How to Quantify Harmonics13Individual Harmonic Distortion (IHD) LevelPercentage of individual harmonic relative to fundamentalTotal Harmonic Distortion (THD) LevelPercentage of RMS of all harmonics relative to fundamentalIEEE 519 specifies limitsISC/ILIHD for Odd Harmonic CurrentsTHD for Odd Harmonic Currentsh < 1111 h < 1717 h < 2323 h < 3535 h100015.0%7.0%6.0%2.5%1.4%20.0% 2011 EnerNex. All Rights Reserved. www.enernex.com