FC-28 Soil Moisture Sensor Module

Description

FC-28 Soil Moisture Sensor Module

The FC-28 measures soil moisture by sensing electrical conductivity between its two probes. The module provides analog and digital outputs and can be used with microcontrollers such as Arduino.

Specifications

• Operating voltage: 3.3–5 V DC
• Operating current: 15 mA
• Digital output: 0–5 V; trigger threshold adjustable with the onboard potentiometer
• Analog output: 0–5 V according to the moisture level
• PCB dimensions: 3.2 × 1.4 cm
• Design: LM393-based

How it works

The FC-28 measures resistance between two probes inserted in the soil. As the soil becomes wetter, conductivity rises and resistance falls. The module converts this change into an electrical signal that Arduino can read.

Applications

• Automatic irrigation systems
• Plant and garden moisture monitoring
• Educational and hobby projects

Pinout

• VCC: 3.3–5 V supply
• GND: ground
• AO: analog output
• DO: digital output with adjustable threshold

Using it with Arduino Uno

Basic example

const int sensorPin = A0; // Broche où le capteur est connecté
int sensorValue = 0;


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


void loop() {
  sensorValue = analogRead(sensorPin);
  Serial.print("Niveau d'humidité du sol : ");
  Serial.println(sensorValue);
  delay(1000);
}

Advanced example with I2C LCD

#include <LiquidCrystal_I2C.h>


LiquidCrystal_I2C lcd(0x27, 16, 2);
const int sensorPin = A0; 
int sensorValue = 0;


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


void loop() {
  sensorValue = analogRead(sensorPin);
  lcd.setCursor(0, 0);
  lcd.print("Humidite: ");
  lcd.print(sensorValue);
  lcd.print("%");
  delay(1000);
}

Advanced-example wiring

• FC-28 VCC: Arduino 5 V
• FC-28 GND: Arduino GND
• FC-28 AO: Arduino analog input A0
• LCD VCC/GND: Arduino 5 V/GND
• LCD SCL/SDA: Arduino A5/A4

Library installation

For the LCD example, open the Arduino IDE Library Manager and install LiquidCrystal_I2C.

Keywords: FC-28 soil moisture sensor, soil humidity, hygrometer module, analog soil sensor, Arduino irrigation project.