Residential Arc Faults:

 

 

Arcing between conductors produces light and heat and is blamed for an electrical fire every five minutes in the United States. These are low power arcs of a few amps on a 115 VAC circuit. An arc of a hundred watts can set wallboard, carpet, cloth, wooden studs, etc on fire. You may be familiar with Ground Fault Interrupters (GFI) for your house. Three companies now produce Arc Fault Circuit Interrupters (AFCI) for residential uses. As of 2002 AFCI Breakers are required by the National Electric Code (NEC) to be installed in the bedrooms of all new constructed houses. Every locality must individually accept the NEC recommendations and thus AFCIs may not yet be required in your town or county.

 

GE defines “An arc fault as an unintentional electrical discharge characterized by low and erratic current that may ignite combustible materials.”

General Electric: http://www.geindustrial.com/cwc/products?famid=8&catid=36&id=cb-qafci

 

Cutler-Hammer has some good photographs of residential arc faults at : http://www.arcfault.com

 

SquareD: http://www.squared.com. One of the better brochures on AFCIs can be found by Square D at http://www.squared.com/us/products/circuitb.nsf/07a0210021262d45862564b5006e4f84/bea8c320ac2c9e35852566330062fe35/$FILE/ATTQCVJ1/0760HO9801R902.pdf. An excellent technical paper by Square D on AFCIs can be found at http://www.hq.usace.army.mil/cemp/e/Et/arcfault.pdf.

 

A data sheet on the Siemens AFCI can be found at http://www.sea.siemens.com/resident/product/S3017.pdf.

 

The US Consumer Produce Safety Commission states “Problems in home wiring, like arcing and sparking, are associated with more than 40,000 home fires each year. These fires claim over 350 lives and injure 1,400 victims annually. Their position on AFCI breakers can be found at http://www.cpsc.gov/cpscpub/pubs/afci.html. The CPSC has data sheets on AFCIs at http://www.cpsc.gov/cpscpub/pubs/afcifac8.pdf.

 

 

The UL code states “By recognizing characteristics unique to arcing and functioning to de-energize the circuit when an arc-fault is detected, AFCI's further reduce the risk of fire beyond the scope of conventional fuses and circuit breakers. The UL page at http://www.ul.com/regulators/afci/ leads to details of how AFCI breakers are tested in the UL laboratory. The UL 1699 defines the requirements for the new AFCI breakers. Work on AFCIs by the UL can be traced back to a 15 March 1996 UL report of Research on Arc-Fault Detection Circuit Breakers which was based upon research that extends back into 1994. While AFCIs are specified to detect several different types of arcing faults, they will not detect all types of arcing faults, http://www.ul.com/regulators/afci/Dini.pdf. The UL 1699 Standard currently addresses four different types of arcing tests with different types of wires and insulation cuts, 15 different unwanted tripping tests, and 14 tests for overloads, short circuits, and mechanical operation.

 

A word of caution about the overselling of AFCIs. The risk of fires caused by arcing is real and the total US loss to electrical fires is large. AFCIs can help to reduce that risk, but it will not completely solve the problems. Most electrical fires occur in older homes with older wiring and the NEC doesn’t require AFCIs in existing homes. UL 1699 specifies testing with NM cable with ground. Much of the older wiring does not contain a ground and thus may not benefit from AFCIs in the same way. AFCIs may be of particular benefit in houses containing aluminum wiring if the needed ground is available.

 

Zlan Ltd at http://www.zlan.com/ has the best description of how conventional circuit breakers and how AFCIs operate. They even have links to important patents describing AFCIs.

 

How do you verify that your AFCI is installed correctly and fully functional? I have no personal experience with the product, but Fox Meters has announced a new product line for field testing of AFCIs. Every electrician that installs AFCIs should have such test equipment available. http://www.arcfaulttester.com/

 

An IEC fact sheet on AFCIs can be found at http://www.iecouncil.org/educational/FS28.html.

 

AFCI technology continues to improve and to have its detractors. The National Association of State Fire Marshalls published an investigation in a NASFM document entitled, "AFCI Inquiry and Report," dated August 1, 2002. The report will be distributed to state and local government, electrical code officials, trade associations, and fire service agencies. A copy can be found at: http://www.firemarshals.org/issues/home/electrical_fires.html

However the National Electrical Code Internet connection operated by Mike Holt Enterprises raises some legitimate concerns with the breakers. http://www.mikeholt.com/mojonewsarchive/AFCI-HTML/HTML/Scientific_Assessment_-_Arc_Fault_Circuit_Interrupter_Technology_prevents_electrical_fires~20021031.htm

State Farm Insurance is on record in support of the AFCI technology. http://www.statefarm.com/consumer/vhouse/articles/afci.htm Perhaps the important thing to remember is that while these breakers do operate and correctly detect many types of arcing failures, they do not detect all types. No breaker give compete protection against all types of faults.

 

Please contribute any additional information to info@arcfault.org.

 

 

Residential Arc Faults:

 

 

Arcing between conductors produces light and heat and is blamed for an electrical fire every five minutes in the United States.  These are low power arcs of a few amps on a 115 VAC circuit.  An arc of a hundred watts can set wallboard, carpet, cloth, wooden studs, etc on fire.  You may be familiar with Ground Fault Interrupters (GFI) for your house.  Three companies now produce Arc Fault Circuit Interrupters (AFCI) for residential uses.  As of 2002 AFCI Breakers are required by the National Electric Code (NEC) to be installed in the bedrooms of all new constructed houses.  Every locality must individually accept the NEC recommendations and thus AFCIs may not yet be required in your town or county.

 

GE defines “An arc fault as an unintentional electrical discharge characterized by low and erratic current that may ignite combustible materials.”

General Electric:  http://www.geindustrial.com/cwc/products?fam id=8&catid=36&id=cb-qafci

 

Cutler-Hammer has some good photographs of residential arc faults at :  http://www.arcfault.com

 

SquareD:  http://www.squared.com.  One of the better brochures on AFCIs can be found by Square D at http://www.squared.com/us/products/circuitb.nsf/07a0210021262d45862564b5006e4f84/bea8c320ac2c9e35852566 330062fe35/$FILE/ATTQCVJ1/0760HO9801R902.pdf.  An excellent technical paper by Square D on AFCIs can be found at http://www.hq.usace.army.mil/cemp/e/Et/arcfault.pdf.

 

A data sheet on the Siemens AFCI can be found at http://www.sea.siemens.com/resident/product/S3017.pdf.

 

The US Consumer Produce Safety Commission states “Problems in home wiring, like arcing and sparking, are associated with more than 40,000 home fires each year. These fires claim over 350 lives and injure 1,400 victims annually.  Their position on AFCI breakers can be found at http://www.cpsc.gov/cpscpub/pubs/afci.html.  The CPSC has data sheets on AFCIs at http://www.cpsc.gov/cpscpub/pubs/afcifac8.pdf.

 

 

The UL code states “By recognizing characteristics unique to arcing and functioning to de-energize the circuit when an arc-fault is detected, AFCI's further reduce the risk of fire beyond the scope of conventional fuses and circuit breakers.  The UL page at http://www.ul.com/regulators/afci/ leads to details of how AFCI breakers are tested in the UL laboratory.  The UL 1699  defines the requirements for the new AFCI breakers.  Work on AFCIs by the UL can be traced back to a 15 March 1996 UL report of Research on Arc-Fault Detection Circuit Breakers which was based upon research that extends back into 1994.  While AFCIs are specified to detect several different types of arcing faults, they will not detect all types of arcing faults, http://www.ul.com/regulators/afci/Dini.pdf.  The UL 1699 Standard currently addresses four different types of arcing tests with different types of wires and insulation cuts, 15 different unwanted tripping tests, and 14 tests for overloads, short circuits, and mechanical operation. 

 

A word of caution about the overselling of AFCIs.  The risk of fires caused by arcing is real and the total US loss to electrical fires is large.  AFCIs can help to reduce that risk, but it will not completely solve the problems.  Most electrical fires occur in older homes with older wiring and the NEC doesn’t require AFCIs in existing homes.  UL 1699 specifies testing with NM cable with ground.  Much of the older wiring does not contain a ground and thus may not benefit from AFCIs in the same way.  AFCIs may be of particular benefit in houses containing aluminum wiring if the needed ground is available.  

 

Zlan Ltd at http://www.zlan.com/ has the best description of how conventional circuit breakers and how AFCIs operate.  They even have links to important patents describing AFCIs. 

 

How do you verify that your AFCI is installed correctly and fully functional?  I have no personal experience with the product, but Fox Meters has announced a new product line for field testing of AFCIs.  Every electrician that installs AFCIs should have such test equipment available.  http://www.arcfaulttester.com/

 

An IEC fact sheet on AFCIs can be found at  http://www.iecouncil.org/educational/FS28.html.

 

AFCI technology continues to improve and to have its detractors. The National Association of State Fire Marshalls published an investigation in a NASFM document entitled, "AFCI Inquiry and Report," dated August 1, 2002. The report will be distributed to state and local government, electrical code officials, trade associations, and fire service agencies. A copy can be found at: http://www.firemarshals.org/issues/home/electrical_fires.htm l

However the National Electrical Code Internet connection operated by Mike Holt Enterprises raises some legitimate concerns with the breakers. http://www.mikeholt.com/mojonewsarchive/AFCI-HTML/HTML/Scientific_Assessment_-_Arc_Fault_Cir cuit_Interrupter_Technology_prevents_electrical_fires~20021031.htm

State Farm Insurance is on record in support of the AFCI technology. http://www.statefarm.com/consumer/vhouse/articles/afci.htm Perhaps the important thing to remember is that while these breakers do operate and correctly detect many types of arcing failures, they do not detect all types. No breaker give compete protection against all types of faults.

 

Please contribute any additional information to "arc@arc?fault.org" But first take out the ? that I placed there to reduce the spam.