Hello all... Ive got an issue here. Im upgading a residential service from 100A to 200A. in looking at the service a privious electrian has moved the older panel from inside (closet) to the exterior. he installed the 100A panel with most of the circiuts extended with 12/3NM. most of the house is now on multiwire circuits.The new panel will requier AFCI breakers for the bedrooms. these cannot be installed on shared neutral circiuts. The old location for the first panel is "around the corner" from the new panels. so pulling new extentions for these lines will involve a LOT of drywall/paint work.. should i run from this project?
Sandro, there seems to be an issue, as to whether there will ever be a two-pole combination type AFCI. I have seen a memo, purportedly from NEMA (note that I am still not convinced of it's authenticity), that essentially says "too bad" if the lack of two pole AFCI's eliminates the use of multi-wire branch circuits.
The 2008 NEC also introduces plenty of restrictions on the use of the "shared neutral." It's almost as if they want to discourage the practice.
On the bright side .... there is an opening for AFCI devices. While the code still calls for the run to the panel to be in a metal raceway, IMO device AFCI's are ideal for old work, such as you describe.
Greg, you are correct ... and the attitude of the code panel towards the use of AFCI's in old work is but one of the many tangents to this thorny issue.
Sandro, I'm a bit puzzled myself; that's part of the reason I am not ready to accept that "memo" as genuine. At any rate = and I have to go by hearsay, lacking direct experience - the AFCI for this year is somehow different from the AFCI from last year. Hence, the name "combination AFCI."
ECN is one of the most popular internet electrical forums. The entire mess could be solved, if only one of our established members - and I know you're out there - would come out and say "I work for "X," we make combo AFCI's for use on multi-wire branch circuits, they are in the distribution pipeline, and you should have no trouble getting them." So far, that statement has not been made.