Branch Circuits & WiringQuestion 207 of 521
An 8 AWG THHN copper conductor (55 A at the 90°C column) is installed where the ambient temperature is 46–50°C. Using the 90°C correction factor of 0.82, what is the corrected ampacity?
a.55 A
b.50 A
c.45 A
d.41 A
Explanation
55 A × 0.82 = 45.1 A, rounded to 45 A. Using no correction (55 A) ignores the elevated ambient, and the other values apply the wrong factor.
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