What is GFCI?

May 24, 2024

The electrical systems in modern Seattle, WA, homes have many advantages over those in older ones. That’s because technological advances have made those systems safer and more resilient against failure. One of the most important technologies that sets them apart is GFCI. You’ll often find GFCI outlets installed in kitchens and bathrooms. You may even find them built into the circuit breakers in newer homes. However, even if you’re aware of GFCI, you may not know exactly what it is. Here’s everything you need to know about GFCI, including what it is, how it works, and why it’s important.

What Is GFCI?

GFCI stands for ground fault circuit interrupter. A ground fault is a technical term that describes a current leak from a closed electrical circuit. Under normal circumstances, electricity in your home’s wires travels through a closed loop. For example, an outlet typically contains three wires. There’s a hot wire, a neutral wire, and a ground wire. The hot wire is the wire that carries incoming electrical current into the outlet. The neutral wire carries the current back to your electrical panel, completing the circuit. The ground wire offers a safe path for electricity to flow in the event of a short circuit.

When you plug an electrical device into an outlet, it extends the circuit. It takes the incoming current from the hot wire and returns it to the neutral wire after it passes through the device. However, if something goes wrong with the device, it may pass current through its case or metal parts. In that situation, you’d get a nasty shock if you touched the plugged-in device. The same might happen if the outlet itself got wet and you touched it. In those situations, your body would become a conductor, and the current would pass through it instead of the outlet.

GFCI technology can detect tiny fluctuations in the flow of electrical current through a circuit. When it does, it can trigger a disconnect of the circuit to prevent electrocution. That’s why it’s common to see GFCI outlets installed in parts of homes where there’s water present. You may even see GFCI technology built into the circuit breakers protecting kitchens and bathrooms.

How Does GFCI Work?

GFCI outlets and circuit breakers both contain circuitry that allows them to precisely measure electrical voltage. They measure the voltage coming in via the hot wire and compare it to the voltage leaving via the neutral wire. The moment there’s a difference between the two values, they activate a built-in circuit breaker. Most GFCI outlets and circuit breakers take less than one-tenth of a second to detect a voltage shift and react. While that could be enough time for you to get a shock, you likely wouldn’t suffer any serious injury.

Most GFCI outlets also contain another handy function. They can serve as protection for additional ordinary downstream outlets. To do this, a GFCI outlet features two sets of terminals on its back. One is labeled line, and the other load. This allows you to install a GFCI outlet as the first outlet in a chain. To do this, the incoming hot and neutral wires from the electrical panel connect to the line side. Then, the outgoing hot and neutral wires that run to additional outlets connect to the load side. That places the GFCI circuitry between those other outlets and the main electrical panel. So, if there’s any current leaking from any of those outlets, the GFCI will still detect it and react.

GFCI outlets feature buttons on their faces that allow you to control their functionality. Most will feature a red test button and a black reset button. The test button allows you to simulate a current leak to make sure the GFCI outlet works properly. The reset button sets the outlet back to normal after it trips. The buttons add significant convenience since they let you reset your circuit without needing a trip to your electrical panel.

Where Do You Need GFCI Protection?

In all newly constructed homes, you’ll find GFCI protection on outlets and circuits that pass near water. This may include kitchens, bathrooms, laundry rooms, and basements. There are specific requirements for GFCI outlets laid out in the National Electric Code (NEC). They include:

  • GFCI outlets to serve kitchen countertops
  • GFCI outlets for exterior electrical service
  • GFCI outlets within six feet of sinks, washers, and water heaters
  • GFCI outlets in garages and unfinished basements
  • GFCI outlets within six feet of wet bars

Of course, the NEC only applies to new construction, so it doesn’t mandate adding GFCI outlets to older homes. However, the NEC represents the latest in electrical safety guidelines. So, it isn’t a bad idea to retrofit your home to meet the current NEC standards. It is also typically easy to do this. Our electricians can determine the easiest way to add GFCI protection to circuits in your home. They can trace the outlet wiring in your kitchen and bathroom to see if a single GFCI outlet will do. If not, they can let you know if your electrical panel supports breakers that have GFCI protection.

You should also know that GFCI outlets offer a convenient way to safely replace older, ungrounded outlets. Although ideally, you would want to rewire any parts of your home that lack grounding, that can be costly. Using GFCI outlets and circuit breakers can make those older outlets safer and allow you to plug in three-pronged plugs. However, GFCI outlets won’t improve anything about the safety of your home’s old wiring. For that, you may also wish to install arc fault circuit interrupter (AFCI) circuit breakers. Those can detect damage to your in-wall wiring and cut power to prevent fires.

Your Trusted Local Electrician

Since 1997, Brennan Electric has been the go-to electrician that Seattle residents trust. We offer a complete array of residential electrical services, including electrical panel replacements, repairs, EV chargers, lighting installation, and more. We also install standby and portable generators to protect your home from power outages. We install smoke and carbon monoxide detectors as well to improve your home’s safety. Our team of experienced electricians can handle any electrical job you need done, and we’ll take care of it efficiently, professionally, and with great care to your property. We’ve won the Angi Super Service award for 13 years in a row, which is a testament to our exemplary work. We’re also Better Business Bureau accredited with an A+ rating, and as a member of the community, we have an ongoing partnership with Northwest Harvest. That partnership has already yielded 179,600 meals for needy people and families throughout the state. We even offer financing options on approved credit to help you afford the electrical upgrades your home needs.

If you’d like to add GFCI protection to your home’s outlets or circuits, call the experts at Brennan Electric today, and we’ll take care of it for you.

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