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Roland Miller
02-09-2009, 06:10 PM
I inspected a well pressure tank and pump. A small 8 ckt panel was used. It is set underground in a metal culvert. If this is used as the grounding electrode, is it code compliant or is something else required??

Fred Warner
02-10-2009, 01:54 PM
I inspected a well pressure tank and pump. A small 8 ckt panel was used. It is set underground in a metal culvert. If this is used as the grounding electrode, is it code compliant or is something else required??

Roland, when you say "if this", do you mean the culvert itself being used as an electrode? 250.50 in the '08 code says to use 250.52(A)(1) thru (A)(7) where they exist. If none of these electrodes exist, then one or more of 250.52(A)(4) thru (8) shall be installed and used. (8) would be your culvert, right? What's your read on it? :)

Jerry Peck
02-10-2009, 02:04 PM
Fred,

I am envisioning Roland meaning the metal culvert is underground, horizontally placed under something such that at least one end is open for access, with or without doors, in which case the metal culvert could be (2).

If the culvert is installed vertically underground (meaning 'down into the ground') and the 8 circuit panel is 'down in it', several things come to mind: first, accessibility; followed by working space; followed by how deep is the culvert; how far down is the panel; what provisions are there to keep that area dry so the panel does not become submerged in water when it rains; and other such things related to the panel being 'down in the ground in a hole'.

Roland Miller
02-10-2009, 02:20 PM
The culvert is vertical in the ground with a nice cover and access lid with a permanent ladder. The only question is can one use this galvanized steel culvert as a grounding electrode??

Jerry Peck
02-10-2009, 02:41 PM
The culvert is vertical in the ground with a nice cover and access lid with a permanent ladder. The only question is can one use this galvanized steel culvert as a grounding electrode??


I am envisioning Roland meaning the metal culvert is underground, horizontally placed under something such that at least one end is open for access, with or without doors, in which case the metal culvert could be (2).

Okay, it is not horizontal, it is vertical and you climb down inside it, that still makes it a "structure", and it is metal, so ...

- 250.52 Grounding Electrodes.
- - (A) Electrodes Permitted for Grounding.
- - - (2) Metal Frame of the Building or Structure. The metal frame of the building or structure that is connected to the earth by any of the following methods:
- - - - (1) 3.0 m (10 ft) or more of a single structural metal member in direct contact with the earth or encased in concrete that is in direct contact with the earth
- - - - (2) Connecting the structural metal frame to the reinforcing bars of a concrete-encased electrode as provided in 250.52(A)(3) or ground ring as provided in 250.52(A)(4)
- - - - (3) Bonding the structural metal frame to one or more of the grounding electrodes as defined in 250.52(A)(5) or (A)(7) that comply with 250.56
- - - - (4) Other approved means of establishing a connection to earth

Is that culvert 10 feet deep? If so, then 250.52(2)(1) *could* be applied.

Fred Warner
02-10-2009, 02:54 PM
Interesting question. In this sense, at least: is it permissible to install a NEMA 3-R (rain-tight) panelboard and enclosure (assuming working clearances meet 110.26) "inside" of a grounding electrode? :confused: :D

If it were me, I would ask the design professional if he/she thought it better to provide other approved electrodes. Or, of course obtain approval from the AHJ. :)

Roland Miller
02-10-2009, 05:39 PM
The culvert is 10' long by 10' in diameter. Either way it is structural steel (ie 10 feet or more in contact with the earth --doesn't have to be vertical) or it was 8 feet deep so I called it a pipe electrode(galvanized steel) and called it good..:) so I allowed it to be used as the electrode. No need for nema 3R cause it is inside the culvert and cover..and no problem meeting working clearance requirements..

Jerry Peck
02-10-2009, 07:45 PM
The culvert is 10' long by 10' in diameter. Either way it is structural steel (ie 10 feet or more in contact with the earth --doesn't have to be vertical) or it was 8 feet deep so I called it a pipe electrode(galvanized steel) and called it good..:) so I allowed it to be used as the electrode.

If it is not 10 feet long buried in the earth (either vertically or horizontally) then is cannot be considered as 250.52(A)(2)(1), so it would have to meet 250.52(A)(2)(2), (3), (4), or (5) for it to be considered suitable for use as a grounding electrode.

Calling it a pipe electrode would be a r-e-a-l s-t-r-e-t-c-h. :)

Roland Miller
02-11-2009, 11:23 AM
It meets both requirements, structural steel and it is a pipe so there is really no question it can be used as a grounding electrode...

Jerry Peck
02-11-2009, 11:33 AM
It meets both requirements, structural steel and it is a pipe so there is really no question it can be used as a grounding electrode....

"there is really no question it can be used as a grounding electrode"

Then why did you bother to ask the question? :rolleyes:

However, it does not meet the requirements, not as stated in your question or additional information, to meet the structural steel electrode.

Trying to fit that into this ...
- (5) Rod and Pipe Electrodes. Rod and pipe electrodes shall not be less than 2.44 m (8 ft) in length and shall consist of the following materials.
- - (a) Grounding electrodes of pipe or conduit shall not be smaller than metric designator 21 (trade size ¾) and, where of steel, shall have the outer surface galvanized or otherwise metal-coated for corrosion protection.
- - (b) Grounding electrodes of stainless steel and copper or zinc coated steel shall be at least 15.87 mm ( in.) in diameter, unless listed and not less than 12.70 mm (½ in.) in diameter.
... is, as I stated, a bit of a stretch.

I should add, though, that it appears if anyone thought they could stretch it that far, you would be the one to try to do so. :rolleyes:

Roland Miller
02-11-2009, 11:39 AM
I was testing you to see if what you think you know is really what you know and how that applies to the real world. The real world does not exist in the books you protect your ego with...:eek: You failed..

Jerry Peck
02-11-2009, 01:35 PM
I was testing you to see if what you think you know is really what you know and how that applies to the real world. The real world does not exist in the books you protect your ego with...:eek: You failed..


In which case you failed as a "teacher" and "mentor" as you should be offering help, not distraction with nonsense.

By the way, your "real world" is "really addressed" in those code books you so passionately spout and refer to ... when it pleases you, and you so passionately despise when that pleases you.

Thus, the object here is not that it is your "real world", but that it is "your" real world, with a great and vast difference between the two.

Roland Miller
02-11-2009, 04:17 PM
You are a little fuzzy--but I understand you don't get it... Some mentor you are!!:rolleyes:

Jerry Peck
02-11-2009, 04:48 PM
You are a little fuzzy--but I understand you don't get it... Some mentor you are!!:rolleyes:

One can only be a mentor to one who wants to understand, ... not to someone who is so full of oneself that they totally block out what is being said and shown to them ... said and shown to them time and time again. :rolleyes:

Roland Miller
02-11-2009, 05:33 PM
Jerry--my probation officer is afraid I will have a relapse so I have you on ignore and will no longer respond to your nonsensical BS..

Jerry Peck
02-11-2009, 06:16 PM
Jerry--my probation officer is afraid I will have a relapse so I have you on ignore and will no longer respond to your nonsensical BS..

Excellent, that means you will not be spreading your BS and incorrect opinions around as though they were actually correct?

Cool! :cool: