The largest 2-pole circuit breaker that can be used to protect a 12 AWG copper Type SJO flexible cord serving a single-phase load is ___ A.

The largest 2-pole circuit breaker that can be used to protect a 12 AWG copper Type SJO flexible cord serving a single-phase load is ___ A.

• A. 35
• B. 25
• C. 15
• D. 20

Answer: (B)

Sizing overcurrent protection for a flexible cord follows the rule: the device must not exceed the cord’s ampacity. For a 12 AWG copper Type SJO flexible cord, the insulation and construction are rated high enough that the ampacity is 25 A. So, on a single-phase circuit, the two-pole breaker can be up to 25 A without risking overheating the cord. A larger breaker would exceed the cord’s ampacity and potentially overheat it; a smaller one would be more protective but not the largest allowable. Therefore, 25 A is the correct maximum.

Sizing overcurrent protection for a flexible cord follows the rule: the device must not exceed the cord’s ampacity. For a 12 AWG copper Type SJO flexible cord, the insulation and construction are rated high enough that the ampacity is 25 A. So, on a single-phase circuit, the two-pole breaker can be up to 25 A without risking overheating the cord. A larger breaker would exceed the cord’s ampacity and potentially overheat it; a smaller one would be more protective but not the largest allowable. Therefore, 25 A is the correct maximum.