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[Weaver]

There have been a lot of storms around recently, and then out of nowhere a single strike on the Red Cuilfhionn, possibly on Beinn na Caillich or on Beinn nan Càrn as that would put it nearer to me. Took out one of my DLink DSL-320B modems, but thank goodness the router was spared. Have ordered a replacement modem from Andrews and Arnold, went out by Royal Mail First Class.

Since there was no warning in the form of a more distant strike first, and no strikes later, I wonder if there is anything I can do to alert me to the danger. An old-fashioned gold-leaf electroscope ?

[burakkucat]

Hmm . . . I have memories, from school days, of cranking up a Wimshurst machine and having all the gold-leaf electroscopes, on a shelf at the other side of the laboratory, responding in unison to each discharge. 

Seriously, have you considered investing in one solid copper earthing spike and six gas discharge tubes? In other words, why not do as Beattie Bellman does? I am unaware of any telephone exchange being "taken out" by a near-by lightning discharge.

[Weaver]

@burakkucat - unfortunately it may be beyond my physical limitations getting gas discharge tubes put in. And would that be enough? What about modest amps for a short(ish) period of time?

I don't need to protect modems, at £20 per device. I am still interested in the fibre media converter thing. I _do need_ to protect Fibrebricks at £700, WAPs various at £50-£700, servers, larger switches and so on.

I intend to treat modems as expendables, total cost 3 × £20, if I go for the VLAN switch idea then the VLAN switch is also expendable as its on the death zone side of the fibre media converter pair.

The other option is insurance esp. before I can get fibre in to break the copper before the Firebrick. I intend to buy a fair sized lump of insurance.

Downtime: I'm thinking of having a second Firebrick and some more modems to minimise downtime. I am lucky enough to have excellent 3G (EE is 4.2 Mbps d/s, u/s is vg too) times two - Andrews & Arnold 1 static IPv4 address over Three,  and EE too. Unfortunately, the basestations go down when the mains electricity goes down.

[burakkucat]

@burakkucat - unfortunately it may be beyond my physical limitations getting gas discharge tubes put in. And would that be enough? What about modest amps for a short(ish) period of time?

Hmm . . . Perhaps we need to consult a technician from BT Operate (the exchange equipment people), not BT Openreach (such as Black Sheep). My understanding is that there are fast acting gas-discharge tubes, one for each leg of a pair, followed (i.e. towards the electronics) by fast acting fuses in the hundreds of milli-ampere range. Upon striking (at about 95V) the gas-discharge tubes "crowbar" the legs to a very low impedance earth

I don't need to protect modems, at £20 per device. I am still interested in the fibre media converter thing. I _do need_ to protect Fibrebricks at £700, WAPs various at £50-£700, servers, larger switches and so on.

Nods.

I intend to treat modems as expendables, total cost 3 × £20, if I go for the VLAN switch idea then the VLAN switch is also expendable as its on the death zone side of the fibre media converter pair.

Have the modems and VLAN switch located in an appropriately earthed steel enclosure bolted onto the outside of the building, so that you only have the fibre and a mains spur (with its own ELCB) to power the gubbins linking inside and outside of the building?

. . . I am lucky enough to have excellent 3G (EE is 4.2 Mbps d/s, u/s is vg too) times two - Andrews & Arnold 1 static IPv4 address over Three,  and EE too. Unfortunately, the basestations go down when the mains electricity goes down.

I would have thought that the base stations would have some form of battery backup and could possibly be powered by their own, individual, wind turbines.

[Weaver]

If I were one of the men in power, I would want to insist that 3G basestations have backup power. Round here people on the mountains and out at sea rely on GSM / UMTS and having yet another critical service go down when there is bad weather is not good enough. The basestations could have a UPS and a Diesel generator. I am not sure if wind is reliable enough, it might easily be too windy as well as not windy enough. I believe some wind generators take some kind of action for self-preservation well before the winds reach 130mph.

[benji09]

   Weaver, do you use mains surge protecters on your equipment ?  I assume that because you live miles from anywhere, that your mains supply is provided without  a mains earth and your earth pins of your sockets terminate to the neutral wire at the fuse box - incorrectly termed - PME supply, and therefore you probably have a mains earth spike outside your home ?  Do you know what part of your routers get destroyed by by lightning ? Do you get any corded type telephones destroyed by lightning strikes ?

 

[Weaver]

>do you use mains surge protecters on your equipment

layer upon layer of mains surge protection: a primary £40 Belkin device nearest the wall socket , then a UPS, then another layer of mains protection (Belkin again),  and for the modems only, a third layer of filtering (Tacima).

Indeed as you say, neutral is connected to earth.

When I lost a router a few years ago, it was just dead, I'm afraid I know no more than that, not one port gone. I lost a £2.5k server, completely doa, not a dead NIC. That was not good. Hard disk was fine, thank heavens.

The latest dead DLink modem could even be just a dead PSU, no lights at all on it. The port on the router is fine as I swapped in another modem as a health check.

Afraid I don't use a corded phone. All three lines are effectively DSL only, although I can do the usual quiet line test diagnostics, I keep a POTS phone for that.

[jelv]

http://www.lightningmaps.org/realtime?lang=en is great for monitoring lightning in real time.

The other maps show the last 24 hours and you can zoom right in to see where a lightning strike actually was.

Was it the one just north of Sgurr Alasdair?

[Weaver]

I use lightningmaps.org it was on Monday around midday. The strike was shown on the map as being in the area of Glamaig - Blà-Bheinn - Beinn na Caillich. Because it caused me some damage, I would have guessed at the latter. My house is on the eastward slope of Beinn na Caillich, about 400 ft up.

[benji09]

Weaver, I think you have covered everything concerning lightning protection that I can think of !  I think somewhere else in the forum, somebody mentioned a Gas Discharge Tube 21 fitted to an NTE No 5 at your premises to shunt lighning surges - not strikes - to earth. Perhaps a word with your local BT area, if you have not done so already, may allow one or more to be fitted at your home. But I am not sure if they would be compatible with broadband.
  Incidentally some years ago, one of our customers had some of our computer type equipment fitted at their site. A radio transmitter mast was also fitted at the site. The inevitable happened, and the mast was STRUCK by lightning. This lightning strike caused our equipment to fail. After a time, the engineer that had been called to the site, realised that the main equipment was OK but a number of VDUs had damaged inputs. Of course, the VDUs were the only items directly connected to the mains supply........ 

[Weaver]

Some inline devices are not compatible with weak (high attn) DSL. I tried an APC inline device years ago, ruined the signal quality and the achievable sync rate was dreadful.

[Weaver]

The dead modem has now been replaced by another unit of the same type.

The dead unit was not only dead (no lights) but its PSU was dead too.

[benji09]

  Well your lightning surges definitely do some damage to your modems !  Bear in mind that although a modem might be damaged by being plugged into a BT line, it maybe that the surge was actually on the mains supply. It was for this reason, I asked if you have a good, low resistance, working earth spike outside of your property, going back to your mains supply's neutral/ protective earth connection.
  I also come back to previous point about listening to a long wave radio, as by doing so, you may often hear when things start hotting up outside, even before a storm hits.

[jelv]

Does long wave get affected by the build up of charge before there are any lightning discharges or are you only suggesting it as a way of detecting lightening that is too far away to see/hear? If it's the latter http://www.lightningmaps.org/realtime?lang=en is far better (I can tell you for instance that at this very moment there's a storm in the Amsterdam area and there's also quite a few storms in the Guatamala/Nicaragua area).

[Weaver]

I don't have an earth spike at the property. It's so-called PME.

For anything to get through the mains to the modem (which has no earth pin), it would have to breach three levels of anti-surge protection (with MOVs) and get through a UPS too.

I use lightningmaps.org all the time but I'm thinking of getting an alarm with an audible warning.