What is the maximum overcurrent protection rating for 12 AWG THHN conductors on a 20-ampere receptacle?

The maximum overcurrent protection rating for 12 AWG THHN conductors in the context of a 20-ampere receptacle is 20 A. This is based on the National Electrical Code (NEC), which provides guidelines for safe electrical installations.

12 AWG THHN conductors are rated for a maximum of 20 amps for continuous use. Thus, this means that the current flowing through these conductors should not exceed 20 A under normal operating conditions. Choosing a circuit breaker or fuse that matches this rating is essential to ensure the conductors are protected against overcurrent, which could lead to overheating and potential fire hazards.

By adhering to this rating, the installation remains safe while allowing for the necessary operational capacity of a 20-ampere receptacle. Ensuring that the overcurrent protection matches the wire gauge and application is vital to maintaining compliance with safety standards. Therefore, 20 A is the correct answer as it aligns with safe practices for wiring installations.