What size wire and breaker is required for an air-conditioner whose nameplate specifies the circuit conductor must have a minimum rating of 44A, with overcurrent protection not to exceed 60A? The terminals on the equipment are rated 75°C.
Q. What size wire and breaker is required for an air-conditioner whose nameplate specifies the circuit conductor must have a minimum rating of 44A, with overcurrent protection not to exceed 60A? The terminals on the equipment are rated 75°C.
A. The branch-circuit conductors and short-circuit and ground-fault protection device must be sized according to the equipment’s nameplate [110.3(B)]. In this example, an 8 AWG conductor having a rating of 50A at the 75°C column of Table 310.16 [240.4(G)] protected by a 60A circuit breaker or fuse will work fine.
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.
