Optical Cable Armor Selection

Choosing the right optical cable armor depends on installation environment, mechanical protection needs, rodent exposure, and compliance with standards. Key Considerations for Armor Selection1. Installation Environment: Direct Burial: Armored cables are recommended to withstand soil pressure, backfill impact, and potential future excavation.

Non-armored cables can be used in ducts where the conduit provides protection. Aerial Installations: Armored cables with steel wire armor (SWA) are preferred for tensile strength and anti-buckling, with periodic grounding every 200–500 meters.

Indoor/

Protected Conduits: Non-armored cables are lighter, more flexible, and easier to install in ducts or building interiors. 2. Mechanical Protection: Armored Cables: Include corrugated steel tape (STA), steel wire armor (SWA), or double-armored designs for high crush and impact resistance.

Single-armor provides 1000–3000 N/100mm crush resistance, while double-armor can reach 5000 N/100mm.

Non-

Armored Cables: Rely on jacket materials and non-metallic strength members (aramid yarn, FRP rods) for basic protection, suitable for low-risk environments. 3. Rodent and Pest Protection: Armored cables, especially steel tape or double-armored designs, offer superior resistance to rodent damage, which accounts for 15–25% of underground cable failures in North America.

Non-armored cables are vulnerable to bites and chewing and are not recommended in rodent-prone areas. 4. Cable Weight and Handling: Armored cables are heavier and more labor-intensive to install and splice, particularly double-armored or double-jacketed designs.

Non-armored cables are lighter, easier to handle, and more flexible, reducing installation time and effort. 5. Cost Considerations: Armored cables typically cost 30–50% more than non-armored cables but reduce repair frequency and long-term maintenance costs in harsh environments.

Non-armored cables offer upfront savings of 20–30% and are suitable where mechanical threats are minimal. 6. Standards and Compliance: Armored cables must comply with IEC 60794 mechanical tests for tensile, crush, and impact resistance.

Metallic armoring requires proper bonding and grounding to prevent electrical hazards from lightning or accidental contact with power lines.

Types of Armoring

Single Steel Tape Armor (STA): Corrugated tape providing radial compression resistance. Steel Wire Armor (SWA): Superior tensile and impact resistance, suitable for aerial or industrial environments. Double Armor: Combines tape and wire for extreme protection in mining, submarine, or high-rodent areas.

Dielectric Armor: Non-metallic fiber layers for specialty applications where electrical isolation is required.

Summary Recommendation

Use armored cables for direct burial, rodent-prone areas, industrial sites, or aerial installations requiring high tensile strength. Use non-armored cables in ducts, indoor environments, or protected conduits where mechanical threats are minimal. Select single vs. double armor based on the severity of mechanical threats, rodent activity, and budget constraints.

Ensure metallic armor is properly bonded and grounded to comply with safety standards and prevent electrical hazards. By evaluating the installation environment, mechanical risks, rodent exposure, and cost, you can select the optimal optical cable armor to ensure long-term reliability and performance.