![\"moisture](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2016\/07\/moisture-sensor.jpg?resize=350%2C368&quality=100&strip=all&ssl=1\")
<\/p>\nThe soil moisture sensor or the hygrometer is usually used to detect the humidity of the soil. So, it is perfect to build an automatic watering system or to monitor the soil moisture of your plants.<\/p>\n
The sensor is set up by two pieces: the electronic board (at the right), and the probe with two pads, that detects the water content (at the left).<\/p>\n
<\/p>\n
The sensor has a built-in potentiometer for sensitivity adjustment\u00a0of the digital output (D0), a power LED and a digital output LED, as you can see in the following figure.<\/p>\n
![\"labeled](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2016\/06\/labeled-sensor.png?resize=650%2C323&quality=100&strip=all&ssl=1\")
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You can also read this guide for the Rain Sensor FC-37 or YL-83 with Arduino<\/a>.<\/p>\n The voltage that the sensor outputs changes accordingly to the water content in the soil.<\/p>\n When the soil is:<\/p>\n The output can be a digital signal (D0) LOW or HIGH, depending on the water content. If the soil humidity exceeds a certain predefined threshold value, the modules outputs LOW, otherwise it outputs HIGH. The threshold value for the digital\u00a0signal can be adjusted using the potentiometer.<\/p>\n The output can be a analog\u00a0signal and so you\u2019ll get a value between 0 and 1023.<\/p>\n This is a simple example for you to understand how you can use the soil moisture sensor in your projects with Arduino.<\/p>\n In this example, you\u2019ll read the analog sensor\u00a0output values using the Arduino and print those readings in the Arduino IDE serial monitor.<\/p>\n For this example, you\u2019ll need the following components:<\/p>\n You can use the preceding links or go directly to MakerAdvisor.com\/tools<\/a> to find all the parts for your projects at the best price!<\/p> Wiring your sensor to the Arduino is pretty simple:<\/p>\n To complete the project, follow these schematics:<\/p>\n Upload the following sketch to your Arduino board:<\/p>\nHow does it work?<\/h2>\n
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![\"soil](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2016\/07\/soil-moisture-sensor-e1467578282801.png?resize=1104%2C601&quality=100&strip=all&ssl=1\")
<\/p>\nExample: Soil Moisture Sensor with the Arduino<\/h2>\n
Parts required<\/h3>\n
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![](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2017\/10\/header-200.png?w=1200&quality=100&strip=all&ssl=1\")
<\/a><\/p>\nPin Wiring<\/h3>\n
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\n Pin<\/td>\n Wiring to Arduino Uno<\/td>\n<\/tr>\n \n A0<\/td>\n Analog Pins<\/td>\n<\/tr>\n \n D0<\/td>\n Digital Pins<\/td>\n<\/tr>\n \n GND<\/td>\n GND<\/td>\n<\/tr>\n \n VCC<\/td>\n 5V<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n Schematics<\/h3>\n
![\"moisture](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2016\/07\/moisture-sensor-fritzing.jpg?resize=834%2C393&quality=100&strip=all&ssl=1\")
<\/p>\nCode<\/h3>\n
\/*\n \n All the resources for this project:\n http:\/\/randomnerdtutorials.com\/\n \n*\/\n\nint rainPin = A0;\nint greenLED = 6;\nint redLED = 7;\n\/\/ you can adjust the threshold value\nint thresholdValue = 800;\n\nvoid setup(){\n pinMode(rainPin, INPUT);\n pinMode(greenLED, OUTPUT);\n pinMode(redLED, OUTPUT);\n digitalWrite(greenLED, LOW);\n digitalWrite(redLED, LOW);\n Serial.begin(9600);\n}\n\nvoid loop() {\n \/\/ read the input on analog pin 0:\n int sensorValue = analogRead(rainPin);\n Serial.print(sensorValue);\n if(sensorValue < thresholdValue){\n Serial.println(" - Doesn't need watering");\n digitalWrite(redLED, LOW);\n digitalWrite(greenLED, HIGH);\n }\n else {\n Serial.println(" - Time to water your plant");\n digitalWrite(redLED, HIGH);\n digitalWrite(greenLED, LOW);\n }\n delay(500);\n}\n<\/code><\/pre>\n\t