Author: Site Editor Publish Time: 02-09-2024 Origin: Site
All-Dielectric Self-Supporting (ADSS) cables are a type of optical fiber cable uniquely capable of selfsupporting installation between structures, eliminating the need for conductive metal elements. Commonly utilized by electrical utilities, these cables are installed alongside existing overhead transmission lines, often using the same supports as electrical conductors.
ADSS cables offer a cost-effective alternative to OPGW (Optical Ground Wire) and OPAC (Optical Phase Conductor) cables. They are engineered for strength, enabling installations spanning up to 700 meters between support towers. Their design focuses on being lightweight and having a small diameter to minimize the impact on tower structures from factors like cable weight, wind, and ice.
The cable's design ensures the internal glass optical fibers are supported with minimal strain, maintaining low optical loss over the cable's lifetime. A protective jacket shields the fibers from moisture and safeguards the cable's polymer strength components from solar UV radiation.
Preformed tension dead-end grip is usually used in the installation of the exposed conductor, electric transmission & distribution, and overheard insulated conductor. The reliability and economic advantage are better than the present bolt type and hydraulic
compression type Tension clamp Dead-end which now is being widely in the line. ADSS cable guy grips were developed to grip the ADSS fiber optical cable during the construction of internet network lines on wood poles or concrete towers.
ADSS suspension clamp is also called preformed suspension clamp or AGS suspension clamp, it offers a complete set of Aluminum clad, rubber, armor grip, bolt, and nut to support and protect the ADSS/OPGW cable from damage due to bending.
These clamps support the weight of the cable across spans. They're designed to minimize stress and bending at the support points.
FTTH ADSS Anchor Tension Clamp:
Applied at points where the cable is under tension, like at sharp directional changes or ends, to maintain cable integrity and prevent damage.Brackets are used to attach the cable's support hardware to poles or towers. They provide a stable base for other fittings.
Hooks are used to guide and support the cable along its installation path, particularly on poles or towers.
Stainless Steel strapping is ideal for ADSS cable and pipe banding applications that require various bundle diameters.
- Metal channel structural frame provides a durable light-weight design with ridged strength that is easy to install.
- Corrosion Resistant Materials - Aluminum.
- Bolt together Crossarm packs in the uniform low-profile container that reduces shipping costs and is easier to inventory.
- Multiple Keyholes adapt various Splice Cases.
- Wide cable keepers avoid point loads and provide better cable support.
Down-lead Clamp is designed to lead down cables on the splice and Terminal Poles/ towers and to fix the arch section on the Middle Reinforcing Poles/ towers.
Normally, a unit of Down-lead Clamp is needed per 1.5 meters, and it is also used in other fixing areas.
The cables are designed to be strong enough to allow lengths of up to 700 meters to be installed between support towers. ADSS cable is designed to be lightweight and small in diameter to reduce the load on tower structures due to cable weight, wind, and ice. In the design of the cable, the internal glass optical fibers are supported with no strain to maintain low optical loss throughout the life of the cable. The cable is jacketed to prevent moisture from degrading the fibers. The jacket also protects the polymer strength elements from the effect of solar ultraviolet light. Using single-mode fibers and light wavelengths of either 1310 or 1550 nanometres, circuits up to 100 km long are possible without repeaters. A single cable can carry as many as 144 fibers.
ADSS cables made by ZION COMMUNICATION with 6,12,24,48,96 fibers range from 200 to 250 kg/kilometer and are between 11 and 17 mm outside jacket diameter. These cables can support between 4 TO 50 kilonewtons of tension.s determined.
In order to properly design the structure of the ADSS cable, many aspects must be considered, including mechanical strength, conductor sag, wind speed b ice thickness c temperature d topography, Span, and Voltage.
Usually, when you are in production, you need to consider the following questions.
Jacket Type: AT/PE
PE sheath: ordinary polyethylene sheath. For power lines below 110KV and ≤12KV electric field strength. The cable should be suspended where the electric field strength is small.
AT sheath: anti-tracking sheath. For power lines above 110KV, ≤20KV electric field strength. The cable should be suspended where the electric field strength is small.
Out Cable Dia.:Single Jacket 8mm-12mm; Double jacket 12.5mm-18mm
Fiber Count:4-144Fibers
Aramid Yarn Details: Something like (20*K49 3000D). This main calculation of tensile strength.
According to the stress formula, S=Nmax/E*ε,
E (Tensile modulus)=112.4 GPa(K49 1140Dinner)
ε=0.8%
Usually designed strain<1%(Stranded Tube)UTS;
≤0.8%, evaluation
Nmax=W*(L2/8f+f);
L=span(m);usually 100m,150m,200m,300m,500m,600m;
f=Cable sag; usually 12m or 16m.
Nmax=W*(L2/8f+f)=0.7*(500*500/8*12+12)=1.83KN
S=Nmax/E*ε=1.83/114*0.008=2 mm²
Saramid(K49 2840D)=3160*10-4/1.45=0.2179mm²
N numbers aramid yarn=S/s=2/0.2179=9.2
General aramid fiber hinge pitch is 550mm-650mm,angle=10-12°
W=Maximum load (kg/m)=W1+W2+W3=0.2+0+0.5=0.7kg/m
W1=0.15kg/m(This is the weight of ADSS cable)
W2=ρ*[(D+2d)⊃2;-D⊃2;]*0.7854/1000(kg/m) (This is the weight of ICE)
ρ=0.9g/cm³, the density of ice.
D=Diameter of ADSS. Usually 8mm-18mm
d=Ice cover thickness;No ice=0mm,Light ice=5mm,10mm;Heavy ice=15mm,20mm,30mm;
Let's say the ice is thick is 0mm, W2=0
W3=Wx=α*Wp*D*L=α*(V⊃2;/1600)*(D+2d)*L/9.8 (kg/m)
Let's say the wind speed is 25m/s, α=0.85; D=15mm;W3=0.5kg/m
Wp=V⊃2;/1600 (Standard partial pressure formula, V means wind speed)
α= 1.0(v<20m/s);0.85(20-29m/s);0.75(30-34m/s);0.7(>35m/s) ;
α means Coefficient of the unevenness of wind pressure.
Level | phenomenon | m/s
1 Smoke can indicate the wind direction. 0.3 to 1.5
2 The human face feels windy, and the leaves move slightly. 1.6 to 3.3
3 The leaves and micro-techniques are shaking, and the flag is unfolding. 3.4~5.4
4 The floor dust and paper can be blown up, and the tree's twigs are shaken. 5.5 to 7.9
5 The small leafy tree sways and wavelets in the inland waters. 8.0 to 10.7
6 The big branches are shaking, the wires are vocal, and it is not easy to lift the umbrella. 10.8~13.8
7 The whole tree is shaken, and it is inconvenient to walk in the wind. 13.9~17. l
8 The micro-branch is broken, and people feel very resistant to moving forward. 17.2~20.7
9 The grass house was damaged, and the branches were broken. 20.8 to 24.4
10 Trees can be blown down, and general buildings are destroyed. 24.5 to 28.4
11 Rare on land, large trees can be blown down, and general buildings are severely damaged. 28.5~32.6
12 There are few on the land, and its destructive power is enormous. 32.7~36.9
RTS: Rated tensile strength
Refers to the calculated value of the strength of the bearing section (mainly counting the spinning fiber).
UTS: Ultimate Tensile Strength UES>60% RTS
In the effective life of the cable, it is possible to exceed the design load when the cable by the maximum tension. That means the cable can be overloaded for a short time.
MAT: Max allowable working tension 40% RTS
MAT is an essential basis for sag-tension-span calculation and necessary evidence to characterize the stress-strain characteristics of ADSS optical cable. Refers to the design of meteorological conditions under the theoretical analysis of the total load and cable tension.
Under this tension, the fiber strain should be no more than 0.05% (laminated) and no more than 0.1% (central pipe) without additional attenuation.
EDS: Every Day Strength (16~25)% RTS
The annual average stress, sometimes called the moderate daily stress, refers to the wind and no ice, and the yearly average temperature, the theoretical calculation of the load cable tension, can be considered the ADSS in the long-term operation of the intermediate pressure (should) force.
EDS is generally (16~25) %RTS.
Under this tension, the fiber should have no strain, no additional attenuation, that is, very stable.
EDS is also the fatigue aging parameter of optical fiber optic cable, according to which the anti-vibration design of optical fiber optic cable is determined.