WHAT IS A GFCI AND WHY DO I CARE?
A "GFCI" is a ground fault circuit interrupter which monitors the amount of current flowing through an outlet. If there is an imbalance in the electrical flow the GFCI will trip the circuit. This is a device that can prevent over two thirds of the 300 possible electrocutions that occur every year. When you look at a normal 120-volt outlet in the United States, there are two vertical slots and then a round hole centered below them. The left slot is slightly larger than the right. The left slot is called "neutral," the right slot is called "hot" and the hole below them is called "ground." If an appliance is working properly, all electricity that the appliance uses will flow from hot to neutral. If there is an imbalance in the flow from hot to neutral then the GFCI will automatically trip the circuit thereby preventing electrocution.
All GFCIs should be tested once a month to make sure they are working properly and are protecting you from fatal shock. GFCIs should be tested after installation to make sure they are working properly and protecting the circuit.
To test the receptacle GFCI, first plug a nightlight or lamp into the outlet. The light should be on then, press the "TEST" button on the GFCI. The GFCI's "RESET" button should pop out, and the light should go out.
If the "RESET" button pops out but the light does not go out, the GFCI has been improperly wired. Contact an electrician to correct the wiring errors.
If the "RESET" button does not pop out, the GFC1 is defective and should be replaced.
If the GFCI is functioning properly, and the lamp goes out, press the "RESET" button to restore power to the outlet.
TYPE OF GFCIs
Three common types of ground fault circuit interrupters are available for home use:
* RECEPTACLE TYPE
This type of GFCI is used in place of the standard duplex receptacle found throughout the house It fits into the standard outlet box and protects you against "ground faults' whenever an electrical product is plugged into the outlet Most receptacle-type GFCls can be installed so that they also protect other electrical outlets further "downstream" in the branch circuit.
* CIRCUIT BREAKER TYPE
In homes equipped with circuit breakers rather than fuses, a circuit breaker GFCI may be installed in a panel box to give protection to selected circuits The circuit breaker GFCI serves a dual purpose - not only will it shut off electricity in the event of a "ground-fault," but it will also trip when a short circuit or an ov.er-load occurs Protection covers the wiring and each outlet, lighting fixture, heater, etc served by the branch circuit protected by the GFCI in the panel box.
* PORTABLE TYPE
Where permanent GFCls are not practical, portable GFCls may be used. One type contains the GFCI circuitry in a plastic encio-sure with plug blades in the back and receptacle slots in the f rant. It can be plugged into a receptacle, then; the electrical product is plugged into the GFCI. Another type of portable GFCI is an extension cord combined with a GFCI. It adds flexibility in using receptacles that are not protected by GFCls.
WHERE GFCIs SHOULD BE CONSIDERED
In homes built to comply with the National Electrical Code (the Code), GFCI protection is required for most outdoor receptacles (since 1973), bathroom receptacle circuits (since 1975), garage wall outlets (since 1978), kitchen receptacles (since 1987), and all receptacles in crawl spaces and unfinished basements (since 1990).
Owners of homes that do not have GFCls installed in all those critical areas specified in the latest version of the Code should consider having them installed. For broad protection, GFCI circuit breakers may be added in many panels of older homes to replace ordinary circuit breaker. For homes protected by fuses, you are limited to receptacle or portable-type GFCIs and these may be installed in areas of greatest exposure, such as the bathroom, kitchen, basement, garage, and outdoor circuits.
A GFCI should be used whenever operating electrically powered garden equipment (mower, hedge trimmer, edger, etc.). Consumers can obtain similar protection by using GFCIs with electric tools (drills, saws, sanders, etc.) for do-it-yourself work in and around the house.