All-dielectric self-supporting optical cable (commonly known as ADSS optical cable) is a kind of non-metallic material optical cable which is all composed of dielectric materials, contains the necessary support system, and can be directly suspended on the power engineering tower. It is specifically used for overhead high-voltage transmission systems. It can also be used as a communication line in overhead laying environments such as lightning-prone areas and large spans.
ADSS optical cables are divided into two categories: layered structure and core tube structure.
Layer twist structure:
The layered structure is easy to obtain a reliable excess length of the optical fiber, although the diameter and total weight are slightly larger, which is more beneficial when used in medium and large spans.
The fiber optic loose tube is wound on the core lifting piece at the corresponding pitch, and then the inner sheath is extruded, and then wrapped with suitable spun yarn according to the required tensile strength, and then the PE or AT sheath is extruded. Because the cable core can be filled with ointment, but the resistance of the ointment is small, when the ADSS optical cable has a large span and has a large sag, the cable core is easy to "slip", and the loose tube pitch is easy to change. The loose tube can be fixed to the core riser and the dry cable core in a suitable way.
Core tubular structure:
The core tube structure is easy to obtain a small diameter, and the ice wind load is small; the total weight is relatively light, but the excess length of the optical fiber line is limited. The optical fiber line is placed in a PBT (or other suitable material) tube filled with water blocking ointment with the corresponding excess length, wrapped with suitable spinning yarn according to the required tensile strength, and then extruded into a PE sheath.
Advantages and disadvantages of adss cable:
It has a structure different from that of overhead wires, and has a strong ability to withstand extremely severe weather environments. And has the corresponding anti-pressure, can withstand the great grip of the tension clamp. However, when the smooth and stable lateral wind blows to the optical cable, wind vibration will occur, and fatigue damage will occur at the hanging point. Because the outer sheath is made of AT or PE material, there will be problems related to electrical corrosion when it operates in a strong electric field.