split pairs

gallantman

Hi,

I have to add two network points to the Shop Floor and had two Cat5e cables ran from each location to the COMS room.

I punched down one cable to the patch panel in the same sequence as all the other cables - WhiteBlue, Blue, WhiteOrange, Orange, WhiteGreen, Green, WhiteBrown and Brown (see patch panel.jpeg). Added a jack to the other end going by the colour sequence on the jack (see jack.jpeg) - checked with the cable tester and all worked ok.

Repeated for the second cable and when I tested got a "split pairs" error on the cable tester. Re-wired both ends, tried a different jack, and tried a different point on the patch panel but still the same error.

So got the guys to run a new cable, re-wired it but still getting the same error.

I don't understand - using the exact same wiring sequence on both ends and still getting the error.

Cable has been replaced so eliminated as a problem. Also using same patch cable on both ends of the tester when testing so that’s not the problem. Both cables are on the same patch panel.

Any ideas?

-pm

taldar

Normal
1. Orange/white
2. orange
3. green/white
4. blue
5. blue/white
6. green
7. brown/white
8. brown

use that on both ends you should have no problems

FusionNet

Make sure as well when wiring to follow the British standard on both sides. As you may know there are two standards, 568A and 568B as well as others. But the difference is that they reverse the pairs 3-6 and 1-2 on the american ones. So even though your punched in the right colours just make sure your in the right one as in 568B on both ends..

gallantman

Thanks for the replies - what I don't understand is that I have two cables - one is wired and working perfectly. The second is wired identically - beside the first on the patch panel and giving this error.

Both are identical !!

pm

FusionNet

you could be experiencing cross talk. Are both cables run side by side the whole way? Is it a good brand of cable?

Can you also let us know if you are using the same modules throughout the system?

This is a site with info that may help:

http://www.google.ie/imgres?imgurl=http://www.aeatechnology.com/uploads/AN225-A.jpg&imgrefurl=http://www.aeatechnology.com/software/application-notes/an225&usg=__R4I1dmG6UVcmJNQBMmdMiAK_d84=&h=240&w=284&sz=29&hl=en&start=4&um=1&itbs=1&tbnid=NLaRKqpKpYyrWM:&tbnh=96&tbnw=114&prev=/images%3Fq%3Dsplit%2Bpairs%26um%3D1%26hl%3Den%26sa%3DX%26tbs%3Disch:1

gallantman

firstly my terminology may be wrong - I am wiring a patch panel on one end and a socket on the other - jack may have been the wrong wording.

They run side by side for some of the way but not it all as they are loacted on two different sides of the building. I havn't seen the route my self but need to check.

The wiring is good quality - could electrical wires cause issues ?

gm

msg11

gallantman wrote: »

The wiring is good quality - could electrical wires cause issues ?

gm

Yes.

As for the problem.

>Make sure all the wires are securly pinned down on the patch panel.
>Make sure all the wires are correctly pinned out to A/B standert whichever your using
>Make sure the wires are making contact with gold pins within the jack itself.
>Also, test the cable your using into the patch panel, and also make sure it's the right cable for whichever standert your using A/B

From my grasp on things, the problems always seen to lie in them jacks that are made up on site, there very fiddly to get into the right order and get a good connection.

gallantman

Fair enough but both ends have been re-wired a few times by both the electrician and myself.

Found a spare lan cable in an un-used socket nearby and traced to back to the Coms room. Had to wire the socket but it was already punched down on the patch pane and I got a signal.

I think the problem is the route the cable take - i.e. some electrical interference.

pm

FusionNet

I agree or it could be one other thing. The modules you are using are a prettu nasty brand and they do have a high fail rate, you may have a few that are just not 100%.

gallantman

OK - but the module or socket I used in the end I took from the LAN cable I was failing to get a signal on !!

gm

FusionNet

Im confused!! You used a module from a failing connection? Also cheap modules can only be punched down ONCE. My panduit ones are ten times and Krone are twice. After this they say they can not be sure it will work as the pins get damaged.

Id use a different brand of module if I were you....

layke

Just a thought man, what's the distance that cable is running?
I'm just ruling out attenuation.

gallantman

Hi FusionNet

I used the module becasue I was interested to see if it would fail - if it did fail then I would use a new module.

It didn't fail - I now have a network connection on the third LAN cable.

So I have ran two LAN cables to this area and the most recent module I was using works OK on a third LAN cable.

So if its not the module, and not the cables then either the route the cables take (maybe ?) or the patch panel - but as I mentioned I wired another lan cable into the same patch panel !!

gm