Before we begin understanding the GFCI outlet wiring diagram, we should understand what GFCI does! As you can see, a Ground-fault circuit interrupter, or GFCI, is a fast-acting circuit breaker designed to shut off major electric power in the event of a ground fault within as little as 1/40 of a second. As you can see from the wiring diagram below, such GFCIs are required in basements, laundry rooms, garages, and areas where the water source is nearby. With the help of EdrawMax, you can easily create such wiring diagrams and share them with your client, so they can understand what you are planning to install and why such outlets are necessary.