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STANDARDS AND GUIDELINES FOR COMMUNICATION SITES GROUNDING (EARTHING) ELECTRODE SYSTEM COMPONENT AND INSTALLATION
REQUIREMENTS
4.4.1.4 GROUND PLATE ELECTRODES
Ground plates (Figure 4-15) may be used in special cases, or if specifically engineered into the design
of the grounding (earthing) electrode system. Requirements for the use of ground plate electrodes are
listed below:
• Ground plates should only be used if soil conditions prohibit the use of standard ground rods, or if
specifically engineered into the grounding electrode system.
• Ground plates should be UL listed (or equivalent).
• Ground plates shall be constructed of copper or copper-clad steel.
• Ground plates shall expose not less than 0.37 m 2 (2 ft. 2 ) of surface to exterior soil (MIL-HDBK-
419A, section 2.5.5; NFPA 70-2005, Article 250.52; and NFPA 780-2004, section 4.13.6.1).
• Ground plates shall have a minimum thickness of 1.5 mm (0.06 in.) (MIL-HDBK-419A, section
2.5.5 and NFPA 70-2005, Article 250.52).
• Ground plates shall be free of paint or other nonconductive coatings (NFPA 70-2005, Article
250.53 and NFPA 780-2004, section 4.13.2.2).
• Ground plates shall be buried not less than 762 mm (30 in.) below the surface of the earth (NFPA
70-2005, Article 250.53). If soil conditions do not allow the ground plate to be buried at this depth,
see “Shallow Topsoil Environments” on page 4-97 for additional information.
• Where practical, a ground plate shall be embedded below permanent moisture level
(BS 7430:1998, clause 10 and NFPA 70-2005, Article 250.53).
• Ground plates should be installed vertically to allow for minimum excavation and better contact
with the soil when backfilling (BS 7430:1998, clause 10 and IEEE STD 142-1991, section 4.2.4).
See Figure 4-16.
SERRATED EDGES PROVIDE MORE
EDGE SURFACE
FIGURE 4-15 TYPICAL GROUND PLATES
STRAIGHT EDGES
68P81089E50-B 9/1/05 4-19