Ecmweb 12981 Nec Illustrated Catastrophes Pr
Ecmweb 12981 Nec Illustrated Catastrophes Pr
Ecmweb 12981 Nec Illustrated Catastrophes Pr
Ecmweb 12981 Nec Illustrated Catastrophes Pr
Ecmweb 12981 Nec Illustrated Catastrophes Pr

Illustrated Catastrophes: Getting a Leg Up on the Competition

March 20, 2017
More Code catastrophes uncovered and corrected in these faulty installations

All references are based on the 2017 edition of the NEC.

Getting a Leg Up on the Competition

That is one way to get the job done quickly. Of course, it’s not done correctly. I am having a hard time imagining how the installer was able to install the wires in this EMT, unless the raceway was piecemealed together in order to accommodate the wire pull. If this was the case, then it would have been a violation of Sec. 300.18, which requires raceways to be installed complete before installing the conductors. Section 410.30(B)(1) requires the handhole and its cover on this metal pole to be able to provide access to the supply conductors. I don’t know how that is possible now unless you disassemble or dig up the EMT. Bending the EMT out of the way in order to access the handhole would most likely kink it or cause other irreparable damage. Perhaps the installer would have been better off running the EMT around the other side of the pole and installing the EMT or maybe a flexible wiring method into the pole opposite the handhole cover. I also question the effective electrical continuity of the bonding and grounding connections established by connecting the EMT to the handhole cover. I would say this violates the intent of Sec. 300.10.

Pandora’s Box

I discovered this gem while troubleshooting the power and control systems for some air conditioning units. First, I will point out the misuse of the PVC junction box as a panelboard enclosure. This is a violation of Sec. 110.3(B). On the upper left side, the lack of bending space for the 6 AWG wires exiting the circuit breaker terminals violates the intent of Sec. 312.6(B)(1) and Table 312.6(A), which requires at least 1½ in. of bending space for these copper wires. On the bottom of the enclosure there are low-voltage Class 2 control circuit cables and conductors mixed in with the power conductors. Section 725.136(A) does not permit Class 2 circuits to be in any enclosure, device box, outlet box, raceway or similar fitting with power conductors unless permitted by Sec. 725.136(B) through (I). There are no barriers to separate the circuits as required by Sec. 725.136(B). In addition, the Class 2 circuits were not installed inside a raceway within the enclosure as permitted by Sec. 725.136(C). Section 725.136(D) allows the circuits to be installed in the same enclosure where separated by 0.25 in. or greater, but this section is not applicable, since the Class 2 circuits are not connected to any associated equipment in the enclosure — they simply pass through this enclosure. None of the other rules in Sec. 725.136(E) through (I) are applicable to this installation.

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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