Question: Under which of the following conditions would a run of electrical metallic tubing (EMT) with compression fittings require an equipment grounding conductor (EGC) to be installed with the circuit conductors?
- EMT installed along a bar joist supplying high-bay luminaires in a warehouse
- EMT installed within a metal stud wall supplying receptacles
- EMT installed outdoors on a roof supplying a roof top HVAC unit
- EMT installed on the surface of a masonry wall
See the answer below.
Answer: C. EMT installed outdoors on a roof supplying a roof top HVAC unit
Explanation: The 2017 NEC added Sec. 440.9, which requires outdoor portions of metal raceways installed on a roof supplying multi-motor and combination-load equipment to contain a wire type EGC unless the metal raceway utilizes threaded fittings. This requirement is intended to maintain the continuity of the equipment grounding path in the event the EMT becomes separated at a non-threaded fitting.
Lupacchino is a senior design engineer with Gaylor Electric, Inc. in Noblesville, Ind. and serves as an alternate on NEC Code-Making Panel No. 3. He is currently licensed in more than 80 jurisdictions. He can be reached at [email protected].
About the Author
John Lupacchino
Senior Design Engineer
John began his career in electrical construction as an apprentice and worked his way through the trade. He is currently licensed in more than 80 jurisdictions. With more than 35 years of experience, he now plays a vital role in Gaylor Electric’s Engineering Department, where he serves as a senior design engineer. With a focus on design engineering, quality assurance, and code compliance, he has earned the highest level of respect from industry professionals alike. John currently serves as an alternate on NFPA 70 Code Making Panel No. 3. In addition, he enjoys sharing his electrical knowledge through education. As an Associated Builders and Contractors instructor, he continues to help grow a new generation of high-performing construction leaders.