Question 2049 of 790 · California General Electrician Exam
Using the 83 percent rule of the 2020 and 2023 NEC, what minimum copper THWN 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 2049
- A: 2/0 AWG
Explanation
200 A times 0.83 is 166 A. From Table 310.16, 75 degree C column, 2/0 copper is rated 175 A and 1/0 is only 150 A. See 310.12.
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