Voltage unbalance can cause severe heating in motors and large DC power converters. Although most voltage unbalance is caused by unequal loading among phases, shifts in voltage phase angle can…
White Papers
Browse our library of power quality technical resources.
414 white papers
Transient Capture vs. Waveform Capture
Most PMI recorders include waveform capture, and the Revolution optionally includes a high-speed microsecond-level transient capture system. Although PMI waveform capture and transient capture seem very similar on the surface,…
Voltage Swell from Recloser Operation
A recloser is most associated with brief voltage interruptions, possibly followed by an extended outage if a fault cannot be cleared. Upstream customers experience voltage sag during the reclose attempts,…
Overcurrent Protection with Fused Leads
PMI offers a fused voltage lead kit for increased safety with the Revolution and Eagle power recorders. Although not required to meet UL safety standards with these recorders, the fused…
IEEE Std. 141 Flicker Curve vs. IEEE 1453 Flicker Meter
In this whitepaper I describe and compare two of the IEEE Flicker standards, the older standard 141 (the GE Flicker Curve), and the newer IEEE 1453 (Flicker Meter standard). The…
Customizing the GE Flicker Curve
Flicker is still one of the top PQ complaints reported to utilities, therefore it is important to be able to effectively quantify and evaluate these types of problems. In many…
Browser Security and Performance with Canvass
Canvass is a powerful graphical web application for the viewing and analysis of voltage, current, and power data collected by PMI Boomerangs and Revolutions. Hosted at https://canvass.powermonitors.com, the application provides…
Getting Started with the Pole Mount Boomerang
This white paper will explain the process of installing and communicating with a Pole mount Boomerang voltage/current/power sensor (Figure 1). The pole mount option includes a rugged, weatherproof NEMA 4X…
Voltage and Current Scaling in Canvass
The ability to store and apply multiplicative scaling factors to voltage, current, and power data is a new feature recently added to the cloud-based Canvass system. Scale factors have a…
Understanding PMI Data Record Types – Part 3
The job of any power monitor is to record all interesting data, and leave unrecorded the vast majority of boring, unremarkable data. The tricky part for a monitor is deciding…
Using TLAR CTs
TLARs are PMI's iron core CT (Current Transformer) clamps, available in various probe and channel configurations. These clamps are used for lower range current measurements, with ranges of 20A or…
The New / Improved IP Address Resolution Server
PMI's Revolution can be configured to use a cellular modem as one of its many different means of connectivity. When this option is present the modem can be configured in…