Two kinds of protection show up in almost every modern electrical code, and they are often confused. Both can shut off power in a fraction of a second. They simply guard against different dangers.
A GFCI, or ground fault circuit interrupter, protects people from shock. It compares the current leaving on the hot wire with the current returning on the neutral. If even a tiny amount goes missing, it assumes that current is flowing somewhere it should not, possibly through a person, and it trips. That is why GFCI protection is required near water: kitchens, bathrooms, laundry areas, garages, unfinished basements and outdoor outlets.
An AFCI, or arc fault circuit interrupter, protects the house from fire. It watches a circuit for the erratic electrical signature of an arc, the kind caused by a nail through a cable, a frayed cord behind a couch, or a loose connection inside a wall. An arc can heat the material around it long before a standard breaker reacts. Current code calls for AFCI protection on most living-area circuits, including bedrooms, living rooms and hallways.
A few practical points
- GFCI protection can come from an outlet or a breaker, and the test button should be pressed monthly
- AFCI protection usually lives in the panel as a special breaker
- Combination devices provide both
- Older homes do not have to add them everywhere, but adding them where the risk is highest is one of the most cost-effective safety upgrades there is
If a GFCI outlet keeps tripping, or you are not sure whether your bedrooms have arc fault protection, Northgate Electric can test your circuits and show you exactly where protection is missing. Call (720) 555-0142.
