In electrical engineering, ground or earth may be the reference point in an electrical circuit from which other voltages are measured, or a common return path for electric current, or a direct physical connection to the Earth. (Wikipedia.org)
This free article is all about Circuit Grounds and Its practices and applications written by George Hunka, Undergraduate Laboratory, Dept. of EE, University of Pennsylvania. This article is divided into sections such as follows: Introduction, Concept of Earth Ground, Common Power Supply Error IV Examples of Return Symbols, Shock Hazard Protection, Grounding Considerations, Basic Grounding Practices (single point, ground bus, protoboard grounding, and analog/digital grounds).
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