Single Grounding Electrode

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I have a question here - We recently did a service change from 200amp OH to 400amp UG and the question on the size of the GEC came up as to what we use - the house is a well, plastic pipe, and has no rebar sticking out of the concrete, so we installed ground rods. Is it safe to assume that in this case all we had to do was install a #6 copper to the ground rods, and a bond the water pipe correct? You also wouldn't need to use larger then #6 copper for the bond wire to the copper pipes either, would you? We were unclear of this, and happened to run 1/0 copper from the panels to the groundrods since I think we figured that table 250.66 needed to be used anywhere, but now as I read it, it seems that there were exceptions to it, such as for the rod not needing to be larger then #6...
 
badabing said:
I have a question here - We recently did a service change from 200amp OH to 400amp UG and the question on the size of the GEC came up as to what we use - the house is a well, plastic pipe, and has no rebar sticking out of the concrete, so we installed ground rods. Is it safe to assume that in this case all we had to do was install a #6 copper to the ground rods, and a bond the water pipe correct? You also wouldn't need to use larger then #6 copper for the bond wire to the copper pipes either, would you? We were unclear of this, and happened to run 1/0 copper from the panels to the groundrods since I think we figured that table 250.66 needed to be used anywhere, but now as I read it, it seems that there were exceptions to it, such as for the rod not needing to be larger then #6...
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To correctly bond the water check out 250.104(A)(1), As far as the ground rods check out 250.66 (A)
 
badabing said:
For which part, the ground rods or water pipeing?
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The ground rod only needs #6 but the water pipe should be bonded using Table 250.66.

Edit to add:
If you use parallel conductors, ie 2/0 copper for a residence. Then go to Table 8 in Chapter 9 and look up the cir mil for 2/0 and double it. Then check what size wire that would be and go to table 250.66
 
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badabing said:
I have a question here - We recently did a service change from 200amp OH to 400amp UG and the question on the size of the GEC came up as to what we use - the house is a well, plastic pipe, and has no rebar sticking out of the concrete, so we installed ground rods. Is it safe to assume that in this case all we had to do was install a #6 copper to the ground rods, and a bond the water pipe correct?
Click to expand...


Correct so far...


badabing said:
You also wouldn't need to use larger then #6 copper for the bond wire to the copper pipes either, would you?
Click to expand...

Not correct, see 250.104(A)(1)

badabing said:
We were unclear of this, and happened to run 1/0 copper from the panels to the groundrods since I think we figured that table 250.66 needed to be used anywhere, but now as I read it, it seems that there were exceptions to it, such as for the rod not needing to be larger then #6...
Click to expand...

Read 250.66(A) for Connections to Rod, Pipe, or Plate Electrodes.
 
gndrod said:
Well e/m, It might not be moot if the incoming water supply uses plastic pipe. Then the UFER is required prior to foundation pour unless the local authority says otherwise. The question arises, what water pipe is going to be installed, copper or pex?
I would not wait to find out, its cheaper and easier to stub up from a wire tied footer rebar rather than get blind-sided with being required to furnish two grounding rods, clamps, and extra lengths of copper GEC awg. rbj
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Not to mention too, that the CEE makes a heck of a lot better ground than the ground rods, even when you put in two of them in series. e/m.
 
Energy-Miser said:
Not to mention too, that the CEE makes a heck of a lot better ground than the ground rods, even when you put in two of them in series. e/m.
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The ground rods are in parallel.
Some where there is a document that states "the paralleling efficiency of ground rods can be improved by installing them twice the lenght apart".
I think its the IEEE green book.
Series would be end to end
 
The problem around here is that the footer is already poured before you ever see or bid on the job in most cases. There is no way to know whether or not you have a uffer to ground to. How does this affect the effectiveness of the grounding electrode?
 
tom baker said:
The ground rods are in parallel.
Some where there is a document that states "the paralleling efficiency of ground rods can be improved by installing them twice the lenght apart".
I think its the IEEE green book.
Series would be end to end
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Well, we are not talking about a circuit element here with two terminals (like resistors or capacitors for example), so I was using the word series loosely and not in the "network theory" sense. The tops of the ground rods are connected to the same unbroken lenght of bare is what the arrangement should be, regardless of the terminology.
e/m.
 
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