Question 13087 of 749 · Maryland Journeyperson Electrician Exam
A 15 hp, 460 volt, three-phase squirrel-cage motor (not Design B energy efficient) has a table full-load current of 21 A. Using an inverse time breaker at its maximum percentage and the next-higher-size allowance, what breaker may be used?
Exactly one answer is correct.
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Correct answer to question 13087
- C: 60 A
Explanation
The maximum for an inverse time breaker is 250 % of full-load current: 21 x 2.5 = 52.5 A. Since 52.5 A is not a standard size, the next higher standard size, 60 A, is permitted.
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