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Modification or not

ICE

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212.12(D) Branch Circuit Extensions or Modifications — Dwelling Units, Dormitory Units, and Guest Rooms and Guest Suites.Where branch circuit wiring for any of the areas specified in210.12(A), (B), or (C) is modified, replaced, or extended, the branch circuit shall be protected by one of the following:

The situation is the following. The existing 200A residential service panel is located on an exterior wall of a garage. There is 30 slimline breakers and the customer wants a service upgrade with a sub-panel in the garage. The existing circuits can be intercepted and land at the sub-panel without adding conductor. The circuits would in fact have less conductor.

Would this require AFCI protection for the circuits in the sub-panel for those circuits that require AFCI in section 210.12(A).
Is this a modification per code. Keep in mind that the new sub-panel seems to not be an issue given that a new main service panel can be installed without AFCI as long as there is no additional conductor length greater than six feet. Again, if a new service panel is not a modification that would trigger AFCI protection does it make sense to decide that the sub-panel is a modification?


210.12(A) Dwelling Units. All 120-volt, single-phase, 15- and 20-ampere branch circuits supplying outlets or devices installed indwelling unit kitchens, family rooms, dining rooms, livingrooms, parlors, libraries, dens, bedrooms, sunrooms, recreation rooms, closets, hallways, laundry areas, or similar rooms or areas shall be protected by any of the means described in 210.12(A) (1) through (6):
 
The wording of the exception to 210.12(D) is (2020 NEC):

"Exception: AFCI protection shall not be required where the extension of the existing branch circuit conductors is not more than 1.8 m (6 ft) and does not include any additional outlets or devices, other than splicing devices. This measurement shall not include the conductors inside an enclosure, cabinet, or junction box."

I'll go with shortening the existing branch circuit conductors is a negative length extension, and any negative number is less than 6. So it complies with the exception.

Cheers, Wayne
 
The AHJ has decided that the introduction of the sub-panel is a modification and as such, AFCI protection is required. Lacking a definition or guidance to the contrary, I fail to identify an argument.
 
The AHJ has decided that the introduction of the sub-panel is a modification and as such, AFCI protection is required. Lacking a definition or guidance to the contrary, I fail to identify an argument.
Although the exception appears to apply, I cannot argue with the logic of the AHJ in this case. One of my neighboring communities requires panel changes to implement AFCI protection. We don't here, but that is the interpretation that has been adopted for the past few years by them for the good of the community.
 
a BC here not a electrical inspector, the sub panel is new work so the more restive requirement should apply, install AFCI.
 
It is unequivocal that for a simple panel change out that is like for like in the same location, 210.12(D) Exception means that no AFCIs are required. This is the whole reason the exception was added to the 2014 NEC and is documented by the ROP/ROC change process at nfpa.org. Any jurisdiction interpreting the Exception contrary to that is wrong.

In fact, the Exception says you can move the panel over up to 6', and extend some of the branch circuits up to that amount (the ones coming in from the opposite direction) and still no AFCI is required.

The OP concerns moving the panel so that none of the branch circuits would need to be made longer, and in fact they all could be made shorter. So if the branch circuit wiring is left at the same length, and the excess wire is just left in place, again it is clear that no AFCI is required.

But maybe that's messy, so it makes more sense to shorten the branch circuit wiring. Seems to me that shortening the wiring meets the limitation of "extension . . . of not more than 6 ft" and so it also meets the Exception.

Cheers, Wayne
 
Not an extension or modification per classic interpretation of the NEC.

The NEC is written in a way that you do have to find the national consensus of what it means to have the correct interpretation, you can't just go with however the words on the page might look to you. Article 90 indicates the NEC is not written for people who don't already know what it means.
 
It is unequivocal that for a simple panel change out that is like for like in the same location, 210.12(D) Exception means that no AFCIs are required.
But it's a new panel in a new location. And it was a service panel and new one will be a sub panel. Is that really "like for like in same location"?
 
But it's a new panel in a new location. And it was a service panel and new one will be a sub panel. Is that really "like for like in same location"?
It's not, but 210.12(D) doesn't require "like for like in the same location." I just used that case as a starting point for the reasoning in my previous post.

Basically, unless you add a new device to the branch circuit, or extend the wiring by more than 6 feet, 210.12(D) Exception applies, and you don't need to add AFCI. The changes described in the OP meet neither of those triggers. If you're concerned about the simultaneity of the two changes you mentioned, new location and the change from service panel to subpanel, just consider each one individually.

New location: that's the whole point of the 6' allowance in the Exception. E.g. old panel was in a closet, new panel has to move around the corner and face the other way. We can even move the panel more than 6', as long all the branch circuits are coming into the area in a way that no branch circuit requires extending more than 6'.

Changing from service panel to subpanel: consider the case that we are just adding a service disconnect in front of an existing service panel, and all we do to the service panel is remove the MBJ, move any GECs over to the new service disconnect, and separate neutrals and grounds. Obviously does not trigger 210.12(D).

Cheers, Wayne
 
The branch circuit, meaning the wiring from the panel to the devices, is not changing in any appreciable way. The panel itself is not required to have AFCI protection, only the branch circuits. The AFCI protection has nothing to do with the panel except that the panel is a convenient place to put the AFCI's.

It would be similar to requiring GFCI protection to be added at the panel if it serves a basement per the 2020 code, even though the basement wasn't touched. Or changing the receptacle spacing on a kitchen island to meet either the 2020 or 2023 NEC because it is attached to the branch circuit served from the new subpanel.
 
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It would be similar to requiring GFCI protection to be added at the panel if it serves a basement per the 2020 code, even though the basement wasn't touched.
It's just a slight drift Jeff, and it is my thread. I wouldn't bring it up had BN4537 not mentioned basements,,,and I disagree with his statement. So to that end I drew a parallel to swimming pools.

We do not have many basements but we do have a lot of swimming pools. On service panel upgrades, I require GFCI protection on pool equipment. Contractors complain, and when I suggest that we consult the customer they usually become demure.

My reasoning is that GFCI protection on swimming pool circuits is a life safety issue. Some have said that the kitchen counters lack GFCI protection and that is also a life safety hazard so why just the swimming pool. My answer to that has been. "Well now that you have made me aware, provide GFCI protection for the kitchen counter receptacles... oh and don't forget the one under the sink." "Now have you been in the garage?" "How about the bathrooms?" "Or perhaps you'd be happy to GFCI the pool pump motor and stop complaining."
 
I guess you can't get too morally outraged with the current AHJ, lol
Well here's the thing about that. The example in the OP is my home. I am preparing to install a 26kw generator. The service panel is 35 years old with a configuration that makes it difficult and the contractor says that I need an upgrade. I suggested the sub-panel as a way to make room for AFCI breakers and the contractor is convinced that AFCI would not be required. I agreed but in fact I do not see the logic in changing out the service and not taking advantage of the additional protection that AFCI provides.

I am reminded of owners that replace roof underlay and reinstall the old tile. For another $5k I got a new roof that looks new. It's like new tires, I can feel the difference in the ride.
 
the additional protection that AFCI provides.
If you are choosing to do this voluntarily in the interest of safety, stick with the AFCI brands that have not eliminated ground fault sensing. That would be "Eaton CH, Siemens Non Plug On Neutral, Square D HOM and Square D QO" (per this post https://forums.mikeholt.com/threads...-when-they-should.2585246/page-2#post-2970024 )

I'm not aware of any significant evidence that AFCI breakers actually do anything to improve safety. At least with the AFCIs that also do ground fault sensing (often at a higher threshold than GFCI requires, so they are not GFCI), you know that the ground fault sensing will detect minor problems with the wiring, like a neutral-ground contact or neutrals crossed between different branch circuits.

Cheers, Wayne
 
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Well here's the thing about that. The example in the OP is my home. I am preparing to install a 26kw generator. The service panel is 35 years old with a configuration that makes it difficult and the contractor says that I need an upgrade. I suggested the sub-panel as a way to make room for AFCI breakers and the contractor is convinced that AFCI would not be required. I agreed but in fact I do not see the logic in changing out the service and not taking advantage of the additional protection that AFCI provides.

I am reminded of owners that replace roof underlay and reinstall the old tile. For another $5k I got a new roof that looks new. It's like new tires, I can feel the difference in the ride.
And don't forget surge suppression....
 
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