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Posted By: poorboy Ground rod at pole base - 07/02/05 09:55 AM
If you have a 10 foot high by 24 inch diameter concrete light pole base, 1 inch anchor bolts sunk into it a couple feet, and 7 feet of the base below grade, what is the actual mentality behind driving a groud rod next to it and having a #6 ground wire to the pole. Is it because the connection obtained by tightening down the 4 large nuts onto the steel or aluminum light pole is not a real good connection, or that the 2 feet of anchor bolt is not deep enough into the concrete, or that concrete is not a good earth ground? I have seen specs before where a copper ground wire was to be connected to rebar in the concrete base,to cover this, is that as good as a ground rod? (and what would be the best way to connect to the rebar?)

There is an equipment ground already in the conduit, so is this local rod to dump lightning or what?
Posted By: luckyshadow Re: Ground rod at pole base - 07/02/05 07:57 PM
I have done many projects just as you described. The specs for the jobs always call for the ground rod. I always assumed that it was for lightning protection.

Connecting to rebar - try exothermic welds.
I use " cadweld"

Ken
Posted By: Trumpy Re: Ground rod at pole base - 07/06/05 02:13 AM
Personally I'd never use the rebar in a concrete pole as a Grounding conductor.
The chemicals in concrete can rust away steel rod without it being noticed.
Besides, copper is a much better conductor.
Posted By: Scott35 Re: Ground rod at pole base - 07/09/05 08:42 PM
You know who this topic reminds me of?

Good 'Ol Benny!

He posted a detailed message - somewhere, some time ago, which covered the reasoning behind additional "semi-deep" Earthed Electrodes at Lighting Pole Standards' base assemblidges.

It also addressed the reasoning behind why NFPA views it as a Separate Structure (a Concrete Lighting Pole Base) and worthy of a supplimental Electrode.

I just have no idea whatsoever, where this message is located, whaddaheck the topic's name is, even which forum it was posted!

Made a pasted text file copy of the post, and guess what... I don't know where to find it either!
D'Ohh!!! [Linked Image]

Quote


(Me Thinking):

Is it on this machine... maybe it's on one of the drives of the server?... maybe at work... or on the backup machine???... maybe it's on one of the 1,024,056 floppy disk archives?... maybe in a Zip Archive somewhere... maybe on a CD-R, or maybe it's......... did I make a hard copy?...


Shedding a slight tear for the departed Benny.

Scott35
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