Question 2025 of 844 · Washington 01 Journey Level Electrician Exam
Using the 83 percent rule of the 2020 and 2023 NEC, what minimum aluminum XHHW conductor at 75 degrees C is needed for a 200 A, 120/240 volt one-family dwelling service?
Exactly one answer is correct.
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Correct answer to question 2025
- B: 4/0 AWG
Explanation
200 A times 0.83 is 166 A. From Table 310.16, 75 degree C aluminum column, 4/0 is rated 180 A and 3/0 is only 155 A. See 310.12.
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