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Posted By: George Little Ground Rod - 10/17/04 04:45 PM
What are the required dimensions for a galvanized steel rod if it is to be used as a gounding electrode? Trick question.
Posted By: iwire Re: Ground Rod - 10/17/04 04:50 PM
I will take a swing at this.

5/8" x 8' minimum.
Posted By: gfretwell Re: Ground Rod - 10/17/04 04:55 PM
Ah the new Galvan Electric rod huh?

If U/L is OK with it I am OK with it ... until someone tells me otherwise.
Posted By: Ryan_J Re: Ground Rod - 10/17/04 05:13 PM
I agree with Bob.
Posted By: iwire Re: Ground Rod - 10/17/04 05:13 PM
Wouldn't we have to wait for 250.52(A)(5)(b) to get changed?

Quote
250.52(A)(5)(b)Electrodes of rods of iron or steel shall be at least 15.87 mm (5/8 in.) in diameter. Stainless steel rods less than 16 mm (5/8 in.) in diameter, nonferrous rods, or their equivalent shall be listed and shall not be less than 13 mm (1/2 in.) in diameter.

In my mind a galvanized steel rod is not equivalent to Stainless steel or nonferrous rods.

Bob
Posted By: George Little Re: Ground Rod - 10/17/04 05:29 PM
Boy, you guys are right on top of your game. Yes it is all about the Galvan Electric rod. 250.25(A)(5)(b) is kinda poorly written (surprise, surprise) and hopefully it will get re-written someday. In talking with NEMA rep. they use the word "nominal" meaning something in name only when talking about a 5/8 ground rod. Actual dimensions are considerably less than 5/8". The Galvan rod is also less than 5/8" but it has the blessing of UL and I am not sure but maybe we should lean towards using this listed product rather than using and approving the "nominal" 5/8" rod.
Posted By: e57 Re: Ground Rod - 10/17/04 06:16 PM
I remember the last time this rod was talked about, and the site like had a whole "justification" page about thier listing, and sizing.
http://www.galvanizersonline.com/electrical/faq.asp

George, do you have stock in this company? [Linked Image] I don't get the reason why this would be better than a "regular rod"?
Posted By: iwire Re: Ground Rod - 10/17/04 06:26 PM
From their site.

Quote
What does the NEC Code say about ground rod electrode diameters?

Diameters must be 0.625 inches minimum and the rod length must be 96 inches (8 feet) minimum. Any rod less than 0.625 inches DOES NOT meet the NEC Code, unless it is “listed.” Galvan has achieved this compliance!

What I don't understand is the compliance with "equivalent to Stainless steel or nonferrous rods."

Who decided a galvanized rod is equivalent and if it is what type of rod would not be equivalent?
Posted By: CharlieE Re: Ground Rod - 10/17/04 06:34 PM
This reminds me of the question, "What is the inside diameter of 1/2" conduit?" [Linked Image]

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Charlie Eldridge, Indianapolis, Utility Power Guy
Posted By: George Little Re: Ground Rod - 10/17/04 07:36 PM
To answer e57, I don't have stock in Galvan, wish I did. This question came up at one of our local inspector forums and got us all talking. I have invited the rep for Galvan to our IAEI Annual Michigan Chapter meeting in December and gave him a 15 minute part on the program to clear up the matter. Somehow I doubt 15 minutes will get it.
Posted By: Dave55 Re: Ground Rod - 10/18/04 01:02 AM
I'm with Bob on this one. Galvanized steel is ferrous, so the first sentence of the applicable code applies. A galvanized steel rod (ferrous) isn't equivalent to a non-ferrous rod.

Dave
Posted By: John Steinke Re: Ground Rod - 10/21/04 02:10 AM
As far as I'm concerned, Galvan is hyping a non-issue. As I read the code, ANY 5/8 piece of steel or iron may be used as an electrode- even pipe or structural iron.

I think you'll find that stainless steel is not as conductive as "regular" steel.
I have had concrete workers claim that rebar isn't galvanised because the zinc damages the concrete as it decomposes; I have seen zinc deteriorate quickly in concrete and alkali soils.

I've always wondered why we just don't use #5 re-bar for our ground rods- and save the $$$. (After all, re-bar is the basis of the Ufer grid).
Posted By: InspectorE Re: Ground Rod - 10/23/04 01:10 PM
An interesting product is Conducrete, which is electrically conductive concrete. It can be used around ground rods/rings to increase their conductivity plus it claims to limit corrosion. It is made by SAE Inc. This is pricey stuff (~$50/55 pound bag) but may be an answer for a tough location or a customer with severe conditions. I'd like to see some independent testing lab make some measurements of this product.
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