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Special Considerations When Installing Fiber Optic Cables

Leaps and bounds faster than copper-based alternatives, many industry experts consider fiber optic cable to be the future of internet connectivity, and the benefits of deploying fiber optic cabling in modern networks in most cases outway the drawbacks of doing so. Faster, lighter, and allowing signal integrity across longer distances than CAT 5e and CAT 6a, the go-to alternatives when copper-based cables are used, fiber optic cables do require installers to take a number of factors into account during the process. Let’s look at some of these challenges in detail.

Take Care Around the Bend

Fiber optic cables are composed of thin strands of glass surrounded by a flexible insulated coating. The glass strands themselves are fragile, and depending on the gauge and manufacturer, the minimum bend radius comes into play during installation. The minimum bend radius represents the point beyond which a cable should not be wound or bent beyond, as doing so will result in damaged and broken strands of glass and compromise the integrity of the data signal. If no minimum bend radius is designated by the manufacturer, the general practice is to go with a value of no less than 15 times the cable diameter, or around 2 inches.

Pull Into Place With Care

Another consequence of being made up of glass strands is that fiber optic cables are given a maximum tensile rating, or a maximum amount of force they can withstand before breaking. Installation techniques are designed to minimize how much force is placed on fiber optic cables as they are pulled into place from reels and pull boxes.

Go Vertical At Your Own Risk

Cables have a maximum vertical rise, or maximum distance it can be installed vertically without including support, due to the weight of the cable and tensile strength ratings of the glass strands within a fiber optic cable. In order to minimize the impact of gravity, fiber optic cable installations should remain as horizontal as possible. When it is necessary, transitioning from horizontal to vertical, and then back to horizontal also requires taking into account the minimum bend radius and should include methods to secure the cable at the top of the rise in order to reduce the downward pressure on the interior of the fiber optic cable.

Protect Existing Installations Against Impact of Future Installation

Once a cable has been installed into a duct, future installations can result in cables becoming entwined and movement of already installed cables can cause bends, kinks, or twists. Any combination of the above can impact the integrity of installed fiber optic cables and disrupt service. During installation, if a future expansion of fiber optic cable is anticipated, it’s suggested that multiple extra fibers be pulled through the duct and connected in the future as needed in order to minimize the impact of tensile load damage or future damage due to the installation of new cabling along ducts where cabling is already in place.

Duct Installation Should Take into Account Preconnectorized Assemblies

In some cases, it’s more efficient to install fiber optic cable that has been fit with connectors in place already, rather than installing connectors after the cable has been pulled through the duct. Preconnectorized cables require special equipment and ducts of a sufficient size to allow clearance. Careful planning of the segments of the network that might require such cable to be used ensures that you’ve taken into account the different minimum bend radius and tensile ratings of preconnectorized cables and prevents delays in the installation process.

Leave Some Slack for Future Network Modifications

Due to the fragility and other challenges posed during the installation of fiber optic cables, it’s important to plan for future expansion, repairs, or changes to the network. Leaving 20-30 feet of slack in the installation allows for damaged sections to be easily fixed or segments to be expanded to meet up with new sections of network or terminals and cable plants without splicing.

We Know Our Way Around Fiber Optics

If your network expansion or build includes a need for high speed cabling options, it’s important to consult with SANDirect’s group of experts to share your needs so we can help you ensure your decisions take into account the unique challenges of installing fiber optic cables.

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