National Electrical Code

Services and Feeders for Mobile and Manufactured Homes

Sept. 4, 2018

Part II of Art. 550 in the 2017 NEC provides the requirements for the power supply to these structures

Part II of Art. 550 in the 2017 Edition of the National Electrical Code (NEC) provides the requirements for the power supply to these structures. Services and feeders to them are covered separately in Part III of Art. 550.

One requirement is the mobile home park secondary electrical system to mobile home lots must be single-phase, 120/240V [Sec. 550.30]. So, home service equipment is going to be for that type of distribution. And the service must be rated at least 100A [Sec. 550.32(C)].

Service equipment cannot be mounted on or in a mobile home [Sec. 550.32(A)], but it can be mounted on or in a manufactured home if the conditions of Sec. 550.32(B)(1) through (7) are met.

What if you have a car port or little tool shed to supply power to? You must use a fixed wiring method in either the service equipment or the local external disconnecting means that Sec. 550.32(A) permits [Sec. 550.32(D)]. You can’t run it from the breaker panel inside the unit.

Feeder conductor installation must comply with Sec. 250.32B (one exception is noted) [Sec. 550.33]. Feeder capacity must be at least equal to the loads supplied [Sec. 550.33(B)].

About the Author

Mark Lamendola

Mark is an expert in maintenance management, having racked up an impressive track record during his time working in the field. He also has extensive knowledge of, and practical expertise with, the National Electrical Code (NEC). Through his consulting business, he provides articles and training materials on electrical topics, specializing in making difficult subjects easy to understand and focusing on the practical aspects of electrical work.

Prior to starting his own business, Mark served as the Technical Editor on EC&M for six years, worked three years in nuclear maintenance, six years as a contract project engineer/project manager, three years as a systems engineer, and three years in plant maintenance management.

Mark earned an AAS degree from Rock Valley College, a BSEET from Columbia Pacific University, and an MBA from Lake Erie College. He’s also completed several related certifications over the years and even was formerly licensed as a Master Electrician. He is a Senior Member of the IEEE and past Chairman of the Kansas City Chapters of both the IEEE and the IEEE Computer Society. Mark also served as the program director for, a board member of, and webmaster of, the Midwest Chapter of the 7x24 Exchange. He has also held memberships with the following organizations: NETA, NFPA, International Association of Webmasters, and Institute of Certified Professional Managers.