[Federal Register Volume 77, Number 63 (Monday, April 2, 2012)]
[Rules and Regulations]
[Pages 19525-19531]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2012-7610]
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DEPARTMENT OF AGRICULTURE
Rural Utilities Service
7 CFR Part 1728
Specification for 15 kV and 25 kV Primary Underground Power Cable
AGENCY: Rural Utilities Service, USDA.
ACTION: Final rule.
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SUMMARY: The Rural Utilities Service (RUS) is amending its regulations
regarding electric distribution specifications for 15kV and 25 kV
primary underground power cable. This rule will rescind Bulletin 50-70
(U-1), ``REA Specification for 15 kV and 25 kV Primary Underground
Power Cable,'' and codify the material which was formerly incorporated
by reference. The specifications and standards that appeared in the old
RUS Bulletin 50-70 (U-1) will be incorporated by reference and will
update the specifications for 15kV and 25kV underground power cable,
and provide RUS borrowers with specifications for 35 kV underground
power cable for use in 25 kV primary systems. These specifications
cover single-phase and multi-phase primary underground power cable
which RUS electric borrowers use to construct their rural underground
electric distribution systems.
DATES: This rule is effective May 2, 2012.
Incorporation by Reference: The incorporation by reference of
certain publications listed in this rule is approved by the Director of
the Federal Register as of May 2, 2012
FOR FURTHER INFORMATION CONTACT: Mr. Trung V. Hiu, Electrical Engineer,
Electric Staff Division, Distribution Branch, Rural Utilities Service,
United States Department of Agriculture, Room 1262-S, 1400 Independence
Avenue SW., Washington, DC 20250-1569. Telephone: (202) 720-1877. FAX:
(202) 720-7491. Email: [email protected].
SUPPLEMENTARY INFORMATION:
Executive Order 12866
This final rule is exempted from the Office of Management and
Budget (OMB) review for purposes of Executive Order 12866 and,
therefore, has not been reviewed by OMB.
Executive Order 12372
This final rule is excluded from the scope of Executive Order
12372, Intergovernmental Consultation, which may require consultation
with State and local officials. A notice of the final rule entitled
``Department Programs and Activities Excluded from Executive Order
12372,'' (50 FR 47034) exempted the Rural Utilities Service loans and
loan guarantees to form coverage under this order.
Executive Order 12988
This final rule has been reviewed under Executive Order 12988,
Civil Justice Reform. The Rural Utilities Service has determined that
this rule meets the applicable standards provided in section 3 of the
Executive Order. In
[[Page 19526]]
addition, all state and local laws and regulations that are in conflict
with this rule will be preempted. No retroactive effect will be given
to this rule and in accordance with section 212(e) of the Department of
Agriculture Reorganization Act of 1994 (7 U.S.C. 6912(e))
administrative appeal procedures, if any, must be exhausted before an
action against the Department or its agencies may be initiated.
Executive Order 13132
This final rule will not have substantial direct effects on the
States, on the relationship between the national government and the
States, or on distribution of power and responsibilities among the
various levels of government. Under Executive Order 13132, this rule
does not have sufficient federalism implications to require preparation
of a Federalism Assessment.
Regulatory Flexibility Act Certification
It has been determined that the Regulatory Flexibility Act is not
applicable to this rule since the Rural Utilities Service is not
required by 5 U.S.C. et seq. or any other provision of law to publish a
notice of proposed rulemaking with respect to the subject matter of
this final rule.
Information Collection and Recordkeeping Requirements
This final rule contains no additional information collection and
recordkeeping requirements and is cleared under control number 0572-
0131 pursuant to the Paperwork Reduction Act of 1995 (44 U.S.C. chapter
35, as amended).
Catalog of Federal Domestic Assistance
The program described by this final rule is listed in the Catalog
of Federal Domestic Assistance Programs under No. 10.850, Rural
Electrification Loans and Loan Guarantees. This catalog is available on
a subscription basis from the Superintendent of Documents, U.S.
Government Printing Office, Washington, DC 20402-9325, telephone number
(202) 512-1800.
Executive Order 12372
This final rule is excluded from the scope of Executive Order
12372, Intergovernmental Consultation, which may require consultation
with State and local officials. See the final rule related notice
titled ``Department Programs and Activities Excluded from Executive
Order 12372'' (50 FR 47034), advising that Rural Utilities Service
loans and loan guarantees are excluded from the scope of Executive
Order 12372.
Unfunded Mandates
This final rule contains no Federal Mandates (under the regulatory
provision of title II of the Unfunded Mandates Reform Act of 1995 [2
U.S.C. chapter 25]) for State, local, and tribal governments or the
private sector. Thus, this rule is not subject to the requirements of
sections 202 and 205 of the Unfunded Mandates Reform Act of 1995.
National Environmental Policy Act Certification
The Rural Utilities Service has determined that this final rule
will not significantly affect the quality of the human environment as
defined by the National Environmental Policy Act of 1969 (42 U.S.C.
4321 et seq.). Therefore, this action does not require an environmental
impact statement or assessment.
Background
RUS maintains a system of bulletins that contain construction
standards and specifications for materials and equipment which must be
complied with when system facilities are constructed by electric and
telecommunications borrowers in accordance with the loan contract.
These standards and specifications contain standard construction units
and material items and equipment units commonly used in electric and
telecommunications borrowers' systems.
RUS in conjunction with the Office of the Federal Register
determined that Bulletin 50-70 (U-1), ``REA Specification for 15 kV and
25 kV Primary Underground Power Cable,'' would be codified. The
material will now appear in 7 CFR 1728.204. Rescinding Bulletin 50-70
(U-1) and codifying the material in its entirety provides greater
convenience for RUS borrowers when searching for specifications and
standards requirements. Additionally, the specifications and standards
that appeared in the old RUS Bulletin 50-70 (U-1) will be incorporated
by reference in 1728.97 and will update the specifications for 15kV and
25kV underground power cable, and provide RUS borrowers with
specifications for 35 kV underground power cable for use in 25 kV
primary systems. These specifications cover single-phase and multi-
phase primary underground power cable which RUS electric borrowers use
to construct their rural underground electric distribution systems.
These changes provide standard requirements for 15kV and 25 kV single-
phase and multi-phase primary underground power cable with cross-linked
polyethylene with tree retardant or ethylene propylene rubber
insulation, concentric neutral, and insulating outer jacket and updates
the specifications for 15kV and 25 kV primary underground cable while
adding specifications for 35 kV primary underground power cable.
The following changes and updates are as follows:
1. Water blocking sealant would be required in all stranded
conductor cables.
2. The plain cross-linked polyethylene (XLP) would be removed and
be replaced by tree-retardant cross-linked polyethylene (TR-XLPE) as an
acceptable insulation material.
3. Nominal insulation thickness on 25 kV cable would be reduced
from 345 mils to 260 mils.
4. An optional semi-conducting jacketing material would be added to
the specification for cables of all three specified voltages. Cables
with semi-conducting jackets may be used by RUS borrowers in areas with
soil resistivity greater than 25 ohm-meter, in lieu of using cables
with an insulating jacket to help improve the effectiveness of system
grounding in locations of high soil resistivity.
Summary of Comments
A proposed rule entitled ``Specifications for Primary Underground
Power Cable,'' was published August 30, 2007, at 72 FR 50081, invited
interested parties to submit comments. The National Rural Electric
Cooperative Association Transmission and Distribution (NRECA T&D)
Engineering Underground Subcommittee and the cable manufacturers--
Prysmian Cables & Systems (PCS), Southwire, General Cable, Nexans
Energy, Hendrix Wire and Cable (HWC), submitted comments. No comments
from any other sources were received. The comments submitted by NRECA
represent the views of its members.
Comment: NRECA T&D suggested adding the abbreviations IEEE, LDPE,
LLDPE, MDPE and HDPE to the ``Abbreviations'' section.
Agency Response: RUS agrees with the recommendation and has revised
the final rule accordingly.
Comment: PCS suggested removing the word ``insulating'' as this
implies a voltage rating for the jacket. Jackets do not have a voltage
rating per the National Electrical Code (NEC).
Agency Response: RUS agrees with the recommendation and has revised
the final rule accordingly.
[[Page 19527]]
Comment: Southwire suggested updating the publication dates of
reference standards and adding ASTM B835-04, B836-00 (2005), B901-04,
B902-04a standards.
Agency Response: RUS agrees with the recommendation and has revised
the final rule accordingly.
Comment: Southwire, NRECA T&D, General Cable, and Nexans suggested
adding Insulated Cable Engineers Association, Inc. (ICEA) to the list
of addresses.
Agency Response: RUS agrees with the recommendation and has revised
the final rule accordingly.
Comment: General Cable suggested adding the address: IHS; 15
Inverness Way East; Englewood, CO 80112; Telephone: 800-854-7179; Web
Site: http://www. globe,ihs.com (7, section 3b, ``Availability of
Publications'').
Agency Response: RUS agrees with the recommendation and has revised
the final rule accordingly.
Comment: Southwire recommended adding compressed and compact round
stranded copper conductors using single input wire construction in
accordance with ASTM B902-4a and B835-04 to this section.
Agency Response: RUS agrees with the recommendation and has revised
the final rule accordingly.
Comment: PCS suggested correcting the ``R14'' in the first line to
``H14''. This was a typo.
Agency Response: RUS agrees with the recommendation and has revised
the final rule accordingly.
Comment: General Cable, Nexans Energy, PCS, and Southwire suggested
the following changes: Central aluminum phase conductors shall be one
of the following:
This part should be changed to 4d which would require the conductor
to be filled whether it be copper or aluminum. The requirement to fill
the conductor interstices so as not to allow moisture to migrate
through the conductor should be for both aluminum and copper conductor
and not just for aluminum conductor. Filling the strands of a conductor
is done to pick moisture out to the conductor and whereby limiting the
moisture that can migrate into the insulation.
Agency Response: RUS agrees with the recommendation and has revised
the final rule accordingly.
Comment: PCS suggested replacing the word ``moisture'' with the
word ``water''. The test protocol is a Water penetration test.
Agency Response: RUS agrees with the recommendation and has revised
the final rule accordingly.
Comment: All cable manufacturers recommended removing the
requirement for indent printing on a solid conductor. Requiring indent
print on solid conductors does not seem consistent with keeping the
interface of the conductor and extruded components smooth. Using indent
on a solid conductor will cause the surface of the conductor to have
some metal displacement and create irregularities on the conductor
surface. Indent printing on the center strand of a stranded conductor
is being used today on cables and this type of identification should be
limited to stranded conductor and not used on solid conductor use for
medium voltage cables.
Agency Response: RUS agrees with the recommendation and has revised
the final rule.
Comment: Conductor Shield, NRECA T&D suggested adding (for
discharge resistant EPR) after the first word ``insulating''--``The
void and protrusion limits on the conductor shield shall be in
compliance with ANSI/ICEA S-94-649'' as was done in the Insulation
Shield Section (or state the actual limits).
Agency Response: The RUS agrees with the recommendation and has
added ``The void and protrusion limits on the conductor shield shall be
in compliance with ANSI/ICEA S-94-649''.
Comment: PCS suggested replacing the words ``An insulating'' with
``A non-conducting''. This will align the wording with ANSI/ICEA S-94-
649 standard.
Agency Response: RUS agrees with the recommendation and has revised
the final rule.
Comment: Insulation, NRECA T&D suggested adding ``The void and
protrusion limits on the insulation shall be in compliance with ANSI/
ICEA S-94-649'' as was done in the Insulation Shield Section (or state
the actual limits).
Agency Response: RUS agrees with the recommendation and has added
``The void and protrusion limits on the conductor shield shall be in
compliance with ANSI/ICEA S-94-649''.
Comment: PCS suggested removing the words inside the parentheses
``(e.g., cross-linked polyethylene shield may be used with EPR
insulation)''. The term ``thermosetting polymeric layer'' sets forth
the requirement sufficiently. As a matter of technical clarification,
the insulation shield materials are not XLPE but are in fact a co-
polymer material. Polymeric layer is a good way to refer to these
materials.
Agency Response: RUS agrees with the recommendation and has revised
the final rule.
Comment: PCS stated there is no technical justification to have
different minimum stripping tensions for EPR and TRXLPE. This
requirement needs to be changed so both materials have the same minimum
tension of 3 pounds as required by the ANSI approved industry standard.
Agency Response: Stripping tensions values shall be 3 through 18
pounds (1.36 through 8.16 kg) for EPR discharge free and TR-XLPE
cables. Discharge resistant cables shall have strip tension of 0
through 18 pounds (0 through 8.16 kg).
Comment: General Cable suggested changing the requirement of
stripping tension for TR-XLPE cable to the industry standard of a
maximum of 24 lb. Limiting the maximum stripping tension to 18 lb will
cause quality cable to be rejected based on a difference of 6 lb. The
industry standards require that the cables be able to be stripped at
temperatures between -10c and 40c without tearing based on a defined
test procedure regardless of the actual stripping tension.
Agency Response: Stripping tensions values shall be 3 through 18
pounds (1.36 through 8.16 kg) for EPR discharge free and TR-XLPE
cables. Discharge resistant cables shall have strip tension of 0
through 18 pounds (0 through 8.16 kg).
Comment: HWC suggested the minimum strip tension should be 3 pounds
for both EPR and TR0XLPE discharge free cable designs as required by
the referenced ANSI/ICEA Standard. Specifying a difference without a
technical basis would only serve to provide a justified commercial
advantage.
Agency Response: Stripping tensions values shall be 3 through 18
pounds (1.36 through 8.16 kg) for EPR discharge free and TR-XLPE
cables. Discharge resistant cables shall have strip tension of 0
through 18 pounds (0 through 8.16 kg).
Comment: Nexans Energy suggested the minimum strip tension of 3
lbs. should be applicable to both EPR and TR-XLPE.
Agency Response: Stripping tensions values shall be 3 through 18
pounds (1.36 through 8.16 kg) for EPR discharge free and TR-XLPE
cables. Discharge resistant cables shall have strip tension of 0
through 18 pounds (0 through 8.16 kg).
Comment: PCS suggested the word ``uncoated'' in the beginning of
the second line should be removed as some manufacturers will only
provide flat
[[Page 19528]]
straps tin-coated and there is no technical reason to not allow this
construction.
Agency Response: RUS disagrees and its previous experience
indicates tin-coated neutral may accelerate corrosion at holidays. RUS
will not allow tin-coated neutral.
Comment: PCS suggested this paragraph to read as follows: ``The
jacket type shall be an Extruded-to-Fill Jacket that fills the area
between the concentric neutral wires and covers the wires to the proper
thickness. The jacket shall be free stripping. The jacket shall have
three red stripes longitudinally extruded into the jacket surface 120
degrees apart per ANSI/ICEA S-94-649.''
Agency Response: RUS disagrees and the current text is in an
acceptable format and remains unchanged.
Comment: PCS stated ICEA does a good job specifying the jacket
materials. ASTM has requirements that only pertain to base resins which
typically can not be measured on compounds received or have pertinence
to the performance of the jacket material in its intended environment.
The Extruded-to-Fill jacket materials are limited to LLDPE and LDPE.
The references to (insulating) and to the ASTM D1248 specification
should be removed. This paragraph should be changed to ``Nonconducting
jackets shall be LDPE or LLDPE compound meeting the requirements of
ANSI/ICEA S-94-649.''
Agency Response: RUS agrees with the recommendation and has revised
the final rule accordingly.
Comment: NRECA T&D suggested checking with Dow Chemical and/or
Borealis to confirm the vapor transmission rate of 2 g/m2/24 hours is
valid for current semi-conducting jacket compounds.
Agency Response: RUS has verified and confirmed with Dow Chemical
of the current physical properties specification of the DOW DHDA-7708
Black moisture vapor transmission rate at 38 degree C, 90% RH is 1.5
gms/m2/24 hrs (ASTME96).
Comment: PCS stated this paragraph indicates a maximum moisture
vapor transmission rate of 2 g/m\2\/24 hours at 38 [deg]C and 96%
relative humidity in accordance with ASTM E 96. They believe there is
no test data to support there are materials commercially available to
meet this maximum value. They suggest that this value be removed.
Agency Response: RUS has verified and confirmed with Dow Chemical
of the current physical properties specification of the DOW DHDA-7708
Black moisture vapor transmission rate at 38 degree C, 90% RH is 1.5
gms/m2/24 hrs (ASTME96).
Comment: ``Overall Outer Jacket'', paragraph a (3), Southwire
stated the requirement for maximum moisture transmission rate of 2 g/
m\2\/24 hours at 38 [deg]C (100 [deg] F) and 96% relative humidity in
accordance with ASTM E 96 does not agree with existing data sheets from
the material provider, Dow Chemical. Their product was tested at 90%
RH. Southwire suggested this requirement be verified with the material
supplier or deleted.
Agency Response: RUS has verified and confirmed with Dow Chemical
of the current physical properties specification of the DOW DHDA-7708
Black moisture vapor transmission rate at 38 degree C, 90% RH is 1.5
gms/m2/24 hrs (ASTME96).
Comment: ``Overall Outer Jacket'', paragraph a (3), Southwire
suggested the word ``maximum'' should be added to the first sentence--
Semi-conducting jackets shall have a maximum radial resistivity of 100
ohm-meter.
Agency Response: RUS agrees with the recommendation and has revised
the final rule accordingly.
Comment: NRECA T&D, General Cable, PCS, Nexans Energy, and
Southwire suggested deleting Dimensional Tolerances--this section come
from the old U-1 and ICEA S-94-649 has minimum and maximum tolerances
on each layer of the cable construction but not on the overall cable
core. There is an Appendix C in ICEA to calculate these tolerances and
they will vary greatly by conductor size and insulation thickness.
Agency Response: RUS agrees with the recommendation and has revised
the final rule accordingly.
Comment: General Cable suggested changing ``Partial Discharge
Tests'' to Discharge Tests: Manufacturers shall demonstrate that their
cable meets either the partial discharge test for Discharge Free cable
design or the Discharge Resistance test for Discharge Resistant cable
designs as required per ICEA S-94-649 and as described in b(1) or b(2)
of this bulletin.
Agency Response: RUS disagrees. The current text is acceptable.
Comment: Jacket tests, cable manufacturers suggested the (cold bend
test) requirement be omitted. Since polyethylene's (low, medium and
high density) have excellent cold temperature properties, there is no
need to do cold bend test. ICEA standards do not require a cold bend
test for these jacket materials for the reason stated above. Jacket
material such as Polyvinyl Chloride (PVC) and Chlorinated Polyethylene
(CPE) do require a cold bend test but are not allowed to be used in
this specification.
Agency Response: RUS agrees with the recommendation and has revised
the final rule accordingly.
Comment: HWC suggested that jacket type is only printed if the
jacket is semi-conducting as required by the referenced ANSI/ICEA
Standard.
Agency Response: RUS disagrees. The current text and format are
acceptable.
Comment: PCS stated the cable reel is not for protection but to
allow ease of handling and installation of the cable. They recommend
that the purchaser define the class of reels and reel covering material
that one want specified per NEMA WC26. The reel and covering should be
at the mutual agreement of the purchaser and the manufacturer.
Agency Response: RUS disagrees. The current text and requirement
are acceptable.
List of Subjects in 7 CFR Part 1728
Electric power, Incorporation by reference, Loan programs--energy,
Rural areas.
For the reasons set out in the preamble, 7 CFR part 1728 is amended
as follows:
PART 1728--ELECTRIC STANDARDS AND SPECIFICATIONS FOR MATERIALS AND
CONSTRUCTION
0
1. The authority citation for part 1728 continues to read as follows:
Authority: 7 U.S.C. 901 et seq., 7 U.S.C. 1921 et seq.; 7 U.S.C.
6941 et seq.
0
2. In Sec. 1728.97, redesignate paragraphs (e), (f), and (g) as
paragraphs (f), (h), and (i), respectively, revise paragraph (d), and
add new paragraphs (e) and (g) to read as follows:
Sec. 1728.97 Incorporation by reference of electric standards and
specifications.
* * * * *
(d) The American National Standards Institute/Insulated Cable
Engineers Association, Inc. (ANSI/ICEA) makes the following material
available for purchase from Global Engineering Documents for a fee at
the following address: IHS Global Engineering Documents, 15 Inverness
Way East, Englewood, CO 80112, Phone: (303) 397-7956; (800)-854-7179,
Fax: (303) 397-2740, email: ihs.com">global@ihs.com, Web site: http://global.ihs.com.
(1) ANSI/ICEA S-94-649-2004--Standard for Concentric Neutral Cables
Rated 5 Through 46 KV (ANSI/ICEA S-94-649-2004), approved September 20,
2005, incorporation by reference approved for Sec. 1728.204.
[[Page 19529]]
(2) ANSI/ICEA T-31-610-2007--Test Method for Conducting
Longitudinal Water Penetration Resistance Tests on Blocked Conductors
(ANSI/ICEA T-31-610-2007), approved October 31, 2007, incorporated by
reference approved for Sec. 1728.204.
(e) Copies of American Society for Testing and Materials (ASTM)
publications referenced in this specification can be obtained from ASTM
for a fee at the following address: ASTM, 100 Barr Harbor Drive, West
Conshohocken, PA 19428-2959, Telephone: (610) 832-9585, Web site:
http://astm.org.
(1) ASTM B 3-01 (Reapproved 2007)--Standard Specification for Soft
or Annealed Copper Wire, (ASTM B 3-01) approved March 15, 2007,
incorporated by reference approved for Sec. 1728.204.
(2) ASTM B 8-04--Standard Specification for Concentric-Lay-Stranded
Copper Conductors, Hard, Medium-Hard, or Soft (ASTM B 8-04), approved
April 1, 2004, incorporated by reference approved for Sec. 1728.204.
(3) ASTM B 230/B 230M-07--Standard Specification for Aluminum 1350-
H19 Wire for Electrical Purposes (ASTM B 230/B 230M-07), approved March
15, 2007, incorporated by reference approved for Sec. 1728.204.
(4) ASTM B 231/B 231M-04--Standard Specification for Concentric-
Lay-Stranded Aluminum 1350 Conductors (ASTM B 231/B 231M-04), approved
April 1, 2004, incorporated by reference approved for Sec. 1728.204.
(5) ASTM B 400-08--Standard Specification for Compact Round
Concentric-Lay-Stranded Aluminum 1350 Conductors (ASTM B 400-08),
approved September 1, 2008, incorporated by reference approved for
Sec. 1728.204.
(6) ASTM B 496-04--Standard Specification for Compact Round
Concentric-Lay-Stranded Copper Conductors (ASTM B 496-04), approved
April 1, 2004, incorporated by reference approved for Sec. 1728.204.
(7) ASTM B 609/B 609M-99--Standard Specification for Aluminum 1350
Round Wire, Annealed and Intermediate Tempers, for Electrical Purposes
(ASTM B 609/B 609M-99), approved April 1, 2004, incorporated by
reference approved for Sec. 1728.204.
(8) ASTM B 786-08--Standard Specification for 19 Wire Combination
Unilay-Stranded Aluminum 1350 Conductors for Subsequent Insulation
(ASTM B 786-08), approved September 1, 2008, incorporated by reference
approved for Sec. 1728.204.
(9) ASTM B 787/B 787M-04--Standard Specification for 19 Wire
Combination Unilay-Stranded Copper Conductors for Subsequent Insulation
(ASTM B 787/B 787M-04), approved September 1, 2004, incorporated by
reference approved for Sec. 1728.204.
(10) ASTM B 835-04--Standard Specification for Compact Round
Stranded Copper Conductors Using Single Input Wire Construction (ASTM B
835-04), approved September 1, 2004, incorporated by reference approved
for Sec. 1728.204.
(11) ASTM B902-04a--Standard Specification for Compressed Round
Stranded Copper Conductors, Hard, Medium-Hard, or Soft Using Single
Input Wire Construction (ASTM B902-04a), approved September 1, 2004,
incorporated by reference approved for Sec. 1728.204.
(12) ASTM D 1248-05--Standard Specification for Polyethylene
Plastics Extrusion Materials for Wire and Cable (ASTM D 1248-05),
approved March 1, 2005, incorporated by reference approved for Sec.
1728.204.
(13) ASTM D 2275-01 (Reapproved 2008)--Standard Test Method for
Voltage Endurance of Solid Electrical Insulating Materials Subjected to
Partial Discharges (Corona) on the Surface (ASTM D 2275-01), approved
May 1, 2008, incorporated by reference approved for Sec. 1728.204.
(14) ASTM E 96/E 96M-05--Standard Test Methods for Water Vapor
Transmission of Materials (ASTM E 96/E 96M-05), approved May 1, 2005,
incorporated by reference approved for Sec. 1728.204.
* * * * *
(g) The following material is available from the Insulated Cable
Engineers Association (ICEA) and may be purchased from Global
Engineering Documents for a fee at the following address: IHS Global
Engineering Documents, 15 Inverness Way East, Englewood, CO 80112,
Phone: (303) 397-7956; (800)-854-7179, Fax: (303) 397-2740, email:
ihs.com">global@ihs.com, Web site: http://global.ihs.com.
(1) ICEA T-32-645-93--Guide for Establishing Compatibility of
Sealed Conductor Filler Compounds with Conducting Stress Control
Materials (ICEA T-32-645-93), approved February 1993, incorporated by
reference approved for Sec. 1728.204.
(2) [Reserved]
0
3. Add and reserve new Sec. 1728.203 to read as follows:
Sec. 1728.203 [Reserved]
0
4. Add new Sec. 1728.204 to read as follows:
Sec. 1728.204 Electric standards and specifications for materials and
construction.
(a) General specifications. This section details requirements for
15 and 25 kV single phase, V-phase, and three-phase power cables for
use on 12.5/7.2 kV (15 kV rated) and 24.9/14.4 kV (25 kV rated)
underground distribution systems with solidly multi-grounded neutral.
Cable complying with this specification shall consist of solid or
strand-filled conductors which are insulated with tree-retardant cross-
linked polyethylene (TR-XLPE) or ethylene propylene rubber (EPR), with
concentrically wound copper neutral conductors covered by a
nonconducting or semiconducting jacket. 35 kV rated cables may be used
in 24.9/14.4 kV application where additional insulation is desired.
(1) The cable may be used in single-phase, two (V)-phase, or three-
phase circuits.
(2) Acceptable conductor sizes are: No. 2 AWG (33.6 mm\2\) through
1000 kcmil (507 mm\2\) for 15 kV cable, No. 1 AWG (42.4 mm\2\) through
1000 kcmil (507 mm\2\) for 25 kV, and 1/0 (53.5 mm\2\) through 1000
kcmil (507 mm\2\) for 35 kV cable.
(3) Except where provisions therein conflict with the requirements
of this specification, the cable shall meet all applicable provisions
of ANSI/ICEA S-94-649-2004 (incorporated by reference in Sec.
1728.97). Where provisions of the ANSI/ICEA specification conflict with
this section, Sec. 1728.204 shall apply.
(b) Definitions. As used in this section:
Agency refers to the Rural Utilities Service (RUS), an agency of
the United States Department of Agriculture's (USDA), hereinafter
referred to as the Agency.
EPR Insulating Compound is a mixture of ethylene propylene base
resin and selected ingredients.
TR-XLPE Insulating Compound is a tree retardant crosslinked
polyethylene (TR-XLPE) insulation compound containing an additive, a
polymer modification filler, which helps to retard the growth of
electrical trees in the compound.
(c) Phase conductors. (1) Central phase conductors shall be copper
or aluminum as specified by the borrower within the limit of Sec.
1728.204(a)(2).
(2) Central copper phase conductors shall be annealed copper in
accordance with ASTM B 3-01 (incorporated by reference in Sec.
1728.97). Concentric-lay-stranded phase conductors shall conform to
ASTM B 8-04 (incorporated by reference in Sec. 1728.97) for Class B
stranding. Compact round concentric-
[[Page 19530]]
lay-stranded phase conductors shall conform to ASTM B 496-04
(incorporated by reference in Sec. 1728.97). Combination unilay
stranded phase conductors shall conform to ASTM B 787/B 787M-04
(incorporated by reference in Sec. 1728.97). Compact round atranded
copper conductors using single input wire construction shall conform to
ASTM B835-04 (incorporated by reference in Sec. 1728.97). Compressed
round stranded copper conductors, hard, medium-hard, or soft using
single input wire construction shall conform to ASTM B902-04a
(incorporated by reference in Sec. 1728.97). If not specified,
stranded phase conductors shall be Class B stranded.
(3) Central aluminum phase conductors shall be one of the
following:
(i) Solid: Aluminum 1350 H12 or H22, H14 or H24, H16 or H26, in
accordance with ASTM B 609/B 609M-99 (incorporated by reference in
Sec. 1728.97).
(ii) Stranded: Aluminum 1350 H14 or H24, H142 or H242, H16, or H26,
in accordance with ASTM B 609/B 609M-99 (incorporated by reference in
Sec. 1728.97) or Aluminum 1350-H19 in accordance with ASTM B 230/B
230M-07 (incorporated by reference in Sec. 1728.97). Concentric-lay-
stranded (includes compacted and compressed) phase conductors shall
conform to ASTM B 231/B 231M-04 (incorporated by reference in Sec.
1728.97) for Class B stranding. Compact round concentric-lay-stranded
phase conductors shall conform to ASTM B 400-08 (incorporated by
reference in Sec. 1728.97). Combination unilay stranded aluminum phase
conductors shall conform to ASTM B 786-08 (incorporated by reference in
Sec. 1728.97). If not specified, stranded phase conductors shall be
class B stranded.
(4) The interstices between the strands of stranded conductors
shall be filled with a material designed to fill the interstices and to
prevent the longitudinal migration of water that might enter the
conductor. This material shall be compatible with the conductor and
conductor shield materials. The surfaces of the strands that form the
outer surface of the stranded conductor shall be free of the strand
fill material. Compatibility of the strand fill material with the
conductor shield shall be tested and shall be in compliance with ICEA
T-32-645-93 (incorporated by reference in Sec. 1728.97). Water
penetration shall be tested and shall be in compliance with ANSI/ICEA
T-31-610-2007 (incorporated by reference in Sec. 1728.97).
(5) The center strand of stranded conductors shall be indented with
the manufacturer's name and year of manufacture at regular intervals
with no more than 12 inches (0.3 m) between repetitions.
(d) Conductor shield (stress control layer). A non-conducting (for
discharge resistant EPR) or semi-conducting shield (stress control
layer) meeting the applicable requirements of ANSI/ICEA S-94-649-2004
(incorporated by reference in Sec. 1728.97) shall be extruded around
the central conductor. The minimum thickness at any point shall be in
accordance with ANSI/ICEA S-94-649-2004. The void and protrusion limits
on the conductor shield shall be in compliance with ANSI/ICEA S-94-649-
2004. The shield shall have a nominal operating temperature equal to,
or higher than, that of the insulation.
(e) Insulation. (1) The insulation shall conform to the
requirements of ANSI/ICEA S-94-649-2004 (incorporated by reference in
Sec. 1728.97) and may either be tree retardant cross-linked
polyethylene (TR-XLPE) or ethylene propylene rubber (EPR), as specified
by the borrower. The void and protrusion limits on the insulation shall
be in compliance with ANSI/ICEA S-94-649-2004.
(2) The thickness of insulation shall be as follows:
----------------------------------------------------------------------------------------------------------------
Cable rated voltage Nominal thickness Minimum thickness Maximum thickness
----------------------------------------------------------------------------------------------------------------
15 kV............................. 220 mils (5.59 mm)... 210 mils (5.33 mm)... 250 mils (6.35 mm).
25 kV............................. 260 mils (6.60 mm)... 245 mils (6.22 mm)... 290 mils (7.37 mm).
35 kV............................. 345 mils (8.76 mm)... 330 mils (8.38 mm)... 375 mils (9.53 mm).
----------------------------------------------------------------------------------------------------------------
(f) Insulation shield. (1) A semi-conducting thermosetting
polymeric layer meeting the requirements of ANSI/ICEA S-94-649-2004
(incorporated by reference in Sec. 1728.97) shall be extruded tightly
over the insulation to serve as an electrostatic shield and protective
covering. The shield compound shall be compatible with, but not
necessarily the same material composition as, that of the insulation
(e.g., cross-linked polyethylene shield may be used with EPR
insulation). The void and protrusion limits on the semi-conducting
shields shall be in compliance with the ANSI/ICEA S-94-649-2004.
(2) The thickness of the extruded insulation shield shall be in
accordance with ANSI/ICEA S-94-649-2004 (incorporated by reference in
Sec. 1728.97).
(3) The shield shall be applied such that all conducting material
can be easily removed without the need for externally applied heat.
Stripping tension values shall be 3 through 18 pounds (1.36 through
8.16 kg) for TR-XLPE and EPR discharge free cables. Discharge resistant
cables shall have strip tension of 0 through 18 pounds (0 through 8.16
kg).
(4) The insulation shield shall meet all applicable tests of ANSI/
ICEA S-94-649-2004 (incorporated by reference in Sec. 1728.97).
(g) Concentric neutral conductor. (1) Concentric neutral conductor
shall consist of annealed round, uncoated copper wires in accordance
with ASTM B 3-01 (incorporated by reference in Sec. 1728.97) and shall
be spirally wound over the shielding with uniform and equal spacing
between wires. The concentric neutral wires shall remain in continuous
intimate contact with the extruded insulation shield. Full neutral is
required for single phase and \1/3\ neutral for three phase
applications unless otherwise specified. The minimum wire size for the
concentric neutral is 16 AWG (1.32 mm\2\).
(2) When a strap neutral is specified by the borrower, the neutral
shall consist of uncoated copper straps applied concentrically over the
insulation shield with uniform and equal spacing between straps and
shall remain in intimate contact with the underlying extruded
insulation shield. The straps shall not have sharp edges. The thickness
of the flat straps shall be not less than 20 mils (0.5 mm).
(h) Overall outer jacket. (1) An electrically nonconducting
(insulating) or semi-conducting outer jacket shall be applied directly
over the concentric neutral conductors.
(2) The jacket material shall fill the interstice area between
conductors, leaving no voids. The jacket shall be free stripping. The
jacket shall have three red stripes longitudinally extruded into the
jacket surface 120[deg] apart.
(3) Nonconducting jackets shall consist of low density, linear low
density, medium density, or high density HMW black polyethylene
[[Page 19531]]
(LDPE, LLDPE, MDPE, HDPE) compound meeting the requirements of ANSI/
ICEA S-94-649-2004 (incorporated by reference in Sec. 1728.97) and
ASTM D 1248-05 (incorporated by reference in Sec. 1728.97) for Type I,
Class C, Category 4 or 5, Grade J3 before application to the cable.
Polyvinyl chloride (PVC) and chlorinated polyethylene (CPE) jackets are
not acceptable.
(4) Semi-conducting jackets shall have a maximum radial resistivity
of 100 ohm-meter and a maximum moisture vapor transmission rate of 1.5
g/m\2\/24 hours at 38[deg] C (100[deg] F) and 90 percent relative
humidity in accordance with ASTM E 96/E96M-05 (incorporated by
reference in Sec. 1728.97).
(5) The minimum thickness of the jacket over metallic neutral wires
or straps shall comply with the thickness specified in ANSI/ICEA S-94-
649-2004 (incorporated by reference in Sec. 1728.97).
(i) Tests. (1) As part of a request for Agency consideration for
acceptance and listing, the manufacturer shall submit certified test
data results to the Agency that detail full compliance with ANSI/ICEA
S-94-649-2004 (incorporated by reference in Sec. 1728.97) for each
cable design.
(i) Test results shall confirm compliance with each of the material
tests, production sampling tests, tests on completed cable, and
qualification tests included in ANSI/ICEA S-94-649-2004 (incorporated
by reference in Sec. 1728.97).
(ii) The testing procedure and frequency of each test shall be in
accordance with ANSI/ICEA S-94-649-2004 (incorporated by reference in
Sec. 1728.97).
(iii) Certified test data results shall be submitted to the Agency
for any test, which is designated by ANSI/ICEA S-94-649-2004
(incorporated by reference in Sec. 1728.97) as being ``for Engineering
Information Only,'' or any similar designation.
(2) Partial discharge tests. Manufacturers shall demonstrate that
their cable is not adversely affected by excessive partial discharge.
This demonstration shall be made by completing the procedures described
in paragraphs (i)(2)(i) and (i)(2)(ii) of this section.
(i) Each shipping length of completed cable shall be tested and
have certified test data results available indicating compliance with
the partial discharge test requirements in ANSI/ICEA S-94-649-2004
(incorporated by reference in Sec. 1728.97).
(ii) Manufacturers shall test production samples and have available
certified test data results indicating compliance with ASTM D 2275-01
(incorporated by reference in Sec. 1728.97) for discharge resistance
as specified in the ANSI/ICEA S-94-649-2004 (incorporated by reference
in Sec. 1728.97). Samples of insulated cable shall be prepared by
either removing the overlying extruded insulation shield material, or
using insulated cable before the extruded insulation shield material is
applied. The sample shall be mounted as described in ASTM D 2275-01 and
shall be subjected to a voltage stress of 250 volts per mil of nominal
insulation thickness. The sample shall support this voltage stress, and
not show evidence of degradation on the surface of the insulation for a
minimum of 100 hours. The test shall be performed at least once on each
50,000 feet (15,240 m) of cable produced, or major fractions thereof,
or at least once per insulation extruder run.
(3) Jacket tests. Tests described in paragraph (i)(3)(i) of this
section shall be performed on cable jackets from the same production
sample as in paragraphs (i)(2)(i) and (i)(2)(ii) of this section.
(i) A Spark Test shall be performed on nonconducting jacketed cable
in accordance with ANSI/ICEA S-94-649-2004 (incorporated by reference
in Sec. 1728.97) on 100 percent of the completed cable prior to its
being wound on shipping reels. The test voltage shall be 4.5 kV AC for
cable diameters <1.5 inches and 7.0 kV for cable diameters >1.5 inches,
and shall be applied between an electrode at the outer surface of the
nonconducting (insulating) jacket and the concentric neutral for not
less than 0.15 second.
(ii) [Reserved]
(4) Frequency of sample tests shall be in accordance with ANSI/ICEA
S-94-649-2004 (incorporated by reference in Sec. 1728.97).
(5) If requested by the borrower, a certified copy of the results
of all tests performed in accordance with this section shall be
furnished by the manufacturer on all orders.
(j) Miscellaneous. (1) All cable provided under this specification
shall have suitable markings on the outer surface of the jacket at
sequential intervals not exceeding 2 feet (0.61 m). The label shall
indicate the name of the manufacturer, conductor size, type and
thickness of insulation, center conductor material, voltage rating,
year of manufacture, and jacket type. There shall be no more than 6
inches (0.15 m) of unmarked spacing between texts label sequence. The
jacket shall be marked with the symbol required by Rule 350G of the
National Electrical Safety Code and the borrower shall specify any
markings required by local safety codes. This is in addition to
extruded red stripes required in this section.
(2) Watertight seals shall be applied to all cable ends to prevent
the entrance of moisture during transit or storage. Each end of the
cable shall be firmly and properly secured to the reel.
(3) Cable shall be placed on shipping reels suitable for protecting
it from damage during shipment and handling. Reels shall be covered
with a suitable covering to help provide physical protection to the
cable.
(4) A durable label shall be securely attached to each reel of
cable. The label shall indicate the purchaser's name and address,
purchase order number, cable description, reel number, feet of cable on
the reel, tare and gross weight of the reel, and beginning and ending
sequential footage numbers.
Dated: March 8, 2012.
Jonathan Adelstein,
Administator, Rural Utilities Service.
[FR Doc. 2012-7610 Filed 3-30-12; 8:45 am]
BILLING CODE P