All-dielectric self-supporting (ADSS) fiber cables provide advantages over strand and lash fiber networks for electric utility applications in many cases. Some of these advantages to ADSS cables include:
• No metallic components – can install in supply space and grounding is not required
•Little to no “make ready” cost
• Lower hardware costs • Speed and ease of installation
• Minimal long term maintenance
• Longer expected design life
In most scenarios, these advantages lead to a lower total cost for the electric utility and telecommunication company. Whether the utility is using the fiber system for internal supervisory control and data acquisition (SCADA) or a revenue generating fiber-to-the-x (FTTx) solution, there are a number of considerations when deciding between these two fiber cable methods. Each application and system is unique, but in many cases an ADSS cable is advantageous to a strand and lash cable for both cost and convenience.
INSTALLATION AND LONG TERM MAINTENANCE
Speed of installation can be significantly improved for ADSS cables when compared to strand and lash loose tube cables. ADSS cables are installed in a single pass, while strand and lash loose tube cables must be installed in two passes. Cable installation steps for each method are shown below.
• Pole “make ready” (pulley placement)
• Cable Installation
• Cable Sagging
• Hardware Attachment
Strand and Lash Cable
• Pole “make ready” (pole change out, guying, moving cables, etc.)
• Messenger Placement
• Messenger Pre-tensioning (creep)
• Messenger Hardware Attachment
• Cable Placement
• Lashing Wire Placement and Termination
• Bonding and Grounding
When a company is considering adding aerial fiber optic cables to their system, it is important to understand the total cost of ownership. There are certainly scenarios where the total cost of ownership of a strand and lash loose tube cable is lower than an ADSS cable, such as over-lashing a cable to an existing and available messenger wire. However, in many situations, the total cost of ownership can see savings for an ADSS system in the 17-20% range with just the direct cost elements. This savings even considers a higher cable and total installation cost for qualified personnel. Other impacts including not needing to ground, training ease, longer service life, and higher reliability of an ADSS cable makes it the preferred solution to a strand and lash loose tube cable network.