A residential service panel has a 200A main disconnect. What is the minimum size of the overcurrent protection required for a 120V, 20A branch circuit?
- 15A
- B20A
- C30A
- D40A
Exam tip
When selecting overcurrent protection, ensure it does not exceed 125% of the branch circuit rating, as per NEC Article 210.11(A).
Why A is correct
According to 2026 NEC Article 210.11(A), the overcurrent protection for a 120V, 20A branch circuit must not exceed 125% of the branch circuit rating. In this case, 20A x 1.25 = 25A. The 15A breaker is the minimum size that meets this requirement. The other options are incorrect as they exceed the allowable overcurrent protection size.