Question 8061 of 731 · Texas Journeyman Electrician Exam
A transformer rated 1000 volts or less has primary protection only, and the primary current is 9 A or more. What is the maximum primary overcurrent device rating?
Exactly one answer is correct.
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Correct answer to question 8061
- A: 125 percent of rated primary current
Explanation
Table 450.3(B) limits primary-only protection to 125 percent of the rated primary current when that current is 9 A or more. If 125 percent does not match a standard size, the next higher standard size is permitted.
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