Hi all,
I need to measure water level of a tank, (on a basket with hieght about 1feel for demonstration) and get that level input to PIC16F877A chip.

There was a solution @
http://www.discovercircuits.com/DJ-C...essh20mon1.htm
but have no idea how to use it on my project.

So guys, please give me an idea on that.

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kani

 

Use an automotive fuel tank sender ( variable resistance ) and Nigel's joystick tutorial.

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If you use electrodes for sensing the problem of scaling electrodes comes into picture if you use a simple dc for sensing. I suggest you can use a toilet flush arm with a float and connect it to a sealed potentiometer and sens the resistance. And sending the data can be done by sending pulses on the power line to sensor controller. Effectively only two twisted wires can be used between overhead tank and the control unit with out any polarity on wires ( wires can be connected in any direction )- Use a bridge on the sensor unit for dc power.

 

This is a common topic.

Use the search on this forum for "water level".

Also try searching the net.

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Dear ClydeCrashKop, mailads, 3v0;

Thank you guys for you posts.

 

hi kasunkg,

just follow three things, i am sure it may help you in your projects..

1. check the resistance of water using multimeter e.g. 10k per cm ... etc.
2. three wires of ground for measuring hi.. medium ... low should be there along with one wire foe 5 v power supply..
3. if possible use ULN 2803 for amplification of current.. though its output is inverted .. but you can use not gate between microcontroller and uln...

 

Hi simrantogether;
Thank you for your idea.
Keep in touch.

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kani

 

the flush arm idea is good.
but there is also nother way is to use reed switches outside the bucket ot tank and use a magnet attached to the inside wall of the tank which can slide over it means you need a plastic base under it.
this mechanism will give you more life but not that precision which u may find in pot resistance.
best of luck
bye

 

nice idea.
even if it indicates the level using some led it will be enough for me.
but the documentation provided with the idea is not clear.
where and what shld i connect the two coils with?

 

i am doing the project of liquid level control usinf pic16f877a. in the circuit diagram we are having dac ad7302 and powe amplifier LM675 but these components are not available in market. can any one sugest any other component for these cpmponents

 

try these links to a three part water tank level meter using a pic

http://www.siliconchip.com.au/cms/A_109005/article.html

http://www.siliconchip.com.au/cms/A_109647/article.html

http://www.siliconchip.com.au/cms/A_109839/article.html

 

This is a quote from the article in third link posted above.
Can anyone describe how one can measure tank level down to 1% accuracy?

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L.Chung

 

How about rigging a passive float, maybe riding up and down a vertical rod at the side of the tank. Then use a Sharp IR range sensor or similar to measure the distance to the float.

I've seen a few articles (like this one) where guys measure salt levels in their water softeners with various IR or ultrasonic sensors. They don't need a float since salt reflects both IR and sound just fine.

Ultrasonic might bounce off liquid ok, I've never tried it. IR might, but probably not. I guess it would depend on what liquid you're measuring too.

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Futz's Microcontrollers & Robotics
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@futz,

Do you or anybody know what method is being used in the article shown in the link above?

Electrode, variable resistor connected to float, IR, ultrasound or what to give 1% accuracy?

To find out one need to subscribe to the article as it did not indicate in the preview webpage.

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L.Chung

 

I didn't subscribe to anything and I can read it fine.

Anyway, he's using a Maxbotix LV-MaxSonar®-EZ1™. They're nice sensors. Inexpensive, easy to use and quite accurate.

I saw another project where they used a Sharp IR sensor. Just google for info.

Ah, here it is! It was David Cook's article at Robot Room. Quite detailed. Here's a link direct to the article.

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Futz's Microcontrollers & Robotics
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