Blog #13 – Arc-Fault 101

Well.. Its a new month and its time you have heard from us, Arc-Faults Breakers are fairly new and not everyone knows about them. They ARE REQUIRED for any new house, any new Device, and any modification of wiring over 6ft in length.  They cost 8-10 times what normal breakers cost, and the reason is because they are looking for arcs in your wiring. These devices are proven to prevent house fires. If you leave your space heater on and it starts melting the power strip it is plugged into, this type of breaker will trip before it burns your house down. ARC FAULT 101- 2014/2017 Code Not many Electricians know, but its time that you start increasing  your service bids if you don’t want to loose money. 2017 Code, which is enforced in most Maryland Counties, is now in full force and says that anytime you work on any device (changing out receptacles to make them look new) that device must now be ARC Fault Protected! If you are just doing a bathroom or a basement, make sure to add that $45 cost in for the new Arc Fault Breaker. For a new service, pretty much every breaker is now Arc Fault… Smoke Detectors, Dishwashers and more require Arc-Faults, please refer to the National Electrical Code, section 210.12 for a detailed list of where Arc-Faults are required. As of 2017, Arc-Faults are even required in Commercial Buildings; Waiting Rooms, Locker Rooms, Daycare Facilities, Anywhere a little kid can stick something into the socket. There are Single and Double Pole Arc Fault Breakers, Singles Poles cost about half of what Double Pole Breakers Arc-Fault Breakers cost. They are not used very often, but Double Poles Arc-Fault Breakers are needed mostly in older houses where you may have a shared neutral, usually the kitchen small appliance circuits. If you have a situation where you cannot use a Double pole breaker and for some reason the Neutrals are crossed, you can  use 2 Arc Fault Receptacles after the split, one for each branch of the circuit. Some Electricians also do not realize that it is possible to have a GFCI Receptacle on an Arc Fault Breaker, using this combination of devices can be cheaper than a dual-function breaker that preforms both types of testing. This is no safety concerns in doing this, the Code allows for different configurations and it mostly depends on costs and accessibility. In a Kitchen, if you trip a GFI, you really do not want to run all the way down to the basement to reset it. It addition, is also possible to have an Arc Fault Breaker on an Ungrounded Circuit (Old BX or Knob and Tube). The Arc-Fault does not test the ground but it will find any surge in current caused by  older wiring. If you are changing out devices with this type of older wiring, those devices still have to satisfy the requirements of NEC 406.4 (D) concerning replacements, you may still need GFCI Protection or grounding depending on what type of device you are replacing.  If you are an Electrician, remember to tell your customers, the reason this Arc Fault requirement is so harsh is to prevent fires, if you have bad wiring or splices in your home, these breakers will trip before a fire breaks out. I do realize that it can be confusing, but remember, an Arc-Fault tests for surges of electricity between wiring. That surge is sometimes visible, like if you have a vacuum cleaner running and you pull the cord out and see that blue flash, THAT is an ARC of electricity. In Older houses these types of arcs can be small and inside your wall. If you moved into a newly renovated house, and the flipper who did the renovation didnt pull permits and used his carpenter to do his electrical work, you could have this type of arc inside the newly installed junction boxes. I have seen melted receptacles, and melted/twisted boxes in ceilings from installs like this, its no joke.. ALWAYS HIRE LICENSED CONTRACTORS! As for the difference between Arc-Faults and Ground Faults, The breakers and Receptacles DO look similar. However, they preform entirely different tests. A ground fault is looking for a sudden short in the circuit. That short can be between the Power Wire and Neutral, or Power wire and Ground. Like when something gets wet and the water carries the current next to your sink or bathtub. That Live Water is there, just waiting for a path to ground and if you touch it, you become that path. GFI Devices were designed to trip fast enough to save your life. Normal Breakers are NOT designed for this, they trip to protect property, not your life. Recap- Arc-Faults test for a surge of electricity, Ground Faults are looking for shorts in a circuit. Sometimes they are BOTH required in the same circuit. Types of Arc Fault Breakers- (Color is the Test Button) This applies for Square D and Eaton. Siemens have their own colors. Blue – 1st Generation – those are recalled! DO NOT USE Green – 2nd Generation type – they test only in one mode, either Series or Parallel, not both. If you use one of these, you MUST have the first ARC Fault Receptacle in line, not more than 50 CONTINUOUS FEET (no splices) from the panel that is testing for the other condition. They work in conjunction. Yellow – 3rd Generation – This type of Arc-Fault can only test in 1 Mode, Either Series OR Parallel. You MUST use another device, usually an Arc-Fault Receptacle, in conjunction with this breaker to test the opposite condition to satisfy the requirements of the code. White – 3rd Generation – Standard Combination Arc Fault Breaker, these will be the main go to Breaker and they cost about $42, about $5 more than the greens. Purple – also 3rd Generation – Dual Function Breaker, (type DF) this Breaker is GFCI/ARC Fault and is what is required for the Dishwasher/Garbage Disposal Circuit where the devices are hardwired but also located in the Kitchen. ($46 per one) SqD has come out with a new style QO and Homeline Panels that have a Plug-In Neutral Rails. These Rails are what the back of the breaker clips too. It saves a lot of time and makes your jobs look that much better because it eliminates the Pig Tails on the rear of these Breakers. Arc-Faults are fairly complex in their design, they have a circuit board INSIDE the breaker that preforms all the necessary functions.. An Arc-fault Device is supposed to be able to selectively distinguish between a harmless arc that is incidental to the normal operation of switches and plugs, versus a potentially dangerous arc that can occur, such as in a lamp cord with a broken conductor. Despite the fact that Arc-Fault Breakers were introduced and written into electrical codes in the late 1990s (more on this later), several myths still surround Arc-Faults —myths often believed by homeowners, state legislators, building commissions, and even some electricians. “The Following Myths are copied from and corrected as need be from the Electrical Contractors Article discussing such Myths” –

MYTH 1: AFCIs are not important when it comes to saving lives

“AFCIs are very important safety devices that have been proven time and again,” said Ashley Bryant, senior product manager for Siemens. In fact, according to Bryant, includes several success stories on how these breakers have found some very dangerous situations and saved people and property. Arc faults are one of the leading causes of residential electrical fires. Through the 1990s, according to the U.S. Consumer Product Safety Commission (CPSC), an average of over 40,000 fires a year were attributed to home electrical wiring, resulting in over 350 deaths and over 1,400 injuries. The CPSC also reported that over 50 percent of these fires could have been prevented with the use of AFCIs. “The website also includes a UL report noting that the average time to get out of a house in the event of a fire was 17 minutes,” she said. “These days, though, because of homes being larger, having more open floor plans and fewer drywall barriers, and furniture that catches fire easier, that is now down to three minutes.” In addition, the CPSC reports that electrical fires due to arcing tend to occur behind walls, making them more dangerous. That is, these fires can spread undetected more quickly, they can cause more damage than other fires, and they end up being twice as deadly as fires not occurring behind walls, since homeowners tend not be aware of the fires behind walls until it may be too late to escape.

MYTH 2: AFCI manufacturers are driving expanded code requirements for the installation of AFCI

“I find this myth common when I am talking with legislators, but it is important that the electrical industry understand the reality as well when they are talking with their state senators and building commissions,” said Alan Manche, vice president, external affairs, for Schneider Electric. The drive for the expanding code requirements are coming from third-party research. “The Consumer Product Safety Commission and studies conducted by UL with regard to thousands of fires occurring in homes in late 1980s and early 1990s drove the need to address the causes of these fires,” Manche said. “Arc fault protection became the solution that was recognized by the CPSC, UL, and others.”

MYTH 3: AFCIs are only required by codes in a small number of rooms in residential homes

“The National Electrical Code has been expanding the reach of AFCIs beyond residential homes,” said Jim Phillips, P.E. president of, and a contributing editor to ELECTRICAL CONTRACTOR magazine. The first National Electrical Code (NEC) requirement for AFCIs was released in 1999, requiring them to be installed to protect the circuits feeding bedrooms in new homes. In 2008, and again in 2014, the NEC was expanded to require AFCIs to be installed on circuits to more and more rooms in homes, now covering virtually all rooms—bedrooms, family rooms, dining rooms, living rooms, sunrooms, kitchens, dens, home offices, hallways, recreation rooms, laundry rooms, and even closets. In addition, in 2017, the NEC also began requiring the use of AFCIs in college dormitories. It has also expanded requirements to include hotel/motel rooms that offer permanent provisions for cooking.

MYTH 4: An AFCI only protects what is plugged into the specific defective outlet that triggers the electric arc

“An AFCI actually protects the entire circuit,” said Rich Korthauer, vice president, final distribution business, for Schneider Electric. “This includes the electrical panel; the downstream wires that run through the walls; the outlets; the switches; all of the connections to those wires, outlets and switches; and anything that is plugged into any of those outlets and connected to switches on that circuit.”

MYTH 5: A standard circuit breaker will provide just as much protection as an AFCI

Conventional circuit breakers only respond to overloads and short circuits. They do not protect against arcing conditions that produce erratic and often reduced current. “A standard circuit breaker protects the insulation on a wire from an overload,” Korthauer said. “It is not intended to identify bad arcs on circuits in the home. Of course, if you have a dead short, a standard circuit breaker is designed to trip and interrupt that condition.”

MYTH 6: Most AFCI “trips” are the result of “nuisance tripping”

“I hear this myth a lot,” Siemens’ Bryant said. “People believe that certain arc fault breakers are defective because they frequently trip. People need to think of these not as ‘nuisance tripping,’ but rather as ‘safety alerts.’ The majority of the time, these breakers trip because they are supposed to. They are tripping due to some type of arcing event on the circuit.” This can especially be true with “stab” receptacles, where wires are spring-loaded into the backs of the receptacles, instead of wiring around screws, which provide firm connections. In many instances, according to Bryant, when homeowners jam plugs into spring-loaded receptacles or pull them out roughly, it jostles the receptacles, allowing the wires to come loose, which will cause the arc fault breakers to trip. “Again, this is not ‘nuisance tripping,” she said. “It is a ‘safety alert.'” Now, my Official Response to this nuisance Trip is that it is REAL – AFCI’s are supposed to detect arcs, but in fact they only detect “arc-like” electrical waveform patterns, which are produced by MANY common electronic products. Numerous research studies have found that AFCI’s trip incorrectly by misinterpreting noise on the AC line from flat-screen TV’s, wifi routers, powerline network devices, and motors. An incorrect trip is not a “nuisance” it is a product defect which itself can cause injury and economic impact. Each generation of Arc-Faults have gotten better with their design, however they is still not a full-proof device. Enough for today!

Leave a Comment

Your email address will not be published.

Scroll to Top
Scroll to Top