PQubes Catch the Mexicali Earthquake Rippling Through the Western Power Grid
A powerful earthquake struck on the Mexico–California border on April 4th, 2010. Although the earthquake was rated at 7.2 on the Richter Scale, very few people were injured, and property damage was limited. For those in the electric power business, it was fascinating to see how the earthquake affected the frequency of the entire Western U.S. Interconnect Grid – perhaps it caused a major generator to drop off line.
Sophisticated little PQube instruments, from Power Standards Lab, captured the frequency glitch at several widely separated locations (Lawrence Berkeley Lab, PowerCET in Santa Clara, and a waste treatment plant near San Diego) demonstrating once again that even huge grids really are one giant machine.
Power Standards Lab describes the PQubes as "an entirely new idea: combine a hyper-accurate energy monitor with a world-class power quality monitor. Then squeeze it into a compact, low-cost package that require any software at all." The devices capture disruptive voltage disturbances every time they occur, using time-stamped pictures of the waveforms, and Excel®-compatible CSV spreadsheet files. They have energy and peak metering, including kilowatt-hours, kVA, kVA-hours, true Power Factor, peak amps, peak kVA, peak watts, unbalance, and a Carbon footprint meter that uses a patent-pending algorithm. Their tiny size make them well suited for embedding in sensitive equipment which quickly reduces service costs and provides critical data for improving energy efficiency.
Among the prominent features of the PQube:
– Three-phase and single-phase monitoring up to 690V, 50/60/400Hz.
– Power Quality monitoring: voltage dips, swells, and interruptions – waveforms and RMS graphs, over-frequency and under-frequency events, 1-microsecond high-frequency impulse detection, THD, TDD, and time-triggered snapshots, voltage and current unbalance, and detailed event recording, plus daily, weekly, and monthly trends, cumulative probability, histograms, and more.
– Advanced energy monitoring: Watts, VA, VAR’s, true Power Factor, Watt-hours, VA-hours, daily and accumulated CO&sub2;, and CO&sub2; rate (patent pending), peaks: single-cycle peak, 1-minute, and 15-minute averages, CT ratios support up to 50,000A, PT ratios support up to 6,900,000V, and daily, weekly, and monthly trends, as well as load duration curves and more.
The PQube also automatically writes these files on a standard digital camera SD card. It has a built-in Li-Ion UPS, with power from 24Vac, 24-48Vdc, or optional 100~240Vac power supply.
