Question 8065 of 749 · Maryland Journeyperson Electrician Exam
With primary and secondary protection, what is the maximum secondary device rating for a transformer with a secondary current of 9 A or more?
Exactly one answer is correct.
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Correct answer to question 8065
- B: 125 percent of rated secondary current
Explanation
Table 450.3(B) limits secondary protection to 125 percent of rated secondary current when that current is 9 A or more, with the next higher standard size permitted. For secondary currents below 9 A the limit is 167 percent.
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