Supplementary overcurrent protection ______.
a) shall not be used in luminaires
b) may be used as a substitute for a branch-circuit overcurrent device
c) may be used to protect internal circuits of equipment
d) shall be readily accessible
See answer and applicable Code reference
The correct answer is: c) may be used to protect internal circuits of equipment
Article 240 provides the general requirements for overcurrent protection and overcurrent protective devices rated 1,000V or less, nominal. As per 240.10, "Where supplementary overcurrent protection is used for luminaires, appliances, and other equipment or for internal circuits and components of equipment, it shall not be used as a substitute for required branch-circuit overcurrent devices or in place of the required branch-circuit protection. Supplementary overcurrent devices shall not be required to be readily accessible."
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.