do they make two pole afi breakers? and if so how expensive are they? with wire costs through the roof i wonder if the difference in breakers offset the cost of a seperate 14-2 home run in other words can one run a 14-3 afi circuit for two bedrooms?
funny qoute "14-2 15-2 whatever it takes" micheal keaton in mr mom.
There has been a 14-4 romex and a 12-4 romex cable available for quite some time now which is probably your most cost effective solution. It has a black conductor, a red conductor , a white conductor and a white with a red stripe conductor, and a bare ground conductor. As far as box fill goes you are going to have to treat it as two 14-2's or 12-2's.
One advantage of a multiwire circuit is voltage drop. If this is on the other end of a big house, that could be important. Both cost and voltage drop go out the window if you use a specialty item like 14-4.
I don't do this stuff often, but it is my understanding that you cannot run a 14/3 for two afci circuits and expect to share the neutral as an Edison circuit. Same with GFCI circuit breakers. You would have to run 14/4 or 12/4 providing a seperate neutral for each circuit. So what then would be the point of a 2 pole circuit breaker? Would you be planning to terminate both circuits on the same yoke? That would be the only circumstance I can think of that would need a 2 pole breaker.
It was "220, 221, whatever it takes" in response to Martin Mull's "You putting in 220?" ahhh i stand corrected. thanx larry. but i think the labor is lessend when one uses 3-wire over two..landing in panel,stapeling,running straight and pretty not twisted and such. plus its easier(imho)to run 3-wire hommies to hall outlets for some crazy reason if one must troubleshoot(who said trouble?). thats just the way i learned.
yes when i said 2 pole i ment individual trip. two afi's sharing a neut.
Bear in mind when you go over 3 current carrying conductors you start derating.
gfretwell wouldn't the neutral only count as current carrying if there were harmonic distoration present granted one could plug anything into an outlet and present this but should we anticipate this? dunno just asking...knowledge is a beautiful thing!
14-4 huh? will look into this wire a simple solution to a shared nuet.
If you use the 14 or 12/4 cables you will have two 2 wire circuits.
That is 4 current carrying conductors.
The neutral of a two wire circuit is always considered by the NEC to be a current carrying conductor.
If you ran these two circuits using a multiwire branch circuit in 12 or 14/3 from a 240/120 service you would only have two current carrying conductors as the neutral will only carry the imbalance of current between the two circuits.
Bob Badger Construction & Maintenance Electrician Massachusetts