[TowerTalk] FW: Tower Grounds

[Clay Autery]

A good question, Jim...  I suppose the though is that the stainless 
steel through bolts that bolts the powdercoated steal clevis to the 
foundation rod and the aluminum tower legs, are a) not copper/aluminum 
and b) may not have the best of electrical interfaces with the tower 
leg.  But since you mention it, I will consider doing some testing to 
see what the actual measurements are...  Not sure I want any arcing 
between the bolts and aluminum through holes in my base section 
though...  I'd prefer no arcing at all if possible.  But I get your 
point.  Those bolts are very attractive...  and the steel threaded rods 
protruding 6 foot into the concrete foundation also look mighty 
attractive for additional bonding points assuming they were properly 
bonded to the rebar cage and the rebar cage were properly welded 
together...  Things to think about.  Would be much easier to construct a 
brazed lug end from the strap end than to make it conform to a round 
tower leg, etc...

Feedline grounding to the tower is a whole 'nuther animal...  I won't 
pollute this thread by drifting to that.  <grin>

73,

______________________
Clay Autery, KY5G
MONTAC Enterprises
(318) 518-1389

On 10/17/2017 9:31 AM, jimlux wrote:
> Why not just a lug on one of the bolts? Good clamping force, good 
> electrical connection, etc.  If you've already bolted the base to the 
> rods, is there enough to put a lug and a second nut on top?
>
> This brings up an interesting point, why is everybody talking about 
> making "clamps" of some sort to clamp onto a structure which has 
> bolted joints?  I can see needing a clamp when you're grounding a long 
> length of hardline that you don't want to break for a connector.  And 
> I've seen clamps on things like chain link fence posts (typically so 
> that the gate is bonded to the rest of the fence - the fence posts are 
> set in concrete in the soil, so they *are* a grounding electrode)