Re: NEC Multiple electrodes
I think you need to go back one step further, to 250.53(D). The path of the engineer?s reasoning might have gone along the following lines:
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- <font size="2" face="Verdana, Helvetica, sans-serif">250.53(D): If I use a pipe, then I must supplement it with another electrode.</font>
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- <font size="2" face="Verdana, Helvetica, sans-serif">I choose to use a rod as the other (supplemental) electrode.</font>
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- <font size="2" face="Verdana, Helvetica, sans-serif">250.53(D)(2): Since I chose a rod, it must comply with 250.56.</font>
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- <font size="2" face="Verdana, Helvetica, sans-serif">Although 250.56 starts out by talking about a single electrode, I was sent to this section by the earlier statement that says that the ground rod has to comply with 250.56. That tells me that it has to meet the 25 ohm rule, without regard to the fact that is only a supplemental to the pipe. If it fails to make 25 ohms, then I need to ?augment? it with still another electrode.</font>
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- <font size="2" face="Verdana, Helvetica, sans-serif">I choose to use a second rod as the other (augmented) electrode.</font>
<font size="2" face="Verdana, Helvetica, sans-serif">I agree with the engineer.