Requirements for auxiliary materials for overhead line optical cables

Auxiliary materials for overhead optical cables include grounding wires, clamps, dampers, pole fittings, and earthing components, all designed to ensure mechanical stability, electrical safety, and compliance with international standards.

Grounding and Lightning Protection

Overhead optical cables must be properly grounded to protect against lightning and electrical faults. Terminal poles, lead-in poles, and key poles near substations require direct buried lightning protection grounding wires, while discharge terminals, corner poles, crossing poles, branch poles, and poles above 12 meters require pull-wire lightning protection grounding wires. Suspension wires should also be grounded, and grounding points are typically installed at intervals of every 200 meters along parallel high-voltage lines and at least once per kilometer for all overhead lines.

Inside the machine room, the optical cable reinforcement core must be connected to the ODF frame lightning protection ground, which is then linked to the outdoor ground wire using a 16 mm² power cable.

Hardware and Fittings

Auxiliary materials include a variety of hardware fittings designed for mechanical support and electrical safety: Clamps: Cradle clamps, palm clamps, line taps, and pistol grip strain clamps secure the cable to poles and support structures. Dampers: Vibration and spacer dampers reduce mechanical stress and prevent fatigue on the cable. Repair Sleeves: Used for splicing or repairing damaged sections of the cable.

Stay Assemblies: Provide additional support and stability to poles or structures. Drop-out Fuses (DOF): Protect high-voltage equipment by breaking the circuit during overloads or short circuits. All fittings are designed according to IEC, ANSI, and NFC standards to withstand mechanical and electrical loads at various voltage levels.

Earthing Materials

Proper earthing is critical for safety and system reliability. Required materials include: Earth rods and connectorsCopper plate earthingEarth rod clamps and copper-clad steel connectorsEarth tail clamps for connecting auxiliary wires to the grounding system Poles and Structural SupportsWooden poles, either treated or untreated, are selected based on species and specifications suitable for electricity distribution, transmission, and telecom networks. Poles must meet mechanical strength requirements and be compatible with the auxiliary fittings and grounding systems.

Standards Compliance

Auxiliary materials and installation practices must comply with fiber optic construction standards and recommendations such as ITU-T G. 652 for single-mode fibers and ITU-T G. 957 for optical systems.

These standards ensure proper mechanical, optical, and electrical performance of the overhead optical cable system.

Summary

In summary, auxiliary materials for overhead line optical cables include: Grounding wires and lightning protection componentsClamps, dampers, and repair sleevesStay assemblies and pole fittingsEarthing rods, connectors, and copper platesDrop-out fuses for electrical protectionPoles and structural supports meeting mechanical and environmental requirements All materials must conform to international standards to ensure safety, reliability, and long-term performance of the overhead optical cable network.