const int Relay_1Chan = 13;
void setup(){
  Serial.begin(115200);
  pinMode(Relay_1Chan, OUTPUT);
}

void loop(){
  digitalWrite(Relay_1Chan, HIGH);
  Serial.println("LED ON");
  delay(3000);

  digitalWrite(Relay_1Chan, LOW);
  Serial.println("LED OFF");
  delay(3000);
}