Question 13121 of 749 · Maryland Journeyperson Electrician Exam
Three-phase 460 volt motors are rated 5 hp (7.6 A) and 3 hp (4.8 A). What is the minimum ampacity of a feeder supplying only these two motors?
Exactly one answer is correct.
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Correct answer to question 13121
- A: 14.3 A
Explanation
125 % of the largest motor plus the other: 7.6 x 1.25 + 4.8 = 14.3 A. Applying 125 % to the smaller motor instead gives 13.6 A, and applying it to both gives 15.5 A.
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