Which NEC section covers minimum size and ampacity of differing conductors for various reasons?

Which NEC section covers minimum size and ampacity of differing conductors for various reasons?

• A. NEC Section 220.14(A)
• B. NEC Section 230.42
• C. NEC Section 230.79
• D. NEC Section 230.42

Answer: (C)

Minimum size and ampacity rules for service- and feeder-conductors ensure the wire isn’t undersized for any installation condition. This NEC section sets the required minimum conductor sizes and their ampacity for service and feeders across different installation scenarios, tying into temperature ratings and derating so the conductors can carry the intended current safely. It provides a lower bound on conductor sizing that must be met regardless of the exact calculated load, aligning with protection devices and installation conditions. The other referenced sections focus on how loads are calculated or on different service-conductor topics, not the blanket minimum sizing rule. So the section that specifically covers minimum size and ampacity for service- and feeder-conductors is NEC 230.79.

Minimum size and ampacity rules for service- and feeder-conductors ensure the wire isn’t undersized for any installation condition. This NEC section sets the required minimum conductor sizes and their ampacity for service and feeders across different installation scenarios, tying into temperature ratings and derating so the conductors can carry the intended current safely. It provides a lower bound on conductor sizing that must be met regardless of the exact calculated load, aligning with protection devices and installation conditions. The other referenced sections focus on how loads are calculated or on different service-conductor topics, not the blanket minimum sizing rule. So the section that specifically covers minimum size and ampacity for service- and feeder-conductors is NEC 230.79.