Code Q&A: Maintaining Mechanical Continuity of Sheaths and Raceways

Nov. 23, 2022

Test your knowledge of the NEC.

Based on the 2020 NEC.

Q. What are the rules for the mechanical continuity of raceways and cable sheaths?

See answer below.

A. As noted in Sec. 300.12, raceways and cable sheaths must be mechanically continuous between boxes, cabinets, and fittings.

Exception No. 1: Short sections of raceways used to provide support or protection of cables from physical damage are not required to be mechanically continuous (Sec. 250.86 Exception No. 2 and Sec. 300.10 Exception No. 1).

Exception No. 2: Raceways and cables installed into the bottom of open-bottom equipment such as switchboards, motor control centers, and floor or pad-mounted transformers are not required to be mechanically secured to the equipment.

These materials are provided to us by Mike Holt Enterprises in Leesburg, Fla. To view Code training materials offered by this company, visit www.mikeholt.com/code.

About the Author

Mike Holt

Mike Holt is the owner of Mike Holt Enterprises (www.MikeHolt.com), one of the largest electrical publishers in the United States. He earned a master's degree in the Business Administration Program (MBA) from the University of Miami. He earned his reputation as a National Electrical Code (NEC) expert by working his way up through the electrical trade. Formally a construction editor for two different trade publications, Mike started his career as an apprentice electrician and eventually became a master electrician, an electrical inspector, a contractor, and an educator. Mike has taught more than 1,000 classes on 30 different electrical-related subjects — ranging from alarm installations to exam preparation and voltage drop calculations. He continues to produce seminars, videos, books, and online training for the trade as well as contribute monthly Code content to EC&M magazine.