[Elecraft] A dumb question about lightning

[Fred Jensen]

Be very careful of advice regarding lightning protection.  There are 
some very good sources, starting with the NEC and including material 
from ARRL.  Some is somewhat non-intuitive.  For example, the NEC 
requires that any additional "earth electrodes" [aka ground rods] be 
bonded to the service entrance earth electrode with a low inductance 
path. There's been quite an array of advice circulating here recently, 
much of it wrong, some dangerous.

73,

Fred ["Skip"] K6DGW
Sparks NV DM09dn
Washoe County

Geoffrey Feldman wrote on 7/28/2023 5:02 PM:
>   
>
> First thing and foremost - switches are mostly not relevant to protection.
> Energy that can travel 1000' through the sky is likely to continue across
> most switches.   So, the utmost of safety is what you indicated you did -
> disconnect.  By disconnect, I mean either disconnect outside the building,
> leaving the feed on the ground or leave the feed connected to a copper plate
> that is in turn connected to an 8' deep ground stake.  On the inside of the
> house, disconnect the lines from that plate and leave them on the floor.
> Another such stake near the feed point of the antenna is also a great idea.
> If it's possible to lower the antenna when not in use, that's a great idea.
> This should be the default when not in use.
>
>   
>
> You have the belief that no grounding system is perfectly effective (for all
> imaginable strikes) - maybe, but a good grounding system is far better than
> foolishness.   A grounding system, or an antenna is not a "lightning
> magnet". If it doesn't strike it won't. If it does it will and the grounding
> system assures the energy will be less likely to cause harm. Some places and
> circumstances are more or less likely but everywhere is possible.   If that
> possibility happens, a good grounding system is why it is likely to be
> survived.
>
>   
>
> A key thing to understand is that when Lightning strikes in nature, all the
> energy travels along the surface of the ground.  It can do this for many
> feet and be lethal doing it.  Anything that stands along the radius from the
> point of the strike (one part closer and the other further) is in danger.
> Four legged animals, having more distant contact points, more dangerous.
> The purpose of a ground stake (8' straight down) is to channel the
> electricity deep, rather than along the surface.
>
>   
>
> Don't use emotional theories.  Read the lightning mitigation and grounding
> books offered by the ARRL. Use UL approved conductors and stakes.  Do not
> use your homes electrical service ground stake. Keep that separate.
>
>   
>
> All the above is a "cliffs notes" and so is anything else posted here. Read
> the books.  Ask senior members of a local club,  to review your plan.
>
>   
>
> W1GCF Geoff
>



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