Unless specifically defined by the code, what is the maximum overcurrent protection for a 12 AWG copper conductor?

The maximum overcurrent protection for a 12 AWG copper conductor is 20 amps, as specified in the National Electrical Code (NEC). This is based on the standard calculations for ampacity and overcurrent protection.

When determining the appropriate overcurrent protection for conductors, one key principle is that the protection device should not exceed the ampacity of the conductor under its specific installation conditions. For a 12 AWG copper conductor, the typical ampacity is listed as 20 amps for general circuit applications.

This means that a circuit breaker or fuse protecting this conductor should be rated at or below 20 amps to ensure safety and compliance with electrical codes. Using a higher amperage protection could pose risks such as overheating, increased fire hazards, and insulation damage.

In scenarios where the code specifies different conditions or arrangements (like specific environmental factors or additional load requirements), adjustments could be made. However, in the absence of such specifications, sticking to the 20 amps is the established safe practice.