Is it code to use armored cable in a barn, and use plastic junction boxes? Its all open wall and ceiling,I was going to use the 12-3 armored for all the runs split the 12-3 for the lights and outlets then use two breakers for that whole run.
Where I am at (Ontario Canada), standard practice in older wooden/open frame agricultrural buildings is NMW-10 cable (AKA UF-B), and surface mount bakelite fittings. New er "closed frame" barns will have PVC conduit and fittings. The service panel is either in a "doghouse" on the outside of the barn, or in an anteroom or mechancial room sealed from where the livestock is kept.
#56220 - 09/17/0509:04 AMRe: Armored cable in the Barn?
If this is an agricultural building as described in 547.1(A) or (B), MC cable would be allowable but definitely not AC. And if MC cable were used, plastic boxes would have to meet the exceptions to 314.3, otherwise they are not permitted with metal raceways or metal-armored cables.
#56221 - 09/17/0509:36 AMRe: Armored cable in the Barn?
This barn is all wood has two horses in there own stalls, used for horses only big sliding doors, armored cable is my first choice. I dont want any rats chewing wire, is this ok? I will be in Riverside county, Ca for this job. This is the best forum for questions and answers, something you can't get at Barns and Noble book store.
#56223 - 09/17/0511:20 AMRe: Armored cable in the Barn?
Ok, looks like pvc with plastic boxes will do, the concern was stories I read about barn fires caused from metal boxes rusted from moisture with changing temperture's and animal waste the acid's speeding up the decay on metals, That would be great if there was a spray coating that could protect the armored cable like a rust proof application. Now one point I wanted to make was the armored cable if out of reach like the ceiling runs, would that exception be possible? Ok Ok OK the secrect is out. I love armored cable, but I love horses also I want to be the safest first!
#56225 - 09/17/0501:46 PMRe: Armored cable in the Barn?
547.5 Wiring Methods. (A) Wiring Systems. Types UF, NMC, copper SE cables, jacketed Type MC cable, rigid nonmetallic conduit, liquidtight flexible nonmetallic conduit, or other cables or raceways suitable for the location, with approved termination fittings, shall be the wiring methods employed. Article 398 and Article 502 wiring methods shall be permitted for areas described in 547.1(A).
I believe corrosion is the issue, notice only copper SE cable is allowed.
Notice the absence of RMC and FMC from the list.
Bob Badger Construction & Maintenance Electrician Massachusetts