A grounding system’s purpose is to use the earth as a current-carrying conductor to dissipate noise currents and conduct dangerous lightning and power fault currents. Earth is a very good electrical conductor due to its mass and its availability to everyone at all locations throughout the world. This global access to the earth allows grounding systems installed on opposite sides of the world to connect. Read more…
Prior to the 2018 version, NFPA 70E simply cautioned that “greater emphasis may be necessary with respect to de-energizing” equipment with incident energy (IE) exceeding 40 cal/cm2, “when exposed to electrical hazards.” This nebulous direction was applied within the industry by simply labeling everything over 40 cals as “Dangerous – No PPE Exists.” In its new 2018 version, NFPA 70E eliminated this cautionary language. This may lead some to infer that working on energized equipment…
