SIMPLE SOIL MOISTURE SENSOR – ARDUINO PROJECT

This is a simple arduino project for a soil moisture sensor that will light up a LED at a certain moisture level. It uses Arduino Duemilanove microcontroller board. Two wires placed in the soil pot form a variable resistor, whose resistance varies depending on soil moisture. This variable resistor is connected in a voltage divider configuration, and Arduino collects a voltage proportional to resistance between the 2 wires.


Insert the 2 probes (wires, pcb) in the dry soil and measure the resistance value and then pour water and measure it again.
Use a mid value for the resistor (eg: 50kΩ for 100kΩ in dry soil and 10kΩ in wet).

The other method to find the resistor’s value is to try different values or use a potentiometer. Insert the probes into the soil that has the desired moisture when to light up the LED and signal that the plant needs water.

Adjust the potentiometer and see the point at which it starts to light. Measure the potentiomenter current value and replace it with a fixed resistor.

Arduino soil moisture sensor schematic

Project source code

const int VAL_PROBE = 0; // Analog pin 0
const int MOISTURE_LEVEL = 250; // the value after the LED goes ON

void setup() {
Serial.begin(9600);
}

void LedState(int state) {
digitalWrite(13, state);
}

void loop() {
int moisture = analogRead(VAL_PROBE);

Serial.println(moisture);

if(moisture > MOISTURE_LEVEL) {
LedState(HIGH);
} else {
LedState(LOW);
}
delay(100);
}

Views: 3368

Latest Activity

Marcelo Rodrigues and swapnil are now friends
Tuesday
Marcelo Rodrigues replied to swapnil's discussion Tiny 85 based Thermometer
"Dear Swapnil, Since you don't have any experience with programming you should consider start…"
Monday
swapnil posted a discussion

Tiny 85 based Thermometer

Hi, can any one guide me how to make the tiny 85 based Thermometer which will glow the LED…See More
Sunday
Spyros Svoronos is now a member of GarageLab (arduino, electronics, robotics, hacking)
Sunday
K Biju is now a member of GarageLab (arduino, electronics, robotics, hacking)
Nov 29
Profile Iconswapnil and Yasser joined GarageLab (arduino, electronics, robotics, hacking)
Nov 28
udit is now a member of GarageLab (arduino, electronics, robotics, hacking)
Nov 25
Aqeel munir is now a member of GarageLab (arduino, electronics, robotics, hacking)
Nov 23
Profile IconSubbu and Graymon Cadiente joined GarageLab (arduino, electronics, robotics, hacking)
Nov 21
Tim Walller is now a member of GarageLab (arduino, electronics, robotics, hacking)
Nov 18
Dmitry Slepov posted a blog post

Open Platform Communications Server from Tibbo

OPC stands for «Open Platform Communications» that is a set of specifications and standards for…See More
Nov 17
Hrithik Bansal is now a member of GarageLab (arduino, electronics, robotics, hacking)
Nov 17
Martin Tavarez is now a member of GarageLab (arduino, electronics, robotics, hacking)
Nov 14
Brian Sivils is now a member of GarageLab (arduino, electronics, robotics, hacking)
Nov 7
Keren Fi is now a member of GarageLab (arduino, electronics, robotics, hacking)
Nov 3
Profile IconHENRY NUNES and evilhacker joined GarageLab (arduino, electronics, robotics, hacking)
Oct 31
Profile IconJames Pearce and caca joined GarageLab (arduino, electronics, robotics, hacking)
Oct 27
Profile IconWilliam Johnson and Todd Enger joined GarageLab (arduino, electronics, robotics, hacking)
Oct 24
Carlos Kwiek posted a blog post

ESP8266_MQTT_LAMP_ON_OFF

Turning on and off a lamp on the internet and smartphone using ESP8266 with MQTT languageThank you…See More
Oct 24
Avtar Singh is now a member of GarageLab (arduino, electronics, robotics, hacking)
Oct 20

© 2016   Created by Marcelo Rodrigues.   Powered by

Badges  |  Report an Issue  |  Terms of Service