Mini 3A Relay Unit
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RELAY, as its namesake, is a M5Unit that implenments a Relay functions. Relay can be used as an electrically operated switch, uses an electromagnet to mechanically operate a switch,to where it is necessary to control a large power load circuit by a separate low-power signal, like a digital signal output from a mircoprocessor. Up to 30V DC and 220V AC.

There are 3 pins named: ON, OFF, COM. You can program to make COM connect to ON or OFF, just by high and low out put of a digital GPIO.

Product Features

  • Single-BUS control
  • Up to 3A @ 30 V DC or 220 V AC
  • Software Development Platform: Arduino, UIFlow(Blockly,Python)
  • Two Lego-compatible holes

Kit includes

  • 1x RELAY Unit
  • 1x Grove Cable
  • 1x 3.96 soket


  • Remote control of high-power appliances, such as refrigerators, Air Conditioners, TVs, etc.



1. Arduino IDE

The code below is incomplete. To get complete code, please click here.

#include <M5Stack.h>

void setup() {
  M5.Lcd.setTextColor(YELLOW, BLACK);
  //disable the speak noise
  dacWrite(25, 0);
  pinMode(26, OUTPUT);// RELAY Pin setting

void loop(void) {
  digitalWrite(26, HIGH);// RELAY Unit work
  digitalWrite(26, LOW);// RELAY Unit stop work

2. UIFlow

To get complete code, please click here.



More information




M5Core(GROVE B) GPIO36 GPIO26 5V GND RELAY Unit / RELAY Controlling Pin 5V GND


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