Ecmweb 14531 6 15 17wwhlarge
Ecmweb 14531 6 15 17wwhlarge
Ecmweb 14531 6 15 17wwhlarge
Ecmweb 14531 6 15 17wwhlarge
Ecmweb 14531 6 15 17wwhlarge

What’s Wrong Here? Hint: Too Close for Comfort

June 15, 2017
Think you know how this installation violates the NEC?

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: Too close for comfort

Scroll Down to See the Answer

When sizing junction boxes or pull boxes for cables and raceways containing conductors 4 AWG and larger, Sec. 314.28 of the 2017 NEC outlines several requirements for box dimensions and raceway spacing. More specifically, 314.28(A)(1) requires the box length to be at least eight times the trade size of the largest raceway. For angle pulls, U pulls, or where the wires are spliced inside the box, 314.28(A)(2) requires the distance between the raceway  entry and the opposite wall in the box to be at least six times the trade size of the raceway. This distance then gets increased by the sum of all the other raceway entries in that row, on that same side of the box. For raceways enclosing the same conductors, the raceways must be spaced apart a distance of at least six times the larger raceway. For example, a 2-in. raceway entry would need to be spaced at least 12 in. from any other raceway containing the same conductors. As we can see in this installation, this rule was not applied by the installer that did this work. The 2-in. raceway is spaced only 4 in. apart from the 1¼-in. raceway. Boxes that are too small — and raceways that are too close — can lead to damaged conductors due to bending spaces that are too tight.

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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