How GFCI Works

GFCIs (ground fault circuit interrupters) were developed to protect people from electrical shock and fire hazards. The Consumer Product Safety Commission states that if more homes utilized GFCIs, two-thirds of the electrical shocks experienced in homes could be avoided.

Why GFCIs?

• A ground fault occurs when there is a leak of electrical current into the ground. If a person were to provide a path to the ground for the leak, he could be severely burned or electrocuted. A GFCI detects this leakage of power and shuts the current off, thus protecting people from injury.

How it Works

• GFCIs continuously monitor the electricity in the circuit to detect any loss of current. If the current that flows through the circuit ever differs from the amount of current returning, the GFCI quickly shuts off the electricity to the circuit. This happens in as little as 1/40th of a second, preventing anyone from receiving a fatal dose of electricity.

Types

• There are three different kind of GFCIs for home use. A receptacle type fits into standard electrical receptacles and also prevents other non-GFCI outlets further down the circuit. A circuit breaker type can be installed in a home's panel box to protect selected circuits. A portable GFCI plugs into any electrical receptacle and then the electrical appliance is plugged into the GFCI, affording protection where a permanent GFCI would not be practical.