ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals

Topic Options
Rate This Topic
#129669 - 07/02/05 02:55 AM Ground rod at pole base
poorboy Offline
Member
Registered: 06/02/05
Posts: 124
Loc: Central Maine
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?
Top
Tools for Electricians:
#129670 - 07/02/05 12:57 PM Re: Ground rod at pole base
luckyshadow Offline
Member
Registered: 01/04/05
Posts: 305
Loc: Maryland USA
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
Top
#129671 - 07/05/05 07:13 PM Re: Ground rod at pole base
Trumpy Offline


Member
Registered: 07/05/02
Posts: 8211
Loc: SI,New Zealand
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.
_________________________
Let's face it, these days if you're not young, you're old - Red Green grin
Top
#129672 - 07/09/05 01:42 PM Re: Ground rod at pole base
Scott35 Offline

Broom Pusher and
Member
Registered: 10/19/00
Posts: 2707
Loc: Anaheim, CA. USA
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!!!

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
_________________________
Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!
Top

Member Spotlight
Member Since: 01/22/05
Posts: 5316
New in the Gallery:
SE cable question
Featured:

2017 NEC and Related
2017 NEC
Now Available!

Shout Box


Who's Online
0 registered (), 65 Guests and 12 Spiders online.
Key: Admin, Global Mod, Mod
 
New in the Gallery:
SE cable question
 
Top Posters (30 Days)
Admin 47
HotLine1 43
gfretwell 19
Ruben Rocha 12
Trumpy 9
 
Newest Members
Scotto, Freecrowder, clee512, Jdscott2005, FAIZAN

ECN Electrical Forums - sponsored by Electrical Contractor Network - Electrical and Code Related Discussion for Electrical Contractors, Electricians, Inspectors, Instructors, Engineers and other related Professionals