Surge protection for ADSL

Started by armadillo, Oct 14, 2010, 02:07:06

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g7pkf


All noted.

Yes inside every BT master socket there is some form of lightning protection it is either a neon bulb (used apx 20years ago) or a component that has a very very small gap the idea being the spark will jump the gap to earth. these type of surge protectors offer quite a good level of protection (suprisingly) and will work over and over-genrally.

3rd party devices have the added benefit of some indication if the surge protection has failed.

third party surge protectors genrally only work once, then either you replace the arestors (expensive equipment allows this), you throw it away and buy a new one or if it has a lifetime warrenty you return it.

I can assure you if you have either a direct strike to the BT line or your house nothing on this earth will protect your equipment.

A friend had a lightning strike hit his neighbour 6 doors away, it took out a bout half his roof, it took out every electrical appliance that was plugged in (even if it was switched off) for the whole row of terraced houses.

Someone i work with has his computer connected via surge and ups a tree in the field behind his house apx 50metres away got hit he lost 2 televisions, washing machine all his computer gear cordless phone and surprisingly his kettle (even his insurance questioned that).

I will get one of these to test as my line is apx 4Km long with an attenuation of 48-50dB and i get masses of interferance as the phone lines to the village run over a bridge apx 2metres away from the euston-MK main line.

£15 seems a resonable amount to spend and in a way i agree with you, if the whole lot frys now you have taken every precaution.

Oh and best you did use 3 core, just in case wife/girly plugs a nice fancy metal light in :)  additionally if you did use a 2 way trailing plug get a standard plug and plug it in the other point and then tape or tye wrap them solid. then wife/girly cannot plug hover in and blow fuse!

armadillo

From the Clarity site

http://www.clarity.it/xcart/product.php?productid=16152&cat=251&page=1

Quote
"But BT master sockets usually have a surge protector in them"
Yes they do. But it's only there to provide a basic protection for standard telephone equipment. Modems, and especially ADSL modems are a LOT more sensitive to sudden spikes than phones! Look at it this way; ask all the people with surge-fried modems in the last two decades whether the master's little surge arrestor was any use for sensitive comms equipment...

My BT master socket was installed at least 30 years ago, when there were no modems or routers and phones were bakelite things built like bricks.

Yes, I know nothing will protect against a direct (or even nearby) lightning strike. Your horror stories (funny about the kettle) go to emphasise an important lesson. The answer is definitely to disconnect and unplug everything if a thunderstorm occurs or is predicted when you around to do so or if you are going away during the thunderstorm season. The surge protector is more for the smaller surges or things that happen when you are out. At least then, you have done everything you reasonably could for £15, as we agree. The rest is down to fate or the gods or whatever you live by.

I did use a single trailing socket, not a double, and it is clearly labelled. Never had a wife and the delicious days of girly are, I suspect, alas behind me. Such visitors as I do have are not in the habit of plugging random appliances into my sockets so I should be safe enough with 2 core!

A main railway line is an unfortunate source of interference  :(

g7pkf



I used to work in the security industry and have just found what must be one of the best line surge arrestor's avalible at the time.

don't have camera to hand but when i do my faceplate review i will add it, It even has an earth lead connection :)

Any protection is better than none.

And your never too old to get a girly.

armadillo

Quote from: armadillo on Oct 19, 2010, 12:28:05

The router is still connected to the surge protector via a plain RJ11 to RJ11 flat cable about 2m long. I have ordered a 0.5m Pro+ Cat5 shielded connector from AdslNation (thanks Ted!). When it arrives, I shall see if replacing the flat cable makes any difference and report my findings.

I said I would report findings on the effect of replacing the 2m flat cable with the 0.5m shielded Cat5e. I have now had several days to evaluate the results. I checked noise margin, sync and throughput immediately before powering down and replacing the cable. I also compared variability in noise margin between when the old cable was in place and the new one. I repeated the swapover several times.

I can confidently report that there is no difference between the two cables, either in the noise margin or the variability of the noise margin. I am continuing to use the new one anyway because it is white and shorter and neater. But, in terms of performance, it has made no difference.

I am sure that, over a long cable route, say 10m or more, it would make a difference. But over the short one, and given the particular position of my router, it does not. I think it is safe to conclude that such noise as is on my line does not originate from within the vicinity of my router or its cabling. And the variations do not correlate with electrical activity, such as heating pumps, fridges, freezers etc in my house.

For anyone joining this thread anew, without having read the whole thing (forgiven!), I do not have a problem with noise.

Ted

#104
Quote from: armadillo on Oct 26, 2010, 21:49:39
I am sure that, over a long cable route, say 10m or more, it would make a difference. But over the short one, and given the particular position of my router, it does not. I think it is safe to conclude that such noise as is on my line does not originate from within the vicinity of my router or its cabling. And the variations do not correlate with electrical activity, such as heating pumps, fridges, freezers etc in my house.

I'd agree with that, and at least you know that your set up is as good as you can get it, nice and tidy too.  :thumb:

Just finished changing my own set up. Router now by the NT5e with 4x cat6 cables (2x20m 2x15m) running to the rooms upstairs. Was quite a bit of work, but I'm happier with it now.
Anybody fancy an Adslnation 10m RJ11 Pro+ ?
Ted
There's no place like 127.0.0.1

armadillo

Quote from: Ted on Oct 26, 2010, 22:52:50
I'd agree with that, and at least you know that your set up is as good as you can get it, nice and tidy too.  :thumb:

Thanks Ted. Yes. I once had a boss who used to say: "And if my best is not good enough, sack me!"

Your setup must have involved some little holes in the ceiling too. I felt like a vandal drilling holes in the corners of mine. There is an element of satisfaction in putting in the work and knowing you have done the best you could do.

Thank you for all your help. I have learned more about cables and filters than I ever dreamed existed. And that is no doubt a very insignificant proportion of what I still have to learn.

Polchraine

Quote from: armadillo on Oct 26, 2010, 21:49:39
I said I would report findings on the effect of replacing the 2m flat cable with the 0.5m shielded Cat5e. I have now had several days to evaluate the results. I checked noise margin, sync and throughput immediately before powering down and replacing the cable. I also compared variability in noise margin between when the old cable was in place and the new one. I repeated the swapover several times.

I can confidently report that there is no difference between the two cables, either in the noise margin or the variability of the noise margin. I am continuing to use the new one anyway because it is white and shorter and neater. But, in terms of performance, it has made no difference.

I am sure that, over a long cable route, say 10m or more, it would make a difference. But over the short one, and given the particular position of my router, it does not. I think it is safe to conclude that such noise as is on my line does not originate from within the vicinity of my router or its cabling. And the variations do not correlate with electrical activity, such as heating pumps, fridges, freezers etc in my house.

For anyone joining this thread anew, without having read the whole thing (forgiven!), I do not have a problem with noise.

Thanks for the update.    At least you now know you do have a nice neat set up and your equipment is protected.   There will be cases where twisting and shielding does work - my installation for example, where, if I was to install a 2m flat cable I would be well hammered!

I'm desperately trying to figure out why kamikaze pilots wore helmets.

armadillo

I do try to give an update after promising it. I hate it when threads are abandoned in mid air by the OP.

Thank you Polchraine for all your help.


Polchraine

Quote from: armadillo on Oct 27, 2010, 13:25:26
I do try to give an update after promising it. I hate it when threads are abandoned in mid air by the OP.

Thank you Polchraine for all your help.



No problem ...  next task is to identify me on another forum that you also visit!

I'm desperately trying to figure out why kamikaze pilots wore helmets.

Rik

Rik
--------------------

This post reflects my own views, opinions and experience, not those of IDNet.

Polchraine

Quote from: Rik on Oct 27, 2010, 18:16:52
:lol:

Go on, give him a clue. ;)

That would make it too easy!    I have found him already so should not be too hard!
I'm desperately trying to figure out why kamikaze pilots wore helmets.

Rik

Rik
--------------------

This post reflects my own views, opinions and experience, not those of IDNet.

armadillo

#112
Quote from: Polchraine on Oct 27, 2010, 18:14:47
No problem ...  next task is to identify me on another forum that you also visit!

Loves heights  :thumb:

Polchraine

I'm desperately trying to figure out why kamikaze pilots wore helmets.

armadillo