Grounding Conductor

[vennivivi]

Hi,

I intend to use stainless steel wire instead of copper as grounding conductor. I understand that copper is a far better conductor than steel. Is there any regulation which prohibit the use of stainless stell as earthing conductor?

Thanks for any advice.

Grundig

 

[7anoter4]

If you mean "grounding rods", the stainless steel is better if the Grounding Grid horizontal laid conductor is lead or tin covered [in order to avoid foundations rebar corrosion]. Stainless steel instead copper for horizontal electrode is not indicate due to high resistance and so elevated temperature when shortcircuit current will flow through.

 

[waross]

Many codes require that all electrical components be approved by a recognized agency. I am not aware of approved stainless steel conductors. I would be interested to know if you find that approved stainless conductors are available.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[Guardiano]

Hi,

I came across this thread while googling for earthing conductors. Although stainlees steel is not used as horizontal conductor as per coded practice, stainless steel IS widely used as grounding electrode. I believe that because of the physical properties of stainless steel as electrical conductor,stainless steel should not be favoured as grounding electrode.

Guardiano

 

[jghrist]

By "grounding conductor" do you mean a part of a grounding grid electrode system or an equipment grounding conductor?

 

[DanDel]

The NEC 250.62 states:

Grounding Electrode Conductor Material.
The grounding electrode conductor shall be of copper, aluminum, or copper-clad aluminum. The material selected shall be resistant to any corrosive condition existing at the installation or shall be suitably protected against corrosion. The conductor shall be solid or stranded, insulated, covered, or bare.

Sizing is based on table 250.66, which just contains sizes for the above-mentioned materials.

If your installation is in the USA, you can't use stainless steel wire.

 

[BJC]

Re Stainless Steel Ground Rods.
There have been several papers written on corrosion in stainless steel ground rods. It was a from of stress corrosion. A copper or copper coated ground rod corrodes efenly over it entire surfacel Astainless rod is subject to inter granualr or stress corrosion an all the corrosion may occour in a localized area and got through the rod.
I have the articla somewhere, it convinced me never to use stainless ground rods.

 

[Guardiano]

Thanks Dandel for the code. BJC, as far as intergranualr corrosion is concerned, stainless stell 304 or 316 has a very low carbon level, generally less than 0,03 %,and is relatively much resistant to the precipitation of carbide.Anyway, many thanks for raising these point.

Guardiano