Code Q&A: Tap Conductor Rules in Dwelling Units

May 21, 2015

NEC guidelines for tap conductors on cooking units

Q. What are the tap conductor requirements to supply household ranges, wall-mounted ovens, and counter-mounted cooking units?

Find the Answer

A. Branch circuit conductors that supply household ranges, wall-mounted ovens, or counter-mounted cooking units must have an ampacity not less than the rating of the branch circuit — and not less than the maximum load to be served. For ranges of 8¾ kW or more, the minimum branch circuit ampere rating is 40A [210.19(A)(3)].

Exception No. 1: Conductors tapped from a 50A branch circuit for electric ranges, wall-mounted electric ovens, and counter-mounted electric cooking units must have an ampacity not less than 20A, and must have sufficient ampacity for the load to be served. The taps must not be longer than necessary for servicing the appliances.

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.