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  As information for our customers, we have included below the current NEC, NESC and RUS requirements for
 electrical ground rods. You can count on Galvan to meet them.
 NEC 2011, 2014, 2017 AND 2020 EDITION
250.52.A Grounding Electrodes / Electrodes Permitted for Grounding
(5) Rod and Pipe Electrodes. Rod and pipe electrodes shall not be less than 2.44 m (8 ft) in length and shall consist of the following materials.
(b) Rod-type grounding electrodes of stainless steel and copper or zinc coated steel shall be at least 15.87 mm (5/8 in.) in diameter, unless listed.
250.53.A Grounding Electrode System Installation / Rod, Pipe, and Plate Electrodes
(2) Supplemental Electrode Required. A single rod, pipe, or plate electrode shall be supplemented by an additional electrode of a type specified in 250.52(A)(2) through (A)(8). The supplemental electrode shall be permitted to be bonded to one of the following:
(1) Rod, pipe, or plate electrode
(2) Grounding electrode conductor
(3) Grounded service-entrance conductor
(4) Non-flexible grounded service raceway
(5) Any grounded service enclosure
Exception: If a single rod, pipe, or plate grounding electrode has a resistance to earth of 25 ohms or less, the supplemental electrode shall not be required.
(3) Supplemental Electrode. If multiple rod, pipe, or plate electrodes are installed to meet the requirements of this section, they shall not be less than 1.8 m (6 ft) apart.
NEC 250.70 Methods of Grounding and Bonding Conductor Connection To Electrodes. Ground clamps shall be listed for the materials of the grounding electrode.
Informational Note: The paralleling efficiency of rods is increased by spacing them twice the length of the longest rod.
094B2 Grounding electrodes / Made Electrodes / Driven rods
(a) Driven rods may be sectional; the total length shall be not less than 2.44 (8 ft). Iron, zinc-coated steel, or
steel rods shall have a diameter of not less than 15.87 mm (0.625 in). Copper-clad, stainless steel, or stainless steel-clad rods shall have a diameter of not less than 12.7 mm (0.5 in).
Copied by permission from NESC-2012 - IEEE 2012 National Electrical Safety Code® Copyright © 2012 IEEE. All rights reserved.
LIST OF MATERIALS – Acceptable for Use on Systems of USDA Rural Development Electrification Borrowers; Informational Publication 202-1, Updated July 2015.
1. New sections for Ground Rods (item ai) have been added to the List of Materials for copper coatings of 10 mil minimum.
a. Item ai – Rods, ground and Rods, ground, sectional
b. New section added, ai(1) – Rods, ground i. Minimum 10 mil copper coating.
ii. Must be Underwriters Laboratory (UL) listed and marked. c. New section added, ai(3) – Rods, ground, sectional
i. Minimum 10 mil copper coating
ii. Must be Underwriters Laboratory (UL) listed and marked.
Note: As of May 23, 2011, RUS Telecom no longer publishes a List of Materials for Telecommunications.
GALVAN INDUSTRIES, INC. Electrical Products Division, (704) 455-5102, 5

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