11+ 3 Pin Rocker Switch Wiring Diagram. Snap it into a 3/4 inch hole and you're good to go. Here is a wiring diagram of how the internal switching and lamp wiring is connected.
Now when i want to turn on/off the arduino, i just plug/unplug the wire to the vin pin which is not convenient. Try what i said and switch the terminals 2 and 3 (wouldn't be the first time a manufacturer's wiring diagram was incorrect). Connect the unused terminal to neutral.
You may need to reference datasheets, schematics.
11+ 3 Pin Rocker Switch Wiring Diagram. Snap it into a 3/4 inch hole and you're good to go. The round rocker switch has different switches inside of it then the rectangle rocker switch. As you see in the 2 way switch diagram below, you will find that the phase/live. It is connected to an old computer 320w power supply, used to power it on and off.