the container is plastic, or styrene, I am not certain the EXACT liquid in it at this time

 

How about a light beam from one side to the other that is blocked when the container is full?

I must have missed where you told us that it was filled with a liquid.

 

I must have missed where you told us that it was filled with a liquid.

Ohhhhhhhh, probably forgot to mention this, sorry

 

How about a light beam from one side to the other that is blocked when the container is full?

Thank you for your input. Please see the new Specs for the project

 

I must have missed where you told us that it was filled with a liquid.

Thank you for your input. Please see the new Specs for the project

 

I must have missed where you told us that it was filled with a liquid.

Can a infared emitter/receiver be used, even if the container is using water, which is clearer than most, but not usually optically clear??

 

Can a infared emitter/receiver be used, even if the container is using water, which is clearer than most, but not usually optically clear??

According to Google water is opaque to most IR wavelengths.

 

DARN!!

 

DARN!!

Why so? That would seem to make it easier to detect the presence verses absence of water.

 

Reflective sensor with the liquid surface acting as the reflector?

Fix an emitter at a given angle on one side then set detectors on the other side to sense reflected light at different levels?

 

Why so? That would seem to make it easier to detect the presence verses absence of water.

Agree.
An IR beam passing through the container near the top would indicate "when the unit is approximately full and approximately not full".

 

When you make a post please do not change the post except for minor typo errors. Doing so makes replies to the original post a bit incoherent.

 

Agree.
An IR beam passing through the container near the top would indicate "when the unit is approximately full and approximately not full".

If this is the case, this may be the only way to go

 

When you make a post please do not change the post except for minor typo errors. Doing so makes replies to the original post a bit incoherent.

Thank you, I shall

 

If this is the case, this may be the only way to go

Not necessarily.
In this circuit the canister has a conductive pad near the top and another pad somewhere below.
It's not about capacitance but resistance.
When the fluid level reaches the top pad voltage will be applied to reset pin4 of the 555 and the LED will begin to flash.

 

....the liquid inside may be many different materials of varying opacity, including water

Without some constraints on what the contents might be, it is difficult to suggest a general solution.

Is it usually water or a solution of water? In that case a conductive or capacitive sensor should work.

OR might it also sometimes be hydrocarbons eg solvents and be non-conducting and non-ionic.

Perhaps a reflective sensor? Or transmissive across the container? Or a float switch?

It depends on the nature of the contents.

 

Ok, I have realised that I have set my specs waaay to high for this project.
I have simplified it significantly, as I put my typing in gear before my Brain.
I thank everyone for considering this project, and helping in any way possible.
Please consider my new specs, and ignore the original

NEW SPECS:
The cannister is 6 cm high (missing in the attached drawing)
I have a plastic container,(see attached sketch). The only thing missing is its height, which is 6 cm., with a void between the inside and outside of the container (see Illustration).
Is there a way to use capacitance or infared beams to decide when the unit is approximately full and approximately not full. (no measuring anything else)?.
Accuracy and or speed is not important at all, but take into consideration that the liquid inside may be many different materials of varying opacity, including water, which is not 100% optically pure usually.

Someone has suggested the following schematic...will it work?
View attachment 358749

____________________________________________________________________________________________________________________________________________________

Is there a circuit that will TURN ON when the container is full, AND OFF when the container is empty.
I cannot use contacts within the container (which would otherwise make this project easy).
So I would like try to do this by measuring capacitance. I can probably fit a 9v battery into it, or a smaller Lipo battery.
Im looking for a design that doesnt use a microcontroller (ya ya ya...I know)
I know that there are industrial capacitance sensors that could do this, but I dont have a lot of space in the interior.
Thank you in advance for any advice.

I have added a bit more explanation, after thinking about this more.
This can simply be, flask is full, flask is empty, rather than taking into consideration of percentage full and empty

Hello there,

From what you are saying, it sounds like an ultrasonic detection would be best but you still have to do some testing with the various liquids.

The beam would come from above, and the level would be determined from the time it takes the reflection from the top surface to return.

An alternate method would be a laser interruption beam. This might be tricky with a cylindrical container though better would be a flat sided container. The beam should be refracted when there is water in the container, which would mean it would not hit the sensor directly, or it would be blocked a lot if the liquid was not clear.

 

Hello there,

From what you are saying, it sounds like an ultrasonic detection would be best but you still have to do some testing with the various liquids.

The beam would come from above, and the level would be determined from the time it takes the reflection from the top surface to return.

An alternate method would be a laser interruption beam. This might be tricky with a cylindrical container though better would be a flat sided container. The beam should be refracted when there is water in the container, which would mean it would not hit the sensor directly, or it would be blocked a lot if the liquid was not clear.

Thank you very much, this would be, but I may not have room for the sensors

 

Without some constraints on what the contents might be, it is difficult to suggest a general solution.

Is it usually water or a solution of water? In that case a conductive or capacitive sensor should work.

OR might it also sometimes be hydrocarbons eg solvents and be non-conducting and non-ionic.

Perhaps a reflective sensor? Or transmissive across the container? Or a float switch?

It depends on the nature of the contents.

I cannot use a float switch, but to answer your question it will be various Potable liquids

 

I did find the following schematic. I like it because its less likely to be effected by outside sources. Whatcha think??