Standard tolerance shall be +/- 2. 0 inches; however, the tolerance should be as loose as possible or specified as “located approximately. ” Cable assembly pig-tails (fan-out) labels will be referenced from the tip of connectors. As data rates increase to 400 Gig and beyond, and new fiber applications emerge, it's easy to be confused about which fiber testing parameters are enough to guarantee support for high-speed applications. The OTDR is also commonly used to create a "picture" of fiber optic cable when it is newly installed. Environmental requirements such as temperature, humidity, vibration, shock, etc., should be communicated to the cable assembly. When manufacturing cable assemblies I often see drawings with no specific length tolerance, and – as we all know – with anything made by hand, even with the assistance of automated tooling, the finished length can vary. 125 feet > 5 to 50 +5% / -0 20 feet 20 feet 21 feet > 50 to 100 +4% / -0 75 feet 75 feet 78. Fiber optic cables are designed to transmit light signals over long distances, but some signal loss is inevitable due to various factors such as attenuation, dispersion, and bending losses.
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