Question 13089 of 749 · Maryland Journeyperson Electrician Exam
A 30 hp, 460 volt, three-phase motor has a table full-load current of 40 A. What is the maximum nontime-delay fuse size, using the next-higher-standard-size allowance?
Exactly one answer is correct.
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Correct answer to question 13089
- A: 125 A
Explanation
Nontime-delay fuses are limited to 300 %: 40 x 3 = 120 A. 120 A is not a standard size, so the next higher standard size of 125 A is permitted.
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