What are Arc-Faults and Why are They Dangerous?

By Scott Bowers,

Leviton Electrical Fire Infographic

An arc-fault is an unintentional arcing condition in a circuit. Arcing creates high intensity heating at the point of the arc, resulting in burning particles that can exceed 10,000 degrees Fahrenheit and may over time ignite surrounding material such as wood framing or insulation. 

There are two types of potentially dangerous arcs – parallel arcs and series arcs. 

Source: Leviton

What Causes Arc-Faults?

Often unseen, arc faults can occur anywhere in the home’s electrical system including:

Within Walls

  • Within walls from nails, screws or staples inadvertently driven into wires.

Within Cords

  • Within electrical cords accidently damaged by furniture resting or pressing upon them.

Within Loose Connections

  • At loose electrical connections or cords damaged by doors closing on them.

Within Damaged Cords

  • Through old or cracked wires or cords as well as wires or cords damaged by heat, sunlight or humidity. 

Prevention and Consequences of Electrical Fires

Source: Leviton

AFCI, GFCI, and AFGF Residential Breakers

By Scott Bowers,


What’s the Difference Between BR and CH Breakers?


  • BR breakers are 1″ in Width.
  • BR breakers are black, with black handles (In most cases. Some older styles have multicolored handles.)
  • BR breakers carry a 10 Year Warranty.


  • CH breakers are 3/4″ in Width.
  • CH breakers are Black with Sandalwood (Tan) handles.
  • CH breakers carry a lifetime warranty.

What’s the Difference Between Type 1 and Type 2 Surge Protective Devices?

  1. Type 1 devices are installed before the main device in the loadcenter, whereas Type 2 are installed following the main devices in the loadcenters. As stated in the catalog: “Type 1 Surge Protective Device (SPD)s are intended for installation between the secondary of the service transformer and the line side of the service equipment overcurrent device, as well as the load side, including watt-hour meter socket enclosures, and are intended to be installed without an external overcurrent protective device. Type 1 devices are dual-rated for Type 2 applications as well, providing the highest ratings available for installation at the service entrance.
  2. Type 2 Surge Protective Device—Permanently connected Type 2 SPDs are intended for installation on the load side of the service equipment overcurrent device, including SPDs located at the branch panel.” the Eaton Surge website

Residential Breakers Color Matrix

Source: Eaton.com


By Scott Bowers,

While AFCI debates continue, more can be done to increase safety by broadening their use

(Article originally published on Eaton.com and features the opinions of Thomas Domitrovich, P.E., LEED AP, vice president, technical sales.)

AFCI (Arc Fault Circuit Interrupter) protection is essential to reducing the likelihood of electrical fires and the primary reason the National Electrical Code (NEC) first sought to provide this protection in new homes in 1999. The NEC 2020 code cycle continues the journey of AFCI protection for all 15- and 20-amp branch circuits. In my opinion, while the expanded requirements will significantly increase safety, some in the industry seek to impede this code advancement as they believe the code does little to affect fire dangers associated with arcing conductors.

The great AFCI debate: four points to consider

AFCIs were created to detect conductor arcing and sparking that can cause fires. By shutting power off to damaged circuits, the devices reduce the likelihood of electrical fires in new and existing homes, dormitory units, guest rooms and suites. As with many new technologies in our industry, debate ensues, with individuals and sometimes organizations speaking against these installation requirements. Four points are at the crux of the debate: cost, unwanted tripping, technological advancement and the impact of fire statistics.

Point 1: Cost to the housing market

Some in the industry claim that any cost increase of a dwelling will prevent potential home buyers from making purchases. Financials can be greatly exaggerated to the point of absurdity. I’ve been a part of discussions, for example, where it was claimed that AFCI devices add $4,000 to the price of a 1,500 square-foot home. In reality, the cost is around $200. Considering that a home is often the most substantial investment people make in their lifetime, the cost of an AFCI device is pennies a month when rolled into a 30-year mortgage. In short, AFCI costs pale in comparison to ensuring a safer home.

I’ve been a part of discussions, for example, where it was claimed that AFCI devices add $4,000 to the price of a 1,500 square-foot home. In reality, the cost is around $200.

Thomas Domitrovich, P.E.

Point 2: Unwanted tripping of devices

AFCI technology has been on the market for well over a decade. And, like Ground Fault Circuit Interrupter (GFCI) technology, it’s unforgiving in detecting circuit problems. Many times when an AFCI or GFCI detects a problem, we mistakenly blame the device without realizing it’s just doing its job.

In my opinion, AFCI technology took a path of acceptance similar to the GFCIs brought to market in the 1970s. GFCIs saw compatibility issues due to installation practices and because general appliances permitted high levels of leakage current that tripped GFCI-protected circuits. Over time, the industry changed by updating and communicating installation practices and, in some cases, worked with manufacturers to reduce products’ leakage current. One could argue that the introduction of GFCIs significantly improved installation practices and also appliance manufacturing and construction.

Similar to GFCIs, AFCIs saw challenges with connected loads and installation practices when first introduced, but over the past 15+ years significant improvements have been made. I believe today’s AFCI technology is highly dependable and, with that, the tripping of AFCI safety devices must not be ignored. Contractors in the field should work to understand why a trip occurs. Today’s advancements in both AFCI and GFCI technologies are such that tripping issues, although sometimes difficult to resolve, are likely not due to incompatibilities but rather to problems that must be addressed.

Point 3: Technological advancement is a constant

As more solutions enter the market featuring the level of protection the NEC seeks, manufacturers of any one technology may feel their solution use is threatened. The NEC is providing more options than ever to provide protection for both new and existing homes. These new technologies are customer options and will impact the consumer buying decision. Though new technologies may impact the sale of some products, manufacturers should refrain from impeding the progress of safety.

GFCI receptacle manufacturers and sellers are naturally concerned about the threat to their businesses. While no one wants to see businesses struggle, I believe competition is a catalyst for better solutions. The current requirements of the NEC provide protection of the entire branch circuit. In my opinion, there’s no reason to reduce the level of protection — especially for the sake of the sale. As technology progresses, it is quite possible that new ways of providing protection could require innovation in GFCI technologies to stay competitive. I firmly believe we should not acquiesce for financial gain.

There’s no reason to reduce the level of protection — especially for the sake of the sale.

Thomas Domitrovich, P.E.

Point 4: Fire statistics are misleading

Some call for the removal of the AFCI requirement altogether, arguing that there hasn’t been a significant impact to fire statistics since AFCIs came on the market in the early 2000s.

This claim is correct on its surface. Fire statistics haven’t changed much, but for a good reason. Most of today’s homes were built before the NEC required AFCIs in 2002, which only stipulated bedroom-circuit protection at that time. Add to that the slow expansion progress of AFCI protection: in 2001, the NEC called for an average of two circuit breakers in new homes; in 2014, only a handful more was added.

In short, fire statistics can be misleading because we don’t have a sample size large enough to affect the numbers in either direction. It’s going to take time to increase the number of AFCIs installed to impact statistical relevance. Over time, as older homes are demolished or updated to meet new code requirements, we should begin to see a change in the numbers.

Contractors and homeowners should make changes now

Overall, I believe we’re heading in the right direction for new home construction. As with any electrical technology, change is a slow process. It’s up to us all to understand the safety benefits of AFCIs and do more to increase safety. That starts with fact-based, honest conversations about NEC requirements.

I encourage all contractors and homeowners to consider going above and beyond the bare minimum requirements of the NEC and to look at installing AFCI technology in existing homes. Doing so will increase safety and will positively impact the industry thanks to additional information garnered from the entire housing inventory.

(SOURCE: Eaton. No copyright infringement intended)

What is an AFCI? (Arc-Fault Circuit Interrupter)

By Scott Bowers,

Starting January 1, 2002, The National Electrical Code , Section 210-12, required that all branch circuits supplying 125V, single phase, 15 and 20 ampere outlets installed in dwelling unit bedrooms be protected by an arc-fault Circuit interrupter. Eventually there were more areas that were required, but the NEC selected to require them on bedroom circuits first because a CPSC study showed many home fire deaths were related to bedroom circuits.

The AFCI (Arc Fault Circuit Interrupter) breaker, will shut off a circuit in a fraction of a second if arcing develops. The current inside of an arc is not always high enough to trip a regular breaker. You must have noticed a cut or worn piece of a cord or a loose connection in a junction box or receptacle arcing and burnt without tripping the regular breaker. As you can guess this is a major cause of fires in a dwelling.

There is a difference between AFCIs and GFCIs. AFCIs are intended to reduce the likelihood of fire caused by electrical arcing faults; whereas, GFCIs are personnel protection intended to reduce the likelihood of electric shock hazard. Don’t misunderstand, GFCIs are still needed and save a lot of lives.
Combination devices that include both AFCI and GFCI protection in one unit will become available soon. AFCIs can be installed in any 15 or 20 ampere branch circuit in homes today and are currently available as circuit breakers with built-in AFCI features. In the near future, other types of devices with AFCI protection will be available.

Main Street Electric Company are proud users of Eaton products. Watch Erik Drost at Eaton’s Power Systems Experience Center in Pittsburgh, Pennsylvania where he discussed Arc Fault Circuit Interrupter (AFCI) technology and how it helps keep your home safe.

How an AFCI works and why every home should have them installed.

If a GFCI receptacle is installed on the load side of an AFCI it is possible for both the AFCI and the GFCI to trip on a fault if the current exceeds the limit for both devices. It is also possible for the AFCI to trip and the GFCI to not trip since the two devices could race each other. However, in no case is safety compromised.

At first the cost for AFCI was high. End-users pai between $20 and $50 for each AFCI. The cost is expected to dropped as much more are ordered.

Code Section 210-12

(a) Definition: An arc-fault circuit interrupter is a device intended to provide protection from the effects of arc faults by recognizing characteristics unique to arcing and by functioning to de-energize the circuit when an arc fault is detected.

(b) Dwelling Unit Bedrooms. All branch circuits that supply 125-volt, single-phase, 15- and 20-ampere receptacle outlets installed in dwelling unit bedrooms shall be protected by an arc-fault circuit interrupter(s). This requirement shall become effective November 1, 2002.

There are a lot of homes that have been wired with aluminum wiring and it would not be financially possible to rewire the entire house or service.

There are a few things you can do to make sure that the wiring is not becoming a problem:

  • You should be on the lookout for devices or lighting going on and off.
  • Breakers or outlets overheating. Have the main panel checked for corrosion or loose connections.
  • When adding copper devices or wire to aluminum, make sure this work is done by someone who knows the proper procedure for this type of wiring.
  • A little preventative maintenance can go a long way in preventing future safety hazards.

Read more about the “AFCI Debate” in another one of our blog posts here.