12:25PM | 01/08/03
Member Since: 01/05/03
5 lifetime posts
I'm having trouble understanding a section of the NEC. It's the part that states that non-metallic cables bundled together for more than 24" need to be downrated. I don't want to downrate the cables but I also I want to drill the minimum number of holes in my studs that is necessary for running several cables in a wall. Does anyone know how far apart the cables need to be before they're not considered bundled? I would like to run three cables through each hole and then somehow separate them the required distance between studs.

Thanks in advance!

Tom O

11:27AM | 01/09/03
Member Since: 09/17/02
487 lifetime posts
You will not have to worry about derating 3 cables if they are bundled, provided that you are dealing with single phase power (what almost all homes have).

Three each two wire cables results in 6 current carrying conductors and their ampacity is still 20 amps or more.

Three each 3 wire cables, run as multi-wire circuits still only have 6 current carrying conductors You don't count the neutrals in this case, but even if you did, the final ampacity is still 20 amps or more.

None of this takes temperature into account.



08:00AM | 01/10/03
Member Since: 01/05/03
5 lifetime posts
Ah, I see now. I'm slowly figuring this out. Thanks for all the info, Tom. I'll keep in mind that I still need to consider temp and voltage drop.

So it looks like I'll be able to bundle four cables (8 current carrying conductors) together and still be above the max ampacities for 14AWG and 12AWG (what I'm using). But I'll still have 2 bundles of four that will need to run parallel for more than 2 feet. How far apart should these two bundles be?



Post a reply as Anonymous

Photo must be in JPG, GIF or PNG format and less than 5MB.


type the code from the image


Post_new_button or Login_button

Deep blue grays like the shade shown in this example "have a nautical, serene feeling," says Amy Hendel, designer for Hend... Built on a rocky island in the Drina River, near the town of Bajina Basta, Serbia, this wooden house was cobbled together ... Large steel-framed windows flood the interior of this remodeled Michigan barn with daylight. The owners hired Northworks A... Edging formed with upside-down wine bottles is a refreshing change. Cleverly and artistically involving recycled materials... A Washington State couple called on BC&J Architects to transform their 400-square-foot boathouse into a hub for family bea... Similar to the elevated utensil concept, hanging your pots and pans from a ceiling-mounted rack keeps them nearby and easy... Few projects are more fun than upcycling a vintage piece in a surprising way. Outfitted with a sink and a delicately tiled... The thyme growing between these stepping stones adds a heady fragrance to strolls along this lush, low-maintenance garden ... Decoupage is an easy way to add any paper design to your switch plate, whether it is wallpaper, scrapbook paper, book page... Twine lanterns add pops of crafty—but sophisticated—flair to any outdoor setting. Wrap glue-soaked twine around a balloon ... When securely fastened to a tree or the ceiling of a porch, a pallet and some cushioning make the ideal place to lounge. V... Reluctant to throw away any of those unidentified keys in your junk drawer? Hang them from a few chains attached to a simp... A stripped-down model, sans screened porch, starts out at $79,000. Add the porch, a heated floor for the bath, and all the... Salvaged boards in varying widths and colors make up the dramatic accent wall in this attic space. The high-gloss white of... This garden shed has been decked out to the nines. Designer Orla Kiely created the intimate home for a flower trade show, ...
Newsletter_icon Google_plus Facebook Twitter Pinterest Youtube Rss_icon