What is the minimum size for conductors used in overhead service drops?

The minimum size for conductors used in overhead service drops must be determined based on the ampacity as outlined in NEC tables. This is crucial because the appropriate conductor size directly relates to the amount of current it needs to carry, and several factors—including the type of conductor material (copper or aluminum), temperature rating, and installation conditions—affect the conductor's ampacity.

The NEC provides specific tables that detail the maximum current-carrying capacity for various sizes and types of conductors. Therefore, rather than adhering to a single minimum size regardless of conditions, it is essential to consult these ampacity tables to ensure that the conductor can safely handle the expected load without exceeding its rated capacity. This approach not only ensures safety and compliance with the code but also minimizes the risk of overheating and potential electrical failures.

In contrast, the other options suggest fixed sizes without consideration of the specific context or load requirements, which does not align with the NEC philosophy of ensuring safety through proper sizing based on actual conditions.