Old House-No ARC faults

[Tom McDonnell]

Anyone know if older electrical systems can be updated to include AFCI's? I suspected not but don't really know. Also, if AFCI breakers are available, I would think the cable assembly would need to have a ground conductor.

[Vern Heiler]

Anyone know if older electrical systems can be updated to include AFCI's? I suspected not but don't really know. Also, if AFCI breakers are available, I would think the cable assembly would need to have a ground conductor.

Here is an excerpt from UL site. Grounds are not required.


The Carbonized Path Arc Ignition Test is a non-contact arcing test conducted
with NM-B cable with a series insulation cut. Tests are conducted with arcing
currents of 5 A, 10 A, rated current, and 150% rated current. The
Branch/Feeder, Combination, and Outlet Branch Circuit AFCIs are subjected to
the Carbonized Path Arc Ignition Test. The Outlet Branch Circuit AFCI is
subjected to the Carbonized Path Arc Ignition Test with the arcing occurring
upstream, to represent series arcing in the branch circuit wiring between the
origin of the branch circuit and the first outlet receptacle. The Outlet Branch
Circuit AFCI is also subjected to the Carbonized Path Arc Ignition Test using NMB
cable without a grounding conductor, as may be found in some older homes
built over 40 years ago.

[Jim Robinson]

If the house has 12-3 wire sharing the neutral, those circuits will not be able to use the AFCI breakers. The ground is not necessary, as stated earlier.

[Speedy Petey]

If the house has 12-3 wire sharing the neutral, those circuits will not be able to use the AFCI breakers. There are some brands of two-pole AFCI breakers that work for this purpose. Some.....not many.

[Jerry Peck]

If the house has 12-3 wire sharing the neutral, those circuits will not be able to use the AFCI breakers.


There are some brands of two-pole AFCI breakers that work for this purpose. Some.....not many.

As I recall, having exchanged e-mails with Siemens (may have been Cutler-Hammer) they said that if the AFCI is rated 120 volts / 240 volts, then the AFCI will work on a multiwire circuit, however, if the AFCI is rated 240 volts (only, not 120 volts also) then the AFCI will not work on multiwire circuits.

[Bill Kriegh]

I'd be somewhat curious as to why there would be a 240 volt only AFCI when they are only required on 120 volt circuits. The NEC 2011 draft doesn't show any contemplated requirements for a 240 volt AFCI so the earliest possible requirement would be 2014.

Presently, Siemens is the only company I'm aware of marketing a 2 pole AFCI breaker, and it is available in one version (with 15 or 20 AMP ratings) designed to be used on multiwire (shared neutral) branch circuits. Siemens literature indicates the intent is the device be used on a multiwire circuit and it therefore can't be used on a 240 volt circuit because it isn't listed for the application.

What the 2011 draft DOES have is a requirement that would mandate an AFCI receptacle be installed, or the circuit be AFCI protected, when a receptacle would have to be AFCI protected because of location if the receptacle is replaced. This is like the current GFCI rule.

I look for MAJOR issues here when homeowners find out it's going to cost between $35.00 and $40.00 to change a receptacle and can virtually guarantee that people who would never dream of changing a receptacle will start doing so.

[Speedy Petey]

I'd be somewhat curious as to why there would be a 240 volt only AFCI when they are only required on 120 volt circuits. The NEC 2011 draft doesn't show any contemplated requirements for a 240 volt AFCI so the earliest possible requirement would be 2014.
I was wondering the same thing. :confused:

[John Kogel]

I'd be somewhat curious as to why there would be a 240 volt only AFCI when they are only required on 120 volt circuits. They may be making them for the overseas market, UK for example? They are an international company.

I can just imagine British handymen in 300 year old brick cottages messing around with 240 volts, yikes! :)

[Jerry Peck]

First up, code prior to the 1970's did not establish EGC connections for switches when the 3 prong receptacle came on the market...


I am traveling and do not have access to my codes, but grounding to the metal strap of the switch came in at the same time grounding for receptacles came in, to my best recollection - I will need to verify that when I get back to my office toward the end of next week.