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We had a contractor wire up our office with all the cables leading back to a central location. The only problem is that he didn't label anything, so we have no idea which cables go to which room. One end of the cable is terminated in a wall-jack (in the rooms), the other end is un-terminated and will be punched to a patch panel. Is there a way to identify the cables without having to terminate them? We'd like to group the cables on the patch panel by room, but I don't want to crimp/punch each cable twice. Thanks!

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Can you get a cable toner? – jscott Nov 4 '13 at 20:13
I'd rather not have to buy anything, but I do have a multi-meter. Could we do something with a battery and a multi-meter or something? – Jon Tackabury Nov 4 '13 at 20:32
up vote 8 down vote accepted

Get a tone generator ( and plug that into the terminated end and use the probe to find the cables on the other end.

And anytime a cable is pulled make sure the installer plans to label them cables in a manageable way (I've done site visits before even accepting a bid for work to make sure the installer does quality work)

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Agreed. The scope of work should include labeling of both ends of the cable being installed. It should also include certifying the cabling. – joeqwerty Nov 4 '13 at 20:26
I agree, and I missed this when arranging the installation. Let's just say that they did the minimum amount of work possible. – Jon Tackabury Nov 4 '13 at 20:33
A tone generator is definitely the way to go. I'll have to grab one at Home Depot or something to finish this job correctly, thanks guys. – Jon Tackabury Nov 4 '13 at 20:41

Instead of punching down the entire cable, just punch down one wire (of the 8 in the CAT6 cable), e.g. the orange one, then cut open a patch cable, plug it into one plug and then electrically test that connection (using testing leads, a 9V battery and a little lightbulb/buzzer.

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Hmmm. I think using a tone/probe would be a lot simpler and less intrusive. – joeqwerty Nov 4 '13 at 20:30

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