Code Q&A

April 9, 2009

Q. The old panels in an industrial building do not have complete panel schedules. Does the Code require us to update them?

Mike Holt

Q. The old panels in an industrial building do not have complete panel schedules. Does the Code require us to update them?

A. The circuits should have been identified when they were installed. In addition, circuits that are modified must be legibly identified as to their clear, evident, and specific purpose [408.3]. Identification must include sufficient detail to allow each circuit to be distinguished from all others, and the identification must be on a circuit directory located on the face or inside of the door of the panelboard.

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.