How to Wire a Simple 120v Electrical Circuit (with Pictures) METHODTIPSWARNINGSTHINGS NEEDED Turn off the power feeding the panel you are going to be working in. It may help to take a few minutes to familiarize yourself with all of the tips in the related wikiHow article on "How to Master Do It Yourself Electrical Safety". Shut off all the individual circuit breakers in the panel and then shut off the main switch that supplies power to the panel. This is preferable as it is much This wikiHow is about wiring a simple electrical circuit. It doesn't cover the following information, whiSee all 37 steps on wwwhow72%(61)Published: Aug 01, 2006Views: 454K Wiring Diagrams for Electrical Receptacle Outlets - Do-it Wiring Diagram for a 20-Amp 120-Volt Duplex Receptacle A 20 amp, 120v duplex receptacle outlet like this should be installed in a circuit using 12 awg cable and a 20 amp circuit breaker. These receptacles are usually found in kitchen wall outlets where two branch circuits are needed to serve small appliances and a refrigerator separately.