Conducted Emissions Feedback from VSD-Operated Products

The ubiquitous increase in the use of mains power switching devices has been paralleled by the increase in nuisance tripping of GFCIs and other protection devices. Nuisance tripping can be identified to contain such high frequency signals and these must be properly taken into account when designing proper GFCI operation in this environment.

Experiments of DC Human Body Resistance I

Direct Current (DC) applications have become more prevalent in recent years, primarily due to the increased usage of renewable energy and energy storage systems. A review of the existing safety standards and other literature shows that there is limited experimental data on DC human body resistance. In particular, no information was found by the authors describing the repeatability of DC body impedance and the effect of contact material and other variables.
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Two Measures, Two Levels

What is a “level of protection”? What are “measures of safety”? Why do they apply only to electric shock and not to other injuries?

Mosquito Zapper Bulbs Recalled

ZapBulb mosquito zapper LED light bulbs, manufactured by HAUS and distributed by Creative Sourcing International, are being recalled. The bulb's connector can become separated from its base, posing an electrica... Read More...

Electric Shock From Radios: A Review

During the 1930s, 1940s, and 1950s, Underwriters Laboratories did basic research in the field of safety and published the results of that research in a series of “Bulletins of Research.” At least 58 Bulletins w... Read More...