A compact 2-channel relay module designed specifically for the ESP8266, and more specifically for the ESP-01 and ESP-01S chips. It is an expanded version of the standard 1-channel controller, offering the ability to control two independent circuits. The module is equipped with a dedicated mounting socket, which facilitates integration without the need for an additional microcontroller on the board. It features additional S1 and S2 inputs as well as GPIO and UART pins, allowing for the connection of external sensors or buttons.

This device serves as a ready-to-use hardware foundation for automation systems. Please note that the communication module that plugs into the socket is not included in the set.

Key Technical Features

• Number of channels: 2 independent relays
• Control microcontroller: dedicated socket for ESP8266 (ESP-01 and ESP-01S chips)
• Maximum relay load: 10 A at 250 V AC or 10 A at 30 V DC
• Logic supply voltage: 5V DC
• Relay section power supply: dedicated screw terminal
• Output configuration: COM, NO, NC (SPDT relay). The middle terminal is NC. Note: On the bottom of the board, the NO terminal is incorrectly labeled as NC.
• Available expansion connectors: S1, S2, RX, TX, RX1, TX1, CLK, DAT, RST
• Physical dimensions: 55 x 45 mm

Example Applications

• Automation of lighting systems in buildings and outdoors
• Remote control of solenoid valves and pump systems in irrigation systems
• Power management for household appliances and electronics
• Integration of physical wall switches and sensors with a wireless network
• Building custom actuators for ESP8266-based IoT projects
• Creating advanced timing circuits and device schedules

Benefits

• High compatibility with open-source firmware such as ESPHome and Tasmota
• Seamless integration with Home Assistant via the MQTT protocol
• Exposed UART communication pins, facilitating flashing of the ESP-01S chip
• Simplified automation project design—no need to solder actuators
• Compact PCB dimensions ideal for installation in dedicated enclosures

Compatibility

• Hardware platforms: up to ESP8266 (ESP-01 and ESP-01S boards)
• Development environments: ESPHome, Tasmota, Arduino IDE
• Smart home systems: Home Assistant, openHAB, Domoticz