Good advice from 7lm. The damage I have had a-plenty over the past twenty years has I believe been from either stray induced currents or else GPR/EPR - something that people forget about all the time. With such a long line I would suspect that GPR/EPR is a serious danger and I would think that it brings on slow cooking rather than dramatic damages.
As for direct lightning strike, I have several enormous trees right near the house; I would think they act as lightning conductors and I would expect them to be much more tasty for a direct close strike.
I would need to find some serious engineer with a reputation backed by evidence who could arrange what - gas discharge tubes? - for the dsl lines and for the mains. It would probably cost a fortune.
My current strategy - no pun intended
- warning system hardware,
- warning app for iOS and real-time lightning map
- spares
- proper insurance.
- mains surge protectors
I have two warning systems and maps (i) a Skyscanner hardware lightning warning system with a range of about 120mi or so; it’s ridiculously sensitive which is very good as it gives you hours of warning to check maps if strikes. The only bad thing about it is that I can’t seem to get the beep sound alert to work. It flashes lots of bright lights.
(ii) The second warning system is an iOS app "Lightning Tracker Pro" which warns me of strikes in a particular chosen radius and displays a real-time updating map. The app is running on two iPads now it give me a better chance of hearing / seeing the alert notifications. (iii) I also have a web-based strike map at lightningmaps.org and blitzortung.org. I know these things work because I can check the iOS Apps against the web maps and against the hardware SkyScanner unit and I can hear the thunder at the correct time according to the sound arrival radial picture in the optional blitzortung thunder map.
Mains protection: lots of surge protectors based on the fattest MOVs I can find expensive Belkin audio-video units and also a pair of UPSs which are supposed to provide surge protection.
With
spares there is no downtime, and serious insurance removes the financial shock. I have more than a complete set of replacement spare modems, I have a second small mux switch on order should be here On Saturday and I have a spare Firebrick.
I have checked that our insurance covers lightning damage and once began to make a claim but never went through with it as that was the time that AA gave me a free replacement Firebrick FB2700. So the insurance is thus far untested.