Hi All

I have a small tank.

I need to monitor the liquid level over time. Is anyone aware of sensors similar to?
Gravity: Photoelectric Water / Liquid Level Sensor For Arduino | The Pi Hut

That can output a voltage or signal proportional to the liquid level. I think this version is static.

I would like to avoid developing ultrasonic sensors if something economical is available. Any suggestions?

 

I have a small tank.

How small is the tank and how much can you spend on a sensor?
Maybe this?
Sensor

 

What about chemical-compatibility / corrosion ?

What must the Sensor withstand ?

An Automotive "MAP-Sensor" ( Manifold-Absolute-Pressure )
can accurately detect the Fluid-Level without any
requirement for submersion in the liquid,
and runs off of a 5-Volt Supply.
.
.
.

 

Hi All

I have a small tank.

I need to monitor the liquid level over time. Is anyone aware of sensors similar to?
Gravity: Photoelectric Water / Liquid Level Sensor For Arduino | The Pi Hut

That can output a voltage or signal proportional to the liquid level. I think this version is static.

I would like to avoid developing ultrasonic sensors if something economical is available. Any suggestions?

I believe this sensor only tells you that there is or is not water. It does not measure water level.

 

What about chemical-compatibility / corrosion ?

What must the Sensor withstand ?

An Automotive "MAP-Sensor" ( Manifold-Absolute-Pressure )
can accurately detect the Fluid-Level without any
requirement for submersion in the liquid,
and runs off of a 5-Volt Supply.
.
.
.

How would this work?

 

How would this work?

.
Liquid has weight that will create Air-Pressure in an attached Pipe / Tube / Hose which can be measured.
This method will remain accurate as long as the qualities of the Liquid remain constant.
No contact with the Liquid is required, only Air.
A standard household Washing-Machine uses this method,
all of them,
for as long as Automatic-Clothes-Washers have been produced.
.
.
.

 

Hi All

I have a small tank.

I need to monitor the liquid level over time. Is anyone aware of sensors similar to?
Gravity: Photoelectric Water / Liquid Level Sensor For Arduino | The Pi Hut

That can output a voltage or signal proportional to the liquid level. I think this version is static.

I would like to avoid developing ultrasonic sensors if something economical is available. Any suggestions?

What does "static" means?

 

What I mean by Static is that the sensor indicates if water is there or not, but not necessarily the level.

What I am trying to do is avoid creating a new design with the Time of Light Sensor if there is a demo or basic kit available.
Something like
Grove - Time of Flight Distance Sensor(VL53L0X)-(ToF) laser-ranging- Seeed Studio
But something encapsulated in some protection. case

 

What is the tank made of? What are its dimensions? What is the liquid?

 

What is the tank made of? What are its dimensions? What is the liquid?

It has a small water tank, maybe 80L max height 0.5 meters.

 

What I mean by Static is that the sensor indicates if water is there or not, but not necessarily the level.

What I am trying to do is avoid creating a new design with the Time of Light Sensor if there is a demo or basic kit available.
Something like
Grove - Time of Flight Distance Sensor(VL53L0X)-(ToF) laser-ranging- Seeed Studio
But something encapsulated in some protection. case

No. This sensor can show the level. You can see the wiki example code: https://wiki.dfrobot.com/Liquid_Level_Sensor-FS-IR02_SKU__SEN0205
You can also consider making an Arduino Liquid Level Meter with simple Homemade Sensor.

 

It has a small water tank, maybe 80L max height 0.5 meters.

.
If You expect the best solution to your problem,
ALL aspects of the project must at least be reasonably outlined,
and preferably described in detail, with pictures, and/or, drawings.

So far you're starving us for information,
~20 gallon water-tank ~18" tall
doesn't say much.

Is this another "Top-Secret" project ?
Will this become a commercial product for-sale to the public ?
Why do You need to know the level of the Water in the Tank ?
How much accuracy is required ?
How long will this setup be required to reliably operate without maintenance or repair ?
Is the Tank under pressure ?
What is the Tank made out of ?, Welded-Stainless-Steel ?, Polypropylene ?, Cardboard ?
Is the Water Hot ?
Does the Water contain any Chemicals ?
Must all holes in the Tank enter from the top ?,
or, can a hole be drilled in the side or bottom ?
Will the Tank be in a Hostile-Environment that is likely to be subjected to physical abuse or damage ?

C'mon, throw us a bone at least.
.
.
.

 

Measuring air pressure in a tube to the bottom of the tank is probably the most straightforward way of doing it. The pressure sensor can be mounted above the tank, connected to a small tube inside the tank, ending at the bottom.

Cheap, easy, well-deveoped technology used in washing machines.

 

Maybe you need this?
Operating Voltage: 9~36V DC
Output :4~20mA or 0~5V DC

 

One nice possibility is the water resistance. Just in megaohm scale the every purity water is conductor, thus etch the longer pcb line with multiple contacts, apply the code translator to economy the 1000 wires cable. But that is good for pure water not for, for example, acid solution.

Another way be used is capacitance what for water is about 81. Thus apply the U-shaped plastic channel where in both sides stay pcb rails and between them most of volume is filled by water under the test. Capacitance of such embodiment will changing sharply, proportionally to water level, not step-wise than previous construction. Sometimes the copper cladding are glued on top sides of square section insulator pipe, and then water is measured those being inside that pipe. Its mechanically simpler.

Most prost and simple way is to apply some appropriate are bubble material well floating in water, frigolit or vehicle fuel volume or toilet water box - all them have such things inside. As soon the thick wire in hinge allows to floating thing move up or down, then instead of that hinge may stand the potentiometer. So, the gasoline level measurer is most ready to use for this aim

 

I came across the following site:
https://maker.pro/arduino/projects/arduino-liquid-level-meter-with-simple-homemade-sensor

This uses the very cunning method of measuring small capacitances using an arduino (could also be used for any uc with an ADC) and needs no extra hardware. The capavitor to be measued is simply connected between two processor pins.
https://wordpress.codewrite.co.uk/pic/2014/01/21/cap-meter-with-arduino-uno/.

 

.
If You expect the best solution to your problem,
ALL aspects of the project must at least be reasonably outlined,
and preferably described in detail, with pictures, and/or, drawings.

So far you're starving us for information,
~20 gallon water-tank ~18" tall
doesn't say much.

Is this another "Top-Secret" project ?
Will this become a commercial product for-sale to the public ?
Why do You need to know the level of the Water in the Tank ?
How much accuracy is required ?
How long will this setup be required to reliably operate without maintenance or repair ?
Is the Tank under pressure ?
What is the Tank made out of ?, Welded-Stainless-Steel ?, Polypropylene ?, Cardboard ?
Is the Water Hot ?
Does the Water contain any Chemicals ?
Must all holes in the Tank enter from the top ?,
or, can a hole be drilled in the side or bottom ?
Will the Tank be in a Hostile-Environment that is likely to be subjected to physical abuse or damage ?

C'mon, throw us a bone at least.
.
.
.

This is a simple water tank holding cold water; the size could change, so looking towards the laser, ultrasonic solution.
The accuracy does not need to be very accurate, as we wish to display the gauge as a percentage rather than mm.

 

It has a small water tank, maybe 80L max height 0.5 meters.

What is the tank made of?

The possible choices of sensor differ with different tank construction, including what is is made of. Is it metal or plastic?

 

You still have provided the very minimum of information.
Is the Tank sealed ?,
Is the Tank under Pressure ?, or open to the atmosphere ?

Unless the surface of the Water remains still and perfectly-flat,
an Ultrasonic, or Laser-based detector, may have issues with intermittent readings.

And, now knowing that the Tank is likely to only be ~18"-deep,
my suggestion in post-3 of using an automotive MAP-Sensor,
will probably not produce enough resolution to be useful,
but there are certainly Air-Pressure-Sensors that are rated for far less than ~14.7-psi.
Such as this one ........
.
.
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