Description
Optical fibre composite overhead ground wire (OPGW) is an overhead ground wire containing optical fibre. It has multiple functions such as overhead ground wire and optical communication. It is mainly used for communication lines of 110KV, 220KV, 500KV, 750KV and new overhead high-voltage transmission system. It can also be used to replace the existing ground lines of the old overhead high voltage transmission system, add the optical communication line, transmit short time current and provide anti lightning protection. Other structures can be customized on request.
- Stainless steel tubes filled with hydrophobic gel provide the protection and support of the optical fibres
- Good tensile performance
- Small diameter, light weight, low additional load to the tower
- Appropriate fibre excess length of optical unit easliy to make
Applications:
OPGW cable is suited for installation on transmission lines with the double function of a ground wire (designed to replace traditional static or shield wires) and a communication wire. OPGW conducts short circuit current and provide lightning resistance as it “shields” conductors, while providing a telecommunications path for internal as well as third party communications. OPGW must be capable of withstanding the mechanical and environmental stresses inflicted on overhead cables (such those caused by wind or ice). OPGW must also be capable of handling electrical faults on the transmission line by providing a path to ground yet preventing damage to the delicate optical fibers inside the cable.
Construction
OPGW cable has two constructions:
Central loose tube type---The fibers are placed loosely in a sealed and water resistant central, aluminum tube filled with water blocking gel. This
tube provides protection to the fiber during installation and operation under severe environmental conditions. The stainless steel tube may also
be aluminum-clad steel depending on the engineering requirements. The stainless optical tube is located at the center of the cable protected by
single or multiple layers of aluminum clad steel, aluminum alloy wires, or steel wires. The metallic wires provide mechanical strength to withstand
severe installation and operating conditions, while achieving conductivity to control temperature rise during short circuit conditions.
Each optical fiber is clearly distinguishable utilizing a fiber identification system consisting of coloring and the number of ring marks on it. This
compact design features high mechanical strength and fault current rating within a smaller diameter. The smaller diameter also results in excellent
sag tension performance.
Multi loose tube type--- The fibers is placed loosely in a sealed and water resistant stainless steel tube filled with water blocking gel. Two or
three stainless steel optical tubes are helically stranded in the inner layer of a multiple-layer cable. The multi loose tube type is designed mostly for
very high fiber count requirement over 48 with the maximum fiber count reaching 144. The multi loose tube type can meet the requirement of huge
cross and large current capacity.
The optical fiber is made of high pure silica and germanium doped silica. UV curable acrylate material is applied over fiber cladding as optical fiber
primary protective coating. The detail data of optical fiber performance are shown in the following table.
Optical fiber uses special spun device successfully controlled the value of PMD, and makes sure that it can keep stable in cabling
Standards
IEC 60793-1 Optical fiber Part 1: Generic specification
IEC 60793-2 Optical fiber Part 2: Product specifications
ITU-T G.652 Characteristics of a single-mode optical fiber cable
ITU-T G.655 Characteristics of a non-zero dispersion-shifted single-mode optical fiber and Cable
EIA/TIA 598 Color code of fiber optic cables
IEC 60794-4-10 Aerial optical cables along electrical power lines – Family specification for OPGW
IEC 60794-1-2 Optical fiber cables-Part 1-2: Generic specification - Basic optical cable test procedures
IEEE1138-2009 IEEE Standard for testing and performance for optical ground wire (OPGW) for use on electric utility power lines
IEC 61232 Aluminum – clad steel wire for electrical purposes
IEC 60104 Aluminum magnesium-silicon alloy wire for overhead line conductors
IEC 61089 Round wire concentric lay overhead electrical stranded conductors
Optical Fibre Characteristics
Attenuation
(+20℃)
G.652
G.655
50/125μm
62.5/125μm
@850nm
≤3.0 dB/km
≤3.5 dB/km
@1300nm
≤1.0 dB/km
≤1.0 dB/km
@1310nm
≤0.35 dB/km
@1550nm
≤0.21 dB/km
≤0.22dB/km
Bandwidth (Class A)
@850nm
≥600 MHz·km
≥200 MHz·km
@1300nm
≥1200 MHz·km
≥600 MHz·km
Polarization Mode Dispersion
Individual Fibre
≤0.20ps/ km
≤0.20ps/ km
Design Link Value (M=20, Q=0.01%)
≤0.1ps/ km
≤0.1ps/ km
Technical Parameters
Diameter
(mm)
Rate Tensile Strength
(kN)
20℃DC
Resistance
(Ω/km)
Short Time Current Capacity
(40-200℃ kA2.s)
Note: Other optical fibre type and count, stranded wire are available om request.
No.
Technical Data
Product Type
Structure Type
Max. Fibre Count
1
OPGW-24B1.3-40-[51;9]
6/3.0/20AS, Optical Unit 1/3.0
24
≈40
9.0
≤304
≥51
≤2.10
≥9
2
OPGW-24B1.3-50-[58;11.5]
6/3.2/20AS, Optical Unit 1/3.2
24
≈50
9.6
≤345
≥58
≤1.82
≥11.5
3
OPGW-48B1.3-70-[77;24]
6/3.8/20AS, Optical Unit 1/3.8
48
≈70
11.4
≤475
≥77
≤1.30
≥24
4
OPGW-48B1.3-70-[42;38]
6/3.8/40AS, Optical Unit 1/3.8
48
≈70
11.4
≤340
≥42
≤0.70
≥38
Mechanical and Environmental Test Characteristics
IEC 60794-1-2-E1
Load: according to cable structure
Sample length: no less than 10m, linked length no less than100m
Duration time: 1min
40%RTS no additional fibre strain(0.01%), no additional attenuation (0.03dB).
60%RTS fibre strain≤0.25%,additional attenuation≤0.05dB
(No additional attenuation after test).
IEC 60794-1-2-E3
Load: according to above table, three points Duration time: 10min
IEC 60794-1-2-F5B
Time : 1 hour Sample length: 0.5m Water height: 1m
IEC 60794-1-2-F1
Sample length: No less than 500m Temperature range: -40℃ to +65℃
Cycles: 2
Temperature cycling test dwell time: 12h
Packaging and DrumStandard Cable Drum
Item
Test Method
Requirements
Tension
Crush
Additional attenuation at 1550nm ≤0.05dB/fibre; No damage to the elements
Water Penetration
No water leakage.
Temperature Cycling
The change in attenuation coefficient shall be less than 0.1dB/km at 1550nm.
Standard reel length: 2/3km/reel, other length is also available