425.Web Server for ESP32/ESP8266 Relay Modules Built with the Arduino IDE (1, 2, 4, 8, 16 Channels) ESP8266 NodeMCU Web Server that has the capability of controlling any relay module. We will develop an ESP32/ESP8266 Web Server that is

responsive on mobile devices and that can be accessible from any device in your local network that has a browser installed on it. A relay is a switch that is electrically operated, and just like any other switch, it can be switched on or off to either allow electricity to pass through it or prevent it from doing so. It is possible to control it with low voltages, such as the 3.3V that is supplied by the ESP GPIOs, and it also gives us the ability to manage high voltages, such as 12V, 24V, or the mains voltage (230V in Europe and 120V in the US). There is a variety of relay hardware available, each with its own distinct number of channels. There are relay modules available with a single channel, two channels, four channels, eight channels, and even sixteen channels. The number of outputs you can control is directly proportional to the number of channels available. Control Relay Modules with Multiple Channels using an ESP32/ESP8266 Web Server You can control an unlimited number of relays via web server with the help of this code for the web server, regardless of whether the relays are set up to be generally opened or normally closed. To determine the number of relays

you wish to manage and the assignment of their pins, all that is required is a simple update to a few lines of code. Wiring a Relay Module to an ESP Board The goal of this example requires us to operate five different relay channels. Following the instructions provided in the following set of schematic diagrams, connect the ESP boards to the relay module. Caution: the majority of relay projects involve working with mains voltage. Inappropriate use may result in severe harm. In the event that you are not familiar with mains voltage, you should seek the assistance of someone who is. Make sure that everything is removed from mains voltage before you

begin programming the ESP or wiring your circuit. You also have the option of controlling 12V appliances with a power source that operates at 12V.

After you have finished making the required adjustments, you will need to upload the code to your ESP. Launch the Serial Monitor at a baud rate of 115200, and after that, click the ESP RST button to obtain the device's IP address (make sure that you circuit is unplugged from mains voltage). To gain access to the web server, launch a web browser on your local network, and type the ESP IP address into the address bar. You should end up with something that looks like this, complete with the same number of

buttons regardless of how many relays you define in your code. You may now use your smartphone to control your relays remotely by pressing the buttons. Enclosure for the Purpose of Safety For your final project, enclose the relay module and ESP inside an enclosure to prevent AC pins from being exposed. Applications for the ESP8266 Intelligent security equipment, such as surveillance cameras and smart locks. Energy-efficient home appliances, such as air conditioners and heaters. Intelligent industrial devices, such as Programmable Logic Controllers (PLCs), among others (PLCs) Among intelligent medical gadgets are wearable health monitors.