Finding the break in a network cable?

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Panting like a fiend
I'm trying to sort out one of the network connections in our house, according to my basic tester there are 2 or 3 broken wires in the cable.

Now the obvious answer is to replace the cable, but it's going to be a pain to do that, so depending on where the break is I may be able to move the connector, but it's only worth doing if the break is within a certain area.

What I'm wondering is, is there a cheapish tool that can let me find the breaks without cutting off 6 inches of cable at a time? ;) (the tool would almost certainly get used again in the future so I don't mind buying it if it's not too expensive).

I suspect the breaks are probably at the same point at roughly one of two locations, as the cable was working find about 9 months ago, but we've been doing some minor redecoration and I suspect that the cable has been pinched badly at one point.
 
I would try and suggest something but I've only used £2-10 testers and Fluke £10,000 testers with nothing in between :p
 
I've not got one in any of the machines down here, but the Prosafe Switch I'm connecting it to reports no device connected on it.

According to the cheap tester (basically a continuity one that can walk through the pins)

1 is dim
2 - lights up 1 dimly at the far end
3 nothing
4-8 work normally.

I've tried redoing the socket at the far end, so my guess is that it is just a damaged cable but I can't trace it visually.
 
The cheap SC8108 tester will measure the length of each cable pair. It does seem reasonably accurate, and you can calibrate it against a known length of cable.

Whether it'd be accurate enough for this job I don't know. But testing from both ends should give you a reasonable idea.
 
Cheers, I think I'll try ordering that tomorrow (unless anyone has any other suggestions).

I'm going to bite the bullet and run another cable (I was planning on doing that at some point) but if it can save me having to run two at this point that's good.
 
I think some Broadcom NICs might have a feature where you can do a cable length test as well.

Worth a try. You'll probably need the 'fatter' drivers rather than whatever comes from Windows Update.
 
The suggestions about the broadcaom and intel drivers made me look in my prosafe switches settings again.

It has the test and reckons it's a short at 6-7 meters (it varies when i test it repeatedly).
But it also means I can now dig out a tape measure and see if I can spot the damage.

Cheers for the replies so far guys :)
You're stars :)

[edit]
I've ordered one of the SC8108 testers as it occurred to me that I'm increasingly adding to our network and it's going to be helpful especially with some of the cabling where it goes to a "dumb" device rather than a PC or the prosafe switch.
 
I know, I know! ;)

Unfortunately at the time I ran the cable (nearly 15 years ago) it seemed like I'd allowed plenty, and I don't think anyone suggested doubling up ;) (there were also cost and space constraints).

This time I'm running two, fortunately an old cable for the boiler controls is no longer in use so I'm able to pull that through clearing more room for the new cables.
 
Now the obvious answer is to replace the cable, but it's going to be a pain to do that

Although you've suggested otherwise would it not be easier to run new cables using insulation tape to wrap around the connectors and pull the new cable through?

Have done this many a time and with a person either end trying not to rip the granny out of it taking a bit of care and time works a treat.
 
Aye that's basically what I've done, I'm also going to take out an unused cable which will let me pull a second one :)

I'd remembered how hard it was when I did it before, but forgotten that since then I bought a cable access kit.

It's amazing how much easier it is when you're able to use an existing cable, and have the proper tools.

At some point I think I may have to move the main switch to a new more central location as it would be a lot easier to run cables.
 
I think I found the problem...


yeahthatlldoit.jpg
 
I don't think it as chewed, it was inside a non cavity wall, I think what has happened is that the initial damage was possibly done because it was between a hotwater pipe and sharp brickwork so over time it's rubbed, then when I pulled it it got worse.

This is if it's the actual original break and not one that I've done whilst pulling that section of cable free, I've still got to pull out the last few feet where it passes through the ceiling but that one was at about the right distance.
 
I must admit, that also happened with my ex..;) :p

I rather cheekily reused the good parts of the old cable to make a couple of patch cables for the switch to the wall point (they're not going to get touched so single core should be fine) and they work, so it looks like it was that one break.

The new tester arrived as well, and that is quite an advance on the old one, not least because It displays the result of the test on the main unit, including any wiring discrepancies (IE swapped 1-2), which is handy as I was really too tired to do one of the wires last night and accidental swapped two of the conductors round when making up the plug (some minor cursing was heard then I redid it).

I've taken this chance to sort out some of the cabling between the main switch and the wall sockets so there is less excess, and so that it's easier to track cabling (where I made up the new cables they've been booted to correspond to the markings on the fixed cables).

If I redo all the patch cables to the wall sockets I can have a rainbow :)


[edit]
Does anyone else find watching the indicators on a network switch is almost hypnotic? The prosafe port indicators are oddly relaxing to watch.
 
I rather cheekily reused the good parts of the old cable to make a couple of patch cables for the switch to the wall point (they're not going to get touched so single core should be fine) and they work, so it looks like it was that one break.

I was going to suggest that, as useless as it may be, that it would give some confirmation that the photo'd damage was the entire issue.

Does anyone else find watching the indicators on a network switch is almost hypnotic? The prosafe port indicators are oddly relaxing to watch.

All you need now is some relaxing music and it'd be like a relaxation spa!
 
Oh, I pulled a fresh pair ,)
I just used the good parts of the old one to make a couple of patch cables to go from the sockets to the switch.
 
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