Does anybody ever oversize Grounding Electrode Conductors for long runs?

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Informational Note No. 1: An important consideration for limit‐
romex jockey said:
ing the imposed voltage is the routing of bonding and ground‐
ing electrode conductors so that they are not any longer than
necessary to complete the connection without disturbing the
permanent parts of the installation and so that unnecessary
bends and loops are avoided.

basic theory , but no math.....
:rolleyes:
~RJ~
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Agreed. Just meant it has been considered.
 
I would rather not have that bare #4 traveling the length of my house through the attic to get to the service equipment location. Just sayin’.
 
If it measures less than 25 ohms is there any reason to even have the discussion?

I guess maybe the added concern of "unnecessary bends and loops". Which in this particular project it's a bit of a zig-zag route.


Would it be silly to add ground rods even though they are not required in this scenario?

Rob G
 
marmathsen said:
If it measures less than 25 ohms is there any reason to even have the discussion?

I guess maybe the added concern of "unnecessary bends and loops". Which in this particular project it's a bit of a zig-zag route.


Would it be silly to add ground rods even though they are not required in this scenario?

Rob G
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What is it? Additional ground rods won't hurt but they probably won't do much anyway.
 
marmathsen said:
I was referring to the Ufer electrode and the ~125 of 4AWG Cu wire used to connect it from the original post.

Rob G
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Got it, that's what I thought but didn't want to guess. If any electrode were going to be 25Ω or less it would probably be the CEE which is probably the reason that measuring the CEE resistance is not required by the NEC.
 
marmathsen said:
If it measures less than 25 ohms is there any reason to even have the discussion?
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@ 1/2 million volts , it just might....


infinity said:
Got it, that's what I thought but didn't want to guess. If any electrode were going to be 25Ω or less it would probably be the CEE which is probably the reason that measuring the CEE resistance is not required by the NEC.
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25 ohms or less is required by many states infinity

~RJ~
 
romex jockey said:
i see, so just do what you're told, and forget electrical theory then Hv?



~RJ~
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Let's not forget electrical theory, let's talk about it.
romex jockey said:
Lightning and/or a primary event that manifests on the secondary are mitigated via mass and proximity.

Herbert Ufer's philosophy only took the nec 60 years to come to fruition , while denying 'earth' is a conductor, but insisting an R factor be present (25ohms<)

Lightning , or any heavy charge of caliber, also seeks straighter lines , farmers knew this before franklin :cool:

Is there a 780 guy in the house?

~RJ~
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The point you are trying to make would be easier to understand if what you said made any sense.
 
romex jockey said:
i often wonder how that # was arrived at


~RJ~
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I have heard many stories regarding the number from the Edison system, SWER systems, etc.
The most plausible seems to be 25 ohms should be reasonable to obtain about anywhere in the country without putting undue hardship on the contractor or homeowner to obtain these results.
this number goes all the way back to the 1915 or 1918 NEC code book I believe. (I could be wrong on the year)

Heres an article exploring the importance of grounding electrode resistance.
 
Hv&Lv said:
I have heard many stories regarding the number from the Edison system, SWER systems, etc.
The most plausible seems to be 25 ohms should be reasonable to obtain about anywhere in the country without putting undue hardship on the contractor or homeowner to obtain these results.
this number goes all the way back to the 1915 or 1918 NEC code book I believe. (I could be wrong on the year)

Heres an article exploring the importance of grounding electrode resistance.
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What's the lesson here?

Good one, but the real 'lesson' is here HV>>>


imagine if we actually achieved 25 ohms or less!

~RJ~
 
ActionDave said:
Let's not forget electrical theory, let's talk about it.

The point you are trying to make would be easier to understand if what you said made any sense.
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well first off, i'm assuming you know what a GEC is for Dave, 2ndly i'm assuming you know who Herbert Ufer is and the simple (Ohms law) theory behind his legacy

Further, the NEC has long been moot on earth ~R~. Does this not change due to moisture or PH ?

Last, if this was 1721, you'd be planting certain trees to either attract or repel lightning around your homestead / farm , folklore i know.... but then i also know more than one hunter who'll seek beech / birch in a sudden storm

~RJ~
 
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