Hello, I have a Liquid level sensor (RB-02S048) that I am planning on using to detect the water level in a closed vessel that will be dispensing water. I still have not designed the vessel because I am not sure how much of the sensor can be submerged or how to cover the area that can not be submerged. I have searched for examples but haven't found anything similar. Could someone please help with this dilemma? Thank you in advance
OK, please understand - this is a toy. Nothing more.
What is your "closed vessel that will be dispensing water"? Just what do you want to know about the level? When it is full? 50%? 25%? 5%? Which one or two of these?
Here is a level sensor which you bolt into the side of the container at a particular level which allows you to detect whether the water is covering that level. It - unlike the float valves - has no moving parts which means it cannot release particles as it "wears".
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Weighing the container would be a good way to tell how much water is inside. And the scales or load cell will not need any contact with the liquid.
...R
Hi,
I have used some industrial versions of the optcal sensor in post #1 and they are very good.
Especially with fluids that are conductive and need a non contact sensor.
Tom.. 
you can buy float switches and have 3 or 4 to tell you when you pass thresholds.
you can mount them on a PVC pipe, all internal wiring and insert it from the top.
for larger vessels, an ultrasonic sensor can tell you when the level is a meter away, up to about 1/3 of a meter when the sensor cannot see any closer.
please state more about your needs.
using a tank that fills when it gets empty and fills to some high point is simple with float switches
knowing a deep tank is 41% full is easy with ultrasonic.
what I do not like about drilling holes in the side of the tank for a sensor is, drilling holes in the side of the tank.
I have 2 rain barrels and use ultra sonic in one and a float in the other. since I only care of they are empty, it is just for fun.
for my rain barrels, if they are empty, I have to water from the well. so, it is just a question of what is needed at what time.
Paul__B:
OK, please understand - this is a toy. Nothing more.What is your "closed vessel that will be dispensing water"? Just what do you want to know about the level? When it is full? 50%? 25%? 5%? Which one or two of these?
Here is a level sensor which you bolt into the side of the container at a particular level which allows you to detect whether the water is covering that level. It - unlike the float valves - has no moving parts which means it cannot release particles as it "wears".
[
The vessel is for dispensing water to an obstacle avoiding robot that will also clean floors. The robot will be programmed to stop once the water reaches a desired water level. I really don't have many options for buying another sensor due to location and time. I need to work with what i have right now
Take a piece of plastic pipe (at least 3 diameters long) and make metal ends for it, perhaps out of coins. You will solder wires to the ends then seal those after filling the bottom 1/4 of the tube with regular tap water.
Now you have a float that will float on its side and the end wires will conduct through the water inside.
You use the 2 wires to tie the float to the bottom of the vessel so when the water is low it floats flat but when the water is higher it floats upright or at an angle where the water inside doesn't touch the top metal.
There will be times when the float might be close to flat and bob a bit, they will need debouncing.
ineed_alot_ofhelp:
The vessel is for dispensing water to an obstacle avoiding robot that will also clean floors. The robot will be programmed to stop once the water reaches a desired water level. I really don't have many options for buying another sensor due to location and time. I need to work with what i have right now
the red sensor will wear out in months of use. the sensor self destructs.
if you must use it, then do know that it will fail over time.
get your project to work with what you have. and if it is just for a class project, you should be fine. if it is for use over a long time, then get one of the other styles and be ready for when it fails.
ineed_alot_ofhelp:
If you check the level every millisecond or so it won't last near as long as if you check every 10 seconds (10000 times less often) and no power in between.
For a short time you could strip the ends on 2 wires, one wire bare end goes to the tank at the threshold and the other goes to the lower water limit depth. Over time the bare ends will corrode and that is the "short time". Solder a stainless steel screw to the bare end (seal the wire end) and it will take a lot longer to corrode. When the short time gets near, cleaning the contacts extends the life of the DIY sensor.
Did you all read the OP has a "CLOSED" vessel. That means no air vent. He as to fill it by compressing the air in the vessel. I submit a pressure sensor can be calibrated to indicate how much liquid is in the vessel.
Paul
Paul_KD7HB:
Did you all read the OP has a "CLOSED" vessel. That means no air vent. He as to fill it by compressing the air in the vessel.
But, closed doesn't necessarily mean pressurized. It could gravity fed, like this:
dougp:
But, closed doesn't necessarily mean pressurized. It could gravity fed, like this:
Right! Then he could measure the vacuum!
Paul
Paul_KD7HB:
Did you all read the OP has a "CLOSED" vessel. That means no air vent. He as to fill it by compressing the air in the vessel. I submit a pressure sensor can be calibrated to indicate how much liquid is in the vessel.Paul
True. And those coefficients of expansion are only true at standard pressure.
But --- I don't think any of that matters when the OP only wants to know when the tank is getting low.