Based on the 2020 NEC.
True or False?
Question: Branch-circuit conductors serving a single air conditioning compressor are required to be sized not smaller than the branch-circuit selection current.
See answer below.
Answer: False
Explanation: The branch-circuit conductors are required to be sized at a minimum of 125% of either the motor-compressor rated-load current or the branch-circuit selection current, whichever is greater. In the 2020 NEC, Sec. 440.32 was revised to make it clear that the 125% applied to both motor-compressor rated-load current and the branch-circuit selection current not just the motor-compressor rated-load current.
Lupacchino is a senior design engineer with Gaylor Electric, Inc. in Noblesville, Ind. and serves as an alternate on NEC Code-Making Panel No. 3. He is currently licensed in more than 80 jurisdictions. He can be reached at [email protected].
About the Author
John Lupacchino
Senior Design Engineer
John began his career in electrical construction as an apprentice and worked his way through the trade. He is currently licensed in more than 80 jurisdictions. With more than 35 years of experience, he now plays a vital role in Gaylor Electric’s Engineering Department, where he serves as a senior design engineer. With a focus on design engineering, quality assurance, and code compliance, he has earned the highest level of respect from industry professionals alike. John currently serves as an alternate on NFPA 70 Code Making Panel No. 3. In addition, he enjoys sharing his electrical knowledge through education. As an Associated Builders and Contractors instructor, he continues to help grow a new generation of high-performing construction leaders.