Rj45 cat5e outlet wiring query

chrishall35 · Apr 23, 2023

htps://we.tl/t-JHXw09romZ quick share to photo
Hi there. I am trying to convert previous cable network cat5e installed when had non fibre in 2015 to digital. I have an outlet downstairs which used to be my master bt socket converted to t658a rj45 connected via an ethernet to the router. From that bt outlet only one cat5e cable visible which runs to TV outlet I also was able to convert to rj45 module t658a wiring. Upstairs become stuck as 2 cat5e cables present which had 2 colours wired together for PC connection. See photo of previous analogue wiring. Any suggestions on wiring? Do I need to wire colour from each cable into one module like u would with light circuit spur or can I have two modules modules one for each cable? I am diyer and should be OK otherwise as simple task.

Simon47 · Apr 23, 2023

I'm not completely clear what you are saying/asking, but I think it's this :
You have a piece of Cat5e cable which used to be a phone extension, and now you want to use it for ethernet. But at one end, you have two cables and don't know what to do here. It's not uncommon to use "network" cable for phone extensions - either because it's what someone had to hand, or (less likely in this case I think) because someone considered the option to change the use later on.

Assuming I have that correct, then the first thing is that no, you cannot put two cables into one RJ45. What you will need to do is separate those two cables and use the one that goes to the other socket. Try and keep the pairs properly twisted right up to the terminations as untwisting them (I've seen someone undo about 9" or more) upsets the transmission characteristics of the cable.
Also, make sure you keep the pairs correct - the sockets should be marked to show which terminal each colour goes to, but watch out for sockets marked to different standards.

As to the second cable, you have a couple of options.
One is to simply ignore it, tuck it into the back of the box out of the way. Don't cut it off, you may change your mind later and it's not easy to "cut some length back on" !
Alternatively, if you know where it goes to, then you could terminate that (use two separate sockets on one faceplate) to make another ethernet link - if you want a network connection there. You'd need a network switch to link the two ethernet connections and whatever equipment you have at the location in the photo.

Lastly, check carefully that the cable really does go from A to B in one piece. If there's another phone socket somewhere in the run wired in the same way as the photo, then your ethernet connection won't work.

chrishall35 · Apr 24, 2023

Simon47 said:
I'm not completely clear what you are saying/asking, but I think it's this :
You have a piece of Cat5e cable which used to be a phone extension, and now you want to use it for ethernet. But at one end, you have two cables and don't know what to do here. It's not uncommon to use "network" cable for phone extensions - either because it's what someone had to hand, or (less likely in this case I think) because someone considered the option to change the use later on.

Assuming I have that correct, then the first thing is that no, you cannot put two cables into one RJ45. What you will need to do is separate those two cables and use the one that goes to the other socket. Try and keep the pairs properly twisted right up to the terminations as untwisting them (I've seen someone undo about 9" or more) upsets the transmission characteristics of the cable.
Also, make sure you keep the pairs correct - the sockets should be marked to show which terminal each colour goes to, but watch out for sockets marked to different standards.

As to the second cable, you have a couple of options.
One is to simply ignore it, tuck it into the back of the box out of the way. Don't cut it off, you may change your mind later and it's not easy to "cut some length back on" !
Alternatively, if you know where it goes to, then you could terminate that (use two separate sockets on one faceplate) to make another ethernet link - if you want a network connection there. You'd need a network switch to link the two ethernet connections and whatever equipment you have at the location in the photo.

Lastly, check carefully that the cable really does go from A to B in one piece. If there's another phone socket somewhere in the run wired in the same way as the photo, then your ethernet connection won't work.

Thank u. That is exactly the info I needed and more. All ur assumptions correct. Greatly appreciated.