Question 8012 of 749 · Maryland Journeyperson Electrician Exam
What is the maximum rating of a dual-element time-delay fuse used as motor branch-circuit short-circuit and ground-fault protection?
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Correct answer to question 8012
- B: 175 percent of full-load current
Explanation
Table 430.52 allows dual-element (time-delay) fuses up to 175 percent of the table full-load current for common ac motors. Their time delay carries starting current, so a lower percentage is needed than for nontime delay fuses.
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