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Joined: Jan 2002
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Installing a service in an old barn today. Could not get the ground rods in. (bedrock?) Instead I laid them in the trench that the service is run in. It is about three feet deep. I used three rods, each one six feet from the other. Reading through the handbook I am not to clear on this exact situation. Appreciate all thoughts.
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Joined: Apr 2001
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Scott. According to 250.53(G) you've satisfied the NEC providing the trench you put them in was at least 30" deep. Sounds like you did the best anyone could do and then some.
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Joined: Feb 2003
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20' of #4 bare copper would be acceptable in the ditch too, if your AHJ has no problems with that.
Shoot first, apologize later.....maybe
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Joined: Nov 2000
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Zapped, Please cite the code section that permits the use of 20' of #4 in a ditch as a grounding electrode. Don
Don(resqcapt19)
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Joined: Jul 2002
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We do this sort of thing all the time in New Zealand, especially where a really good Earth is required, we lay out about 20-30 metres of 35-50mm2, for really poor soils and it works a treat. This sort of system is really only used for Earthing Distribution Transformers and the like, no one would like a bill for this sort of wire at these lengths.
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Joined: Feb 2003
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Don,- While there is no direct code section stating we can install the electrode system as I said, there also is no wording that says I cannot. Basicly we are using 250.52(A3&4) without the concrete. On our larger services we use 2,3,&4/0 copper. Our AHJ's have no problems with these installations. Don't get me wrong, I do use ground rods 90% of the time.
Shoot first, apologize later.....maybe
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Joined: Mar 2003
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Scott, what you did will satisfy code. Another option would have been to use a ground ring or plate electrode.
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Joined: Nov 2000
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zapped, There is wording that says you can't do that. The code lists the grounding electrodes that are permitted to be used in 250.52. Installing 20' of bare copper in a ditch is not on the list, unless the 20' encircles a building. I see no reason why it shouldn't be just as good as a ground ring, but it is not permitted by the NEC rules.
Don(resqcapt19)
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Joined: Feb 2003
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don :
i hate to ask you a stupid question but i know i will respect you with this one anyway but you mean that cant bury bare copper wire unless it is around the building that mean all the way around the building area ??? ( i never done this one so i am double checking i did see it on nec code say cant bury it in short straght section ..)
thanks for your time
merci marc
Pas de problme,il marche n'est-ce pas?"(No problem, it works doesn't it?)
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Joined: Feb 2003
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Don,- Maybe the CMP should take a closer look at 250.52(A4), kinda hard to take 20' of wire and encircle a 25+ 40' building.
Shoot first, apologize later.....maybe
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