What is a GFCI?
A ground-fault circuit interrupter (GFCI) is a device that cuts power within milliseconds when it detects current leaking to ground, protecting people from electric shock.
A GFCI compares the current flowing out to the current returning; a small imbalance means current is leaking — often through a person — and it trips. It's required near water: kitchens, bathrooms, garages, outdoors, and similar locations.
GFCIs protect people from shock; AFCIs protect property from arc-fault fires. Many modern circuits use dual-function devices that do both.
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