how do you wire a 240 volt breaker gfci | The Home Depot We have a great video that goes through a step by step instructions on how to install a GFCI breaker. Click on the image below, and it will take you directly to it. As long as your main panel power is off, this is a install any DIY'er can easily do. Wiring Diagrams for Electrical Receptacle Outlets - Do-it Wiring a 50-Amp, 240-Volt Appliance Outlet. This wiring diagram is used for 50 amp appliance outlet. The receptacle should be wired to a dedicated 50 amp circuit breaker using 6 awg cable. The 50 amp circuit is required for new installations of some large appliances requiring 240 volts.