When connecting a main panel to a sub-panel, what is the smallest conductor size that can be run in parallel?

When connecting a main panel to a sub-panel, what is the smallest conductor size that can be run in parallel?

• A. No. 6
• B. No. 8
• C. No. 10
• D. No. 12

Answer: (A)

The smallest conductor size that can be run in parallel when connecting a main panel to a sub-panel is No. 6. This is due to the requirements set forth in the National Electrical Code (NEC) regarding ampacity and the use of conductors in parallel. When conductors are run in parallel, they must be of the same size and type to ensure balanced load sharing and to maintain safety.

Using No. 6 conductors meets the minimum ampacity requirements for typical sub-panel connections, ensuring that the wire can handle the electrical load without overheating. Smaller conductor sizes, such as No. 8, No. 10, or No. 12, may not provide sufficient current-carrying capacity for the demands typically placed on a sub-panel, which can lead to unsafe conditions such as overheating or potential failure of the wiring system.

Thus, the choice of No. 6 as the smallest conductor size for running in parallel is grounded in safety standards, electrical load considerations, and compliance with the NEC regulations, making it the correct answer in this context.