Ensure resistance to ground is no larger than 25 ohms. If the equipment in the nearby shelter is critical, then <5 ohms resistance to ground is recommended – this may require supplemental grounding techniques and an extensive below-grade electrode system. Transient voltage introduced. Protective grounding standard introduced in Revision G With the introduction of Revision G of the ANSI/TIA 222 standard for antenna supporting structures and antennas, effective January 1, 2006, the standard for protective grounding has increased the minimum number of ground rods required and has. TVA carried out 10,600 measurements of tower footing resistance in early 1990s. 500-kV towers had insulated overhead groundwires. Analyzed with Pearson Classification. TVA and REN data have similar (log-normal) distributions of. In this paper, nVent explores transmission line design, potential risks associated with transmission systems, and common grounding methodologies in installations where achieving a ground resistance value is challenging. This paper reviews the fundamental concepts of tower. GROUNDING DESIGN THEORY.
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