--- title: Understanding Harmonics description: Read how to measure and record harmonics using PMI equipment and why this is useful. image: https://library.powermonitors.com/hubfs/Blog_Posts/WP146/Understanding%20Harmonics_04.png --- [![PMI\_Logo\_White\_Slogan](https://library.powermonitors.com/hs-fs/hubfs/Branding%20-%20Logos%20and%20Designs/PMI_Logo_White_Slogan.png?width=655&height=175&name=PMI_Logo_White_Slogan.png "PMI_Logo_White_Slogan")](https://powermonitors.com) [![PMI Logo: Tools you Need. People you Trust.](https://library.powermonitors.com/hubfs/PMI_Website/logo.svg "PMI Logo: Tools you Need. People you Trust.")](http://powermonitors.com) [![PMI Logo: Tools you Need. People you Trust.](https://library.powermonitors.com/hubfs/PMI_Website/logo.svg "PMI Logo: Tools you Need. 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[Join Our Team!](https://info.powermonitors.com/join-pmi) - [Receive our Newsletter](https://info.powermonitors.com/email-subscribe-page) - [PQ Resources](https://info.powermonitors.com/power-quality-resources) - [Power Quality Solutions](https://powermonitors.com/power-quality-solutions/) - [Who We Serve](https://powermonitors.com/sales-representatives/) - [Account](https://powermonitors.com/account/) This is a search field with an auto-suggest feature attached. - There are no suggestions because the search field is empty. ![PMI-Logo-Phone-Site-2023-900px](https://library.powermonitors.com/hs-fs/hubfs/PMI-Logo-Phone-Site-2023-900px.png?width=113&name=PMI-Logo-Phone-Site-2023-900px.png "PMI-Logo-Phone-Site-2023-900px") # Understanding Harmonics   |   , ## **Demystifying Harmonics: Understanding Nonlinear Loads and Power Quality Challenges** This white paper explores the fundamental concepts behind harmonics in AC power systems, focusing on the impact of nonlinear loads such as Variable Frequency Drives (VFDs) and electronic power supplies. It explains how distorted current waveforms arise, how Fourier analysis decomposes these into harmonics, and why understanding harmonic content is essential for diagnosing and mitigating power quality issues. The paper also discusses practical measurement techniques and the limitations of harmonic analysis in more complex scenarios. Beyond fundamentals, it clarifies why rectifier-capacitor supplies draw narrow peak currents (small conduction angles), why odd harmonics dominate (3rd, 5th, 7th), and how resonances from capacitors and inductors can amplify distortion at frequencies. **Key topics include:** \- Introduction: The Rise of Nonlinear Loads \- Sine Waves and Linear Load Behavior \- Nonlinear Loads and Harmonic Distortion \- Fourier Analysis and Harmonic Decomposition \- Practical Examples of Harmonics in Power Systems \- Measurement and Analysis Techniques \- System Resonance and Harmonic Mitigation \- Limitations and Interharmonics **Why utilities should care:** Accurate harmonic analysis enables better diagnosis of power quality issues, supports targeted mitigation strategies, and helps prevent equipment malfunctions or system inefficiencies caused by nonlinear loads and resonance effects in modern distribution networks. Practical takeaways include trending total harmonic distortion (THD) with harmonic spectra, comparing neutral and phase currents to spot triplen issues, and watching for resonance near capacitor-bank tuning. Most PMI recorders measure harmonics directly, and [ProVision](https://powermonitors.com/product/provision/) computes spectra from any captured waveform, enabling before/after checks when adjusting drive settings or adding filters. With a clearer grasp of what the numbers mean, engineers prioritize mitigation with evidence, prevent overheating and nuisance trips, and translate complex findings into recommendations for customers and regulators. Define thresholds, schedule periodic scans, and standardize reports so teams compare feeders consistently, triage hotspots, and justify filters or equipment upgrades with defensible, trend-backed evidence. You may also enjoy...   - - - - ## Speakers ### [Alvin Rogers](https://library.powermonitors.com/understanding-harmonics#inline-content-1speakers)[Follow me on LinkedIn](https://www.linkedin.com/apex-alvinrogers) Director of Sales Omnicorp Alvin Rogers Director of Sales Omnicorp About Alvin Rogers Alvin Rogers is a highly accomplished and sought-after speaker, renowned for their expertise and captivating stage presence. With a diverse background in \[relevant field or industry\], they bring a wealth of knowledge and experience to every speaking engagement. Their dynamic and engaging style seamlessly combines powerful storytelling with actionable insights, leaving audiences inspired and equipped with practical strategies for success. Alvin has delivered impactful keynote addresses at prestigious conferences and corporate events worldwide, consistently receiving rave reviews for their ability to connect with and energize audiences. Whether addressing topics such as \[specific areas of expertise\], leadership, or innovation, Alvin is dedicated to empowering individuals and organizations to reach their full potential. [LinkedIn](https://www.linkedin.com/apex-alvinrogers) [Facebook](https://www.facebook.com/apex-alvinrogers) [Instagram](https://www.instagram.com/apex-alvinrogers) [Twitter](https://www.twitter.com/apex-alvinrogers) ### [Lisa Smith](https://library.powermonitors.com/understanding-harmonics#inline-content-2speakers)[Follow me on LinkedIn](https://www.linkedin.com/apex-lisasmith) Creative Director Megacorp Lisa Smith Creative Director Megacorp About Lisa Smith Lisa Smith is a highly accomplished and sought-after speaker, renowned for their expertise and captivating stage presence. With a diverse background in \[relevant field or industry\], they bring a wealth of knowledge and experience to every speaking engagement. Their dynamic and engaging style seamlessly combines powerful storytelling with actionable insights, leaving audiences inspired and equipped with practical strategies for success. Lisa has delivered impactful keynote addresses at prestigious conferences and corporate events worldwide, consistently receiving rave reviews for their ability to connect with and energize audiences. Whether addressing topics such as \[specific areas of expertise\], leadership, or innovation, Lisa is dedicated to empowering individuals and organizations to reach their full potential. [LinkedIn](https://www.linkedin.com/apex-lisasmith) [Facebook](https://www.facebook.com/apex-lisasmith) [Instagram](https://www.instagram.com/apex-lisasmith) [Twitter](https://www.twitter.com/apex-lisasmith) ### [James McGiven](https://library.powermonitors.com/understanding-harmonics#inline-content-3speakers)[Follow me on LinkedIn](https://www.linkedin.com/apex-jamesmcgiven) President Minicorp James McGiven President Minicorp About James McGiven James McGiven is a highly accomplished and sought-after speaker, renowned for their expertise and captivating stage presence. With a diverse background in \[relevant field or industry\], they bring a wealth of knowledge and experience to every speaking engagement. Their dynamic and engaging style seamlessly combines powerful storytelling with actionable insights, leaving audiences inspired and equipped with practical strategies for success. James has delivered impactful keynote addresses at prestigious conferences and corporate events worldwide, consistently receiving rave reviews for their ability to connect with and energize audiences. Whether addressing topics such as \[specific areas of expertise\], leadership, or innovation, James is dedicated to empowering individuals and organizations to reach their full potential. [LinkedIn](https://www.linkedin.com/apex-jamesmcgiven) [Facebook](https://www.facebook.com/apex-jamesmcgiven) [Instagram](https://www.instagram.com/apex-jamesmcgiven) [Twitter](https://www.twitter.com/apex-jamesmcgiven) Power Monitors, Inc. is an industry-leading product design and manufacturing firm based in Mt. Crawford, Virginia. PMI strives to solve power quality problems by listening to our customers and working with them to design and manufacture products. Total customer satisfaction is the primary goal of all PMI staff. Please browse our site or call us to learn more about PMI and how we can help meet your power monitoring needs.   800 N Main St Mt Crawford, VA 22841 | Toll Free 800.296.4120 | Fax 540.432.9430 | © 2025 Power Monitors, Inc. ###### Follow Us [Follow us on Facebook](https://www.facebook.com/powermonitors/) [Follow us on LinkedIn](https://www.linkedin.com/company/power-monitors) [Follow us on Twitter](https://twitter.com/powermonitors) [Follow us on Instagram](https://info.powermonitors.com/email-subscribe-page) - [Support](https://powermonitors.com/support) - [Library](https://library.powermonitors.com) - [Training](https://info.powermonitors.com/training) - [Contact](https://powermonitors.com/contact/) - [Products](https://powermonitors.com/products/) - [- Bolt](https://powermonitors.com/product/bolt/) - [- Revolution](https://powermonitors.com/product/revolution/) - [- Seeker](https://powermonitors.com/product/seeker/) - [- Guardian](https://powermonitors.com/product/guardian/) - [Careers](https://info.powermonitors.com/join-pmi) - [Terms and Conditions](https://powermonitors.com/terms-and-conditions/)