What's Wrong Here?

What’s Wrong Here? Hint: Hitching a Ride

Jan. 17, 2018

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Hint: Hitching a ride

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The installer of this liquidtight flexible metal conduit (LFMC) should send a “Thank You” note to the electrician who installed the rigid metal conduit (RMC) for making his job easier. Unfortunately, the authority having jurisdiction (AHJ) might be sending a note to the LFMC installer explaining that his installation is a Code violation.

Generally speaking, Sec. 300.11(C) tells us that raceways should not be used for supporting other raceways, cables or other non-electrical equipment. Using LFMC for this installation could be considered a violation of Sec. 350.10 since the need for flexibility or protection from liquids is obviously not required here. The RMC installation proves that point. The installer apparently wanted to take the easy way out. Installing another RMC or perhaps EMT or even PVC conduit would have made for a better installation.

I’m also curious how many bends are in the run of LFMC. LFMC installations must comply with Sec. 350.26 and must not have more than 360° of bends between pull points. Since the LFMC is longer than 6 ft, Sec. 250.118(6) tells us it cannot be used as an equipment grounding conductor (EGC). Hopefully, the installer included an equipment grounding wire with the circuit wires, otherwise the equipment connected to the LFMC may not be grounded and bonded properly.

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.