Ecmweb 8350 8 4 16wwhlarge
Ecmweb 8350 8 4 16wwhlarge
Ecmweb 8350 8 4 16wwhlarge
Ecmweb 8350 8 4 16wwhlarge
Ecmweb 8350 8 4 16wwhlarge

What’s Wrong Here? Hint: Fire Sale

Aug. 4, 2016
NEC rules on support for NM cables

How well do you know the Code? Think you can spot violations the original installer either ignored or couldn't identify? Here's your chance to moonlight as an electrical inspector and second-guess someone else's work from the safety of your living room or office. It's your turn to identify the violation.

Hint: Fire sale

Find the Answer

I spotted this installation while visiting a store. Who needs boxes when you can simply make splices in free air and just wrap them with tape? Well that’s what this installer must have been asking himself.

The splices for this dangling NM cable were made without a box as required by Sec. 300.15. Even if this was a temporary installation as covered by Art. 590, a box would still be required. Section 590.4(G) permits temporary splices to be made without using a box only if the work was done at a construction site. This work was completed inside a store, which was not under construction. Therefore, the requirements of Sec. 590.4(G) are not applicable. Section 300.15 would still be applicable because 590.2(A) states that all other rules for permanent wiring shall apply to temporary wiring.

The lack of proper support for theses cables is another problem. Section 334.30 requires NM cable to be supported within 12 in. of boxes and also every 4½ ft. Section 320.30(B) requires the AC cable to be supported in the same manner. These cables were just draped across this sprinkler pipe and run throughout the store.

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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