Breaker and Wire Size Incompatibility

Wire gauge must not be undersized compared to the amperage a breaker is capable of. This could lead to overheating or failure of the wire, possibly creating fire and shock hazards. The list below shows the minimum wire size required to be provided for a fuse or circuit breaker according to NEC 240:

• 14 gauge - 15 Amps
• 12 gauge - 20 Amps
• 10 gauge - 30 Amps