Ecmweb 3251 12 18 08codeqaweb
Ecmweb 3251 12 18 08codeqaweb
Ecmweb 3251 12 18 08codeqaweb
Ecmweb 3251 12 18 08codeqaweb
Ecmweb 3251 12 18 08codeqaweb

Code Q&A

Dec. 18, 2008
Can a junction box contain both 277V and 120V conductors?

Q. Can a junction box contain both 277V and 120V conductors?

A. Yes, providing all conductors have an insulation voltage rating not less than the maximum circuit voltage (277V) [300.3(C)].

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.

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