SP8266 Series – ESP-01S Control Relay Module

In smart home applications, we may need to control high-voltage devices that use AC power, such as lights, fans, or other household appliances. However, microcontrollers generally operate on a direct current voltage of 5V (DC5V) and cannot directly control these high-voltage electrical appliances.
At this point, a relay module is needed. Relays are inexpensive and easy to connect, making them ideal for small IoT applications that require switching between appropriate amounts of AC or DC power. If wireless remote control is required, the ESP-01S relay module is undoubtedly the best choice.

We will guide everyone to complete the code writing of the ESP-01S relay module, access the IP address of the core controller ESP8266 microcontroller through a browser, and control lights or other devices in the web interface.

• Hardware preparation

ESP-01S

Relay module

• Development Environment – Arduino IDE

Download link: Software | Arduino

You also need to install the software package corresponding to ESP8266, and enter the following URL as the management URL for other development boards in Arduino IDE

https://arduino.esp8266.com/stable/package_esp8266com_index.json

The specific operation is to first select “File” in the menu bar of Arduino IDE, and then click “Preferences”.

Paste the URL into the input box next to the Additional Boards Manager URLs and click “OK” to save.

Click on the “Development Board Management” icon in the sidebar, enter “ESP8266” in the search box, and the software package for ESP8266 will appear. Click “INSTALL” to install it.

After successful installation, restart the Arduino IDE and you can find the “Generic ESP8266 Module” in the development board list.

• Hardware connection and effect display

The 3PIN terminal only needs to be connected to the COM terminal (common terminal) and the NO terminal (normally open contact), as shown in the following figure.

After completing the wiring, on the same local area network device (phone or computer), open a browser and enter the IP address of ESP-01S in the address input field. You can see the Wed interface of ESP-01S.