How do you know if you have power quality problems?
The answer is you either conduct a battery of specific tests in the course of a power quality analysis, or you produce reports from your power quality monitor. Fully executing either approach requires expertise not typically present in plant engineering.
It might be better to ask how you know to suspect power quality problems. Here are some common signs, but note that their absence does not mean your power quality is necessarily what it should be:
•A high rate of motor bearing failures and/or motor winding failures.
•The mechanics find pitted bearings in mechanical drives and other equipment under their purvey.
•Circuit board replacement is a normal occurrence. Same for PLC module replacement.
•Lights flicker. Lights don’t seem bright enough. Lighting system component replacement is a normal occurrence.
•Neutral conductors appear discolored.
•Nuisance breaker trips occur, but their source is rarely, if ever, identified.
•Insulation resistance (IR) testing shows cable failure at an abnormal rate. Note that a qualified electrical testing firm can tell you from experience whether the rate is abnormal.
If you have any of these symptoms, suspect one or more power quality problems. You may be able to identify some issues with a little sleuthing and some basic measurements, but you’ll probably need a qualified firm to do a complete workup.
About the Author
Mark Lamendola
Mark is an expert in maintenance management, having racked up an impressive track record during his time working in the field. He also has extensive knowledge of, and practical expertise with, the National Electrical Code (NEC). Through his consulting business, he provides articles and training materials on electrical topics, specializing in making difficult subjects easy to understand and focusing on the practical aspects of electrical work.
Prior to starting his own business, Mark served as the Technical Editor on EC&M for six years, worked three years in nuclear maintenance, six years as a contract project engineer/project manager, three years as a systems engineer, and three years in plant maintenance management.
Mark earned an AAS degree from Rock Valley College, a BSEET from Columbia Pacific University, and an MBA from Lake Erie College. He’s also completed several related certifications over the years and even was formerly licensed as a Master Electrician. He is a Senior Member of the IEEE and past Chairman of the Kansas City Chapters of both the IEEE and the IEEE Computer Society. Mark also served as the program director for, a board member of, and webmaster of, the Midwest Chapter of the 7x24 Exchange. He has also held memberships with the following organizations: NETA, NFPA, International Association of Webmasters, and Institute of Certified Professional Managers.