Code Quiz of Day

Marking Requirements for Circuit Breakers Used as Switches

March 5, 2015

Parts I through VII of Art. 240 provide the general requirements for overcurrent protection and overcurrent protective devices not more than 1,000V, nominal.

Mike Holt

Circuit breakers used to switch 120V or 277V fluorescent lighting circuits shall be listed and marked _____.

a) UL
b) SWD or HID
c) Amps
d) VA

See answer and applicable Code reference

The correct answer is: b) SWD or HID

Article 240 outlines the requirements for overcurrent protection. Parts I through VII of this Article provide the general requirements for overcurrent protection and overcurrent protective devices not more than 1,000V, nominal. As noted in Sec. 240.83(D), "Circuit breakers used as switches in 120V and 277V fluoresecent lighting circuits shall be listed and shall be marked SWD or HID. Circuit breakers used as switches in high-intensity discharge lighting circuits shall be listed and shall be marked as HID."

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.