--- title: Voltage Tug-of-War The Silent VFD Killer description: How even small amounts of voltage unbalance can degrade variable-frequency drives (VFDs). image: https://library.powermonitors.com/hubfs/White_Papers/White%20Paper%20Header%20Images/Voltage%20Tug-of-War%20The%20Silent%20VFD%20Killer.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") # Voltage Tug-of-War The Silent VFD Killer   |   , ## **Diagnose and Prevent VFD Failures** This white paper explains how even small amounts of voltage unbalance can degrade variable-frequency drives (VFDs). While VFDs are built on advanced power electronics, their six-pulse diode bridge rectifiers remain vulnerable to unequal phase voltages. Just a few percent of unbalance is enough to distort current sharing, increase ripple, shorten lifetime of diodes, capacitors, inverters, and ultimately the motor itself. Left unaddressed, these stresses shorten drive life, cause nuisance trips, and compromise reliability in critical applications. **Key topics include:** \- How phase voltage disparity leads to diode thermal runaway and capacitor heating \- Ripple current escalation and its impact on DC-link life expectancy \- Motor damage pathways including over-voltage spikes, insulation stress \- Harmonic side effects: triplen harmonics \- Monitoring strategies using PMI Revolution, Seeker, and Bolt recorders to pinpoint unbalance issues **Why utilities should care:** Voltage unbalance may seem minor, but its consequences are major—reduced motor life, unexpected downtime, and costly equipment replacements. With high-resolution waveform capture and advanced analytics in PMI PQCanvass and ProVision software, engineers can distinguish whether a drive is the victim or the culprit, identify imbalance sources, and apply corrective measures such as load redistribution, line reactors, or filtering. Early detection and proactive maintenance can stop this “silent killer” before it escalates into costly failures. You may also enjoy...   - - - - ## Speakers ### [Alvin Rogers](https://library.powermonitors.com/voltage-tug-of-war-the-silent-vfd-killer#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/voltage-tug-of-war-the-silent-vfd-killer#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/voltage-tug-of-war-the-silent-vfd-killer#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. 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