July 2026 VFD Filters and Accessories for the Elevator Application

SPECIAL NOTICE: Please check each course for verification of approval before purchasing.

This test is based on the article, VFD Filters and Accessories for the Elevator Application, published in the July 2026 issue and counts as one contact hour (0.1 CEU) of elevator industry continuing education credit. This course is approved by NAEC for CET/CAT and .01 CE QEI and in the following states: Alabama, Arkansas, Colorado, Florida, Georgia, Illinois, Indiana, Kentucky, Maryland, Mississippi, Missouri, Montana, Nevada, Oklahoma, Pennsylvania, Vermont, Virginia, West Virginia, Wisconsin.

Learning Objectives - After reading this article, you should know:

• The basics/three main parts of a six-pulse VFD
• The cause of harmonic distortion and which hormonic orders cause the most significant harmonics in elevator applications
• The multiple methods used to mitigate harmonic distortion and prolong the lifespan of equipment in the electrical and elevator system
• The cost versus performance of the system to determine the best method for the application at hand
• The difference between TDD and THDi, their uses and which is better for describing harmonic distortion over time in an elevator system

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