Question 13088 of 731 · Texas Journeyman Electrician Exam
A 10 hp, 230 volt, three-phase motor has a table full-load current of 28 A. What is the maximum dual-element time-delay fuse size under the basic percentage of 430.52?
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Correct answer to question 13088
- D: 50 A
Explanation
Dual-element time-delay fuses may be sized at 175 %: 28 x 1.75 = 49 A, and the next higher standard size is 50 A. 70 A uses the 250 % breaker value, and 90 A uses the 300 % nontime-delay fuse value.
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