Extending cat5e

[dom]

I've been putting cat5e cables throughout my place as part of the conversion project - all within the studwork.

Because of a late-in-the-day change in room layouts, the place where I'm drawing all the cables together has moved.

Being a sensible chap, I left plenty of spare length on the cables - except where I didn't.

So 4 cables need to be extended, and the joint location will become permanently closed within the cavity.

How to join these cables?

RJ45's and back-to-back connector?

Solder?

Something else?

[Andy Burns]

A couple of krone strips (the normal 237A ones are 10 pair, you have 16 pairs, so 2 cables per strip)

[Bob Eager]

These:

[Ian Jackson]

In principle, you can use anything which joins the ends of the wires together. This can be from the most obvious bodge to a sophisticated purpose-made connection device.

As it's a permanent connection, and using what I had immediately available, I would solder and heatshrink each joint in turn, then either heatshrink the lot, or wrap it tightly in self-amalgamating tape.

[Paul - xxx]

Solder and shrink wrap the wires, then either shrink wrap or self amalgamating tape over the whole lot before sealing up.

Then make a good note of where the joints are in the wall for future reference .. :)

[Tabby]

I'd solder them, and do my best to maintain the cable twists.

NT

[Tim Watts]

And keep the twists in each "pair" going as close as reasonably practical to the joints. Long (cm's) of untwisted wires in a pair seriously affects signal propogation[1] - more so at gigabit speeds.

[1]Less immune to external interferance, and less obviously, makes the joint look reflective to the signal (crude analogy - sun on your monitor makes it hard to read).

The pairs can be splayed out from one another though.

Cheers

Tim

[Bob Eager]

The jointing boxes I mentioned do work well, and just need a Krone tool to use them. I have two or three embedded in cavities around the house!

[geoff]

If you it that way, remember to stagger the joints

[Clueless]

Stupid question perhaps but is there no way you can use the "short" cables to pull full-length ones?

[Paul - xxx]

Can't give all the details away in one post ... spoils the fun of being able to say, in a month or two, "well, what you should have done AS WELL ... didn't you know that?"

[Howard Neil]

I'm waiting to see how the angle grinder will be suggested.;-)

[Tabby]

I think any joining method could be used. The plusses of soldering that led me to recommend it are:

- more robust than IDC

- more corrosion proof than IDC

- no need to buy anything or wait for it to arrive

- the twist of the cables can be maintained fairly much, maximising their speed and data integrity

The main downsides of soldering are:

- compared to other mthods, its slower to do the joint.

- soldering takes skill

NT

[Frank Erskine]

That seems a strange place to leave Krone tools... :-)

[Mike Tomlinson]

En el artículo , Ian Jackson escribió:

Not advisable IMO. The twists in the wire pairs in Cat5 cabling are what makes it resistant to external interference, and it's important to maintain the twist throughout the run, which separating, stripping, soldering and taping won't do.

I think using RJ45 plugs and back-to-back adapters is the best solution. It's faster, easier, neater, and maintains the twists in the pairs.

[John Rumm]

Yup, second that. I had to use a couple on my structured wiring system where socket positions needed to move from the designed location or where there was some unforeseen obstruction in the building fabric that took up more cable length to get past than anticipated.

Since you will already have the punch down tool for the patch panel etc, the mini krone strips in a box are an obvious solution.

[John Rumm]

Its partly a moot point since any modern network will be depending on IDC at every other point of connection - so one more set out of hundreds or thousands is neither here nor there... (the exception being if the connection needs to be in a "hostile" environment).

Always have a few joiners sat in my networking tool box ;-)

You don't need to untiwst particularly for a krone punch-down. (all my jointed cables seem to run gigabit speeds without any difficulty)

You will probably need to untwist more pairs to get the individual heatshrink on each wire. Nine lots of heatshrink in all is quite a faff.

[Ian Jackson]

In message , Mike Tomlinson writes

As the joint is inside the cavity, I would hesitate about not having soldered connections. If the plug/socket contacts ever become a bit dodgy, you're stuffed.

As for the twisting to maintain the balance of each pair of wires, I really doubt whether an inch or two where the twisting is not perfectly maintained is really going to make any significant difference.

As for being 'faster', the OP isn't joining CAT5 for a living. He has only four cables to do.

As for being 'easier', soldering, heatshrinking and taping isn't hard to do.

As for being 'neater', the joint is inside the cavity. No one will see it.

Otherwise, I agree completely with you.

[dennis]

8<

There is a reason why IDC is used so much.. its more reliable and has better corrosion resistance than soldered connections. Proper IDC connections are gas tight.

[John Rumm]

Assuming you have the crimp tool for the RJ45 plugs...

(even then I can punch down 16 wires into a krone block a darn sight quicker than I can fit two RJ45 plugs reliably!)