Comments on: Soil Moisture Sensor Circuit Explained

By: Thomas W.

Thomas W. — Fri, 03 Feb 2012 11:38:04 +0000

@Hazil: Yes – the voltage across R2 could be measured by the input of an opamp comparator and then a switch actuator could be added like in this circuit: http://66pacific.com/ph/phschematic.htm (Valve solenoid = relay coil)
An extra 555 IC can work as a timer IC: http://www.kpsec.freeuk.com/555timer.htm#monostable

By: hazil

hazil — Mon, 23 Jan 2012 13:07:51 +0000

sir, can relay switch and timer can be added to this circuit?

By: Thomas W.

Thomas W. — Mon, 23 Jan 2012 10:11:19 +0000

@Hazil: I think you can control 1-Wire devices with the Arduino board. I’m using NSLU2, but a SheevaPlug or FitPC should be able to control it to.
http://diagramtips.com/2011/08/31/automatic-temperature-measurements-using-nslu2/

By: hazil

hazil — Fri, 20 Jan 2012 16:25:43 +0000

sir..how i want to control the soil moisture sensor?can i use the microcontroller?can u recommended what type of microcontroller?my project is about solar system for irrigation that using soil moisture sensor..

By: Thomas W.

Thomas W. — Mon, 27 Jun 2011 07:55:51 +0000

@Mpho: What device / component will you be using to control the water flow? Some kind of pump or valve? I plan on using an electric drill pump (Gardena, 1,700 l/h @ Ø 13 mm hose, 3 bar) connected to a sprinkler or soaker hose depending on the crop (some crops are sensitive to water on their leaves due to blight.)

By: mpho

mpho — Wed, 15 Jun 2011 08:51:43 +0000

hi Tom,its Mpho in Botswana,one country in southern Africa..i need some assistance from you,i want to design a circuit which control the moisture content,pliz send me some possible circuit diagrams

By: Thomas W.

Thomas W. — Tue, 05 Apr 2011 15:25:39 +0000

@Riteeka: What type of controller do you want to use, and what does your circuit look like? Do you have a schematic? What sensor are you using?

By: riteeka

riteeka — Fri, 01 Apr 2011 17:20:43 +0000

I want measure soil moisture n give its output to controller.I had made one circuit but it is giving me output even at low humidity.I want to compare present moisture value with threshold value.how can I do that?.thank you for giving your time and consideration.

sincerely,

Riteeka

By: Thomas W.

Thomas W. — Tue, 27 Jul 2010 12:02:25 +0000

@RD Pawar: Please take a look at this post: http://happyfarming.com/2008/12/23/soil-moisture-sensor/

By: RD Pawar

RD Pawar — Tue, 27 Jul 2010 09:46:37 +0000

I require to measure water content at root zone of plants. What material shall be used as a probe. whether still wires will work.