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…
Power Quality White Papers
Power quality white papers on Power Quality.
203 white papers in Power Quality
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…
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…
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…
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…
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…
Capturing Oscillatory Transients
Oscillatory transients are caused by switching operations, nearby lightning strikes, or other impulsive noise exciting electrical resonances present on the network. The most common in the distribution system is defined…
Plotting PQ Events on the CBEMA – ITIC Curve
The CBEMA and ITIC curves are used to show voltage events. Some PMI recorders can record these events and then ProVision can be used to plot these events on the…
Analyzing Voltage Sags with RMS Capture
This white paper covers the topic of voltage sags and a sometimes under-used graphing feature in Provision called the RMS Capture graph. The RMS Capture graph can be very revealing…
Interharmonic Recording and Data Analysis
Interharmonics are one of the most complex power quality quantities to measure and analyze. The concepts are advanced, the terminology is confusing, the raw data is voluminous, and the interpretation…