How To Install A GFI (Ground Fault Interrupt) Breaker
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 Installing a GFI breaker in your main breaker box, as any electrical work, is dangerous should be done by a qualified electrician or professional. This article is for reference only and does NOTadvocate homeowners doing their own wiring. If you have AC power anywhere close to water (outside outlets, kitchens, bathrooms, hot-tubs) then you must install either a GFI breaker or a GFI outlet. Inside the GFI is a sensor that detects changes in current to the appliance or circuit. It does this by comparing the current flowing to the appliance (over the hot wires) and the current flowing from the appliance (over the neutral wire). A change in in the delta current of about 5 milliamperes will trip the breaker within a few hundredths of a second. This is so fast that you might not even feel the juice if you were to short the circuit with your body. This will protect you from an injury to your heart but there is still a danger of a "jerk reflex" or spasm in the muscles during this period. This is not a problem if you are standing on the ground but it is potentially dangerous if you become unbalances on a roof or ladder. Whenever possible, install a GFI outlet and not a GFI breaker. An standard 110V GFI outlet costs about $8 where a breaker costs $30-150. In addition to the cost savings, it is easier to reset an outlet since it is inside your house. If you trip a GFI breaker from your bathroom, you don?t want to go outside to reset it. In some cases, like the hot-tub wiring pictured here, you must have a GFI breaker because the circuit is: -Wired directly to an appliance - 220VAC - Higher current than an outlet can take. GFI INSTALLATION Installation of the GFI breaker is simple. Flip the main breakers to the OFF position before opening the breaker panel. The GFI will install just like a standard breaker with one modification. You must connect the white (neutral) wire from the circuit (appliance) to the GFI Breaker. This wire is shown in purple in the attached illustration. Then connect the white wire pigtail from the GFI breaker to the neutral buss bar. This wire is shown in blue in the attached illustration. When the GFI breaker trips and disconnects the power from the black and red (hot) wires, it will also disconnect the neutral wire.
By disconnecting the hot and neutral wires, the outlets or appliances now have only 1 wire connected (when tripped), the ground (copper with no jacket) wire. Since you cannot complete a circuit with only 1 wire, it makes it very difficult to have an electrical short. Warning: You can still be killed by a circuit protected by a GFI. If you are isolated from the ground and get a good connection on the hot and neutral wire, you can complete the circuit without tripping the GFI. If the power goes through your chest (called the heart path), it will stop your heart. Another advantage of using a GFI outlet is that you can test the outlet using an inexpensive GFI test tool that plugs into the outlet and has a button that causes a short. These tools cost about 10 dollars at the local home improvement store and also includes light to indicate the outlet is wired correctly. There is no easy way to test a GFI breaker that wired directly to an appliance like a hot tub. "Testing" breakers by applying a load may give an instantaneous picture of the performance of individual breakers but it does not predict their performance when a real safety problem occurs (overcurrent). More important, except if performed by a very expert person, in-place testing is very dangerous and could start a fire fire or cause serious injury. THIS WORK SHOULD BE DONE BY A EXPERIENCED PROFESSIONAL...... Electrical work is highly dangerous. Let us help you find a great Electrician to do this job for you. Need More Information? Check out our other articles on home wiring and electrical projects. The information on this site is provided for reference only and is provided "AS IS", "AS AVAILABLE" with no guarantee of accuracy. Information comes with no warranties, express or implied. Use the information from this site at your own risk. See our disclaimer for more details. |