Question 8062 of 790 · California General Electrician Exam
A small control transformer has a primary current of 5 A and primary protection only. What is the maximum primary overcurrent device rating?
Exactly one answer is correct.
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Correct answer to question 8062
- A: 167 percent of rated primary current
Explanation
Table 450.3(B) allows 167 percent for primary currents less than 9 A but 2 A or more, when only primary protection is provided. Small transformers have relatively high magnetizing inrush.
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