Page 733 - 2018_IRC

SERVICES

Where multiple concrete-encased electrodes are present electrode of one grounding system shall be not less than 6 feet
at a building or structure, only one shall be required to be (1829 mm) from any other electrode of another grounding sys-
bonded into the grounding electrode system. [250.52(A)(3)] tem. Two or more grounding electrodes that are effectively
E3608.1.3 Ground rings. A ground ring encircling the bonded together shall be considered as a single grounding
building or structure, in direct contact with the earth at a electrode system. That portion of a bonding jumper that is the
depth below the earth’s surface of not less than 30 inches sole connection to a rod, pipe or plate electrode shall not be
(762 mm), consisting of at least 20 feet (6096 mm) of bare required to be larger than 6 AWG copper or 4 AWG aluminum
copper conductor not smaller than 2 AWG shall be consid- wire. [250.53(A)(1), 250.53(B), 250.53(E)]
ered as a grounding electrode. [250.52(A)(4)] E3608.4 Supplemental electrode required. A single rod,
E3608.1.4 Rod and pipe electrodes. Rod and pipe elec- pipe, or plate electrode shall be supplemented by an addi-
trodes not less than 8 feet (2438 mm) in length and con- tional electrode of a type specified in Sections E3608.1.2
sisting of the following materials shall be considered as a through E3608.1.6. The supplemental electrode shall be
grounding electrode: bonded to one of the following:
1. Grounding electrodes of pipe or conduit shall not be 1. A rod, pipe, or plate electrode.
3
smaller than trade size / (metric designator 21) and, 2. A grounding electrode conductor.
4
where of iron or steel, shall have the outer surface 3. A grounded service-entrance conductor.
galvanized or otherwise metal-coated for corrosion
protection. 4. A nonflexible grounded service raceway.
2. Rod-type grounding electrodes of stainless steel and 5. A grounded service enclosure.
copper or zinc-coated steel shall be at least / inch Where multiple rod, pipe, or plate electrodes are installed
5
8
(15.9 mm) in diameter unless listed. [250.52(A)(5)] to meet the requirements of this section, they shall not be less
E3608.1.4.1 Installation. The rod and pipe electrodes than 6 feet (1829 mm) apart. [250.53(A)(2) and (A)(3)]
shall be installed such that at least 8 feet (2438 mm) of Exception: Where a single rod, pipe, or plate grounding
length is in contact with the soil. They shall be driven electrode has a resistance to earth of 25 ohms or less, the
to a depth of not less than 8 feet (2438 mm) except that, supplem electr sh no required.
where rock bottom is encountered, electrodes shall be [250.53(A)(2) Exception]
driven at an oblique angle not to exceed 45 degrees E3608.5 Aluminum electrodes. Aluminum electrodes shall
(0.79 rad) from the vertical or shall be buried in a not be permitted. [250.52(B)(2)]
trench that is at least 30 inches (762 mm) deep. The
upper end of the electrodes shall be flush with or below E3608.6 Metal underground gas piping system. A metal
ground level except where the above-ground end and underground gas piping system shall not be used as a ground-
the grounding electrode conductor attachment are pro- ing electrode. [250.52(B)(1)]
tected against physical damage. (250.53(G)] E3608.7 Pool, spa and hot tub structures and structural
E3608.1.5 Plate electrodes. A plate electrode that reinforcing steel. The structures and structural reinforcing
exposes not less than 2 square feet (0.186 m ) of surface to steel described in Section E4204.2, Items 1 and 2, shall not be
2
exterior soil shall be considered as a grounding electrode. used as a grounding electrode.
Electrodes of bare or electrically conductive coated iron or
1
steel plates shall be not less than / inch (6.4 mm) in thick-
4
ness. Solid, uncoated electrodes of nonferrous metal shall SECTION E3609
be not less than 0.06 inch (1.5 mm) in thickness. Plate BONDING
electrodes shall be installed not less than 30 inches (762 E3609.1 General. Bonding shall be provided where neces-
mm) below the surface of the earth. [250.52(A)(7)] sary to ensure electrical continuity and the capacity to con-
E3608.1.6 Other electrodes. In addition to the grounding duct safely any fault current likely to be imposed. (250.90)
electrodes specified in Sections E3608.1.1 through E3609.2 Bonding of equipment for services. The noncur-
E3608.1.5, other listed grounding electrodes shall be per- rent-carrying metal parts of the following equipment shall be
mitted. [250.52(A)(6)] effectively bonded together:
E3608.2 Bonding jumper. The bonding jumper(s) used to 1. Raceways or service cable armor or sheath that enclose,
connect the grounding electrodes together to form the contain, or support service conductors.
grounding electrode system shall be installed in accordance 2. Service enclosures containing service conductors,
with Sections E3610.2, and E3610.3, shall be sized in accor- including meter fittings, and boxes, interposed in the
dance with Section E3603.4, and shall be connected in the service raceway or armor. [250.92(A)]
manner specified in Section E3611.1. [250.53(C)] E3609.3 Bonding for communications systems. Communi-
E3608.3 Rod, pipe and plate electrode requirements. cations system bonding terminations shall be connected in
Where practicable, rod, pipe and plate electrodes shall be accordance with Section E3609.3.1 or E3609.3.2. (250.94)
embedded below permanent moisture level. Such electrodes
shall be free from nonconductive coatings such as paint or E3609.3.1 Intersystem bonding termination device. An
enamel. Where more than one such electrode is used, each intersystem bonding termination (IBT) for connecting

708 2018 INTERNATIONAL RESIDENTIAL CODE ®
Copyrighted © 2017 by, or licensed to, ICC (ALL RIGHTS RESERVED); licensed to UL, LLC pursuant to License Agreement with ICC. No further reproductions authorized or distribution authorized.
ANY UNAUTHROIZED REPRODUCTION OR DISTRIBUTION IS A VIOLATION OF THE FEDERAL COPYRIGHT ACT AND THE LICENSE AGREEMENT; AND SUBJECT TO CIVIL AND CRIMINAL PENALTIES THEREUNDER.