nm cables installed in box at campground

What’s Wrong Here? Hint: Naughty NM Cable Installation

July 13, 2023
Think you know how this installation violates the NEC?

Hint: Naughty NM cable installation

I spotted this uncovered box while camping at a campground in New England. Upon closer examination, I realized that the cables pulled through this box and raceways are actually NM cables. Installing NM cables in wet locations such as these aboveground raceways is prohibited by Sec. 334.12(B)(4). These two rigid PVC conduits continued down the side of the building and into the ground where they run underground and then emerge nearby to feed some receptacle outlets. Using NM cables for an underground installation is not specifically prohibited by Sec. 334.12, however, since the Art. 100 definition of wet location includes underground locations, NM cables are not permitted to be installed underground. The lack of a box cover violates Sec. 314.25. Neither conduit complies with Sec. 300.12 since they are not continuous between the boxes at each end of the raceways.

About the Author

Russ LeBlanc | Owner

Russ started in the electrical trade as an apprentice in 1985. He worked his way up to become a Journeyman Electrician and then eventually became a Master Electrician and Licensed Construction Supervisor. In 1999 Russ become an Electrical Instructor for The Peterson School of Engineering in Massachusetts where he developed his passion for teaching, and quickly became Department Head of Electrical Instruction. Russ has taught thousands of apprentices, electricians, engineers, inspectors, and other electrical professionals during his career as an instructor. He continues to provide electrical professionals with Electrical Code seminars, Arc-Flash Awareness training seminars and educational material through his LeBlanc Consulting Services in North Reading, MA whose specialty is educating electricians. He has been an active member of the NFPA Electrical Section and has authored hundreds of National Electrical Code proposals and comments which have become Code rules to improve the safety for the electrical industry. Russ is also an IAEI certified Electrical Inspector.

Please visit www.russleblanc.net for more information.

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