Question 13092 of 749 · Maryland Journeyperson Electrician Exam
A motor has a nameplate current of 40 A, a service factor of 1.0 and a temperature rise of 50 °C. What overload rating is required under the basic rule?
Exactly one answer is correct.
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Correct answer to question 13092
- D: 46 A
Explanation
Motors that have neither a service factor of 1.15 or more nor a temperature rise of 40 °C or less get overloads at 115 % of nameplate current: 40 x 1.15 = 46 A. 50 A is the 125 % value.
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