On 12/25/2010 08:44 AM, S Mathias wrote: > Two questions that was not always clear for me [sorry for posting to this list :\]: > > ############################################################################################## > > Q1) when cabling, is the color order important? like: > > straight cabling: > A side: white-orange, orange, white-green, blue, white-blue, green, white-brown, brown > B side: white-orange, orange, white-green, blue, white-blue, green, white-brown, brown > > could be eg.: like this?? > A side: white-orange, brown, white-blue, green, white-green, blue, white-brown, orange > B side: white-orange, brown, white-blue, green, white-green, blue, white-brown, orange > If you look at the cable, you will see that the wires are twisted in pairs. White-orange with orange, white-blue with blue, etc. For noise cancellation, it is important that you use pairs for each data path. On a short cable, you can get away with out doing this, but it is not a good idea. Each pair also has a different twist ratio - twists/inch. This helps prevent them from interfering with each other. If you put a good cable tester on the cable, it will tell you if you do not have pairs matched up. Some can also tell you if you have the pairs switched. They can also tell you the length of the run, and all kinds of information about the quality of that you can expect from the run of cable. This gets important when you get into longer runs. Part of the color pattern is a legacy from 2 pair telephone cables. the center pair was blue and while-blue and the pair outside of that was white-green and green. (reversed of the center pair.) Though not a good practice, it is possible to have a phone signal on the blue/blue-white pair while also using it as a data cable. I leave the signal quality of this combination to your imagination. One last note - when you get into cables with more then 5 pair, the background color changes from white. If my foggy brain is working correctly, then next set uses red. (Oh yes - the 5th pair is white-violet, violet.) You also get a red stripe on the colors like the colored stripe you observed on the white wires. So you would get a red with an orange tracer paired with a orange with a red tracer. One additional tidbit - there are an A and B configuration. We are using the B configuration. Mikkel -- Do not meddle in the affairs of dragons, for thou art crunchy and taste good with Ketchup!
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