Understanding the capabilities of your monitor will help you
interpret readings more accurately when investigating power
quality problems.  Years ago, power quality concerns were
primarily limited to the effects of voltage on computers and
other microprocessor-controlled equipment. However, as
electronics took over the business world, the equipment itself
became its own worst enemy. In today's high-tech society, the
majority of electronic equipment is not just susceptible to
power quality problems; it frequently creates them. This reality
continues to increase the need for better power monitoring.
What's your first step to troubleshooting power quality
problems? First, you need a monitor that accurately measures
voltage and current waveforms. Although most electrical
professionals usually consider sample rate, most overlook the
other design factors that affect a monitor's overall
performance.  The figure (available in print version, page 16)
demonstrates the fallacy of a common meter myth. It shows about
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