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Maintenance, Repair & Operations

The NEC and Fire Alarm Systems — Part 2

Nov. 17, 2020

Highlights of Art. 760, Part II

Part II of Art. 760 of the National Electrical Code provides the requirements for non-power-limited fire alarm (NPLFA) circuits. Some highlights include:

The power sources must comply with Chapters 1 through 4 [760.41(A)].
Output voltage cannot exceed 600V.
The disconnect can be secured in the “ON” position.
The branch circuit cannot supply other loads [760.41(B)].
For conductors 14 AWG and larger, do not apply ampacity adjustment and correction factors when sizing the overcurrent protection [760.43].
The ampacity adjustment factors of 310.15(C)(1), however, apply to conductors in raceway for each conductor that continuously carries over 10% of its ampacity [760.51(A)].
As with other kinds of circuits, locate the overcurrent protection where the conductor receives its supply. However, there are three exceptions listed in 760.45. For example, when the OCPD protecting the larger conductor also protects the smaller conductor.
If you put NPFLA conductors in the same raceway as Class 1 power supply conductors, then all conductors must be insulated for the maximum voltage of any conductor in that raceway [760.48(A)].
You can use only copper conductors [760.49(A)].

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.