Question 13020 of 749 · Maryland Journeyperson Electrician Exam
What is the line-to-neutral voltage of a 480Y/277 volt system, calculated from the 480 volt line-to-line value?
Exactly one answer is correct.
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Correct answer to question 13020
- D: 277 V
Explanation
In a wye system the line-to-neutral voltage equals the line-to-line voltage divided by 1.732: 480 / 1.732 = 277 V. Halving the voltage (240 V) only works for a single-phase center-tapped system.
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