----- Original Message -----
From: "William Q Meeker" <wqmeeker@iastate.edu>
To: <towertalk@contesting.com>
Sent: Monday, March 14, 2005 4:12 AM
Subject: [TowerTalk] grounding radials: solid or stranded?
>
>
> I am trying to work out a few details for my lightning protection system.
>
> I have received and read (some in the TT archives) some conflicting
> recommendations on whether to use solid or stranded copper wire for ground
> radials (which will connect to ground rods, appropriately spaced along the
> radials). The electrical service ground for our house uses #4 solid copper
> wire.
Which would be what the local code probably requires for the electrical
safety ground. (but that's NOT a lightning ground)
>
> It has been suggested that stranded copper wire would have little less
> inductance and thus be more effective.
The inductance of stranded and solid wire will be almost the same (as in, I
doubt you could measure it easily). You may be thinking of Litz wire, which
has separately insulated strands, and which does have lower skin effect
losses. But not necessarly lower inductance.
>I suppose, however that longevity of
> stranded copper underground might be less, especially if the soil is
acidic.
That depends on a lot of things. One advantage of stranded wire in some
applications is that some of the strands can break or corrode and you still
have a connection (burglar alarm wiring is a good example). Stranded wire
is also more flexible.
>
> Is there a clear choice or is this the trade-off that one needs to
consider?
Bigger wire is better. Big solid wire is hard to handle. The lightning
conductors I've seen have all been fairly large stranded wire (in the 2/0
and up size)
>
> I am planning to use copper strap to run from the first ground rod to each
> of the tower legs.
>
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|