Soil moisture sensor

[14dhrumit]

I want to make a soil moisture sensor but i am unable to make it. I surfed internet and i found the image shown below. I made it and i didn't got any type of output and so can anyone suggest me the circuit that really works on +5V or +12V??


https://www.8051projects.net/e107_files/public/1238087580_14263_FT19498_soil_moisture.jpg

 

[pakitos]

hope this will help

http://tuxgraphics.org/electronics/200908/eth-flower-watering.shtml

I have also tried to use a small value of capacitors. Just cut the edge of the capacitor and use instead of the two plate concept of the humidity or moisture sensor.
If extra info is needed do not hesitate to ask

 

[14dhrumit]

I want to measure the moisture content in the ground and not the temperature. Will it be able to help???

OK thank you for this... But what about the programming? I have used soil moisture along with LDR and rain sensor with MCP3204 (ADC) to interface with microcontroller. So how am i suppose to program them??? i am not able to program them...

 

[jayanth.devarayanadurga]

Use a humidity sensor which can tolerate if it is made wet.

 

[14dhrumit]

and how can i make one in order to measure the moisture content of the soil??

 

[jayanth.devarayanadurga]

I said to purchase a humidity sensor which can be immersed in water because your sensor(s) will be in the soil (outside) and it becomes wet when there is rain.

 

[14dhrumit]

But sir, i want it for my project purpose and is it possible to do that???

and besides this, what rain has to do here? I want to measure the soil moisture not the amount of rainwater.

 

[jayanth.devarayanadurga]

Google for moisture sensors.

http://www.decagon.com/products/sensors/soil-moisture-sensors/
http://gardenbot.org/howTo/soilMoisture/

 

[14dhrumit]

I did and i found many...
but the problem is i have to connect them to ADC in order to interface them with the microcontroller. And i don't know how to program them. The ADC i am using is MCP3204 and it measures only upto 4V, so if my output exceeds 4V, i have to divide it by 2. Moreover, i have to display it on LCD and that too in percentage, but i don't know how to program them and that's my biggest problem... Please help in that.

 

[jayanth.devarayanadurga]

Your question was regarding sensor. First find a sensor then only depending upon its output voltage hardware and program can be done. Your ADC can take input of 5V. It is a 12 bit adc. Why don't you use some MCU which has 12-bit adc? Why do you want to use MCP3204? First buy a soil moisture sensor and post its datasheet.

 

[14dhrumit]

The output of my soil moisture is 0.5(min when soil is dry) and 4.7(max in wet soil).

is it possible to program it now??

 

[jayanth.devarayanadurga]

Yes. What about LDR and rain sensor values? Do you have to use 80xx MCUs?

 

[14dhrumit]

Rain sensor gives 4.7V max and 0.5 as min...
LDR gives 17K(3.1V) in dark and 11.5K(2.6 V in full light). I think 89C52 is included in the family of 8052.

 

[jayanth.devarayanadurga]

I need two days time to write the code.

 

[14dhrumit]

Ok, but please do it asap, please.

thank you in advance...

 

[ravimarcus]

I have built soil moisture sensor using capacitance method. The normal resistance method stops functioning after some time due to corrosion.

The output pulse is proportional to the moisture content, that is 0% to 100%. 0% being dry and 100% being dipped in water.

This can be used in a 3 wires or 2 wires system.

It is undergoing practical tests.

Cheers

Ravi

 

[14dhrumit]

can you provide the circuit ?

 

[ravimarcus]

can you provide the circuit ?

I am sorry, this is being launched as a commercial product.

Cheers

Ravi

 

[Teeqa Mohamad]

i want to know the VHDL coding for this moisture sensor when connected to spartan 3e

 

[KhaledOsmani]

Can you please post the circuit you had used, and tell the method in which you had tested it please?