IEEE 519-2014 specifies measurements, analysis methods, and limits for harmonic voltage and current. A full IEEE 519 study is a straightforward, but rigorous analysis that can require multiple recordings and…
White Papers
Browse our library of power quality technical resources.
185 results in Power Quality — Clear
Power Quality
Understanding IEEE 1159 Definitions
It is very important to have recommended guidelines and practices in place regarding power quality monitoring with the use of consistent terminology and definitions of power quality phenomena. This is…
Using Cycle Stripcharts
Stripchart recording is an important tool for analyzing complex data. It provides a visual means to easily digest extensive quantities of recorded information over long time periods. In most cases,…
Catching VFD Failures
Variable Frequency Drives (VFDs) present unique challenges as both a source of PQ problems as well as being sensitive to incoming voltage quality. A frequent complaint with a troublesome VFD…
Understanding How Harmonics Affect Power Factor
Power Factor (PF) is a measure of the efficiency of electric power delivery to a load. Traditionally the phase shift from inductive loads was the major cause of poor PF…
IEEE 519 Harmonics in Residential Locations
IEEE 519 specifies the measurement technique and limits for harmonics in a wide variety of locations, from transmission through distribution. For the first time, the 2014 edition also provides separate…
Voltage Sag Source: Upstream or Downstream?
The first step in voltage sag mitigation is finding the source of the sag. In a power quality recording, spotting the voltage sag itself is often easy, but determining whether…
Power Factor Correction Capacitors and Harmonics: How PFC Capacitors Affect Harmonic Levels
Power networks have become increasingly more complex with the rapid growth of non-linear loads. These additions place significant burden on a network, resulting in a reexamination of today's installations. This…
Understanding RMS Measurements
Power Monitors, Inc. provides a wide array of power quality test instrumentation. These devices are used to measure line voltage, current and power from or to a number of different…
Computing IEEE 519-2014 Short Time Harmonic Values
IEEE 519-2014 specifies two time periods for analyzing harmonic data: "very short time", or 3 seconds, and "short time" or 10 minutes. For achieving the best resolution, the 3 second…
Electrical Undervoltage and Power Quality
In this whitepaper, the term undervoltage is explained, some typical causes of undervoltages are given, and the effects of undervoltage on customer loads is described. IEEE 1159-2009, IEEE Recommended Practice…
Data Collection During Quick Fluctuations in Line Voltage
One of the most useful methods for examining specific power quality activity is through filtered predesignated reports. At PMI we've achieved this with our "Significant Change Report." The primary use…
