National Electrical Code

Code Q&A

Jan. 7, 2005

Q. Does the Code permit a circuit breaker to be installed horizontally? A. Enclosures that contain overcurrent protection devices must be mounted in a vertical position unless this isn’t practical (240.33). However, where circuit breaker handles are ...

Mike Holt

Q. Does the Code permit a circuit breaker to be installed horizontally?

A. Enclosures that contain overcurrent protection devices must be mounted in a vertical position unless this isn’t practical (240.33). However, where circuit breaker handles are operated vertically, the “up” position of the handle must be in the “on” position (240.81). So in effect, an enclosure that contains one circuit breaker can be mounted horizontally, but an enclosure that contains a panelboard/load center with multiple circuit breakers would have to be mounted vertically.

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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.