situation in my project and my water sensor consists of a +5V wire in combination with second wire connected to an Analog In pin. If the analog pin reads a value greater than 0, then its wire is covered with water - quite simple isn't it?
You can have two or more wires for measuring different water levels in your container, e.g. low, medium, high.
It's primitive but it worked reliable for years.
That will work, especially if most of the time both wires are not exposed to water.
Have you tried ultrasonic ranging sensor? I've just finished the library for HC-SR04, HC-SRF05, DYP-ME007, BLJ-ME007Y sensors. Cost $1.
Features:
Those sensors are not water proof.
msbarbe2:
I was thinking that the copper wiring was lined with tin to prevent corrosion?
...
Hi Maggie, tin is easily oxidized in acid solutions.