How to Use 4 Channel 30a 5V Relay: Examples, Pinouts, and Specs

The 4 Channel 30A 5V Relay (YYG-4) is an electrically operated switch that allows a low-power signal to control a high-power circuit. This relay module can control up to 30 amps of current using a 5V signal and can switch four different circuits independently. It is commonly used in applications such as home automation, industrial automation, and various DIY projects.

• Home automation systems
• Industrial control systems
• Motor control
• Lighting control
• DIY electronics projects
• Arduino and other microcontroller projects

1. Power Supply: Connect the VCC pin to a 5V power supply and the GND pin to the ground.
2. Control Signals: Connect the IN1, IN2, IN3, and IN4 pins to the digital output pins of a microcontroller (e.g., Arduino).
3. Load Connections: Connect the load to the COM, NO, and NC terminals of each relay channel as required by your application.

• Ensure that the power supply voltage is stable and within the specified range (5V DC).
• Use appropriate heat sinks or cooling mechanisms if the relay is switching high currents frequently.
• Avoid switching inductive loads without proper flyback diodes to prevent voltage spikes.
• Ensure that the control signals are properly isolated from the high-power circuit to prevent damage to the microcontroller.

Arduino UNO          Relay Module
-----------          -------------
5V         --------> VCC
GND        --------> GND
D2         --------> IN1
D3         --------> IN2
D4         --------> IN3
D5         --------> IN4

// Define relay control pins
const int relay1 = 2;
const int relay2 = 3;
const int relay3 = 4;
const int relay4 = 5;

void setup() {
  // Initialize relay control pins as outputs
  pinMode(relay1, OUTPUT);
  pinMode(relay2, OUTPUT);
  pinMode(relay3, OUTPUT);
  pinMode(relay4, OUTPUT);

  // Set all relays to off state (HIGH)
  digitalWrite(relay1, HIGH);
  digitalWrite(relay2, HIGH);
  digitalWrite(relay3, HIGH);
  digitalWrite(relay4, HIGH);
}

void loop() {
  // Example: Turn on Relay 1 for 2 seconds, then turn it off
  digitalWrite(relay1, LOW); // Turn on Relay 1
  delay(2000);               // Wait for 2 seconds
  digitalWrite(relay1, HIGH);// Turn off Relay 1
  delay(2000);               // Wait for 2 seconds

  // Repeat for other relays as needed
}

1. Relay Not Switching: Ensure that the control signal voltage is correct and that the relay module is properly powered.
2. High Current Load Not Working: Verify that the load current does not exceed the relay's maximum current rating (30A).
3. Microcontroller Resetting: This could be due to voltage spikes from inductive loads. Use flyback diodes to protect the microcontroller.

• Check Connections: Ensure all connections are secure and correct.
• Verify Power Supply: Make sure the power supply is stable and within the specified voltage range.
• Use Flyback Diodes: For inductive loads, use flyback diodes to prevent voltage spikes.
• Isolate Control Signals: Use optocouplers or other isolation techniques to protect the microcontroller from high-power circuits.

By following this documentation, users should be able to effectively utilize the 4 Channel 30A 5V Relay (YYG-4) in their projects, ensuring reliable and safe operation.