Description
1 Channel 5V Relay Module
A 1-Channel 5V Relay Module is an electronic switching device that allows a low-power microcontroller (like an Arduino, Raspberry Pi, ESP32, etc.) to safely control high-voltage or high-current appliances, such as lights, fans, motors, and pumps. It acts as an electrically operated switch, using a 5V signal to open or close the circuit connected to a higher voltage source (like 220V AC or 12V DC).
Technical Specifications:
-
Operating Voltage: 5V DC
-
Trigger Voltage: 0–2V LOW (active low) to activate the relay
-
Control Signal Voltage: 0–5V (compatible with 3.3V and 5V logic)
-
Relay Type: Electromechanical relay (typically SRD-05VDC-SR-C)
- Number of channels: 1
Pinouts:
Connection with Arduino:
Module |
Arduino UNO |
VCC |
5V |
GND |
GND |
IN |
Pin 7 |
Relay Output terminal(Screw terminals)
Terminal Label |
Description |
COM |
Common terminal (connects to Power or load) |
NO |
Normally Open (Connected to COM when relay is activated) |
NC |
Normally Closed (Connected to COM when relay is Inactive) |
Sample code:
const int relayPin = 7;
void setup() {
// Set the relay pin as OUTPUT
pinMode(relayPin, OUTPUT);
}
void loop() {
// Turn the relay ON (active LOW)
digitalWrite(relayPin, LOW);
delay(1000); // wait 1 second
// Turn the relay OFF
digitalWrite(relayPin, HIGH);
delay(1000); // wait 1 second
}