Module parameter
Size: 37.3mm * 25.6mm; With M3 mounting hole
Working voltage: DC 5V-12V
Relay load capacity: 10A 250VAC 10A 125VAC 10A 30VDC 10A 28VDC

Pin definition
VCC and GND power supply positive and negative poles, busbar is ESP-01/01S interface, and key is reset key
NC relay normally closed end, COM relay common end, NO relay normally open end

Instructions
Use the ESP-01/01S-key downloader to download the Arduino example program for the ESP-01/01S module, and click
Open the Arduino serial port monitor to view the IP address
Insert ESP-01/ESP-01S into 2 * 4 Pin busbar
Power supply is connected to VCC GND (2.54mm row pin)
Connect the computer or mobile phone to the router (the same as the router connected to ESP-01S), open the browser, enter the IP address printed out by the serial port, and then operate the relay to pull in and release