How a GFCI Device Works

A GFCI (Ground Fault Circuit Interruption) device gives you and your family an added layer of protection. While these devices cannot prevent all electrical shocks from occurring, they can generally prevent these shocks from being fatal. A GFCI also helps reduce the risk of electrical fires due to shorts or arching.

Electrical codes require GFCI devices be used in any wet or damp environment. This includes bathroom receptacles, kitchen areas, crawl spaces, unfinished basements, garages, and almost all outdoor receptacles. If your home does not have GFCI devices already installed, you should consider updating your electrical system to include GFCI protection.

A GFCI protects from electrical shock by constantly monitoring the flow of electrical current through a circuit. The device monitors both the amount of current coming into the device as well as the amount returning to the device. If there is any difference in these amounts it is an indication of a problem and the GFCI will quickly disable the circuit. When the amount of electricity returning to the circuit is lower than the amount going into the circuit, it is often called a 'leak'. This is an indication of a short or other problem somewhere in the circuit.

Many contractors save money by installing a single GFCI device in a required area, then piggy-backing other standard receptacles off the one GFCI. If wiring properly, this does provide the same level of protection as if all the devices were GFCI. A drawback to this method is that it can be very difficult to determine which circuits are protected by GFCI devices when they are wired in this manner. In some instances, the actual GFCI device is located in another room, but provides protection to the kitchen receptacles. To the casual inspector it would appear the kitchen did not have GFCI protection as required by electrical code.

Outlets are not the only type of GFCI protection available for your home. There are GFCI breakers which install at the breaker panel and protect the everything on that breaker line. While this provides a wide coverage, it can have its drawbacks. If there is a short of problem anywhere in the area covered by the breaker the breaker will trip and cannot be reset until the problem is corrected. It can be much harder to trouble shoot a breaker switch than a single outlet, thus repairs can be long and complicated and until they are made the breaker will remain off.

All GFCI devices should be checked monthly to be certain they are working properly. To properly test the GFCI outlet plug a light into the outlet. Then press the 'test' button. The 'reset' button should pop out and the light should go off. If this does not happen the GFCI device is not functioning properly. If the light stays on but the 'reset' button pops out, the device is wired incorrectly. You should contact a certified electrician to make the needed repairs.