Oh! And I see Hargar makes a rebar clamp!
http://www.harger.com/products/idx.cfm?subc4id=256&p=1&oiid=824&thid=690&footid=0&footinfoid=0
73
Jim W7RY
--------------------------------------------------
From: "Jim W7RY" <w7ry@inbox.com>
Sent: Sunday, April 17, 2011 7:07 PM
To: "Mat Eshpeter" <kk1c@live.com>; <towertalk@contesting.com>
Subject: Re: [TowerTalk] grounding quesitons: Ufer, strap, exothermic welds
> The problem is that strap can decay and degrade over time directly in some
> types of earth AND As you have pointed out, connection to strap is
> problematic at best unless it is also welded (brazed using silver bearing
> welding) The only place I recommend strap is between the external
> grounding electrode system and the building coax entrance panel. Harger
> http://www.harger.com/ makes a special welded system to transition the
> strap to a copper bar and then it's cad welded to the #2AWG bare tinned
> grounding system.
>
> Most communications sites (cellular and public safety) use #2 AWG tinned
> underground conductors that are exothermically welded together. Some
> Federal Government installations may have specifications that require
> larger wire. But over the years, solid tined wire has proven to be the
> best.
>
>
> 73
> Jim W7RY
> Motorola Solutions
>
>
>
>
>
> From: Mat Eshpeter
> Sent: Sunday, April 17, 2011 9:34 AM
> To: w7ry@inbox.com ; towertalk@contesting.com
> Subject: RE: [TowerTalk] grounding quesitons: Ufer, strap, exothermic
> welds
>
>
> Jim - what about the inductance of wire? The reading I have done strongly
> suggests that lightning is better handled with solid strap because of its
> low inductance versus wire. Lightning is supposed to be broadbanded with
> most energy centered around 1MHz so strap is supposed to be "king" for the
> purposes of dissipating lightning.
>
> 73,
> mat
>
>> From: w7ry@inbox.com
>> To: kk1c@live.com; towertalk@contesting.com
>> Subject: Re: [TowerTalk] grounding quesitons: Ufer, strap, exothermic
>> welds
>> Date: Sun, 17 Apr 2011 07:58:27 -0700
>>
>> I would put some #2AWG tinned solid in the foundation and not rely on the
>> rebar.
>>
>> I have used a clamp type unit to clamp the copper strap to the ground
>> rod.
>>
>> If it's lightning your concerned with, I would not use strap. Stick with
>> #2AWG tinned bare copper, copper clad rods and exothermic attachment.
>>
>> 73
>> Jim W7RY
>>
>>
>> --------------------------------------------------
>> From: "Mat Eshpeter" <kk1c@live.com>
>> Sent: Sunday, April 17, 2011 7:24 AM
>> To: <towertalk@contesting.com>
>> Subject: [TowerTalk] grounding quesitons: Ufer, strap, exothermic welds
>>
>> >
>> > I am about to pour concrete for the base of my HDX589 tower. I am going
>> > to
>> > go with a Ufer ground as well as the Polyphaser recommended eight 75'
>> > radials with multiple ground rods (8' rods every 16'). Location is on
>> > top
>> > of a 1600' ridge in WV and lightning is a very real concern. My QRZ web
>> > page gives a feel for the location.
>> >
>> > To build the Ufer ground, I am thinking about connecting a single bare
>> > 2/0
>> > stranded copper wire to the rebar. Questions:
>> > 1) is one enough?
>> > 2) how do I properly connect the copper to the rebar? Is exothermic
>> > weld
>> > the only way? Any problem with dissimilar metals?
>> > 3) how should the copper exit the base slab - above grade or below
>> > grade?
>> >
>> > Also, seems that copper strap is the preferred ground material for
>> > connecting rods together. Will 0.032" thick strap have significantly
>> > better longevity than 0.022" strap? I am refering to the strap sold by
>> > Georgia Copper. Copper is expensive and I don't want to invest in
>> > copper
>> > that won't add any value to my installation.
>> >
>> > Where can I find exothermic weld products to connect copper strap to
>> > 5/8"
>> > copper clad ground rods? I am exhausted reading Harger, Erico,
>> > Terraweld
>> > info, and can only find wire-to-ground rod products, no strap-to-rod
>> > products.
>> >
>> > 73
>> > Mat
>> > KK1C
>> >
>> >
>> >
>> >
>> > _______________________________________________
>> >
>> >
>> >
>> > _______________________________________________
>> > TowerTalk mailing list
>> > TowerTalk@contesting.com
>> > http://lists.contesting.com/mailman/listinfo/towertalk
>> >
>> >
>> >
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>> >
>
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