General Requirements for Sensitive Electronic Equipment

April 27, 2015
The provisions of Art. 647 cover the installation and wiring of separately derived systems operating at 120V line-to-line and 60V to ground for sensitive electronic equipment.

The purpose of special separately derived systems for sensitive electronic equipment is to reduce objectionable noise in sensitive electronic equipment in _____ locations.

a) commercial
b) industrial
c) a or b
d) institutional

See answer and applicable Code reference

The correct answer is: c) a or b

The provisions of Art. 647 cover the installation and wiring of separately derived systems operating at 120V line-to-line and 60V to ground for sensitive electronic equipment. As noted in condition (1) of Sec. 647.3, "The system is installed only in commercial or industrial occupancies."

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.

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