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Discussion Starter · #1 ·
I am wireing a small shed with 120/240/ 30 amp. and was installing the ground rod last night.

Well, I still have 18" above the ground that does not want to move.
Would you add another rod, and cut the first one short and connect them together, or abandon the first and connect to the second one?
Or does anyone have a super slick way to get that last 18" into the ground?
 

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Ax grinder
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You must have 8' of length of the ground rod in contact with the earth, see 250.53(G), so cutting off 18" would not meet this requirement unless the ground rod was a 10' rod.

Also, did the ground rod meet the 25 Ohm requirement of 250.56? If not you need a second rod anyway.

Chris
 

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You must have 8' of length of the ground rod in contact with the earth, see 250.53(G), so cutting off 18" would not meet this requirement unless the ground rod was a 10' rod.

Also, did the ground rod meet the 25 Ohm requirement of 250.56? If not you need a second rod anyway.

Chris

He did say cut that one and add another, not cut it and use it.
 

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If you think a second one will be tough to drive in put it at a sharp angle.
Not sure if it's the POCO here or an NEC requirement, don't have my book on hand :whistling2:. If the ground rod is put at an angle it has to be 45 - 90 degrees.

Also, did the ground rod meet the 25 Ohm requirement of 250.56? If not you need a second rod anyway.
Chris
Funny that you say that Raider. Got a call from a client who told me to call the POCO about her meter. Ends up that the meter they are putting on won't work since the ground system doesn't meet the 25 Ohm requirement. It's an 80 year old house so I'll be sinking a couple rods there this Friday.
 

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Did you try the cup of water trick? Also whats the code on laying it down in a ditch I seen people do it before and say it was ok but i was skeptical.
 

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Ax grinder
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Did you try the cup of water trick? Also whats the code on laying it down in a ditch I seen people do it before and say it was ok but i was skeptical.
Here is what the 2008 NEC says about installing ground rods:

250.53(G) Rod and Pipe Electrodes. The electrode shall be installed such that at least 2.44 m (8 ft) of length is in contact with the soil. It shall be driven to a depth of not less than 2.44 m (8 ft) except that, where rock bottom is encountered, the electrode shall be driven at an oblique angle not to exceed 45 degrees from the vertical or, where rock bottom is encountered at an angle up to 45 degrees, the electrode shall be permitted to be buried in a trench that is at least 750 mm (30 in.) deep. The upper end of the electrode shall be flush with or below ground level unless the aboveground end and the grounding electrode conductor attachment are protected against physical damage as specified in 250.10.

Chris
 

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Ax grinder
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Funny that you say that Raider. Got a call from a client who told me to call the POCO about her meter. Ends up that the meter they are putting on won't work since the ground system doesn't meet the 25 Ohm requirement. It's an 80 year old house so I'll be sinking a couple rods there this Friday.
Thats interesting, what happens if you install a second rod and you still don't get 25 Ohms?

Chris
 

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Funny that you say that Raider. Got a call from a client who told me to call the POCO about her meter. Ends up that the meter they are putting on won't work since the ground system doesn't meet the 25 Ohm requirement. It's an 80 year old house so I'll be sinking a couple rods there this Friday.
What kind of meter requires a connection to earth to function?
 

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Discussion Starter · #17 ·
I always try to use a hammer drill with a ground rod bit.

Chris
That is what I am using, and of course the good old sledge hammer.

What is the cup of water trick?

I guess I'm driving another tomorrow.
 

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And what does the earth accomplish? sounds fishy if you ask me...
No idea, POCO is meeting me up there to put the meter on after I get the ground rods driven. He hasn't said anything about having to replace the meterbase, hopefully I don't need to.

I'll get some information from him about it.
 

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Thats interesting, what happens if you install a second rod and you still don't get 25 Ohms?

Chris
Nothing, you have satisfied the Code requirements. The Code does not require that you continue to drive additional rods until you get to 25 ohms or less.
 
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