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That socket is wired wrongly. Swap your white/grn and org and it will be sorted. These sockets are confusing - be sure the follow the 'B' column on both sides.
If you're wrong, but consistently wrong, both ends will of course test OK electrically, but the four balanced twisted pairs will be mixed up, affecting the signal.
Also, as others have said, leave the pairs twisted until the last possible point! (And note the frequency of twist in each pair is different. No one said network cabling, for maximum performance, was easy :))
Thanks mark that's a great explanation, I hadn't thought of that technical side so thankyou
 
Not sure Strima, sorry. Customers leads. He is quite a bit cleverer computer wise than me so didn't really question it.
It's not a common issue but it has been known to happen.
 
That socket is wired wrongly. Swap your white/grn and org and it will be sorted. These sockets are confusing - be sure the follow the 'B' column on both sides.
If you're wrong, but consistently wrong, both ends will of course test OK electrically, but the four balanced twisted pairs will be mixed up, affecting the signal.
Also, as others have said, leave the pairs twisted until the last possible point! (And note the frequency of twist in each pair is different. No one said network cabling, for maximum performance, was easy :))
What does this do Mark? How does leaving them twisted together help?
This has been an interesting thread!
 
What does this do Mark? How does leaving them twisted together help?
This has been an interesting thread!

I’m no expert on this, but do like to understand things, and know it’s to do with using a ‘balanced signal’ for low-noise transmission.

On each pair, there is a +ve-going and -ve-going signal, with only the difference them being detected at the far end. If there’s external noise induced on the line, it will usually appear on both wires equally, so remains undetected, as any noise waveform simply provides a signal on both wires equally, not affecting the difference signal. Result: a magically clean signal in a noisy environment!

The twisting reduces cross-talk between pairs in a multi-pair cable. Consider if, due to the extreme proximity of all those little wires, one of a pair might receive a larger crosstalk signal that its partner, it will be unbalanced, affecting the difference signal and so be resolved at the other end as noise, messing up fast data comms.

But if the pairs are twisted, the crosstalk hits one strand first for a bit, then the other for a bit, and so on. Therefore the crosstalk signal is magically applied to each pair’s partner equally. It then ‘looks’ like external noise at the other end and is unresolved.

Twist frequency differs so that different pairs don’t keep crossing at the same points again and again, reducing the cancellation effect.

Clever ennit? :)

I think I've got that essentially right, but if there are any comms network designers on here who know better, please take over!

(cf. Balanced professional microphone cabling using 3-pin XLR connectors and shielded two-core interconnects).
 
I’m no expert on this, but do like to understand things, and know it’s to do with using a ‘balanced signal’ for low-noise transmission.

On each pair, there is a +ve-going and -ve-going signal, with only the difference them being detected at the far end. If there’s external noise induced on the line, it will usually appear on both wires equally, so remains undetected, as any noise waveform simply provides a signal on both wires equally, not affecting the difference signal. Result: a magically clean signal in a noisy environment!

The twisting reduces cross-talk between pairs in a multi-pair cable. Consider if, due to the extreme proximity of all those little wires, one of a pair might receive a larger crosstalk signal that its partner, it will be unbalanced, affecting the difference signal and so be resolved at the other end as noise, messing up fast data comms.

But if the pairs are twisted, the crosstalk hits one strand first for a bit, then the other for a bit, and so on. Therefore the crosstalk signal is magically applied to each pair’s partner equally. It then ‘looks’ like external noise at the other end and is unresolved.

Twist frequency differs so that different pairs don’t keep crossing at the same points again and again, reducing the cancellation effect.

Clever ennit? :)

I think I've got that essentially right, but if there are any comms network designers on here who know better, please take over!

(cf. Balanced professional microphone cabling using 3-pin XLR connectors and shielded two-core interconnects).

As being a bit of a data and as it happens live sound guru myself I can only agree with you. What you are saying is dead correct.
 
haven't done ethernet sockets before but hundreds of bt sockets which I hadn't had any problems with.
To my mind if the colours match at both ends which they do and I have tested to check they shouldn't stop anything working. But do you think the fact they are untwisted would affect the quality of connection ?

And I only meant neater in a sense that they weren't tight without any slack :)

BT sockets are completely different and a bit of untwisting doesn't usually affect them.
The colours need to be in the correct places so that each twisted pair has the correct data signal on it. Mixing the signals between different pairs will likely turn the data into nonsense.

The twisted pairs are used to cancel out interference, being twisted together ensures that both cores receive the same interference so that it can be cancelled out at the receiving end. The number of twists per metre is tightly controlled in the manufacture of the cable for this reason.
 
haven't done ethernet sockets before but hundreds of bt sockets which I hadn't had any problems with.
To my mind if the colours match at both ends which they do and I have tested to check they shouldn't stop anything working. But do you think the fact they are untwisted would affect the quality of connection ?

And I only meant neater in a sense that they weren't tight without any slack :)

BT sockets are completely different and a bit of untwisting doesn't usually affect them.
The colours need to be in the correct places so that each twisted pair has the correct data signal on it. Mixing the signals between different pairs will likely turn the data into nonsense.

The twisted pairs are used to cancel out interference, being twisted together ensures that both cores receive the same interference so that it can be cancelled out at the receiving end. The number of twists per metre is tightly controlled in the manufacture of the cable for this reason.
 
This is an excellent example why sparks should not do a network engineers job. (or aerials for that matter).

No it isn't, there are many electricians who have the knowledge and experience to do this correctly.
This is another example of why someone shouldn't just have a go at doing something without seeking the knowledge or training to do it correctly.
 
The cable jacket should stop as close to the module as possible.

The jacket should be cable tied to the strain relief loop, hence the tiny little cable tie usually included with the modules.

Ethernet point no internet Untitled - EletriciansForums.net
 
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No it isn't, there are many electricians who have the knowledge and experience to do this correctly.
This is another example of why someone shouldn't just have a go at doing something without seeking the knowledge or training to do it correctly.
I think the first statement was a bit strong but I'll take the 2nd one!

Basically a good customer said to me can you put me a point in for my internet so I don't have to use wireless. I was already taking the floor up and fishing cables for other jobs so I said it's not something I normally do but yes ok.

Anyway thanks to you all for your input it's now working I re-terminated, shorter and swapped the orange and white over to where it should be. Customer very happy and I didn't charge them for the sorting out. I am happy to stand here and be judged but overall I'd say thanks for your all your help, I do realise it's free advice from people but I've spent two unpaid hours on it and do try and help people on here where I can and where other people haven't already beaten me to it. The main thing is 1. I know something I didn't before and 2. Customer's got what they asked for and is happy.

Thanks again all
 

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