Why Some Outlets Are Installed “Upside Down”: A Small Secret Many People Don’t Know

is that sometimes only one half of the outlet is controlled by the switch. For example, the top plug may turn on and off with the wall switch, while the bottom plug always stays powered. That is convenient: you can plug a lamp into the switched part, while using the always-on part for a charger, clock, router, or another device.

But there is an important continue reading …