Question 13090 of 749 · Maryland Journeyperson Electrician Exam
What is the maximum setting, under the basic table percentage, of an instantaneous trip breaker for a 10 hp, 460 volt, three-phase squirrel-cage motor with a table full-load current of 14 A?
Exactly one answer is correct.
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Correct answer to question 13090
- B: 112 A
Explanation
Instantaneous trip breakers are limited to 800 % of full-load current for these motors: 14 x 8 = 112 A. 182 A would be 1,300 %, which needs an exception, and 35 A is the 250 % inverse time value.
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