Maintaining Existing Cabling Cabling

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3.1.2 Maintaining Existing Cabling

For existing cabling, you wont have as much latitude as with a new installation. You certainly wont want to go back and replace working cable just because it does not follow some set of standards. But there are several things you can do to make your life simpler when you eventually encounter problems. The first step in cable management is knowing which cable is which and where each cable goes. Perhaps the most important tool for the management and troubleshooting of cabling is a good label maker. Even if you werent around when the cable was originally installed, you should be able, over time, to piece together this information. You will also want to collect basic information about each cable such as cable types and lengths. You will want to know which of your cables dont meet standards. If you have one of the more sophisticated cable testers, you can self-certify your cabling plant. You probably wont want to do either of these tasks all at once, but you may be able to do a little at a time. And you will definitely want to do it for any changes or additions you make. Labeling Cables This should be a self-explanatory topic. Unfortunately for some, this is not the case. I have very vivid memories of working with a wiring technician with years of experience. The individual had worked for major organizations and should have been quite familiar with labeling practices. We were installing a student laboratory. The laboratory has a switch mounted in a box on the wall. Cabling went from the box into the wall and then through cable raceways down the length of the room. Along the raceway, it branched into raceways built into computer tables going to the individual computers. The problem should be clear. Once the cable disappears into the wall and raceways, it is impossible to match the end at the switch with the corresponding end that emerges at the computer. While going over what needed to be done, I mentioned, needlessly I thought, that the cable should be clearly labeled. This was just one part of my usual lengthy litany. He thought for a moment and then said, I guess I can do that. Then a puzzled expression came over his face and he added in dead earnest, Which end do you want labeled? Id like to think he was just putting me on, but I dont think so. You should use some method of attaching labels that is reasonably permanent. It can be very discouraging to find several labels lying on the floor beneath your equipment rack. Also, you should use a meaningful scheme for identifying your cables. TIAEIA-606 Administration Standard for Telecommunications Infrastructure of Commercial Buildings provides one possibility. See Appendix B for more information of TIAEIA standards. And, at the risk of stating the obvious, unless you can see the entire cable at the same time, it should be labeled at both ends.

3.1.3 Testing Cabling