Journeyman Electrician Practice Exam

What is the minimum size branch circuit conductors for a 50-ampere rated circuit based on NEC®?

1. 10 amperes

2. 15 amperes

3. 20 amperes

4. 30 amperes

The correct answer is: 15 amperes

The minimum size branch circuit conductors for a 50-ampere rated circuit according to the National Electrical Code (NEC) can be determined by looking at the NEC guidelines that specify conductor sizing based on the ampacity tables. For a 50-ampere circuit, the NEC typically requires the use of conductors that can safely handle the full load current. Based on the requirements found in NEC Table 310.16, a 50-ampere circuit would generally necessitate conductors that are sized appropriately to ensure safety and prevent overheating. The most common conductor sizes that can handle a 50-amp load are typically 6 AWG copper or 4 AWG aluminum conductors. While 15 amperes refers to the ampacity of smaller circuits for lighting and receptacles, it does not meet the necessary capacity for a circuit designed to handle 50 amperes. This ensures that the conductors used can adequately support the intended load without risk of damage or failure due to overheating. Thus, for a 50-ampere rated circuit, it is essential to use conductors that are rated accordingly, and the choice related to 15 amperes does not satisfy the requirements of such a circuit. Rather, the standards and safety