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AFCI vs GFCI – What Are the Major Differences?

Written by Edwin Jones / Fact checked by Andrew Wright

afci vs gfci

Breakers are vital because they play a significant part in preventing electrical accidents from occurring in our homes.

Two of the common types of circuit breakers are AFCIs and GFCIs. Homeowners may not know when to use which of these. However, they both are crucial in terms of safeguarding our electrical system.

That is why I wrote this guide on the distinction between AFCI vs GFCI. In short, the former guards against arc faults, while the latter is for ground faults. If you want to know more about the difference between AFCI and GFCI, then read through my article.

What Are AFCIs and GFCIs

AFCI

afci-outlet-vs-gfci

First, let me explain what AFCI stands for and the basic premise of its protection.

AFCIs stand for Arc Fault Circuit Interrupter. True to its name, this type of breaker specifically prevents arc faults from happening in our electrical circuits.

In case you have no idea what an arc fault is, let me visualize it for you. According to electricians, an arc fault is caused by electrical discharges from two or more conductors that have “leaks” due to their faulty insulators.

If left unattended, arc faults are dangerous enough to start electrical fires, and even injure or electrocute people that are caught within their vicinity. This is why a safety instrument like AFCI is important in keeping homes with arc fault protected.

Due to the recognized danger of arc faulting, the 2014 National Electrical Code (NEC) required the installation of AFCI breakers in all properties.

In particular, it demands the following:

  • AFCIs are to be installed in 15A and 20A dwelling area branch circuits;
  • Hotel and motel rooms are likewise required to install AFCIs based on the above requirement;
  • Most importantly, ACFIs must be within reach and accessible.

GFCI

arc-fault-protected

Now that we have discussed what AFCIs are, let us turn to ground fault circuit interrupters, more commonly abbreviated as GFCIs.

A ground fault circuit interrupter is a safety device that is used to protect against electrical accidents. It is typically used in areas where there is moisture, such as in bathrooms or near swimming pools.

Ground faults, the type of electrical discharge that is regulated by GFCIs, is the accidental creation of an electrical route connecting a power source and a surface intended to be grounded.

Leakage of electrical discharges caused by incorrect grounding or water touching outlets can incapacitate or even kill people.

Understanding the risk of an electrical ground fault, the NEC likewise provided general guidelines regarding the installation of ground fault circuit interrupters.

Particularly, the NEC outlined the following requirements for home spaces:

  • GFCIs must be installed in circuits near pools.
  • Ground fault circuit interrupters are to be installed in 15A, 20A, and 125V receptacles in bathrooms, garages, storage areas, and kitchens.

How Do AFCIs and GFCIs Work?

arc-fault-circuit-interrupter

AFCI

Now that we have discussed what arc fault circuit interrupters do, let’s move on to knowing how they work. Now, this type of breaker can recognize the following arc fault types which, when detected, trigger it to shut the flow of electricity.

  • Loose Connections

Loose wire connections can inadvertently cause arc faulting as electricity flowing them can leak and interact with adjacent cables.

Some electrical components that could cause arc faulting when connected loosely and incorrectly are: breaker box terminals, appliance connections, and circuits running through the walls of your home.

  • Overheated Wires

The capacity of wires to maintain their insulation is vastly dependent on internal and external factors. For instance, factors such as the wire’s surrounding environment and gauge must be taken into consideration. Undersized cables tend to get hot, for instance.

In addition, wires that conduct electricity of a higher load would create more heat compared to those that carry less power. It is in this regard that electrical wires carrying higher electrical demands are at the most risk of overheating.

Such wires could sometimes melt due to the tremendous heat they’re under. The melting of the insulation could then create gaps wherein arc faults could happen.

  • Corroded Terminals

Besides the aforementioned reasons, arc faults can also occur at terminals that act as the termination point of circuit wires. These terminals, when exposed to water, may experience corrosion, which leads to contact resistance and arc faulting.

GFCI

As we have discussed above, GFCIs are solely focused on detecting ground faults. Now, ground fault circuit interrupters do this by shutting off electricity whenever it flows somewhere it’s not meant to flow.

They do this by calculating the amount of current that is supposed to course through a circuit.

When they detect any difference between actual vs expected current, GFCIs trip their internal switch, temporarily stopping the flow of electricity in the faulty circuit.

What is the Difference Between AFCI and GFCI Breakers?

arc-fault-vs-ground-fault

Now that we have discussed the particulars of arc fault vs ground fault, AFCI vs GFCI receptacle, where are AFCI and GFCI required, let us turn our attention to their differences.

Essentially, AFCI protects against arc faults, while GFCI protects against ground faults. Thus, the former targets electrical problems that occur inside walls, while the latter often deals with issues that happen externally within properties.

In terms of whether to install an AFCI or GFCI in kitchen, the NEC requires both of them in said room.

Can I use AFCI instead of GFCI? The answer depends on the type of protection you want. Think of the faults they protect against and where you’re installing the breaker, as the two are not interchangeable.

In some cases, you will have to use both, such as when installing 15A branch circuits in bathrooms.

Conveniently, manufacturers now make dual function AFCI/GFCI receptacle, granting homeowners protection against arc and ground faulting without the need to install two different safety instruments.

GFCI vs AFCI: Which is Better? Pros and Cons of Both

difference-between-afci-and-gfci

Given the distinction between AFCI outlet vs GFCI outlets, there are specific areas where both excel and are weak in.

GFCI AFCI
  • Provides protection against ground fault
  • Prevents electric shocks and electrocution
  • Has partial arc fault protection, as long as the fault concerns grounding
  • Offers parallel arc protection
  • No ground fault protection
  • Stops electrical fires due to arc faulting from happening

Aside from the above, a notable breaker that should be included in our discussion would be CAFCIs or Combination Arc Fault Circuit Interrupter. CAFCIs are like AFCIs, in the sense that they are upgraded versions of the latter and capable of series arc protection.

That being said, when comparing CAFCI vs GFCI, you will still have to use GFCIs for ground fault.

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Conclusion

Being informed about the different types of breakers is vital for homeowners who want to secure their homes against electrical fires and other accidents.

In this regard, knowing the difference between AFCI vs GFCI is helpful for people who want to install the proper breakers for their homes.

I can only hope that I have shed light on the differences between the two. That being said, if you have any questions, don’t hesitate to let us know. Thanks for reading!

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