Most fiber optic cables boast a pull strength of 200+ pounds thanks to the internal kevlar or aramid yarn, known as the strength member. The most common damage is a broken fiber, which is difficult to detect. But fibers can also be cracked from too much tension during cable pulling or despooling. Jerald Rounds, Arizona State University. Incorrect methods can lead to reduced light passing through the fibers (high attenuation), cable stretching and cosmetic irregularities in the cable, or in the worst case broken or “dark” fibers when tested. just to name a few. Every reel you pull and every conduit you go through has tension. You'll hit a tight bend, a rough spot, or a little drag in the duct and that's all it takes for the load to spike. Excessive Length of Fiber Optic Cable: Long fiber optic cables can lead to performance issues.
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