Branch Circuits & FeedersQuestion 21 of 120
For that same 45-ampere continuous lighting feeder, what is the minimum copper conductor size at 75 degrees C terminations?
a.6 AWG
b.8 AWG
c.4 AWG
d.10 AWG
Explanation
The conductor must carry 45 x 1.25 = 56.25 A. In the 75 degrees C column, 8 AWG copper is 50 A and is insufficient, while 6 AWG copper at 65 A meets the requirement. 4 AWG is oversized for the stated minimum, and 10 AWG at 35 A is far below the calculated ampacity.
Law Reference: 2023 NEC §215.2(A)(1)Practice all 120 questions free — no signup required.
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