A commercial office building with hundreds of LED drivers and computers has a neutral conductor running very hot in the 3-phase wye feeder. The phase currents are perfectly balanced. What is causing the overheating?
Answers
AThere is a severe ground fault in the building
BHigh triplen harmonics (3rd, 9th, 15th) from the non-linear loads are summing on the neutral
CThe neutral wire is improperly sized for standard linear loads
DThe power company is delivering a higher voltage than normal
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