Code Q&A

Q. Can Table 310.15(B)(6) be used to size service conductors to a duplex, where there is no firewall separating the units? A. No. Table 310.15(B)(6) only allows a reduced-size service and feeder conductors for individual dwelling units of one-family, ...

Mike Holt

Dec. 11, 2006

Q. Can Table 310.15(B)(6) be used to size service conductors to a duplex, where there is no firewall separating the units?

A. No. Table 310.15(B)(6) only allows a reduced-size service and feeder conductors for individual dwelling units of one-family, two-family, and multi-family dwellings meeting the requirements of 310.15(B)(6). However, the main power feeder conductors to each dwelling unit can be sized using Table 310.15(B)(6).

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.