INTRODUCTION Modern electronics demand low EMI and EMC conformance, both of which are related to component selection and physical layout in the power supply section of a device. Many more designs are demanding higher power levels alongside high power efficiency, as well as low-noise power supplied to mixed-signal systems. As a result, EMI and EMC challenges are more apparent … [Read more...]
Distinguishing between Surge- and Temporary Overvoltage-Related Failures of Metal Oxide Varistors in End-Use Equipment Designs
Equipment failure resulting from TOVs can be reduced by proper coordination of the line fuse and MOV. Philip F. Keebler, Kermit O. Phipps and Doni Nastasi EPRI Solutions Knoxville, Texas, USA Real world electrical environments in residential, commercial, and industrial facilities experience the gamut of undervoltage and overvoltage disturbances. Examples of undervoltage … [Read more...]
Practical Considerations in Upgrading RF Immunity Test Systems to 6 GHz
Pat Moore, MILMEGA Ltd., UK Introduction With the recent release of IEC61000-4-3 Edition 3, many EMC test houses are actively researching the availability of equipment capable of meeting the testing demands presented by the new 6 GHz upper frequency limit. The conventional solution offered by EMC equipment suppliers has several major disadvantages, particularly as regards … [Read more...]
Fibrous Dust Testing – Genesis and Successful Reproduction of a Menace
Testing services and equipment are now available to analyze designs for fibrous dust susceptibility. Dan Willemin Professional Testing Incorporated, Round Rock, TX, USA Accumulations of dusts have always hampered cooling, to some extent, but dusts and electronics cooling problems of the past usually involved industrial or military applications. To understand why dust has … [Read more...]
Initial Evaluation of Proposed >1-GHz Site Validation Standards
All methods for validating a test site must provide the same unambiguous result indicating that the site meets or does not meet requirements. Ken Hall Hewlett Packard, Roseville, Calif., USA Site validation above 1 GHz has traditionally been done by extending the ANSI C63.4 Normalized Site Attenuation (NSA) requirements to the upper frequency a customer might request for … [Read more...]