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ELECTRICAL INSPECTION, DIAGNOSIS, REPAIR
ACCURACY vs PRECISION of MEASUREMENTS
AFCIs ARC FAULT CIRCUIT INTERRUPTERS
ALUMINUM SECs & WIRING
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AMPS & VOLTS DETERMINATION
AMPACITY - the LIMITING FACTOR
APPLIANCE EFFICIENCY RATINGS
BACKUP ELECTRICAL GENERATORS
BACK-WIRED ELECTRICAL DEVICES
BOOKSTORE - ELECTRICAL
BUILDING SAFETY HAZARDS GUIDE
Cadet & Encore Heater Recall
CIRCUIT BREAKER FAILURE
CIRCUIT BREAKER SIZE for A/C or HEAT PUMP
Classified CIRCUIT BREAKER WARNING
CORROSION in ELECTRICAL PANELS
CORROSION & MOISTURE SOURCES in PANELS
CUTLER HAMMER PANEL FIRE
DEFINITIONS of ELECTRICAL TERMS
DIRECTORY OF ELECTRICIANS
DMM Digital Multimeter HOW TO USE
ELECTRIC METERS & METER BASES
ELECTRIC MOTOR DIAGNOSTIC GUIDE
ELECTRIC MOTOR OVERLOAD RESET SWITCH
ELECTRIC PANEL AMPACITY
ELECTRIC PANEL INSPECTION
ELECTRIC PANEL MOISTURE
Electric Power Frequency Table
ELECTRICAL DISTRIBUTION PANELS
ELECTRICAL GROUND SYSTEM INSPECTION
ELECTRICAL SERVICE DROP
ELECTRICAL SERVICE ENTRY WIRING
EMF RF FIELD & FREQUENCY DEFINITIONS
FEDERAL PACIFIC FPE HAZARDS
FIRE SAFETY Checklist, CPSC
GFCI PROTECTION,Testing GFCIs AFCIs
HEATING COST FUEL & BTU Cost Table
HEAT TAPE USAGE GUIDE
Hertz - Definitions of KHz MHz GHz THz
KNOB & TUBE WIRING
LIGHTING, EXTERIOR GUIDE
LIGHTING, INTERIOR GUIDE
LIGHTNING PROTECTION SYSTEMS
LOW VOLTAGE BUILDING WIRING
LOW VOLTAGE TRANSFORMER TEST
MAIN ELECTRICAL DISCONNECT
MAIN DISCONNECT AMPACITY
MOISTURE SOURCES in PANELS
MURRAY SIEMENS Recall
PHOTOVOLTAIC POWER SYSTEMS
PUSHMATIC - BULLDOG PANELS
REMOTE ELECTRIC POWER, PHOTOVOLTAIC
RUST in ELECTRICAL PANELS
SAFETY for ELECTRICAL INSPECTORS
SE CABLE SIZES vs AMPS
SIEMENS MURRAY Recall
UNDERGROUND SERVICE LATERALS
VOLTS / AMPS MEASUREMENT EQUIP
VOLTAGE MEASUREMENT METHODS
WIND ENERGY SYSTEMS
WIND TURBINES & LIGHTNING
ZINSCO SYLVANIA ELECTRICAL PANELS
Arc Fault Circuit Interrupt or Information: this article, adapted and expanded from a US CPSC article on AFCIs is supplemented with additional details and commentary answers most home owner and home inspector questions about installing, testing, and inspecting AFCIs - arc fault protectors in homes.
Page top photo courtesy of the US CPSC.
Green links show where you are. © Copyright 2014 InspectApedia.com, All Rights Reserved.
This material was originally prepared by DF for the American Society of Home Inspectors New England Chapter,( ASHI -NE) Educational Seminar, Sept 22-23, 2008. Portions of this text are quoted from the Arc Fault Circuit Interrupter (AFCI) FACT SHEET provided by the US CPSC .
[Click to enlarge any image]
Additional notes and details have been added, drawing on a variety of sources listed at the end of this article.
Arcing faults: a series arc occurs in electrical wiring when there is a small gap or break in a conductor. a parallel arc occurs when a small gap or break which permits current to flow to ground (a ground fault) or between the hot and neutral wires (a short circuit).
See Arcing Types in this article for more details.
Arcing hazards in electrical systems have long been recognized as a problem and a potential hazard dating at least to the 1920's in the U.S. but devices to protect from arcing faults in the home are much more recent.
Arc fault circuit interrupters: an “AFCI” is an arc fault circuit interrupter first introduced in 1998. AFCIs are designed to protect against fires caused by arcing faults in the home electrical wiring.  What is the actual hazard?
Arcing faults, especially parallel arcing faults, lead to overheating and a fire hazard even if no shock hazard is present. Electrical arcing faults have been described in detail by Shea who explained how electrical arcing faults can be a serious fire hazard and one that is distinct from ground faults intended to be addressed separately by GFCIs.
Also see GFCI PROTECTION,Testing GFCIs AFCIs
Typical wiring details for AFCI circuit breakers
Our AFCI photo at left illustrates a Square-D 20A AFCI breaker during installation in the electrical panel.
The light green arrow points to the AFCI device - you'll notice that it is much longer than conventional circuit breakers in the panel. Each AFCI breaker involves three electrical connections:
Our next AFCI breaker photo shows more closely the electrical circuit connection points at the AFCI breaker itself.
The molded case of the AFCI breaker also indicates which wires should be attached to which terminals, as will instructions included with the device.
Why are AFCI's [Possibly] Important?
AFCIs are an important safety addition to homes in part because they address an additional type of electrical fault that can cause a fire and one which may not be detected and interrupted by a conventional circuit breaker, nor by a ground-fault circuit interrupter (GFCI's).
We've seen that arcing of any type can result in burned debris on wire surfaces which causes an increase in electrical resistance and thus overheating at that point. Arcing was examined earlier in detailed studies of the aluminum electrical wiring fire hazard at connections in the wire. Arcing of any type, whether it is the micro-fretting type of arcing that occurs with aluminum wire or possibly larger arcing across a gap or short in a copper wire.
Annually, over 40,000 fires are attributed
to home electrical wiring. These fires
result in over 350 deaths and over 1,400
When unwanted arcing occurs, it generates high temperatures that can ignite nearby combustibles such as wood, paper, and carpets.
Our photo shows a Rhinebeck NY home that was totally destroyed by a fire caused by an electrical cord that was passed under a carpeting - a possible cause of pinched, overheated cord, and a fire that might have been prevented by an AFCI.
Certainly the circuit involved was in an older home and was not protected by an AFCI (nor by a GFCI as we understood the case). In any event the heater cord did not blow a fuse nor trip a breaker in this home. Instead it just lit the home afire.
InspectAPedia Note: According to Mike Holt, "Studies have shown that over 60 percent of fires are from causes in the fixed wiring, switches, receptacle outlets and lighting fixtures that are part of the fixed electrical system of a residence." In other words, AFCI's are focused on detecting arcing and preventing fires in an area where the risk is significant.
Arcing faults often occur in damaged or deteriorated wires and cords. Some causes of damaged and deteriorated wiring include:
and cord exposure to heat vents and sunlight.
Coffee Maker Demonstrates Early warning about nuisance tripping of AFCI circuit breakers and consumer objections to these devices
Watch out: we have heard several reports of excessive "nuisance" tripping of arc fault circuit interrupters, and our own limited testing has confirmed this problem in our laboratory where we installed the coffee maker shown at left.
On a newly-wired AFCI electrical circuit with tight, well-made connections and powering a string of electrical receptacles, we connected a single device: a Keurig™ coffee maker to the circuit (photo at left). The circuit also supports a wall mounted light that uses florescent bulbs. No other devices were connected to the circuit.
The coffee maker was set to turn itself off automatically after one hour of idle time. Yet consistently over 30 days of testing, every day we observed that the 15-A Square D AFCI for this circuit tripped off at least once.
We suspect that electrical properties of the coffee maker may have been the source of noise on the circuit that was causing the AFCI to switch off. Replacing the AFCI with a conventional 15-A Square D circuit breaker completely eliminated the nuisance tripping on this circuit.
Three other AFCIs were installed in the same electrical panel, but only one was connected to an electrical circuit in active use. On that circuit, also supporting a string of electrical receptacles powering lighting and computer equipment during the same 30-day test period, no nuisance trips of the circuit were observed.
Watch out: as with GFCI's discussed at MULTI-WIRE CIRCUITS, installing AFCIs on multi-wire branch circuits using a shared neutral requires installation of a common trip tie, and nevertheless the circuit and this circuit protection device may be subject to further nuisance trips or unexpected behaviors.
Watch out: An installing electrician informed us that many of his customers were complaining about nuisance tripping and that he was asked by those clients to remove the AFCI devices and to replace them with conventional circuit breakers. This raises an issue about national and local electrical code compliance and about building electrical and fire safety - removing a code-required safety device.
Further testing of the nuisance-tripping AFCIs as well as three others installed in the same electrical panel and samples of non AFCI breakers of the same age, rating, and brand is underway and will be reported here.
Also see APPLIANCE DIAGNOSIS & REPAIR
UL in January 2002 described various types of AFCIs which we summarize here. The first three types of AFCI's, Branch Feeder AFCIs, Outlet Circuit AFCIs, and Combination AFCIs are the three most basic types of arc fault detectors and are important definitions for the home owner or home inspector to understand:
Conventional circuit breakers only respond to overloads and short circuits; so they do not protect against arcing conditions that produce erratic current flow. An AFCI is selective so that normal arcs do not cause it to trip.
The AFCI circuitry continuously monitors current flow through the AFCI. AFCIs use unique current sensing circuitry to discriminate between normal and unwanted arcing conditions. Once an unwanted arcing condition is detected, the control circuitry in the AFCI trips the internal contacts, thus de-energizing the circuit and reducing the potential for a fire to occur.
An AFCI should not trip during normal arcing conditions, which can occur when a switch is opened or a plug is pulled from a receptacle.
Presently, AFCIs are designed into conventional circuit breakers combining traditional overload and short-circuit protection with arc fault protection. AFCI circuit breakers (AFCIs) have a test button and look similar to ground fault circuit interrupter (GFCI) circuit breakers.
Some designs combine GFCI and AFCI protection. Additional AFCI design configurations are anticipated in the near future.
It is important to note that AFCIs are designed to mitigate the effects of arcing faults but cannot eliminate them completely. In some cases, the initial arc may cause ignition prior to detection and circuit interruption by the AFCI.
The AFCI circuit breaker serves a dual purpose – not only will it shut off electricity in the
event of an “arcing fault”, but it will also trip when a short circuit or an overload occurs.
The AFCI circuit breaker provides protection for the branch circuit wiring and limited
protection for power cords and extension cords. Single-pole, 15- and 20- ampere AFCI
When did the NEC Begin Requiring AFCIs & Where should Arc Fault Circuit Interrupters (AFCIs) be used? Are Combination AFCI's effective?
The 1999 edition of the National Electrical Code, the model code for electrical wiring adopted by many local jurisdictions, requires AFCIs for receptacle outlets in bedrooms, effective January 1, 2002. Although the requirement is limited to only certain circuits in new residential construction, AFCIs should be considered for added protection in other circuits and for existing homes as well.
In 2008 the NEC added a requirement for AFCI protection in all living areas and also added that "only combination AFCI's are allowed". 
Older homes with aging and deteriorating wiring
systems can especially benefit from the added protection of AFCIs. AFCIs should also
be considered whenever adding or upgrading a panel box while using existing branch
Watch out: While AFCI-related patents date from as early as 1985, the current and most-widely installed AFCI designs were developed and patented by Joseph C. Engel, Robert T. Elms, & John C. Schlotterer with key patents assigned to Eaton Corporation.
But Dr. Engel has argued that the current devices as marketed do not properly identify and address the types of electrical hazards that were addressed by his original invention. Quoting from Engel (2012) ,
InspectAPedia Notes: What are the code requirements for AFCIs?
AFCI Requirements under the US National Electrical Code NEC:
AFCI requirements have not been adopted uniformly in all jurisdictions, but the requirement is being increasingly accepted, and we certainly recommend the use of AFCIs as described by the US CPSC and the NEC.
The US National Electrical Code, the NEC, specifies the following requirements for AFCIs (quoted indirectly from the U.S. State of Vermont office of the state fire marshal, January 2007. Vermont has required AFCIs to the NEC 2008 standard since 2000.)
History of AFCI Requirements in Homes
The 1999 NEC rules, effective in 2002, in NEC Sec. 210.12. introduced AFCI's and called for their installation on bedroom receptacle circuits powered by single phase 125V(nominal) 15A and 20A circuits.
The 2002 NEC expanded the use of AFCI's to include all bedroom circuits (such as lighting and hard-wired smoke alarms), kitchens.
The 2005 NEC code expanded the section to include combination AFCIs combined with GFCIs, basically an update to reflect improvements in the technology. The technology of AFCIs was improved to add the detection of series arcing to the previously available parallel arcing. By removing the word "receptacle" from the code in 2002, and by leaving the word "outlet" in the code, the 2005 code indicated that all outlets, including receptacles, light fixtures, smoke alarms, etc. must be protected.
The 2008 NEC expanded the use of AFCI's to include all habitable rooms in new homes such as living rooms and dining rooms. The 2008 requirements mean that only only Combination AFCI's will meet all of the requirements of the code. GFCI's (Ground Fault Circuit Interrupters) continue to be required to protect areas of high shock risk: bathrooms, kitchens, garages, un-finished basements.
Combination devices required after 1 Jan 2008: Simplifying a bit, after January 1, 2008, AFCI protection must be provided by a "Combination AFCI's" . That's because these are an improved arc fault interrupter product that offer much more sensitive arc fault detection (5 A arc peaks as opposed to 75 A arc peak detection).
210-12. Arc-Fault Circuit-Interrupter Protection (1999, Effective 2002)
(A) Definition. An arc-fault circuit interrupter is a device intended to provide protection from the effects of arc faults by recognizing the 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 circuits installed in dwelling unit bedrooms shall be protected by an arc-fault circuit interrupter(s). This requirement shall become effective January 1, 2002.
Beginning with the 2008 edition of the U.S. National Electrical Code, AFCI's are required not only in bedrooms but in other areas of the home such as dining rooms, living rooms, and other habitable areas, and apply to most electrical circuits including hard-wired smoke detectors, overhead fans, etc.
An AFCI circuit breaker typically costs about $30. to $35. U.S. A conventional 15A circuit breaker typically costs $2. to $4. There is an additional cost to install an AFCI circuit breaker, but as it's basically a "plug-in" device that is placed in the electrical panel, that number should be small, smaller still if the AFCI installation is combined with other electrical work needed at a home.
While these specialized AFCI circuit breakers cost more, our opinion is that this is not a significant cost compared with the value of a home, not to mention the more difficult to measure cost of possible injuries or fatalities should a fire occur.
If we use the current (2014) median price of a new home in the U.S. of about $260,000., the cost of adding AFCI to a home circuit is less than two ten-thousandths of the cost of the home. (An AFCI costs 0.00016 x median value of a home in the U.S.).
If a home needs a dozen AFCI's to meet the 2008 NEC, the cost should be less than $400., or less than two thousandths of the cost of the home. (0.0019 x the median value of a home in the U.S.).
Nuisance tripping refers to a circuit breaker or an AFCI that trips off, turning off electrical power when there was no apparent reason to do so. Some sources assert that what appears to be "nuisance tripping" of AFCI's actually occurs due to wiring practices of some electricians more than for any other reason. These include
In homes equipped with conventional circuit breakers rather than fuses, an AFCI circuit breaker may be installed in the panel box in place of the conventional circuit breaker to add arc protection to a branch circuit. Homes with fuses are limited to receptacle or portable-type AFCIs, which are expected to be available in the near future, or AFCI circuit breakers can be added in separate panel boxes next to the fuse panel box.
An AFCI hookup wiring diagrams and detailed instructions from GE is available here. Other manufacturer's Arc Fault Interrupter installation guidelines will be similar.
Typically for an electrical circuit to be protected by AFCI, in the electrical panel the circuit hot and neutral wires are connected to marked terminals on the AFCI circuit breaker and a third wire connects the AFCI breaker to the neutral bus in the electrical panel.
The AFCI installation wiring diagram shown here and others are available from GE, General Electric Corporation and GE circuit breaker distributors.
Do not attempt to work on your electrical wiring, switches, or outlets unless you are properly trained and equipped to do so. Electrical components in a building can easily cause an electrical shock, burn, or even death.
Even when a hot line switch is off, one terminal on the switch is still connected to the power source. Before doing any work on the switch, the power source must be turned off by setting a circuit breaker to OFF or removing a fuse.
Using the test button on an AFCI
AFCIs should be tested after installation to make sure they are working properly and protecting the circuit.
Subsequently, AFCIs should be tested once a month to make sure they are working properly and providing protection from fires initiated by arcing faults.
A test button is located on the front of the device. The user should follow the instructions accompanying the device. If the device does not trip when tested, the AFCI is defective and should be replaced.
InspectAPedia Notes: How the AFCI Test Button Functions
Because it has been misunderstood and criticized it's worth noting that the test button on an AFCI does not simply force the mechanical internal switch of the AFCI to trip. Rather, the test button on an AFCI tests the arc fault detection circuitry to be sure that it is working properly, that it will respond to an arc fault, and that the circuitry will in turn cause the mechanical internal switch to open.
This is an important distinction to remember, since the Ground Fault Circuit Interrupter (GFCI) has faced similar criticism. We've certainly found lots of GFCI's which exhibited an error when the GFCI test button was pressed: the button caused the GFCI to trip but the device was defective or improperly wired so that it would not protect the circuit.
Using AFCI indicator tools vs AFCI "test tools" - AFCI Indicators is not recommended
As of September 2008 we have found no test tool that reliably and completely tests the function of an AFCI. Only the integral test button tests the circuitry of the device as well as the trip mechanism. UL classes these "test" devices not as "testers", but as "indicators".
A problem is that some devices used to "inspect" an AFCI, in trying to produce a simulated arc fault condition, may fail to cause the AFCI device to trip even though it is perfectly fine.
Literature from the manufacturer of a popular "test tool" tells the user of the tool to go to the electric panel and use the test button on the AFCI device to make sure it trips. In other words the inspector cannot rely on the separate test tool. For this reason you will see such tools referred to as "indicators" rather than "testers": they are not a complete and reliable test instrument for AFCIs. -- Mike Holt
AFCIs vs. GFCIs: What is the difference between an Arc Fault Circuit Interrupter and a Ground Fault Circuit Interrupter?
What is the difference between an AFCI Arc Fault Circuit Interrupter and a GFCI Ground Fault Circuit Interrupter? The AFCI should not be confused with the GFCI or ground fault circuit interrupter.
An AFCI is a device intended to prevent a fire. It detects a type of arcing in the electrical circuit that can lead to overheating and a fire.
A GFCI is a device intended to prevent electrical shock. A GFCI will not necessarily detect the type of electrical arcing that can cause a fire.
A ground fault is an unintentional electric path diverting current to ground. Ground faults occur when current leaks from a circuit.
How the current leaks is very important. If a person’s body provides a path to ground for this leakage, the person could be injured, burned, severely shocked, or electrocuted.
The National Electrical Code requires GFCI protection for receptacles located outdoors, in bathrooms, garages, kitchens, crawl spaces and unfinished basements; and at certain locations such as near swimming pools.
A combination AFCI and GFCI can be used to satisfy the NEC requirement for GFCI protection only if specifically marked as a combination device.
InspectAPedia Note: don't confuse this "combination" with the "Combination AFCI described earlier in this article.
While we're discussing the 2008 electrical code changes for AFCI's let's also update ourselves about GFCI's:
NEC 210.8 is the code section pertaining to GFCI's. (AFCI's are addressed in NEC 210.12.). These GFCI requirements are intended to address residential electrical wiring using 15A or 20A 120V electrical receptacles and circuits. Heavier-duty circuits such as a 30A welder circuit are excluded.
Basically GFCI protection requirements have been expanded to all basement, garage, and accessory building receptacles, and a wording change to drop "receptacles" and keep "outlets" expands GFCI coverage in other areas.
Basement GFCI changes: The GFCI protection requirements for receptacles in basements, garages, and accessory buildings have been expanded to all 125-volt, single-phase, 15- and 20-ampere receptacles regardless of accessibility or movability of an appliance from one location to another. - Minnesota Electrical Association
A Summary of Current (2008) Residential Ground Fault Circuit Interrupter GFCI Requirements
GFCI's are required safety devices to be installed in the following locations:
In 2004 Schneider Electric issued a recall of early model Square D® AFCIs manufactured between March 1 2004 and September 23, 2004 because tests indicated that "... arc detection in these breakers may become inoperable due to an issue with a third party-supplied internal component in the electronic detection unit."
Schneider's letter emphasized in an opening statement that "... Square D Company, the leading manufacturer of electrical equipment, is committed to the safety of our people, our customers, and our products." The company's letter provided additional detail:
[The company was concerned about inaccurate and misleading information in the electrical products market and asked that concerned parties turn to them for information regarding their products, including AFCIs.]
See FREEZE-PROOF A BUILDING where we describe GFCI protection on heat tape circuits powering heat tapes for manufactured and mobile homes. Similar issues regarding building water entry control are discussed at Sump Pump Inspection.
Current Limits of Protection of combination AFCI devices as sold & installed
Reader Question/Comment: You and your readers should take a look at Combination AFCIs" What they Will and Will Not Do - an IEEE publication available for public non-commercial use - Steve 1/31/2013
Repeating Steve's suggestion 1/31/13 that we read Joe Engel's paper on Combination AFCIs, we contacted Mr. Engel as well, and appreciate your contribution of a publicly-available copy of this important paper. Indeed thanks to a pointer from Dr. Jess Aronstein, we contacted Dr. Engel and have discussed AFCI issues by private email. I was concernred that his article was not available for free to the public, as it appeared in an IEEE publication. However both reader Steve and Dr. Engel have provided links to this document.
In the references section to this article as well as immediately below we include a reference and link to Dr. Engel's critical article about combination AFCIs and their capability.
My understanding of a fundamental concern is that as presently mandated, defined, manufactured and marketed, AFCIs do not provide the protection that was the original intent of Dr. Engel  as he has made amply cleaer .
Below are excerpts from the conclusion of this important article:
Reader Question: Electrician complains of nuisance tripping and AFCI failure-to trip
I'm still asking how these AFCI devices became code prior to it being available on the market and proven effective. To date I have encountered false tripping from these devices where a HO was nearly overcome from fumes from bedroom gas fireplace, other nuisance tripping from TVs, Vacuums, Hair dryers.
I have a picture of one of these breakers with a molten branch circuit conductor emminating from a loose connection on the AFCI breaker itself, another report of a fire that started in a ceiling fan box where the AFCI also failed to trip. These devices are absolute garbage made code by the manufacturers on the NFPA to boost revenue. Somebody here show me some proof of them actually preventing a fire other that remaining on and tripping for sudden loads from appliances. - Honest Electrician 9/3/2011
Honest, you should contact the US CPSC directly to make your concerns known. We publish studies and field reports on various electrical hazards but have no financial interest in the sale of any products or services.
How to Report an AFCI or other Electrical or Product Failures or Incidents to the U.S. CPSC
Please use the CPSC form found at saferproducts.gov/CPSRMSPublic/Incidents/ReportIncident.aspx
To comment on or suggest additions to this article use the Comments Box found below, or use our email found at CONTACT
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Frequently Asked Questions (FAQs)
Question: AFCI vs grandfathering homes older than 2008
This does not address grandfathering for homes older than 2008! - John, 7/24/2011
Granfathering and the AFCI requirement: good point, John. We find a variety of opinions among building code officials. At a recent building addition project the BCO wanted AFCIs in the new sub panel in keeping with the new electrical code AFCI recommendations, but he also decided that other areas in the home needed certain updates too.
Other electrical inspectors and building code inspectors look only at the new work - I'd say that's the most common case. Only when an older home is being renovated to include electrical work will most inspectors call for current codes to be complied-with.
Question: are AFCI's required on lighting-only circuits?
do you have to use arc fault on lighting only circuits? - Hugh Owen 8/22/2011
Yes. On the illustrations I've seen the overhead lighting circuits were included. see 210.12(B) Dwelling Units - quoting the Minnesota Electrical Association reference found at the bottom of this article:
I don't have space in the panel to make proper ground bus connections. - Roger 9/11/11
Roger, as long as your panel won't be overcrowded, you can always add an additional ground bar (or neutral bar) in the existing panel, connecting it to the originals and locating it where your AFCI white wire will reach.
I have a Sylvania main breaker panel in an existing dwelling. I am adding 3 circuits to basement finish.
Any AFCI breaker sold at any electrical supplier will be code compliant. Just how well the product works is a different issue as discussed in this article. Be sure to see the comments and links to Dr. Engel's paper given in FAQs. below.
Question: having trouble wiring 14-3 wired homes
How to deal with 14-3 wired rooms. I need AFCI for the outlets and the lighting, I have wired 14-3 and would need a special AFCI that doesn't seem to be offered by Square D. - Eric J 5/22/2012
In sum, AFCI's are NOT going to work properly on shared-neutral electrical circuits; niether do GFCIs.
Question: Nuisance Tripping of AFCI devices on circuit used to power a TV
I have two Seimen's AFCIs for 3 bedrooms. They were placed approx spring 2004 in a new build. No problems until several months ago with LED TV in master bedroom. Breaker would trip upon trying to turn on tv on rare occasion. At first seemed overload but now it trips every time TV is turned on.
TV is tripping the other AFCI in the other bedrooms as well. It IS NOT tripping the standard breakers elsewhere in the house. Are these older model AFCIs needing replaced to handle the load of the new appliances? Have new breakers become more reliable as stated above at avoiding nuisance tripping (which I assume this is)? - Kathy 8/20/2012
Reply: how to report AFCI problems to the US CPSC:
You are reporting nuisance tripping.
You should also contact the US CPSC directly to make your concerns known. Use this US CPSC Incident Report Form to report Zinsco or Sylvania-Zinsco equipment failures and problems. Please also report incidents to this web author.
Question: nuisance tripping of AFCI circuit with ham radio equipment.
i have ham radio equipment
Paul this sounds like another instance of nuisance tripping. You can replace the AFCI with a standard breaker and stop the tripping problem; you will be giving up what limited added safety protection the AFCI offered, and you could face a technical issue with your local electrical inspector.
You should also contact the US CPSC directly to make your concerns known. Use this US CPSC Incident Report Form to report Zinsco or Sylvania-Zinsco equipment failures and problems.
Please also report incidents to this web author.
Questions/comments: on AFCI's: Reference to Engel (2012)
DanJoeFriedman (mod) said:
Repeating Steve's suggestion 1/31/13 that we read Joe Engel's paper on Combination AFCIs, we contacted Mr. Engel as well, and appreciate your contribution of a publicly-available copy of this important paper. In the article above we include a reference and link to
Joseph C. Engel, PhD., IEEE, "Combination AFCIs" What they Will and Will Not Do", IEEE, 2012
(Sept 2, 2011) Honest Electrician said:
How much money has been paid to the NFPA to make AFCI breakers code since there have been arc outs and fires on protected circuits and they were introduced as code before they were available
Questions: AFCI be used to protect Alum branch wire circuits
(Sept 19, 2014) Mike said:
Can a AFCI be used to protect Alum branch wire circuits
Yes, and no.
yes if the AFCI is connected using CPSC-recommended methods (AMP TYCO COPALUM or the King Innovations AlumiConn) to connect the device to the circuit
No if you are thinking of direct-wiring the device to the aluminum wire. I have personally seen an aluminum wired test circuit overheat and begin to burn (we turned off power at that point) while powered through an AFCI.
Your US CPC Incident report form link is obsolete. Here's the new link:
Use the "Click to Show or Hide FAQs" link just above to see recently-posted questions, comments, replies, try the search box just below, or if you prefer, post a question or comment in the Comments box below and we will respond promptly.
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