Code Quiz of Day

Storage Batteries Used for Emergency Power

Dec. 11, 2014

Article 700 focuses on the installation, operation and maintenance of emergency systems.

A storage battery supplying emergency lighting and power shall maintain not less than 87½% of normal voltage at total load for a period of at least _____ hour(s).

a) 1
b) 1½
c) 2
d) 2½

See answer and applicable Code reference

The correct answer is: b) 1½

Article 700 focuses on the installation, operation and maintenance of emergency systems. As noted in the first sentence of Sec. 700.12(A), "Storage batteries used as a source of power for emergency systems shall be of suitable rating and capacity to supply and maintain the total load for a minimum of 1½ hours, without the voltage applied to the load falling below 87½% of normal."

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.