The historical development of neutral grounding practices

摘要

The historical review given here is limited to system neutral-grounding. The evolution of neutral-grounding practices are described using four flow diagrams, respectively depicting: the early neutral grounding practices in the electrical industry; the low-voltage neutral grounding practices in industry; the medium-voltage neutral grounding practices in industry; and the integration of these figures, with complementary notations, into a composite flow diagram, showing the evolution of neutral grounding practices in the electrical industry. The diagrams indicate the general progression to currently accepted grounding practices and those practices that have been tried but generally proved unsuccessful or severely limited in their applicability.