You hook up a power quality analyzer to a Variable Frequency Drive (VFD) input and notice a Total Harmonic Distortion (THD-V) of 8%. The facility manager says it is fine. What is the standard IEEE 519 recommendation for voltage THD at the point of common coupling?
Answers
AVoltage THD should generally be kept below 5% to prevent equipment damage and overheating
BIEEE 519 does not regulate voltage harmonics, only current
CVoltage THD only matters if it drops below 2%
DVoltage THD is acceptable up to 15%
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