Example Code for Arduino-Solenoid Valve Control

Hardware Preparation

• DFRduino UNO R3 x 1
• Solenoid Valve DN15 x 1
• Gravity: Digital 5A Relay Module(Arduino Compatible) x 1
• PC x 1
• Dupont lines x n

Software Preparation

• Arduino IDE

Wiring Diagram

• Pin definitions of the connecting terminal of the relay module:

  • NC: normally closed terminal
  • NO: normally open terminal
  • N/A: not available
  • COM: common terminal

• Connect the control terminal of the relay module to Arduino: green wire goes to the digital pin 3; red wire to 5V pin; black wire to GND;

• Connect the connecting terminal of the relay module to external power supply and solenoid valve: COM port goes to the positive pole of external power supply; NO port to red wire of the solenoid valve; NC port to blue wire of the valve;

• Connect the yellow wire of solenoid valve to the negative pole of the external power.

There is an open/close indicator on the solenoid valve: it displays | when the valve is closed, and — when the valve is open.

The circle at the right-lower corner of the solenoid valve is an Off/On switch, pull it out gently and then we can close or open the valve manually.

Sample Code

Install the Arduino IDE software.

Open the compiling environment of the Arduino IDE, and upload the following codes:

`/***************************************************
Digital Relay Module  (Arduino & Raspberry Pi compatible)
 
***************************************************/
/***************************************************
//Arduino Sample Code //www.DFRobot.com 
//Last modified on 24th January 2019 by WWZ 
//This code has been updated to work with the sample code provided in the Wiki 
****************************************************/ 
/***********Notice and Trouble shooting***************
1.Beware of electric shock and burn out the circuit board.
2.The input voltage of this module is 2.8~5.5V.              
****************************************************/                      //All the above instructions are based on Digital Relay Module

const int RelayPin = 3;                   
       
void setup() {
   Serial.begin(9600);   
  pinMode(RelayPin, OUTPUT);
} 
void loop() {
  if(Serial.read()=='o'){

     digitalWrite(RelayPin, HIGH);   //Turn on  
     Serial.println("open");
     delay(100);
  }
   if(Serial.read()=='f'){

     digitalWrite(RelayPin, LOW);   //Turn off   
     Serial.println("close");
     delay(100);
  }
}`

Result

Input "o" in the Arduino IDE serial monitor input field, then an "open" will be displayed on its display interface, and the solenoid valve is open; Input "f", it will diaplay "close" and the valve will be closed.