Arc Fault - ECN Electrical Forums

I know it been a while since I logged in, but I browse almost every night. I would like some input on a question that came up at the supply house. They are telling me the local inspector it requiring us to install 14-2-2 romex for the bedrooms. Now I have installed many Arc fault with regular 14-2 romex. Has anyone else hear of this. The 14-2-2 has two nuetrals going to it. One on the breaker and the other to the bar. Thanks

The only person that has the corect answer is the inspector or you could try and ask for the amendments/electrical code. Many places here have their building code online.

We don't use Romex here but the first thing I thought of was what if you only had a 1 BR home. Or a 2 BR you wanted to put on 1 circuit. What if the 2 BR home had the BR's on different floors or sids of the house.

My guess is just another code mith. Probibly came about by an apprentace saying why do we need to use this stuff and an owner not wanting to explain just saying bucause it's code now.

What would you do with the second neutral?
You need two current carrying conductors with balanced current on each. Any connection to another neutral would trip the breaker.

Considering that you are getting this information 3rd hand at the supply house counter, I would pay little head to it.

Active 1's advice about checking the local codes is a wise idea. Although there in no physical difference electricaly speaking in having 2 circuits in either (2) 12/2 cables, or a single 12/2/2 cable, there may be some other factor. For instance, localy I am required to have all conductors identified by the phase they are on, and not 'technically' the way the local code is written to phase tape them for identification, they need to have the color in the pigment of the insulation. So that means I would either have to get red/white conductor romex, or use 12/2/2. (Or 14/2/2 depending on the circuit.) FYI CH makes a 3-wire AFCI breaker....

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One on the breaker and the other to the bar.

I have no idea what purpose that would serve or why it would need to be done.... Sounds BOGUS......

Sounds to me as though the guys at the supply house get a commission on their sales.

Roger

I'll check with the inspector on Monday. Just wondering what everyone else uses or has heard of this. Thanks

Never heard of any of this throughout the Florida romex panhandle...

This is from-

http://www.mikeholt.com/mojonewsarchive/AFCI-HTML/HTML/AFCI_Update~20030320.htm

12-2-2 NM “Romex” was introduced to allow home runs for two AFCI circuits, as an AFCI can not have a shared neutral (due to ground fault protection). However, at least one manufacturer (Cutler Hammer) offers a 2-pole AFCI for home runs. Standard 12-2-1 NM “Romex” can be used. The 2-pole AFCIs are available with/without common trip for overcurrent and overload conditions; the trip is always common for an arcing or ground fault.

Robbie, that makes sense.

Roger

All this to save a ground wire?
I can't imagine you are saving that much money.

I agree. I would run seperate circuits.

umm, considering that 12-3 costs twice what 12-2 does, I cant imagine 12-2-2 being anything but a huge waste of money, I can't see the labor savings adding up to the extra wire cost, only real use of 12-2-2 that I can see is three phase in commercial

just conjecturin'
-Will

I just reviewed our wire prices for 14/2, 14/3 & 14/2/2.

14/3 is 25% more than 14/2. 14/2/2 is 76% more than 14/2. Based on these prices 2 runs of 14/2 will cost 13% more than a single run of 14/2/2 in materials alone. Add the additional to that and I definitely see the savings.

Curt

I have seen 12-2-2 used only on one job. It was used as a home run for the Bathroom with a GFI breaker for the receptacle and the other 12/2 for the light.
Don't know about the cost but, it made a neat appearence in the two gang box. Switch and recept.
Alan--
Are the Smoke detectors on the AFCI circuit ? If not, that may be the reason for the seperation.

[This message has been edited by Alan Nadon (edited 01-16-2007).]

The 14-2-2 is for only multi circuits. Talk to the inspector finally.

Wouldn't 14-2-2 be subjected to derating and only good for 12A?

Originally posted by E57 , quote"Active 1's advice about checking the local codes is a wise idea. Although there in no physical difference electricaly speaking in having 2 circuits in either (2) 12/2 cables, or a single 12/2/2 cable, there may be some other factor. For instance, localy I am required to have all conductors identified by the phase they are on, and not 'technically' the way the local code is written to phase tape them for identification, they need to have the color in the pigment of the insulation. So that means I would either have to get red/white conductor romex, or use 12/2/2. (Or 14/2/2 depending on the circuit.) FYI CH makes a 3-wire AFCI breaker...."

I am only just curious about this local code amendment you are describing. Do they apply this to single phase 240/120 volt residential systems? If so, why? The system is single phase. Both hot conductors are on the same phase.

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I am only just curious about this local code amendment you are describing. Do they apply this to single phase 240/120 volt residential systems? If so, why? The system is single phase. Both hot conductors are on the same phase.

Yes, but not always enforced, the inspectors acually have to remind themselves about it.... And that reminder usually comes in the form of all black phase conductors, or big lumppy gobs of tape on them. Yes, in residential too. As not all residential is the same. Example mid and high-rise buildings are often 3 phase 208, but only using 2 phases, and there are parts of the city that have split delta systems and allowed the high-leg into the buildings (Big old mansions) for elevator use. As well as the many converted industrial areas that al now 'live/work'.... There are also a few 2 phase areas, and even if single phase the 'phases' are of are of additive voltage, so..... I see the point here.

Any this is that code....

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210.5(C). Add the following new section:

(C) Ungrounded Conductors. Underground conductor insulation shall be color coded as follows:

See Section 200.7 for limitations on re- identification of white or gray conductors.

(1) 120/240 volt 3-wire circuits - “A” phase black, “B” phase red; 120/208 volt 4-wire 3-phase wye circuits - “A” phase black, “B” phase red, “C” phase blue; 120/240 volt 3-phase delta circuits - “A” phase black, “B” (high leg) phase purple, “C” phase red; 277/480 volt 4-wire 3-phase wye circuits - “A” phase brown, “B” phase orange, “C” phase yellow; ungrounded conductors for other voltages shall be identified by different color coding, marking tape, tagging, or other approved means.

(2) Conductors for switch legs may be ofa different color than the ungrounded circuit conductor when suitably identified at pull, junction and outlet boxes with marking tape, tagging or other equally effective means. The color green, white or grey shall not be used for identification.

(3) Conductor insulation shall contain the applicable color pigment for circuit wire #14 AWG through #10 AWG. Ungrounded conductors #8 AWG and larger and ungrounded conductors of any size in cable assemblies may be suitably identified at pull, junction and outlet boxes with marking tape, tagging or other equally effective means.

Exception: Extensions of existing non-color- coded wiring systems need not be color coded.

Steve, 4 conductors are subject to derating, but in the 90c column so you are usually OK until you get over 9 (14&12) if 240.4(D) applies.