Temp Rating of 12/2 NM-B Romex
#1
03-11-05, 12:54 PM
Temp Rating of 12/2 NM-B Romex
I installed three recessed can lites in the ceiling of my basement finishing project. I followed all wrtten instructions which wasn't much and just as I put the finishing touches on my installation I noticed some instructions stamped on the junction box cover. Wording said "Maximum of 8 No 12 AWG through brach circuit conductors suitable for at least 90 degrees C permitted in a box, (4 in, 4 out) for flexible conduit only. What does this mean and does 12/2 NM-B Romex meet requirements? Do I need to run conductors in flexible metal conduit?
For my installation I ran 12/2 to the first can lite, from there I paralleled 12/2 to the second can lite. From the second can lite I paralleled 12/2 to the third lite. Everthing works, just want to know if it's safe. BTW no insullation within 12" of cans.
Thanks for the help
For my installation I ran 12/2 to the first can lite, from there I paralleled 12/2 to the second can lite. From the second can lite I paralleled 12/2 to the third lite. Everthing works, just want to know if it's safe. BTW no insullation within 12" of cans.
Thanks for the help
#2
03-11-05, 12:55 PM
Originally Posted by Jwichman
I installed three recessed can lites in the ceiling of my basement finishing project. I followed all wrtten instructions which wasn't much and just as I put the finishing touches on my installation I noticed some instructions stamped on the junction box cover. Wording said "Maximum of 8 No 12 AWG through brach circuit conductors suitable for at least 90 degrees C permitted in a box, (4 in, 4 out) for flexible conduit only. What does this mean and does 12/2 NM-B Romex meet requirements? Do I need to run conductors in flexible metal conduit?
For my installation I ran 12/2 to the first can lite, from there I paralleled 12/2 to the second can lite. From the second can lite I paralleled 12/2 to the third lite. Everthing works, just want to know if it's safe. BTW no insullation within 12" of cans.
Thanks for the help
For my installation I ran 12/2 to the first can lite, from there I paralleled 12/2 to the second can lite. From the second can lite I paralleled 12/2 to the third lite. Everthing works, just want to know if it's safe. BTW no insullation within 12" of cans.
Thanks for the help
#3
03-11-05, 01:01 PM
They seem to be requiring metal clad flex conduit (NEC type "MC"). I assume this is so the plastic outer sheath on NM cable doesn't melt. (?) I haven't seen any problem with it, and it is my opinion that lighting manufacturers have begun in recent years to allow lawyers and liability insurers to write their instruction manuals. Hi wattage (100 or above) incandescents can produce an awful lot of heat. Halogen bulbs are also very hot. I can't exactly say that the heat will be a problem if you connected directly with NM cable.
At any rate, they do not permit more than 4 in and 4 out, and it seems like you have only 2 in and 2 out, so you're OK there. Also, modern NM-B cable is 90 degrees C. So you're OK there too.
Juice
At any rate, they do not permit more than 4 in and 4 out, and it seems like you have only 2 in and 2 out, so you're OK there. Also, modern NM-B cable is 90 degrees C. So you're OK there too.
Juice
