Illustrated Catastrophes: A Whole-Lotta-Wrong

April 20, 2015

More Code catastrophes uncovered and corrected in these faulty installations

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A Whole-Lotta-Wrong

I’m not quite sure where to begin with this one because there is so much wrong. Perhaps the most dangerous violation is the way in which the MC cable is wired into this box. In violation of Sec. 330.30(A), the cable jacket was not cut cleanly and was just peeled back, leaving jagged metal edges in contact with the conductors. This could easily damage the insulation and cause a short circuit. The lack of a connector on the cable is also dangerous because there is no electrical continuity established between the metal box and the metal cable jacket. This lack of continuity is a violation of Sec. 300.10.

The use of EMT to support the box violates Sec. 358.12(5). Similarly, Sec. 314.23(E) has been violated because that section requires the use of conduit threaded wrenchtight into threaded entries or special hubs when supporting a box with a raceway. The misuse of a cable tie to support the EMT raceway is a violation of Sec. 110.3(B). Even its name indicates that “cable tie” is not the correct supporting means for a “raceway.”

Lastly is the lackadaisical way in which the installer attempted to install a cover on the box, violating the intent of Sec. 314.25 in the process.

Hickory, Dickory, Dock...

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This poor mouse had no idea of the danger lurking inside this time clock enclosure. I found him wedged behind the removable clock motor insert while I was on an emergency call troubleshooting the reason why some parking lot lights were not working. Needless to say, I found the problem.

The circuit breaker tripped when this poor guy came into contact with the energized contacts on the back of the time clock. He stood no chance of surviving. The reason he was able to get inside this enclosure was because one of the knockouts was missing and never closed up — a clear violation of the requirements of Sec. 110.12(A). It also created some safety concerns when the circuit breaker tripped, which plunged the busy parking lot into complete darkness. Thankfully, the presence of the mouse and the short circuit he caused did not lead to a worse situation, such as a fire caused by arcing and sparking.

In accordance with Sec. 110.12(B), I needed to replace the time clock because it was damaged. The installation of a simple and inexpensive knockout seal could have prevented this entire situation from happening in the first place.

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.