Learning Center

High Voltage Spike (dV/dt) and Motor Protection Methods

By Craig Hartman on 20th Mar 2014

There are two different phenomena that can create high dV/dt and high peak voltages. Reflective Wave Phenomenon Voltage wave reflection is a function of the voltage rise time (dV/dt) and the length of the motor c …

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Variable Frequency Drive Harmonic Mitigation

By Craig Hartman on 20th Mar 2014

Table of Contents Background of Harmonics IEEE 519 - Recommended Practices for Harmonic Control Effects of Harmonics Types of Harmonic Mitigation Equipment Harmonic Mitigation Cost Measurement Considerations Recommendations Appe …

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IP VFD Enclosure Ratings

By Tyler Simmons on 20th Mar 2014

The Ingress Protection (IP) ratings are a standard created by the IEC (International Electrotechnical Commission). It is a European-based standard that has become more common in North America. In this system, the first number in t …

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How to Specify a Variable Frequency Drive

By Luke Lancaster on 20th Mar 2014

How to Specify a Variable Frequency Drive Table of Content Load Type for Variable Frequency Drives Motor Information Supply Power Control Methods for Variable Frequency Drives Speed Reference Alternatives Efficiency and Power Fac …

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What is a Variable Frequency Drive?

By Craig Hartman on 20th Mar 2014

Updated on October 1st 2025 A variable frequency drive (VFD) is a type of motor controller that can adjust the speed of an AC electric motor. It does this by varying the frequency and voltage supplied to the motor. A variable …

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VFD Buying Guide

By Paul Rossiter on 17th Jan 2014

Finding the Best Variable Frequency Drive Finding the perfect VFD or motor controller isn’t easy. A lot depends on the unique needs of your application and system. There isn’t a catch-all model or brand to fall ba …

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