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…
White Papers
Browse our library of power quality technical resources.
179 results in Power Quality — Clear
Power Quality
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…
Linear vs Non-Linear Loads
In this white paper I define linear and non-linear loads, describe what characteristics cause a load to be linear or nonlinear, and show how these load types can affect the…
Adjusting Waveform Capture Sampling Rates
Waveform capture is one of the most important data types available for PQ analysis. The sample-level data provides detailed information for voltage disturbances such as oscillatory transients, notches, sub-cycle overvoltages…
Voltage Notching Effects on Harmonic Distortion
Notching is a voltage waveform distortion resulting from short-duration high current pulses. These distortions typically present themselves graphically as a “notch” in the time domain representation of the waveform. The…
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…
Understanding Variable Frequency Drives
This paper covers what a variable frequency drive (VFD) is, the different types of VFDs, their functions, and their benefits. Also covered are issues related to VFDs, some solutions to…
Hardware for Power Quality and Distribution Monitoring
PMI offers an array of monitoring devices for just about any utility distribution monitoring need. Data needs, location, and communications requirements are all factors involved in selecting the right monitor…
Sampling Rate in PQ Recorders
A common specification in power quality recorders such as PMI's Revolution, Guardian, or Eagle products is the sampling rate of the device. Users know this is an important number and…
Flicker Investigation Strategy
Flicker is defined as fluctuation or wavering in visible light intensity due to voltage variations. These variations in voltage are caused by fluctuations in the load through the system source…
