Industry Forums > Wireless Service Providers > Grounding equipment to tower

Grounding equipment to tower

A 3 1/2" tower is awfully short! LOL

Cadweld is the only way to go.

Heh You should read the entire message before you make a smart ass reply. You just might get one your self

reply to Diddy1
okay, I'll give a more serious answer this time. I guess some people don't like my smart ass ones, guess I can't blame them.

On small towers like Rohn 25 I use brass clamps, but I don't know whats available along those lines for a larger tower leg. All the big towers I work on generally have ground lugs welded to the legs that you can either bolt a ground wire to or use Cadweld.

Cadweld is always the best way to attach grounding components.

reply to Diddy1
I agree exothermic welds are best.

Another option is wide stainless steel strap tightened with a professional tool used by the packaging industry. It is used widely by cellular companies and WISPs in poor countries like Bangladesh and India.

reply to Diddy1
wrap-lock? I suppose that would work, never thought of using it for that.

reply to Diddy1
Tessco carries ubolt type devices.

»www.tessco.com/products/displayP···e&page=3

Bottom portion of the page. I have been using them the last 3 weeks doing grounding jobs myself. Bronze attachment point, stainless ubolt and hardware, hot galv'd backing plate. Don't forget the Burndy Penetrox-A or Harger copper joint compound to grease the wire connection points and the stainless hardware so you do not gaul it when tightening it.

EDIT:

NEVER EVER EVER Cadweld to a tower where it is not specified by the tower manf. When you exotherm weld to a tower, there is always a welded plate or spot that is provided by the tower maker for you to attach your weld. Welding to a tower where it is not specified can damage the tower, and cause catastrophic failure.

--
"No job is so important, and no service is so urgent that we cannot take the time to do it safely."
-- AT&T
--Safety One Tower Rescue Certified
--LLigetfa:"Wimax is like teenage sex. Everyone talks about doing it."

reply to LLigetfa
I think you missed the meaning of the "Heh" and the trailing ":)"

I don't think I would do a cadweld directly to the tower.

Well... 3 1/2" I assume to be either the width of angle iron or the diameter of round tubing, so it should be substantial enough to cadweld to but, by all means, check with the tower manufacturer first.

BTW, cadwelding is not really "welding" as in welding of two equal elements. It is just brazing, as the metal on the tower leg is not actually being melted and the heat shock is much less than that of arc welding or even torch brazing.
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Strange as it seems, no amount of learning can cure stupidity, and formal education positively fortifies it. -- Stephen Vizinczey

Actually Cadweld and other copper oxide exothermic reactions reach much higher temperature (1000C) than brazing (450C). That's why they make much better joint with higher current carrying capacity.

reply to battleop

reply to lutful
I would dispute those numbers as exaggeration. At least one document I found say the melting temperatures are about the same but the overall temperature may spike slightly higher.
»www.exoweld.co.za/contentpage.as···geid=519

While the spot temperature may be slightly higher, the high speed process results in less heat overall on the area. I have done many connections on high pressure gas pipelines for cathodic corrosion protection systems using cadweld, silver solder, and brazing. Soldering and brazing takes a lot more time and the base material is more prone to annealing.
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Strange as it seems, no amount of learning can cure stupidity, and formal education positively fortifies it. -- Stephen Vizinczey

Great to see so much discussion, but I need to clarify what I need.
Were mounting 1 radio 75' up, the tower legs are 3 1/2". This is a temporary setup and installers recommend grounding to tower as radio will be below 10' dish. Let's not get into the proper grounding arguement LOL as this is just temporary.

Aaron

You do not want to try exothermic welding at 75'. Use a beam clamp to the angle tower leg and the a lug and wire to the beam clamp. Easy and functional.

reply to Diddy1
Again, use the clamps I listed in the link. They will be fine for what you need.

And Superdog is right. Depending on how the tower was built, the joints might not be very high quality and you may experience poor connectivity to ground.

reply to Diddy1
for temporary i would just clamp it to the leg. for a permanent install i would put a ground bus bar up there, and run some #4 down the leg to the tower halo.

as far as just clamping, we put a ground clamp on feedlines at most every 100' apart, and these are just clamped to the tower leg. if that is enough to satisfy the big M ofr a permanent ground, it should be more than enough to meet your needs.
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Lack of Preparation on YOUR Part does NOT Constitute an Emergency on Mine!

reply to Diddy1
It would have been nice to know you were grounding equipment to the tower leg, and not grounding the tower leg to the earth ring. Up until this revelation, the discussion was around the latter, not the former.

Since the ground is not expected to carry the full current of a direct hit, the rules change as does the gauge of wire. It still isn't clear whether the tower leg is angle iron or round and the means of attachment could vary depending. On a round member, I would go with multiple stainless steel straps (hose clamps) or U-Bolts. If it is flat stock, I would use beam clamps to sandwich a gound plate to the leg.
--
Strange as it seems, no amount of learning can cure stupidity, and formal education positively fortifies it. -- Stephen Vizinczey