Based on the 2026 NEC.
Question: What is required when rigid metal conduit enters an enclosure through an opening that is not threaded?
See answer below.
Answer: A locknut or fitting must be installed on the inside and outside of the enclosure.
Reference: Section 344.29
Explanation: Section 344.29 was added to explicitly require the conduit to be secured on both sides of the enclosure by locknuts or a fitting and a locknut. This ensures compliance with Sections 300.12 and 300.14. The same requirements was also added as Sec. 342.29 for intermediate metal conduit.
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.