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Standard User ajdroberts
(newbie) Fri 06-Nov-15 00:58:38
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Lightning Protection Pot (LPP) removal - safe?


[link to this post]
 
I have written elsewhere about my various disconnection problems and slow speeds.

Faulty (high resistance) connections, which were cleaned up, and a Lightning Protection Pot (LPP) that was disconnected from my line, eliminated the disconnections and raised my speed from 0.5mbps to (all of) 2.8mbps. (It is a direct to exchange copper line of 3km)

So, apart from the 7 weeks it took for the ISP to identify and BTO engineers to repair the problems they found - problems which I was consistently being told were my own cabling, modem/router, micro-filter etc, - am I safe?

500m of my overhead line was largely buried 10 years ago after a dangerous lightning strike (my phone exploded) but around 100m of overhead still exists in open country. I was told that LPPs are no longer used as they have proved to be unreliable, as I have found, so presumably some newer form of protection is provided?

If so, how would I know that I have that alternative protection as nothing was done at the time of the disconnection of the LPP?

Might I have been left out to fry?

Edited by ajdroberts (Fri 06-Nov-15 09:03:27)

Administrator MrSaffron
(staff) Fri 06-Nov-15 09:32:46
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Re: Lightning Protection Pot (LPP) removal - safe?


[re: ajdroberts] [link to this post]
 
Master socket contains a small lightning protector, but lightning is such that a direct strike will usually bridge any small gap, remember how big a gap it has already jumped from a cloud.

People lose xDSL hardware to lightning each year as the sensitive RF components are easily fried.

The author of the above post is a thinkbroadband staff member. It may not constitute an official statement on behalf of thinkbroadband.
Standard User TheEulerID
(committed) Fri 06-Nov-15 10:04:38
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Re: Lightning Protection Pot (LPP) removal - safe?


[re: ajdroberts] [link to this post]
 
It's not just telephone lines. My parents had several electrical devices "fried" when lightning struck their overhead power supply.

I'm not sure how effective any lightning protection is. If the strike is close enough it will fry pretty well anything.

Furse make a plug-in lightning protection device for phone lines. It's rated up to 15Mhz, so I assume it will be fine with ADSL2 & FTTC (insofar as in the UK the VDSL frequencies used don't go that way). However, it's damned expensive and costs as much as a medium priced modem.

http://cpc.farnell.com/furse/esptn-b1s/telephone-lin...


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Standard User partial
(experienced) Fri 06-Nov-15 10:43:20
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Re: Lightning Protection Pot (LPP) removal - safe?


[re: ajdroberts] [link to this post]
 
If you have only 100m of overhead, you wouldn't fit lightning discharge tubes so I wouldn't worry about it. You fit them on long overhead runs.
Standard User ajdroberts
(newbie) Fri 06-Nov-15 11:12:39
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Frying tonight


[re: TheEulerID] [link to this post]
 
In reply to a post by TheEulerID:
It's not just telephone lines. My parents had several electrical devices "fried" when lightning struck their overhead power supply. If the strike is close enough it will fry pretty well anything.


Yes - If you play golf you will know all this but consider the facts:

Each year, on average, 3 people die from lightning strikes in the UK (14 in 1984).

A typical lightning bolt can bridge a potential difference (voltage) of 200-300 million volts and develop a peak current of 10,000 amps.

Proximity to water such as a pond, stream or the sea increases the risk of being struck by lightning - I have all these things.

Having already had my first lightning strike I shouldn't be expecting a second but when the clouds gather and the rumbling starts I always disconnect the faceplate from my master socket and repalce it with an old wired handset for the duration. I also have my PCs connected to the mains via an APC UPS which I think helps isolate them from a mains cable strike.

When BT buried the 500m of overhead that was hit by lightning I decided to pay my electricity distribution company (the equivalent of BTO) quite a lot of money to also bury their cables on my land (a farm) so as to be safer and tidier. Remember the John Cleese hi-fi 'spaghetti' advert?

Now I have no overhead power cables between me and my 11,000v - 415v transformer, or to the exchange - other than that remaining100m of pole-to-pole about 500m away.

It'd be typical if that section got hit again and cooked me or my hardware..
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