What is ADSS Fiber Optical Cable?
The all-dielectric self-supporting optical cable is a non-metallic optical cable that is composed of all dielectric materials and contains the necessary supporting system. It can be directly suspended on power poles and towers.The ADSS fiber optical cable is mainly used for communication routes of overhead high-voltage power transmission systems, and can also be used for lightning Communication lines in high-prone areas, large-spans, and other overhead laying environments.
Because the ADSS optical cable dances in the same path as the high-voltage power line, its surface is not only required to be as resistant to ultraviolet radiation as the ordinary optical cable, but also required to withstand the test of the high-voltage and strong electric environment for a long time. The capacitive coupling between the optical cable and the high-voltage phase line and the earth will produce different spatial potentials on the surface of the optical cable. Under the influence of meteorological environment such as rain, snow, frost, and dust, the potential difference causes leakage current locally on the surface of the damp and dirty optical cable. The resulting thermal effect causes the moisture in some areas of the surface of the optical cable to evaporate. At the moment of evaporation, the leakage current is interrupted to produce an arc and Larger heat energy, the accumulated heat energy will burn the surface of the optical cable, forming a tree-like trace, which is the so-called electric trace. Over time, the outer sheath is damaged due to aging. From the surface to the inside, the mechanical properties of the aramid yarn are degraded, and the optical cable will eventually break. To solve this problem mainly from two aspects. One is to use a special tracking resistant sheath material to extrude the outer sheath of the aramid yarn, that is, to use AT tracking resistant sheath to reduce the tracking corrosion of the surface of the optical cable by strong electricity; in addition, the power poles are installed on the power poles through professional software. Calculate the spatial potential distribution and draw the electric field intensity distribution map. According to this scientific basis, determine the specific suspension point of the optical cable on the tower, so as to avoid the optical cable from being subjected to a stronger electric field.
1.ADSS optical cable has a different structure from overhead conductors. Its tensile strength is borne by aramid rope. The elastic modulus of aramid rope is more than half that of steel, and its thermal expansion coefficient is a fraction of that of steel, which determines the arc of ADSS optical cable. Vertical is more sensitive to external load changes. The elongation of the ADSS optical cable can reach 0.6% in the icing state, while the wire is only 0.1%; the sag is relatively slow to temperature changes, and the sag remains basically unchanged when the temperature changes; the wind deflection angle is very high under strong wind conditions. When the wind speed is 30m/s, the wind deflection angle can reach 80°, and the wind deflection angle of the wire is only about half of that of the optical cable.
2.Strong ability to withstand extreme weather (high winds, icing, etc.).
3.The outer sheath of ADSS optical cable is made of AT or PE material, which runs in a strong electric field, and there is a problem of electric corrosion.
4.ADSS fiber optic cables are subject to wind vibration. Smooth and stable horizontal wind blows to the optical cable, wind vibration will occur, and fatigue damage will occur at the hanging point.
5.The ADSS optical cable has a certain degree of resistance to pressure and can withstand the greater grip strength of the tensile clamp.
ADSS optical cables work in a large-span two-point support (usually hundreds of meters, or even more than 1 km) in an overhead state, which is completely different from the traditional concept of “overhead” (the post and telecommunications standard overhead suspension wire hooking program, 0.4 meters on average for optical cables 1 pivot). Therefore, the main parameters of ADSS optical cables are in line with the regulations of power overhead lines.
MAT maximum allowable tension
Refers to the tension on the optical cable when the total load is calculated theoretically under the design weather conditions. Under this tension, the fiber strain should be ≤0.05% (stranded) and ≤0.1% (central tube) without additional attenuation. In layman’s terms, the excess length of the optical fiber has just been “eaten” at this control value. According to this parameter, meteorological conditions and the controlled sag, the allowable span of the optical cable can be calculated under this condition. Therefore, MAT is an important basis for the calculation of sag-tension-span, and it is also an important evidence for characterizing the stress-strain characteristics of ADSS optical cables.
RTS rated tensile strength
Also known as ultimate tensile strength or breaking strength, it refers to the calculated value of the sum of the strength of the load-bearing section (mainly counted as spinning fiber). The actual breaking force should be greater than or equal to 95% of the calculated value (the breaking of any element in the optical cable is judged as cable breaking). This parameter is not optional, and many control values are related to it (such as tower strength, tensile hardware, anti-vibration measures, etc.). For fiber optic cable professionals, if the ratio of RTS/MAT (equivalent to the safety factor K of overhead lines) is not appropriate, that is, a lot of spun fibers are used and the available fiber strain range is very narrow, the economic/technical performance ratio is very poor. Generally, MAT is approximately equivalent to 40% RTS.
It mean stress Sometimes called daily average stress, it refers to the theoretically calculated tension of the optical cable under load under no wind, no ice and annual average temperature. It can be considered as the average tensile (strain) force of the ADSS during long-term operation. EDS is generally (16~25)%RTS. Under this tension, the optical fiber should have no strain and no additional attenuation, that is, very stable. EDS is the fatigue aging parameter of the optical cable at the same time, according to this parameter determines the anti-vibration design of the optical cable.
UES limit running tension
Also known as special use tension, it refers to the maximum tension of the optical cable that may exceed the design load during the effective life of the optical cable. It means that the optical cable allows short-term overload, and the optical fiber can withstand strain within a limited allowable range. Generally, the UES should be >60% RTS. Under this tension, if the strain of the optical fiber is <0.5% (central tube) and <0.35% (stranded), additional attenuation will occur to the optical fiber, but after the tension is released, the optical fiber should return to normal. This parameter guarantees the reliable operation of the ADSS optical cable during its lifetime.
ADSS Fiber Optical Cable Accessories
Small Preformed Guy Grip& Tension Set for ADSS
Medium Preformed Guy Grip High Tension & Tension Set for ADSS
Tangent Clamp for ADSS,Monolayer Preformed Suspension Set for ADSS
Suspension Set for ADSS
Double Suspension Set for ADSS
Tension Set for OPGW
Double Tension Set of OPGW
Preformed Suspension Clamp for ADSS Cable
Anchoring Clamp for ADSS Cable
Suspension Clamp for ADSS Cable
Post time: Sep-13-2021