September 07, 2010
September 07, 2010
TRANSMISSION MATERIALS STANDARD SPECIFICATION
10-TMSS-05, Rev. 01
TABLE OF CONTENTS
1.0
SCOPE
2.0
CROSS REFERENCES
3.0
APPLICABLE CODES AND STANDARDS
4.0
DESIGN AND CONSTRUCTION REQUIREMENTS
4.1
4.2
4.3
4.4
4.5
4.6
4.7
General
Ratings
Materials
Fabrication
Diameter and Permissible Variations
Reel Design
Markings
5.0
TESTS
6.0
DATA SCHEDULE
10TMSS05R01/MSO
Date of Approval: September 07, 2010
PAGE NO. 2 OF 11
TRANSMISSION MATERIALS STANDARD SPECIFICATION
1.0
10-TMSS-05, Rev. 01
SCOPE
This Transmission Material Standard Specification (TMSS) specifies the minimum technical
requirements for design, engineering, manufacture, inspection, testing and performance of
Bare Copper-Clad Steel Grounding Conductor and Ground Rod intended to be used for the
grounding of transmission line structures in the Transmission System of Saudi Electricity
Company (SEC), Saudi Arabia.
2.0
CROSS REFERENCES
This Material Standard Specification shall be read in conjunction with the latest revision of
SEC General Specification No. 01-TMSS-01, titled "General Requirements for All
Equipment/Materials" which shall be considered as an integral part of this TMSS.
This TMSS shall also be read in conjunction with SEC Purchase Order or Contract
Schedules for project, as applicable.
3.0
APPLICABLE CODES AND STANDARDS
The latest amendments/revision of the following Code and Standard shall be applicable for
the equipment/material covered in this TMSS. In case of conflict, the vendor/manufacturer
may propose equipment/material conforming to Industry Code and Standard other than that
quoted hereunder without jeopardizing the requirements of this TMSS.
ASTM B910/B910M Standard Specification for Annealed Copper-Clad Steel Wire
4.0
DESIGN AND CONSTRUCTION REQUIREMENTS
4.1
General
4.1.1 The copper-clad steel grounding conductor and copper-clad steel ground rods
shall be of manufacturer's standard design and shall meet or exceed the
requirements of this Specification in all respects.
4.1.2 The copper-clad steel grounding conductor shall be made from bare round
annealed copper-clad steel wires conforming to ASTM B910/B910M.
4.1.3 The service conditions referenced in 01-TMSS-01 shall be regarded as the
basis of design criteria.
4.1.4 Manufacturer's drawings, as required in 01-TMSS-01 shall show the outline
of the copper-clad steel grounding conductor and copper-clad steel ground
rod together with all pertinent dimensions. Any variations in these dimensions
due to manufacturing tolerances shall be indicated.
10TMSS05R01/MSO
Date of Approval: September 07, 2010
PAGE NO. 3 OF 11
TRANSMISSION MATERIALS STANDARD SPECIFICATION
4.2
10-TMSS-05, Rev. 01
Ratings
4.2.1 The copper-clad steel grounding conductor shall conform to the requirements
of Table 01 below:
Table 01: Ratings and characteristics of copper-clad steel grounding conductor
Conductor Size
Designation
AWG
7 No. 10
7 No. 9
7 No. 8
7 No. 7
7 No. 6
7 No. 5
7 No. 4
19 No. 8
19 No. 7
19 No. 6
19 No. 5
Nominal Diameter
Overall
Individual
Wire
(mm)
7.77
8.71
9.78
11.00
12.34
13.87
15.57
16.31
18.31
20.57
23.11
(mm)
2.588
2.906
3.264
3.665
4.115
4.620
5.189
3.264
3.665
4.115
4.620
Nominal
Total
Cross-Section
(mm²)
36.83
46.44
58.57
73.87
93.10
117.42
148.04
158.97
200.45
252.71
318.71
Minimum
Rated
Tensile
Strength
Max. DC
Resistance
at 20°C
(kN)
9.15
11.5
14.54
18.34
23.13
29.14
36.77
39.45
49.79
62.77
79.10
(Ohm/km)
1.244
0.9865
0.7820
0.6202
0.4920
0.3903
0.3094
0.2892
0.2294
0.1819
0.1443
Notes:
i.
The maximum DC Resistance at 20oC value is based on minimum individual
wire diameter and minimum conductivity of 39.21 % corresponding to a
resistivity of 0.0440 ohm mm2/m.
ii.
The tensile load is taken as ninety percent (90%) of the sum of the tensile
loads of the individual wires and is based on minimum tensile strength of 276
N/mm2 as referred in ASTM B910/B910M.
4.2.2 The required size and diameter of copper-clad steel grounding conductor shall
be specified in the Data Schedule.
4.2.3 The copper-clad steel ground rods shall have a nominal diameter of 16mm
(5/8 inches) and 19mm (3/4 inches) with a minimum length of 3 meter. The
ground rods shall be of sectional type equipped with suitable couplings and
driving studs. The required diameter of the ground rod shall be specified in
the Data Schedule.
4.3
Materials
4.3.1 The copper-clad wire shall consist of a core of homogeneous open-hearth,
electric-furnace, or basic-oxygen steel with a continuous outer cladding of
copper thoroughly bonded to the core throughout. The copper-clad wire shall
be free from copper discontinuities and all imperfections not consistent with
good commercial practice.
10TMSS05R01/MSO
Date of Approval: September 07, 2010
PAGE NO. 4 OF 11
TRANSMISSION MATERIALS STANDARD SPECIFICATION
10-TMSS-05, Rev. 01
4.3.2 The nominal conductivity of copper-clad steel wire shall be 40% IACS
(International Annealed Copper Standard).
4.3.3 The electrical resistivity of copper-clad steel wire at a temperature of 20ºC
shall not exceed 0.0440 ohm mm2/m.
4.3.4 All wires in the grounding conductor shall be of the same grade and quality.
4.3.5 The ground rods shall be made from high-strength steel (high carbon steel).
Pure electrolytic copper shall be uniformly molecularly bonded onto the core
to ensure corrosion resistance and eliminate electrolytic action. The steel core
shall have sufficient rigidity for easy driving with hammer or mechanical
drivers.
4.4
Fabrication
4.4.1 The copper-clad steel grounding conductors shall be constructed in
conventional concentric-lay-stranded type.
4.4.2 The copper-clad steel grounding conductors shall have left-hand lay and the
preferred lay is 13.5 times the diameter of that layer, but the pitch of the
strand shall be neither less than 10 nor more than 16 times this diameter.
4.4.3 All copper-clad steel wires in the conductor shall lie naturally in their true
positions in the completed conductor. They shall remain in position when the
conductor is cut at any point and shall permit re-stranding by hand after being
forcibly unraveled at the end of the conductor.
4.4.4 Joints or splices may be made in the finished individual copper-clad steel
wires composing concentric- lay-stranded conductor but these splices shall
not decrease the strength of the finished conductor below the minimum
breaking strength specified in Table 01.
4.4.5 These joints or splices shall not be closer than 15 meters to any other joint in
the same layer in the conductor.
4.4.6 The type of joints or splices in individual copper-clad steel wires shall be of
weld-annealed joints made by electric butt welding.
4.5
Diameter and Permissible Variations
4.5.1 The actual diameter of the copper-clad steel wires forming the conductor shall
not vary from the specified diameter by more than ± 1.5% expressed to the
nearest 0.003 mm.
4.5.2 The cross sectional area of the completed conductor shall not be less than
98% of the area specified. The cross sectional area of a conductor shall be
considered to be the sum of the cross-sectional areas of its component wires
at any section when measured perpendicularly to their individual axis.
10TMSS05R01/MSO
Date of Approval: September 07, 2010
PAGE NO. 5 OF 11
TRANSMISSION MATERIALS STANDARD SPECIFICATION
10-TMSS-05, Rev. 01
4.5.3 The minimum copper thickness due to eccentricity shall not be less than 5%
of the individual wire diameter (10% of the wire radius) as shown in
Table 02:
Table 02: Minimum copper thickness
Nominal
Individual Wire Diameter
(mm)
2.588
2.906
3.264
3.665
4.115
4.620
5.189
Minimum
Copper Thickness
(mm)
0.1294
0.1453
0.1632
0.1832
0.2057
0.2310
0.2594
4.5.4 The minimum thickness of copper for copper-clad steel ground rod shall not
be less than 0.25 mm at any point.
4.5.5 The actual diameter of the copper-clad steel ground rod shall not be less than
14.3mm and 17.1mm (unthreaded) for 16mm and 19mm nominal diameter
ground rods respectively.
4.6
Reel Design
4.6.1
Reel shall be of non-returnable wood.
4.6.2 The length of copper-clad steel grounding conductor per reel shall be 2000
meters with a permissible variation of ±5%, unless otherwise different lengths
are required as per actual site requirements or as agreed between SEC and the
manufacturer.
4.7
Markings
4.7.1 Each end of the copper-clad steel grounding conductor in the reel shall bear a
non-corroding tag identifying the following:
a.
b.
c.
d.
e.
Grade of grounding conductor
Diameter/Size of grounding conductor
Average Breaking Strength
Length of grounding conductor (on the one end only)
Stranding
4.7.2 Each reel shall be stenciled to show all information under paragraph 4.7.1
plus additional information as follows:
a.
b.
10TMSS05R01/MSO
Manufacturer's Name and Country of Origin
Year of Manufacture
Date of Approval: September 07, 2010
PAGE NO. 6 OF 11
TRANSMISSION MATERIALS STANDARD SPECIFICATION
c.
d.
e.
f.
g.
h.
i.
j.
4.7.3
5.0
10-TMSS-05, Rev. 01
Serial Number
Size of Reel
Gross Weight
SEC Purchase Order Number/Contract Number.
SEC Material Item Number
Consignee Address
Direction of Rolling
10-TMSS-05, Rev.0
All markings shall appear on both sides of the reel.
TESTS
All test results shall be provided for review and acceptance by SEC.
5.1
Tests for electrical and physical properties of copper-clad steel wires
composing concentric-lay-stranded conductors made from copper-clad steel
wire shall be made before stranding.
5.2
The routine test shall not be required after stranding.
5.3
The copper-clad steel wire shall withstand without fracture not less than 20
torsions in a length equivalent to 100 times the nominal diameter of the
specimen. The specimen shall be twisted by rotating on the wires at a rate of
approximately 15 twists per minute in the same direction until fracture occurs.
5.4
The copper-clad steel wire after twisting to destruction shall not reveal any
seams, pits, slivers or other imperfection of sufficient magnitude to indicate
inherent defects or imperfections. Examination of the wire at the break with the
unaided eye shall show no separation of the copper from the steel.
5.5
The electrical resistivity of the material shall be determined in accordance with
ASTM B193 Test Method for Resistivity of Electrical Conductor Materials.
5.6
Elongation shall be measured by means of an extensometer suitable for
measuring elongation in 250 mm in accordance with the testing requirements
specified in ASTM B910/B910M. It shall be attached to the test specimen at a
tension load of approximately ten percent (10%) of rated strength, and shall be
recorded as zero length.
The elongation shall be observed while applying tension load to the specimen
and the reading shall be taken when fracture occurs. The elongation of the
specimen shall be not less than fifteen percent (15%).
The tests shall be disregarded, if the fracture occurs in or at the gripping jaws
of the machine and the extensometer shows a reading less than fifteen percent
(15%).
10TMSS05R01/MSO
Date of Approval: September 07, 2010
PAGE NO. 7 OF 11
TRANSMISSION MATERIALS STANDARD SPECIFICATION
5.7
10-TMSS-05, Rev. 01
If upon testing a sample from any reel of wire, the results do not conform to the
tensile requirements prescribed in Table 1 and the elongation of specimen in
Clause 5.6, two additional samples shall be tested and the average of the two
tests shall determine the acceptance or rejection of the reel of wire.
10TMSS05R01/MSO
Date of Approval: September 07, 2010
PAGE NO. 8 OF 11
TRANSMISSION MATERIALS STANDARD SPECIFICATION
6.0
10-TMSS-05, Rev. 01
DATA SCHEDULE
BARE COPPER-CLAD STEEL GROUNDING CONDUCTOR AND GROUND ROD
SEC Enquiry No.
Date:
SEC Purchase Order
No.
or Contract No.
Date:
SEC PTS No./Project Title with J.O. No.
REFERENCE
SECTION NO.
3.0
DESCRIPTION
'A'
'B'
'C'
APPLICABLE CODES AND STANDARDS
ASTM B910/B910M
*
4.0
DESIGN AND CONSTRUCTION REQUIREMENTS
4.2.2
Copper-Clad Steel Grounding Conductor
AWG Size
Nominal Cross-Section (mm²)
Overall Diameter (mm)
Minimum Tensile Strength (kN)
*
D.C. Resistance at 20°C (Ω/km)
*
'A'- SEC SPECIFIED DATA/PARAMETERS
'B'- BIDDER/SUPPLIER/VENDOR/CONTRACTOR PROPOSED DATA/PARAMETERS
'C'- REMARKS SUPPORTING THE PROPOSED DEVIATION IN COLUMN 'B'
(*)- DATA/PARAMETERS TO BE PROVIDED/PROPOSED BY THE BIDDER/SUPPLIER/
VENDOR/CONTRACTOR IN COLUMN 'B'
10TMSS05R01/MSO
Date of Approval: September 07, 2010
PAGE NO. 9 OF 11
TRANSMISSION MATERIALS STANDARD SPECIFICATION
6.0
10-TMSS-05, Rev. 01
DATA SCHEDULE
BARE COPPER-CLAD STEEL GROUNDING CONDUCTOR AND GROUND ROD
REFERENCE
SECTION NO.
4.2.3
DESCRIPTION
'B'
'C'
Copper-Clad Steel Ground Rod
Nominal Diameter (mm)
16 or 19
Actual Diameter (mm)
14.3 or 17.1
Minimum Length (mm)
3,000
4.3
Conductivity of Annealed Copper-Clad
Steel Wire (% IACS)
4.4
Direction of Lay
4.5
Minimum Copper Thickness for:
40
left hand
Copper-Clad Steel Wire (mm)
Ground Rod (mm)
4.6
'A'
*
0.25
Length of Grounding Conductor
Total Required Length (m)
*
Maximum Length per Reel (m)
2,000
Tolerance in Length per Reel
±5%
Type of Reel
10TMSS05R01/MSO
wooden
Date of Approval: September 07, 2010
PAGE NO. 10 OF 11
TRANSMISSION MATERIALS STANDARD SPECIFICATION
6.0
10-TMSS-05, Rev. 01
DATA SCHEDULE
BARE COPPER-CLAD STEEL GROUNDING CONDUCTOR AND GROUND ROD
A.
ADDITIONAL TECHNICAL INFORMATION OR FEATURES TO BE FURNISHED BY
SEC:
B.
ADDITIONAL SUPPLEMENTARY DATA OR
BIDDER/VENDOR/SUPPLIER/CONTRACTOR:
B.
OTHER PARTICULARS TO BE FILLED UP BY BIDDER/VENDOR/SUPPLIER/
CONTRACTOR:
FEATURES
Actual Manufacturer
of Equipment/Material
PROPOSED
BY
Vendor/Supplier/
Contractor
Name of the Company
Location and address
Name and Signature of
authorized
representative
and date
Official Seal/Stamp
of the Company &
Date
10TMSS05R01/MSO
Date of Approval: September 07, 2010
PAGE NO. 11 OF 11