Rain Sensor Alarm System: Never Get Caught Out Again

A Rain Sensor detects the presence of water droplets. When it rains, the sensor triggers an alarm (buzzer) or an action (close a window, retract an awning).

How the Sensor Works

The rain sensor module has a conductive PCB with interleaved traces. When water bridges these traces, the resistance drops significantly. The comparator module reads this change and outputs a digital LOW or an analog value.

Components

• Arduino Uno
• Rain Sensor Module (with comparator board)
• Buzzer
• LED
• (Optional) Servo Motor for automatic window closer

Code Logic

```cpp int rainPin = A0; int buzzerPin = 8;

void setup() { pinMode(buzzerPin, OUTPUT); Serial.begin(9600); }

void loop() { int sensorValue = analogRead(rainPin); Serial.println(sensorValue);

if (sensorValue < 500) { // Threshold (lower = more water) digitalWrite(buzzerPin, HIGH); // ALARM! } else { digitalWrite(buzzerPin, LOW); } delay(100); } ```

Applications

• Automatic clothes drying rack that retracts indoors.
• Smart irrigation systems that pause when raining.
• Alert system for open car windows.

Get Our Kit

Build this project with the Rain Sensor Alarm System kit!