Question 13057 of 749 · Maryland Journeyperson Electrician Exam
What is the allowable ampacity of 4/0 AWG XHHW aluminum conductors in the 75 °C column at 30 °C ambient with not more than three current-carrying conductors?
Exactly one answer is correct.
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Correct answer to question 13057
- A: 180 A
Explanation
Table 310.16 lists 180 A for 4/0 aluminum in the 75 °C column. 230 A is the copper value, 205 A is the aluminum 90 °C value and 150 A is the aluminum 60 °C value.
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