Hello, I am not familiar with AFCI because I strictl do Comm and Ind. I did the electrical work on my brother n law's house addition and ran 14/3 to feed receptacles in two new rooms. Two single pole AFCI (SquareD) breakers are not working. It will trip as soon as any load is applied to receptacle. Obviously because neutral is shared. I have read conflicting things on another site. One person states you can use a 2pole AFCI for multi branch circuits. Anothr said Square D doesnt make two pole, and another siad you CAN use two single pole. Can I run a white wire in between the single pole breakers? Any help would be great!

Run 14/2/2 -- AFCI demands dedicated neutrals for its logic. Period.

You can't use a pair of single pole AFCIs. There may be a 2 pole AFCI that will handle a multiwire circuit but I haven't seen one.
The AFCI has pretty much made the residential multi wire circuit a thing of the past. Using more copper is probably cheaper than the 2 pole AFCI to serve it.
(or so Schnider says)

http://static.schneider-electric.us...t%20Interrupters-AFCI/0760DB0203R902.pdf

Cuttler Hammer may have a "classified" AFCI breaker that is listed to fit in a SqD panel. I will not start that argument here

Ok, well the house is closed up and painted. What would you suggest I do? I have a 14/3 run to the second floor, where 14/2 goes to one room, than 14/2 to another. How can I make these AFCI. I assume the inspector will come in with a AFCI tester to plug into random receptacles?

If I am remembering correctly (this was late spring when it was roughed) I put a j box in the attic and ran the 14/3 homerun to it than split off to 14/2 to each room. I suppose I can eliminate the red on the multi wire and just use one circuit for all. I hate to do it, but if the two pole AFCI breaker will not support the single neutral I dont have a choice.

If you can't find an acceptable C/H classified breaker for your panel I think you are in trouble.
Make sure you get the listing documentation for the breaker and I think they come with a sticker for the panel.

YMMV as to how your AHJ feels about classified breakers.
It is probably worth a call before you shell out the $40-50 for the breaker.

I am a little confused? C/H...Cutler Hammer? From what the other fellow said nothing I do will work with a multi branch. If you see what I wrote at the bottom of my last post, I think that is the only solution.

I believe CH does have a 2 pole AFCI breaker that would work with a MW circuit. The question is whether it will work in your panel. Is this Homeline or QO?

QO

I put the question in to C/H. Let's see what they say.

Ok thanks. I put in a call to Eaton and left message. I also contacted customer support via email

Ayrton:
Just an FYI, there is no such creature (that I know of) as an AFCI 'tester'.

AFAIK, the only recognized 'test' is via the test button on the AFCI CB!

The last time I spoke to Sq D re: the CH breakers; they answered very quickly...NO. Speaking to CH, they said "the breaker is recognized for use in SQ D panels"

Can you get another 14/2 up to your splice box?

Of course SqD says a C/H breaker is not allowed in their installation instructions but U/L says it is listed for the application. It is a classic "listing" vs "labeling" dispute.
That is why I said you really need to ask the AHJ. That is also why CH has a sticker that you put in the panel so it is "labeled" to accept the CH breaker.

In the meetings I have been in it is always a split decision, sometimes quite vociferously. I have been in the room several times when Harvey Johnson (CH) and Jim Pawley (SqD) have had it out. The funny thing is Jim would end up staying at Harvey's house when he was in town and car pool up to the IAEI meeting.


BTW I have an off the wall (actually "in the wall" I suppose) idea. Extend the 14/3 down into a readily accessible location, mount a little 2 slot panel with 2 AFCIs and go back up to the original J box with a pair of 14/2s or just do the whole thing with some fished smurf and do it all on one raceway with THHN.
210.12 talks about branch circuits, not feeders.

I saw on a website where they sell AFCI testers. I assumed it was similiar to the tester for GFCI where you plug it into the receptacle and push the button and it should trip the gfci. How are inspectors testing the outlets in bedrooms?

No I cannot get another wire up. House is sheetrocked, patched and painted. It was tight as it is to get that 14/3 up.

Like I stated earlier, I believe I put a jbox in the attic so I could put the 14/3 in a box than split off with 14/2. I will probably have to just knix the red wire and use one circuit for both bedrooms.

That is not a "tester" it is an "indicator" or so the manufacturers say. It will trip the AFCI but it may not really be testing it.

The inspectors I know have a dance they do basically tripping the AFCIs with the test button, checking the outlets are off then resetting it. The trick is doing all of that in the least number of trips.

GE just started making arc faults that work with shared neutrals. I couldn't figure out how to link this so I cut and pasted it. This is no help to the OP unless he adds a small sub panel, but I expect the other manufacturers will follow suit.





Combination Arc Fault Circuit Interrupters
Application Guidelines
Applying 1-pole Combination AFCIs to Shared Neutral Circuits
Until now, using a shared neutral (multiwire branch circuits) on arc fault protection circuits required the
use of 2-pole AFCI breakers, since the AFCI circuitry uses a ground fault CT to help it detect arcs. But
with GE’s newly developed combination AFCI technology, no ground fault CT is required, so shared
neutral circuits can be used with two 1-pole AFCIs connected together with a handle tie (see Figure 1).
The use of shared neutral circuits produces significant copper savings when two branch circuits are
close to each other but far from the circuit breaker panel. A shared neutral circuit uses 3-conductor
NM-B wire to join two adjacent circuit breakers in the panel to a junction box near the branch circuit
loads/outlets (see Figure 2).
GE
Electrical Distribution
imagination at work
Figure 1.
Two 1-pole AFCIs with
THT104 handle tie
Figure 2.
Wiring diagram
AFCI
Panel
AFCI
12/14-3 NM-B
12/14-2 NM-B
12/14-2 NM-B
Junction box
Branch
circuit #1
(A-phase)
Branch
circuit #2
(B-phase)
AFCI pigtails
Red conductor
Note: for simplicity the ground wires are not shown
White conductor
Black conductor
Neutral bar
DET-719 (11/09)
Information provided is subject to change without notice. Please verify all details with GE. All values are design or typical values
when measured under laboratory conditions, and GE makes no warranty or guarantee, express or implied, that such performance
will be obtained under end-use conditions.
Applying 1-pole Combination AFCIs to Shared Neutral Circuits
Selection
The catalog numbers for new combination type AFCIs that are suitable for use in shared neutral
circuits are shown below. It is important to note that the MOD 3 suffix be on the breaker, as the MOD 2
suffix type AFCIs do have ground fault CTs and cannot be used in shared neutrals. MOD 3 breakers
are easily distinguishable by their gray cases and black test switches.
Installation
Connecting two 1-pole Combination AFCIs to a shared neutral circuit is easy. Before inserting the
AFCIs into the panel, connect the handles together with the handle tie (Cat. No. THT104). Then, as
shown in Figure 2, connect the black conductor to the load lug of the first AFCI and connect the red
conductor to the load lug of the second AFCI. The white conductor can be connected to the neutral
lug of either AFCI. It is not necessary to wire the two neutral lugs together. The second AFCI’s neutral
lug can remain unconnected.
The handle ties only provide manual on-off capability between one-pole devices. They do not tie the
internal trip mechanisms together. Therefore, after installation and energization, both of the AFCI’s
push-to-test switches should be tested in both the up and down positions.
This application complies with all applicable National Electric Codes and UL standards.
Amps 10kAIC Plug-In 22kAIC Plug-In 10kAIC Bolt-On 22kAIC Bolt-On
15A THQL1115AF2 THHQL1115AF2 THQB1115AF2 THHQB1115AF2
20A THQL1120AF2 THHQL1120AF2 THQB1120AF2 THHQB1120AF2
imagination at work

If it's only for 2 bedrooms and they won't be using space heaters or AC units I would think one 15 amp circuit would be plenty.

Your right, I just dont like having all those receptacles on one 15a circuit. I know resi guys do it, but I dont like it. With everything now a days than can be plugged in, the more circuits the better IMO.

Thanks for the info on the GE equip.

There, scanned and uploaded, pretty proud of myself. This appeared in Mike Holt's newsletter this week. Funny thing is the properties of the pdf show it was created in 2009.

The first sentence clearly states that you can use a 2pole AFCI for multi branch.

The problem is that GE does not seem to have a classified breaker that will work in your QO panel.

C/H sent me a message that they are still looking into it.

Thank you. I spoke to inspector this morning. He was appreciative of my situation. In his experience he said resi guys have simply just stopped running multi-wire branch circuits. In hindsight I would not have.
And asking him about the 'tester' he verified what someone hre had said. "they don't work" He told me had spent a couple hundred bucks for this Greenlee tester and it doesn't work. Unlike GFCI, the AFCI reads the sine wave. He told me to try the two pole but he thought it would give nuisance tripping. He also told me a couple stories about the nightmares these AFCI's cause. He even told me he has seen the metal staples cause tripping. Not because they penetrated th sheathing, but because the metal is affecting the sine-wave.
It is not a proven system as of yet, and IMO this is just another example of the manuf. having too much damn say in the codes.

My plan right now is to simply eliminate the second circuit. I'll just re-connect it after the inspction. And I will sleep soundly at night because I know everything was wired safely and grounded.

Just a couple of observations. The idea that multi-wire branch cct's are not being used very much is not true. It is still an economical way of dealing with two circuits fed from the panel that are located far enough away to warrant the savings or convienance of not installing two separate home runs. The split 15A receptacle is still popular because of the total wattage available versus 2 20A. The only reason the 20A became popular was the necessity to use GFCI protected receptacles near the sinks. As was noted in previous discussions on the board, you cannot protect a split receptacle using a common neutal with a GFCI breaker or plug.

My advise . . . do the job right. Only then will you sleep well because if there is ever a fire as a result of the bedroom circuit being impinged by a cord against a headboard etc you place yourself in a very sticky situation legally and morally. Abandon one of the wires on the 3 conductor in the attic JB, put the receptacles on one circuit and install a QO AFCI and be done with it. Obviously in order to do that you will need to not have put too many devices in the bedrooms. Most bedrooms you will get away with 5 receptacles and a light (although I don't like putting the light on the AFCI cct see below). The bedrooms are probably the lightest loading of anywhere so I wouldn't worry about your idea of keeping the circuit lightly loaded.

I don't buy the idea of a staple causing problems with AFCI unless it had damaged the conductors as it is not a complete loop or bonded in any way and therefore should not have any effect on the sine wave. What often wreaks havoc with AFCI's is arc producing loads including switches that are not making good contact, vaccuum cleaners, or wore out lamp bases etc. My understanding is that the AFCI is able to sense the distortion of the wave caused by these things and then trips.

As usual you will be getting opinions from Canadians as well as Americans. The codes are similar but not the same. My perspective is Canadian Electrical Code. Good luck, it is a pain when you find something like this after everything is finished.

How about a 2 circuit (or larger) GE Subpanel?

Seems like a quick solution IMHO, 2 pole in the existing panel with a compliant feed to a mini-panel, 2 pole GE AFCI....done.

Sorry . . . should have read your 2nd floor JB not attic.