Running ADSL extension cable outside - surge protection?

I am getting a new ADSL adaptor faceplate for the NTE5 Master Socket.

The existing telephone extensions can be wired to the filtered output thus isolating the older wiring.

Now I need to run a new unfiltered ADSL extension from the faceplate to where the modem is located, in the opposite corner of the house. I propose to run suitable external grade Cat5e cable along the outside walls and use a suitable telephone or RJ45/RJ11 wall socket. It would be a nightmare to run the extension indoors through the rooms now nicely decorated.

I have searched for a simple answer regarding surge/lightning protection, without success. Opinions vary from complete "no-no" to run telephone extension (or ethernet) outdoors, to regarding it as fairly irrelevant.

Obviously, the Master Socket (MS) already has a surge protector. I understand that a direct lightning strike will fry equipment regardless of the MS surge protector anyway, and that "proper" protection is very expensive and disruptive and not done in domestic scenarios. Only BT can afford to do this but it pays off as they don't have to unplug all their equipment during a storm. For us mortals, any surge protection is really limited to static caused by distant lightning strikes or storms in general, and provided by some spark or gas discharge device between a pair of wires without any path to earth. It's a goodwill measure really, based on the fact that replacement equipment is not too expensive.

I am guessing:

(a) As the new extension is hardwired to the Master, it is already protected by the Master's internal surge device anyway.

(b) If a modern ADSL modem is connected to the new remote extension, it already has its own internal surge protector.

(c) Modem cable inline protectors are available - but in view of (b), and (a), this is probably redundant.

(d) The extra line could be terminated similarly to the Master by using an extension wall socket with just a surge protector in it (maybe by clipping out the other bits from an old style Master). This is a bit radical and for flexibility, (c) would be better.

Whilst I understand the concern to both equipment and personal safety that is expressed regarding lightning, I cannot see that being remedied without expensive installation mentioned above. I am inclined to just wire up to a standard extension box.

I was wondering if anyone has any opinions on this?

In reply to a post by alexadsl:

I was wondering if anyone has any opinions on this?

They will vary, but mine is that I don't use surge protection equipment at all, other than on a socket spitter for my AV stuff in the lounge. In several locations I have never had call to replace equipment due to surges.

Unless there's some reason to believe your property is more prone to lightning activity than the average, I wouldn't bother.

If you are concerned you could run FTP (as in foiled twisted-pair).
It doesn't need to be a more full on type of STP where each of the 4 pairs has its own shield.

In this respect it would be roughly similar to how with coaxial cable induced currents tend to stay on the outer conductor.

You could ground the foil (it should have a drain wire when you strip it) because if running outside you can literally drive a metal rod into the ground and make a good connection to it, but perhaps grounding to an existing water pipe is easier.

As I understand it, would be safer if the foil part doesn't protrude into the sockets at either end to avoid unintended contact.

However, unless your outdoor cable was running to some kind of antenna or something else more likely to to be hit, or is likely to pick up noise along the run, it's probably not necessary to shield it.

Common advise is not to follow electrical (power) cables, but other than that it is the way the pairs are twisted inside ethernet (and good telephone) cables that helps to reduce interference.

Edited by prlzx (Thu 08-Mar-12 01:22:43)

Use external grade Cat5e and preferably SWA ... then run it at very low level.

However, I would put the modem/router where the master is and then use teh cable to deliver 100Mbps Ethernet and 'phone, or Gbit Ethernet to the new location. You can easily put a small 8 port switch at that location to provide additional connections.