Sonoff is an affordable solution for home automation (home automation). This switch is based on the well-known ESP8266 and works over a WiFi connection with which devices can be switched on and off via the cloud. By means of the phone application (iOS and Android) eWeLink, this WIFI switch can be switched anywhere in the world, you don't even have to be at home!The Sonoff SV (Safe Voltage) works like the normal Sonoff switch, but works at a lower (safe) voltage (5V to 24V). The jumper is used to connect the input voltage to the relay, but by removing it, AC / mains voltage can also be switched. The board also has I / O available to program the ESP8266 itself.