Virtual hands-on tutorial on OTDR testing

Long Link Testing.Long distance fiber optic links have unique testing needs. Two factors can limit bandwidth on long links, chromatic dispersion and polarization-mode dispersion. These topics are important but complicated, beyone this basic explanation, so there is a complete discussion on the topic and how testing is done in the FOA Online Reference Guide. More on CD and PMD.

The time may come when you have to troubleshoot and fix the cable plant. If you have a critical application or lots of network cable, you should be ready to do it yourself. Smaller networks can rely on a contractor. If you plan to do it yourself, you need to have equipment ready (extra cables, mechanical splices, quick termination connectors, etc., plus test equipment.) and someone who knows how to use it.

We cannot emphasize more strongly the need to have good documentation on the cable plant. If you don't know where the cables go, how long they are or what they tested for loss, you will be spinning you wheels from the get-go. And you need tools to diagnose problems and fix them, and spares including a fusion splicer or some mechanical splices and spare cables. In fact, when you install cable, save the leftovers for restoration!

And the first thing you must decide is if the problem is with the cables or the equipment using it. A simple power meter can test sources for output and receivers for input and a visual tracer will check for fiber continuity. If the problem is in the cable plant, the OTDR is the next tool needed to locate the fault. More from FOA Tech Topics: Troubleshooting and Restoration

December 22, 2011

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