Self-supporting aerial optical cable laying

Self-supporting aerial optical cables, such as ADSS and figure-8 types, are designed to span between poles without additional support, allowing safe and efficient fiber optic deployment.

Types of Self-Supporting Aerial Cables

• ADSS (All-Dielectric Self-Supporting): Non-metallic, lightweight, and capable of spanning up to 1000 meters between poles. Ideal for installation near power lines due to electrical isolation. Fibers are loosely distributed to prevent attenuation from cable deformation .
• Figure-8 Cable: Combines a steel messenger and optical fiber in a single figure-eight jacket. Provides high tensile strength and can span up to 180 meters. Variants include GYTC8S, GYXTC8Y, and GYXTC8S, offering water resistance, UV protection, and mechanical durability .

Installation Considerations

• Route Survey: Conduct a thorough survey to identify utilities, streets, and obstacles. Ensure sufficient clearance from power lines and other cables according to the National Electrical Safety Code .
• Poles: Use dead-end poles to anchor the cable and intermediate poles to support spans. ADSS cables require careful attention to tension and sag, while figure-8 cables integrate the messenger for simpler installation .
• Hardware: Include spacers, straps, and suspension hardware to prevent chafing and maintain cable alignment. For lashed systems, proper spacing and tensioning of the messenger strand are critical .

Safety Precautions

• Personnel must follow OSHA regulations, NESC standards, and local safety rules. Use leather gloves for climbing, rubber gloves near electrical circuits, and safety harnesses on aerial lifts .
• Inspect poles for deterioration, splinters, or hazards before climbing. Avoid installation during severe weather such as high winds, rainstorms, or lightning .
• Maintain minimum safe distances from energized lines and use insulated tools when working near live conductors .

Installation Techniques

• Controlled Paying-Off: Ensure stable tension when unrolling the cable from drums to prevent fiber damage .
• Bending Radius: Respect the minimum bending radius to avoid microbending or breakage of optical fibers .
• Sealing: Protect cable ends with waterproof tape to prevent moisture ingress, which can increase attenuation or cause fiber breakage .
• Tensioning: For figure-8 cables, tension the messenger component between dead-end poles. ADSS cables require careful tensioning to account for thermal expansion and creep .

Best Practices

• Utilize existing utility poles to reduce costs and construction time.
• Position optical cables in the uppermost communication space on poles.
• Regularly inspect and maintain hardware and tools to ensure safe and reliable installation . By following these guidelines, self-supporting aerial optical cables can be installed efficiently, safely, and with long-term reliability, whether using ADSS or figure-8 designs.