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internal UTP cabling

internal UTP cabling

internal UTP cabling


could need some help with internal cabling.

The wall outlet (a-end) is cabled like

1 = orange
2 = orange-white
3 = green
4 = blue-white
5 = blue
6 = green-white
7 = brown
8 = brown-white

the b-end of the internal cable needs to go directly in an ethernet socket which is MDI-X.

so I have set the b-end exactly as the wall outlet pinout, there is some network exchange but if fails DHCP acknowledment.

Then i have changed the b-end pinout to normal straight through cable:
1 = orange-white
2 = orange
3 = green-white
4 = blue
5 = blue-white
6 = green
7 = brown-white
8 = brown

but same result, which did surprised me, there was some network activity but no kept disconnecting.

I suspect the internal cable might be too long for proper operation?

Or do I need to change the cabling pin out?

Dont understand what i am doing wrong?

Any ideas?


RE: internal UTP cabling


Looking at the photo, you have a termination problem. The wires should be in the bottom of the terminals, not looped over the top. The blue and blue white look to be ok but the rest won't be making good contact. Contact is made by the edges of the connector cutting through the insulation to make contact with the inner conductor.


RE: internal UTP cabling

Pairs are all reversed too.

Pin Color
1 White/orange
2 orange
3 white/green
4 Blue
5 White/blue
6 green
7 white/brown
8 brown

The pin numbers are in the jack you can clearly see in the pic the 8 is not brown etc...

RE: internal UTP cabling

Tnx, much appreciated cody, i didnt notice that, makes sense now, the former residents only used 1 pair (blue and blue/white) hence the rest isnt done correctly.

Gonna fix it, with the right pin outs as well.

thnx again :)

RE: internal UTP cabling

As well as what cody and tt said, make sure to keep the individual pair twist as close to the termination as possible.

Always look out for the next guy because it may be you!

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