Vincente Rodriguez, ETS-Lindgren LP., Cedar Park, Texas, USA Antennas have been used in EMC measurements since the early days. Knowledge of the antenna pattern was not a requirement of the standards. While MIL STD 461 and some SAE standards called for information on the half power beamwidth, most standards did not require any knowledge of the antenna radiation characteristics. … [Read more...]
Electromagnetic Interference Sources and Their Most Significant Effects
As the density of the electromagnetic environment continues to increase, the concern about its effects from sources producing EMI also increases. Advances in technology and the number of products produced are having a significant effect on the efforts aimed at maintaining the required operation and interoperability of products and systems used in our society. These events had … [Read more...]
Accurate Feedthrough Capacitor Measurements at High Frequencies Critical for Component Evaluation and High Current Design
The shunt capacitor is the critical element in almost all low pass filters. Feed-through capacitors are configured as a center electrode passing through a grounded housing, which contains the desired capacitance from the electrode to the grounded housing, and practically eliminates lead inductance. This article will explain the importance of feedthrough capacitors, and provide … [Read more...]
A Risk Assessment for Lightning Protection System (LPS)
Bryan Cole, Technology Research Council, Nichols, New York, USA Many articles, papers, and standards have been written and/or developed documenting proper application of surge protection devices (SPDs), identification of SPD performance characteristics, proper SPD safety requirements, etc. However, there are minimal articles on describing when an engineer should specify SPDs … [Read more...]
Going from Analog to Digital
Philip F. Keebler, EMC Group, Electric Power Research Institute, Knoxville, Tennessee USA; Stephen Berger, TEM Consulting, LLC, Georgetown, Texas USA Nuclear power plants (NPPs) in the United States have been undergoing upgrades from analog instrumentation and control (I&C) equipment to digital equipment over the past several years. Upgrades have been occurring on the … [Read more...]
Numerical Solution of Complex EMC Problems Involving Cables with Combined Field / Transmission Line Approach
Many problems of electromagnetic compatibility and interference involve cables, which either radiate through imperfect shields and cause coupling into other cables, devices or antennas, or which receive (irradiation) external electromagnetic fields (radiated from antennas or leaked through other devices) and then cause disturbance voltages and currents potentially resulting in … [Read more...]
High Power Electromagnetic (HPEM) Threats to the Smart Grid
This paper is focused on the threats and impacts of High Power Electromagnetic (HPEM) environments on the U.S. Power Grid and further introduces the implications of making the power grid “smarter” through the introduction of additional electronics. These Smart Grid electronics may introduce additional vulnerabilities if the grid is exposed to the high power EM threats of … [Read more...]
Measurement Uncertainty for Conducted and Radiated Emissions
One of the key elements to making scientific measurements in an EMC lab in today's modern world is having the engineers understand and control the Measurement Uncertainty (MU) of the instrumentation used for making conducted and radiated emission measurements. The emission levels measured by an accredited lab must have measurement uncertainties below certain levels to be … [Read more...]
Wireless Approvals for Japan: A Hiro's Tale
Hiro dug into his soup. “Did your dad fight in the war?” Nodding, slurping up fat udon noodles, “Korea,” pausing and picking up a napkin to dab his chin. “My father was an engineer, highways and bridges, mostly in the North.” Hiro put down his napkin, laid his fast-food chopsticks across his bowl and picked up the chopstick wrapper. He meticulously folded the long paper in … [Read more...]
Troubleshooting Radiated Emissions Using Low-Cost Bench-Top Methods
Kenneth Wyatt Wyatt Technical Services LLC Editor's Note: Click on the pdf icon at left for a printable copy of this article. Because time-to-market and budget factors often drive many of today’s high-tech designs, electromagnetic compatibility (EMC) issues often surface at the last moment in the design cycle, potentially delaying product introductions. Very often, simple … [Read more...]
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