Shocking ISP Supplied Pre-Made Patch Lead Discovery

[CCTVCam]

Just a warning for anyone who uses the pre-made patch cable supplied by their ISP.

Today I broke the cable tester out to test a small patch cable I made up to go router to modem as the pre-made ones were too long - I only wanted anout 12 inches as they sit side by side. Whilst there I decided to test my entire network, all of which tested fine. However, when selecting a patch cable to shorten, I decided to use and test the ISP supplied cables (which I always save unused in a bag for a rainy day) - supplied from multiple ISP's over the years.

For RJ45 Patch cables, I found a failure rate of around a staggering 50% taken over about 10 cables tested.

It can't get any worse can it?

Hell Yes. I tested RJ11 patch cables next. I found a failure rate of around 75% of the cable tested over about 8 cables tested.

In 10 mins my bin went from empty to looking like the rejects bin at a cable manufacturer.

The moral of the story here seems to be always test your patch cables. Don't assume those shiny new sealed in the packet cables from your ISP are fault free cables, they might not be and on my results that chance could be quite high.

Incidentally, all the bought accesssory patch cables in my system I tested passed perfectly suggesting the issue lies with bulk produced ISP cables rather than accessory ones, although after today, I'd always test all cables bought or otherwise.

 

[fenderman]

Just a warning for anyone who uses the pre-made patch cable supplied by their ISP.

Today I broke the cable tester out to test a small patch cable I made up to go router to modem as the pre-made ones were too long - I only wanted anout 12 inches as they sit side by side. Whilst there I decided to test my entire network, all of which tested fine. However, when selecting a patch cable to shorten, I decided to use and test the ISP supplied cables (which I always save unused in a bag for a rainy day) - supplied from multiple ISP's over the years.

For RJ45 Patch cables, I found a failure rate of around a staggering 50% taken over about 10 cables tested.

It can't get any worse can it?

Hell Yes. I tested RJ11 patch cables next. I found a failure rate of around 75% of the cable tested over about 8 cables tested.

In 10 mins my bin went from empty to looking like the rejects bin at a cable manufacturer.

The moral of the story here seems to be always test your patch cables. Don't assume those shiny new sealed in the packet cables from your ISP are fault free cables, they might not be and on my results that chance could be quite high.

Incidentally, all the bought accesssory patch cables in my system I tested passed perfectly suggesting the issue lies with bulk produced ISP cables rather than accessory ones, although after today, I'd always test all cables bought or otherwise.

It is possible that in a money saving effort when gigabit was a pipe dream, they were only using cables with two pairs in them or perhaps they were not connecting 4/5 and 7/8. It would be interesting to cut them open and check. Are they all failing at 4/5 and 7/8? Same with the rj11 likely only two wires for a basic single line.

 

[TechieTech]

If you have one of the Klein testers that measures the cable length, you can use it to see which end the failure is on if you can't figure it out visually.

 

[CCTVCam]

It is possible that in a money saving effort when gigabit was a pipe dream, they were only using cables with two pairs in them or perhaps they were not connecting 4/5 and 7/8. It would be interesting to cut them open and check. Are they all failing at 4/5 and 7/8? Same with the rj11 likely only two wires for a basic single line.

Bizarrely enough with the RJ45's 3 cables (presumably all the same from the same manufacturer and batch) had exactly that - only 2 conductors out of 8 showing connected - 3 & 4, and they were crossed ie 3-4 and 4-3. Have to wonder if someone set up a machine wrongly as these were supplied as pc to router patches and so shouldn't be crossed. The others had multiple connectors not showing a connection.

If you have one of the Klein testers that measures the cable length, you can use it to see which end the failure is on if you can't figure it out visually.

I've just got a cheap tester. It does the job though. Because it has a remote end and both ends have indicator lights, it's easy to figure out which plugs have which faults because each plug has it's own set of indicator lights.

 

[IAmATeaf]

Are you sure they are proper utp cables? I’ve got a box full that came with various bits of kit and I’ve never had a diff one but I do have various cables that look like utp but are intended for other uses. For example a couple are for modems and another for use as a serial console cable for routers/switches.

 

[SpacemanSpiff]

Bizarrely enough with the RJ45's 3 cables (presumably all the same from the same manufacturer and batch) had exactly that - only 2 conductors out of 8 showing connected - 3 & 4, and they were crossed ie 3-4 and 4-3.

Bizarre indeed... only a single pair (2 conductors) testing out as crossed is spot on for a telephone cable, until you mention the RJ-45 connector. If an RJ-45 was deliberately used, it would think it would still start from the center two (pins 4 & 5).

Regardless, much to what @fenderman mentioned a basic Ethernet cable requires 2 pair (4 conductors) RX +/- (pins 1&2) & TX +/- (pins 3&6) to function.

Bad cable? Or pretty good odds that the cables are proprietary for the equipment they came with.

 

[CCTVCam]

Are you sure they are proper utp cables? I’ve got a box full that came with various bits of kit and I’ve never had a diff one but I do have various cables that look like utp but are intended for other uses. For example a couple are for modems and another for use as a serial console cable for routers/switches.

Yeah they were supplied with the ISP's integrated router/modems/switches, the RJ45's as patches for PC to router and the Rj11 as patches from router to telephone. All the cables had all the connectors and wires present just some were dead and others not.

Maybe there was something going on with proprietory connectiions. Who knows. Either way, useless to me and binned now.

I made this one up from a patch cable that had all 8 connectors functioning - factory plug at one end, my plug at the other. Boots were both mine. It tests and functions fine:

It's the Red one. The Modem / Router are in a temporary arrnagement atm. However, you can see why I wanted a short cable as eventually they will beside by side not much more than this apart:




..and yep the surface will be dusted when all the work stops!

Cable labels are my work also. I like it neat.

 

[NightLife]

That poor cable sequestered to the rear, against the wall looks like it was dragged through wet grass, and mud. It needs a little love