What gauge is used in conduit number 2 in the described arrangement?

What gauge is used in conduit number 2 in the described arrangement?

• A. 8 AWG
• B. 6 AWG
• C. 10 AWG
• D. 12 AWG

Answer: (B)

The key idea here is sizing conductors by their ampacity and the insulation rating, not by the conduit alone. For a circuit that requires 60 A, you pick a conductor that can safely carry at least that much current. Copper conductors with THHN insulation rated for 75°C have higher ampacities. A #6 copper THHN is typically about 65 A at 75°C, which covers a 60 A load. Smaller sizes, like #8, are only in the 40–50 A range and would be undersized for a 60 A circuit. Larger sizes aren’t needed unless you’re accounting for voltage drop over a long run or other derating factors. So, in this arrangement, #6 AWG copper is the appropriate gauge for the 60 A circuit in that conduit, balancing the required ampacity with the typical fill considerations.

The key idea here is sizing conductors by their ampacity and the insulation rating, not by the conduit alone. For a circuit that requires 60 A, you pick a conductor that can safely carry at least that much current.

Copper conductors with THHN insulation rated for 75°C have higher ampacities. A #6 copper THHN is typically about 65 A at 75°C, which covers a 60 A load. Smaller sizes, like #8, are only in the 40–50 A range and would be undersized for a 60 A circuit. Larger sizes aren’t needed unless you’re accounting for voltage drop over a long run or other derating factors.

So, in this arrangement, #6 AWG copper is the appropriate gauge for the 60 A circuit in that conduit, balancing the required ampacity with the typical fill considerations.