Example Code for Arduino-Relay Control

Hardware Preparation

• DFR0473 Gravity: Digital 10A Relay Module (SKU:DFR0473 x 1)
• DFRduino UNO R3 with IO Expansion Shield and USB Cable A-B (SKU:DFR0216-2 x 1)
• 1.5V AA battery (or other power supply) x 2
• LED lights (or other electrical equipment)
• Jumper wires

Software Preparation

• Development Tool: Arduino IDE (version unspecified). Download link: Arduino IDE

Wiring Diagram

Other Preparation Work

1. Be ware of electric shock and burn out the circuit board.
2. The input voltage of this module is 2.8 ~ 5.5V.

Sample Code

/***************************************************
 Digital Relay Module  (Arduino & Raspberry Pi compatible)
 <https://www.dfrobot.com/wiki/index.php/Gravity:_Digital_Relay_Module_(Arduino_&_Raspberry_Pi_Compatible)_SKU:_DFR0473#Connection_Diagram>

***************************************************/
/***************************************************
 This example shows how to use 3V Relay Module(DFR0473).
 Created 2016-12-20
 By Free Li <[email protected]>

 GNU Lesser General Public License.
 See <http://www.gnu.org/licenses/> for details.
 All above must be included in any redistribution
****************************************************/
/***********Notice and Trouble shooting***************
1.Be ware of electric shock and burn out the circuit board.
2.The input voltage of this module is 2.8 ~ 5.5V.
****************************************************/


const int RelayPin = 2;

void setup() {
  pinMode(RelayPin, OUTPUT);
}
void loop() {
  digitalWrite(RelayPin, HIGH);   //Turn on relay
  delay(1000);
  digitalWrite(RelayPin, LOW);   //Turn off relay
   delay(1000);
}

Result

• The LED will change its state every second, and you will hear a loud pop at the same time.
• When the module gets HIGH signal: NO terminal connects to COM port, LED is ON.
• When the module gets LOW signal: NO terminal disconnects from COM port, LED is OFF.