CAT5 and or serial continuity check HELP ME!!!

By winthrop.polk ·

Say I have a CAT 5 cable running from one place to another (say 100 meters). I cannot unplug the cable because it is carrying critical traffic. How can I physically determine where the cable goes.

Ideally, I'd like some sort of inductive non-invassive continuity probe that will not affect the traffic. Any suggestions?

Explaination: We have to travel to a site with about 100 PCs and Servers, PLCs, DCSs, HMIs, and other networkable components. We cannot unplug anything and do not want to add traffic to the network. How can we determine where all the untagged cables go?

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All Answers

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sounds like...

by Snuffy09 In reply to CAT5 and or serial contin ...

when i go fishing and get a "birds nest" in my reel.

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I agree...

by ThumbsUp2 In reply to sounds like...

Can't unplug it and can't invade it.... that's going to be a tough one to untangle, especially since CAT5 doesn't have trace wire on it like underground cable does.

Granted, they could probably go buy an expensive machine (has to be expensive if it's non-invasive) which could tell them there was something in the wall with electricity going through it. But, once they traced it back to a trunk where more than one line went through a hole in the wall, they're sunk trying to figure out which line they're following.

I think they need to unplug sumpin'!

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IntelliTone Toner and Probe

by jakepp In reply to CAT5 and or serial contin ...
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Thanks but.......

by winthrop.polk In reply to IntelliTone Toner and Pro ...

I have found similar tools. They all, including this one, require you to unplug one end of the cable and connect it to a tone generator. i.e. it works on active networks, but not active cables.

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Ethernet does not use all the pairs

by robo_dev In reply to Thanks but.......

it's an eight-wire cable, and 100-baseT only uses the middle four wires. So put the tone injector on the unused pairs where they are punched down.

If it's 568B pinout, the brown/brown-white and the blue/blue-white pairs are not used.

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I understand

by jakepp In reply to Thanks but.......

Sorry, I thought this had alligator clips that could work in active cables.

I'll post if I find something.

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he's asking a question without a real answer

by CG IT In reply to I understand

he can't unplug anything and he can put anything on the wire, so unless he physically follows the cable, there's really no to find out where a connection goes from the keystone panel to the wall outlet.

There are tools which will blink the switch light but that requires unplugging the host which he can't do. There are tools to send a packet on the wire to a destination, but he's said he can't do that either.

so, without a proper physical layout map in which to check what's actually out there, there's not much to do except crawl through the ceiling and follow cables.

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Perhaps, but......

by winthrop.polk In reply to he's asking a question wi ...

Well, I am an electronics engineer so I know it is possible to have a tool do the following:
1. Clamp a tone generator type device to one end of the cable sleeve. This should be purely inductive tone generator that does not require unplugging the cable and operates on a frequency that will not interfere with Ethernet traffic.
2. Take a tone detector, also inductive, and test the other end to make sure that is the same cable.

I know it's possible, but has anyone yet created such a device?

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