CalculationsQuestion 27 of 110
A #3 Cu THHN conductor has a 90 C ampacity of 110 A. In a 50 C ambient (correction factor 0.82), what is the corrected ampacity?
a.110 A
b.100 A
c.90 A
d.82 A
Explanation
Corrected ampacity = 110 A x 0.82 = 90.2 A, about 90 A, before comparing to the termination temperature limit.
Law Reference: 2023 NEC Table 310.15(B)(1)Practice all 110 questions free — no signup required.
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