Voltage Tolerance Boundary

Published by Pacific Gas and Electric Company (PG&E), January 1999. The only national standard for utilization voltage regulation is ANSI C84.1. Its title is American National Standard for Electric Power Systems and Equipment – Voltage Ratings (60 Hertz). The first version in 1954 was a combination of two standards, one from the Edison Electric InstituteContinue reading “Voltage Tolerance Boundary”

Interpretation & Analysis of Power Quality Measurements

Published by Christopher J. Melhorn, Electrotek Concepts, Inc. Knoxville, Tennessee Mark F. McGranaghan, Electrotek Concepts, Inc. Knoxville, Tennessee ABSTRACT This paper describes advances in power quality monitoring equipment and software tools for analyzing power quality measurement results. Power quality monitoring has advanced from strictly problem solving to ongoing monitoring of system performance. The increased amountContinue reading “Interpretation & Analysis of Power Quality Measurements”

Simple Rules for Solving Power Quality Mysteries

Published by Richard P. Bingham, Dranetz Technologies, Inc., USA Prepared for the Conference on Protecting Electrical Networks and Quality of Supply, Heathrow, UK, 22-23 January 1997 ABSTRACT The typical power quality problem starts with a frantic call to the facility’s engineer or electric shop supervisor concerning some malfunction that has either shut down production orContinue reading “Simple Rules for Solving Power Quality Mysteries”

Determining Sag Directivity

Application Note INTRODUCTION Voltage sags, or dips are the most common type of power quality (PQ) event. Knowing the directivity of the sag, or where it originated, is very import when trying to locate its source and to ultimately mitigate the problem. This application note outlines some rules of thumb to help determine the directivityContinue reading “Determining Sag Directivity”

Beware Rotation Issues on Transformers

Published by Tom Shaughnessy, Shaughnessy Consulting Services 208 Jasper Way, San Marcos, CA 92078 408-666-4009 Background Phase rotation is something that contractors and electricians routinely check during construction and installation of motors and UPS systems. In facilities with only one service, seldom does a rotation change require utility involvement. However, complications can and do ariseContinue reading “Beware Rotation Issues on Transformers”