This article will explore the workings of a relay module and provide a detailed guide on how to interface a single channel relay module with an Arduino.

SIM900-Arduino-Relay-Control This project uses GSM Module (SIM900) with Arduino to switch Relay state by SMS OR CALL.

Welcome to my quick review of an inexpensive 2-channel 5V relay module controlled via RS485 bus utilizing Modbus RTU protocol. As claimed by some online sellers, this easy-to-get Modbus RTU 2-Channel ...

As per the source code, when the control pins of the relay module receive the LOW signal the respective relay will turn on and the relay will turn off for the HIGH signal in the control pin. I have ...