62 – Do I need to specify a 200% neutral on my panelboard and transformer if I have a lot of harmonics? [Video]

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What are harmonics? Harmonics are distortions that that occur at a multiple of the fundamental frequency in a power system, which in the US is a 60 hertz sinusoidal wave. Sources of harmonics include non-linear loads that typically include power electronics such as variable frequency drives (VFDs) and LED lights. Current harmonics cause excess heating of transformers and cables, and damage electrical equipment. Harmonics can also cause voltage distortion, often resulting in the misoperation of equipment during critical applications. Calculating harmonics and measuring harmonics are critical steps in selecting the best harmonic solution to reduce the total harmonic distortion or THD on a power system to comply with the IEEE-519 standard. • Neutral Sizing: We emphasize the importance of oversizing the neutral in panel boards and transformers in scenarios with high third harmonic loads, such as computers or LED lights, to prevent overheating issues. This is due to the triplen …