If a set of 120/240V overhead feeder conductors terminates at a through-the-roof raceway or approved support, with less than 6 ft of these conductors passing over the roof overhang, the minimum clearance above the roof for these conductors is _____.
a) 12 in.
b) 18 in.
c) 2 ft
d) 5 ft
See answer and applicable Code reference
The correct answer is: b) 18 in.
Article 225 covers requirements for outside branch circuits and feeders. Section 225.19 outlines the clearance requirements from buildings for conductors 600V and less, nominal. As per 225.19(A), Exception No. 3, "Where the voltage between conductors does not exceed 300, a reduction in clearance above only the overhanging portion of the roof to not less than 18 in. shall be permitted if more than 6 ft of the conductors, 4 ft horizontally, pass above the roof overhang and they are terminated at a through-the-roof raceway or approved support."
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.