Simple Water Sensor

I will Teach you how to make a simple water sensor circuit

Step 1: Gather Parts

Parts List
1 General Purpose NPN Transistor $0.10
1 50K Trimpot $0.15
1 47ohm Resistor $0.01
1 LED $0.08
1 Proto Board or You can etch A PCB
1 3 volt power source battery, wall wart, whatever

Comments

[paxipatel]

how it works

[mr_man]

I like that you put the 22k resistor in "Step 6", and this can be used in the circuit in "step 2" as well. It reduces the probe current, and protects the transistor in the event that the probe electrodes touch each other and short, and reduces the chance of electrolysis generating gas bubbles on the probe electrodes. Also to reduce electrolysis, you could just use 1.5 volts across the probes

Also with a 12 volt supply, you'll want use a higher value resistor than 330 ohms on the LED.

The circuit will probably work without the potentiometer.

[sala89]

how much cost of this project in india

[manjotmessi]

please give me a detailed process of fuctioning of a transisitor in a water level indicator project.

[mboruah]

is any other option not available,i m really not getting it.........

[sahilaggarwal]

here transistor is used for amplification ??????
and why only BC547 OR 548 is used???

[Cyberscann54]

I know I have bad hand writing but it also says any NPN transistor will work

[jpsailr]

After many attempts to make a circuit like this, I gave up. Reason: when current flows through water from one plate to another, gas builds up on the sensor plates and the conductivity of the water reduces until it is undetectable, over 10 megohms within minutes. So if you're not there right when it happens, you will miss it. I solved this by creating a circuit which would put an AC current on the sensor plates. This continually purges the plates of gas and keeps the resistance through the water to less than 100 Kohms - very useable. This test ran for over 4 hours with no loss of conductivity. Now I successfully use it to detect bilge water as soon as it happens, or water on the basement floor. I will submit a project when I get it written up.

[MarleneL]

I am working on a hybrid hot water system and need something like what you are describing... can you please forward me some more information on it please!! Thank you.

[eng_tako]

thank you very much you help me alot

[wonderingoutloud]

Assuming clean water, zero turbulence, very small inflow related to volume, could I get 1/32 inch level gage accuracy? In other words, under perfect conditions, what accuracy could one expect?

[Cyberscann54]

it is a circuit designed to give you a visual alert that you need to fill you water tank in a vehicle accuracy is not part of its implementation being cheep and simple is. If you wish to have a sensor circuit that is that accurate this is not the way to go. Why do you need such accuracy what are you trying to build ???

[palabuto]

do you have the c-language for this project

[Zhelnot]

are you done with this thing??

[geniusgippy]

can nybody eloborate on which HHO cell to use!!!

[Cyberscann54]

I would recommend a dry cell the circuit would be placed on the water fill tank

[mathew086]

Hey... I find this one soo interesting n simple that i am planning to try oit put once. but i have a small question? How much current does the circuit consume for one time function. meaning if the circuit detects water how much currents is consumed by the circuit from the 12 V battery??? thanksss

[jonoxer]

That's pretty easy to figure out with Ohm's Law. There are two paths that current will take through the circuit: the first is through the LED and into the collector of the transistor, and the second is through the probes, the water itself, and the 22K resistor. The current through the LED part of the circuit will be about 36mA, and assuming the water has perfect conductivity (it definitely doesn't, but that's a worst-case scenario) the current through the probes will be under 1mA. In other words, trivial.

[stephenniall]

oo very cool and underated

[DarkAngel09]

Seems like a really cool project I may have to try it out. We have a sensor project in school to do I may use this project for it. Ill send you the results if you are interested.

[the man gadget]

PS electrolyte is a good move too...baking soda is a good start.....

[the man gadget]

I have built some equivalents to this and the results are OK but not great...look up the dry cell version..it is more complicated but the results far better for me so far at 1Ltr/Min @12v/5A

[vancecook7]

If anyone has built and tested this in an actual cell, please let post the results here. I am curious if foam may conduct enough to keep the LED from lighting when the water level drops but cell is still in operation. If the cell is in a vehicle, do corners trigger the circuit?