Question 13047 of 731 · Texas Journeyman Electrician Exam
Six current-carrying 10 AWG THHN copper conductors share one raceway at 30 °C ambient. What is the adjusted ampacity from the 90 °C column?
Exactly one answer is correct.
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Correct answer to question 13047
- C: 32 A
Explanation
The 90 °C ampacity of 10 AWG copper is 40 A, and 4 to 6 current-carrying conductors require an 80 % adjustment: 40 x 0.80 = 32 A. The 70 % factor (28 A) applies to 7 to 9 conductors.
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