The RMS value is used to quantify the overall "size" of a waveform with a single number. By extension, harmonic amplitudes can be used to describe a complex waveform with…
Analyzing Waveforms White Papers
Power quality white papers on Analyzing Waveforms.
45 white papers in Analyzing Waveforms
Waveform Capture with Transient Capture Overlays
PMI Revolution recorders can record waveform captures and, with the transient capture option, high-speed microsecond-level transient captures. Transient captures have a much higher sampling rate than waveform captures but have…
Understanding Arc Fault Breakers
Arc Fault Breakers (or AFCI breakers) are sensitive breakers that augment traditional breakers' functionality by using logic and signal processing to determine whether or not an arcing condition is present.…
Understanding Harmonic Power
Harmonic power is a complex and often misunderstood topic. This leads to misinterpretations, including using a harmonic power analysis when the measurements aren't physically meaningful. An overview of harmonic power…
CBEMA Graphs Revealed
The CBEMA (Computer Business Equipment Manufacturers Association) curve and the ITIC (Information Technology Industry Council) curve both refer to a similar method to visibly represent voltage events. A graph of…
Cold Load Pickup
One of the most visible customer-facing challenges an electric utility can face comes in the form of voltage interruptions. From the short, fraction-of-a-second momentary to the prolonged, multi-hour (or even…
Spotting Loose Neutrals with Waveform Capture
A "loose neutral" in a residential location can cause equipment damage and even a house fire. An open neutral may start as a high resistance connection that shows subtle signs…
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…
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…
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…
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…
Voltage Regulation Analysis With Daily Profiles
If there were no variations in distribution load, system voltage regulation would be a simple task. But Ohm’s law dictates that a change in load produces a change in delivered…
