Bill MacLane wrote:
> The service entrance grounding conductor required by the NEC is for safety,
> not rf grounding, not lightning protection, only safety. Properly installed
> grounding conductors are to prevent a fault current from burning up things
> (including your house) or flowing through ones body.
>
A good ground fault detector will do the latter, but not a good ground.
New systems use GFIs that are sensitive enough to grab the wires without
feeling a shock (they tell me) and I've seen a demonstration. Me? I
don't have quite that much faith in them.
> A good RF ground system is bonded to the service entrance electrical ground
> rod for the same reason. A good ground system made of several ground rods,
> copper strap and radials and it will dissipate a strike, but it will not
> assure complete safety from a strike. I know. I rebuilt many commercial
> radio transmitters, STL, and microwave links (as well as a station) after a
> strike and every station had tons more copper burried than any ham radio
> operator's shack. Recently there was a series of articles on lightning
> protection in QST. I have also run across some on the internet.
>
>
I'm using 32 or 33(lost count) 8' ground rods, cadwelded(TM) to over
600 feet of bare #2 copper. That also ties into the house electrical
system as added protection for the house. The top of the system is at
130 feet and it's taken quite a few *verified* direct hits. Until last
year it was averaging 3 a year, but non last year and none this
year...so far. I should add, there are lightning strikes and then there
are lightning strikes. All strikes are not created equal and I doubt
much is going to withstand a direct hit from one of the so called super
strikes. Actually I have two complete systems tied together. The shop
and house have separate electric feeds and panels, but all of the ground
systems are tied together into one very large network. And yes, I did
that before copper went up over five times its value in 2000.
73
Roger (K8RI)
> 73,
> Bill
> AI4WM
>
>
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