The document outlines the objectives and performance tasks related to the grounding systems module for power line workers. Key learning outcomes include understanding ground grid systems, installation methods, safety precautions, and various connection techniques. Visual aids and figures are provided to assist with comprehension and practical application.

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Module 82203-12
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Grounding Systems
Module Nine – 82203-12

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Module 82203-12
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Objectives
Upon completion of this module, you will be able to do the following:
1. Explain the purpose of a ground grid system.
2. Describe the methods and materials for installing an underground
grid.
3. Explain the safety precautions used and the PPE required when
repairing and/or expanding an existing ground grid.
4. Describe how connections are made in a ground grid system using
exothermic welded, compression, and mechanical connectors.

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Module 82203-12
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Performance Tasks
Under the supervision of the instructor, you should be able to do the
following:
1. Make connections in a ground grid system using exothermic
welded, compression, and mechanical connectors.

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Figure 1 — Substation

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Figure 2 — Electrostatic induction

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Figure 3 — Electromagnetic induction

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Figure 4 — Energized soil around an energized grounded object

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Figure 5 — Step potential hazard

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Figure 6 — Touch potential hazard

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Figure 7 — Connections to a grounded grid

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Figure 8 — Substation grounding plan

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Figure 9 — Wenner four-point method

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Figure 10 — Electrolytic electrode

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Figure 11 — Ground grid layout

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Table 1 — Ground Grid Conductor Sizes

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Figure 12 — Fence ground grid dimensions

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Figure 13 — Ground grid connections

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Table 2 — Connection Method Advantages and Disadvantages

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Figure 14 — Mechanical connector

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Figure 15 — Cable-to-cable mechanical connectors

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Figure 16 — Mechanical ground connection assembly

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Figure 17 — Compression connector

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Figure 18 — Types of compression connectors

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Figure 19 — Die number stamped in connector body

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Figure 20 — Crimping tool

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Figure 21 — Exothermic weld mold

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Figure 22 — Exothermic electronic igniter

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Figure 23 — Completed exothermic weld

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Figure 24 — Cable-to-cable mold configurations

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Figure 25 — Exothermic welding steps

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Figure 26 — Ground rod placement

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Figure 27 — Ground rod installation

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Figure 28 — Equipotential zone below switch handle

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Figure 29 — Fall-of-potential test setup

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Figure 30 — Ground grid test report form

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Figure 31 — Temporary ground mat

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Supplemental Art

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Course Map

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