Arduino Relay Module Example

Wiring

Full code

const int relayPin = 7;

void setup() {
  pinMode(relayPin, OUTPUT);
}

void loop() {
  digitalWrite(relayPin, HIGH);
  delay(2000);
  digitalWrite(relayPin, LOW);
  delay(2000);
}

How it works

This lesson matches the page title and gives a clean starting point for this exact example.

Common mistakes

Check board selection, wiring, libraries, power supply and serial monitor baud rate.