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Posted By: Joe Tedesco Ground Rod Installation - 08/09/02 12:30 PM
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Using the 2002 NEC, What's wrong here?

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[This message has been edited by Joe Tedesco (edited 08-09-2002).]
Posted By: Redsy Re: Ground Rod Installation - 08/09/02 03:51 PM
250.53 (G)
Last sentence.
The upper end of the electrode shall be flush with or below ground level unless the aboveground end and the GEC attachment are are protected against physical damage.
BTW,
I would have the conductor on the other side of the rod, with the set screw biting into the rod itself.
Posted By: HotLine1 Re: Ground Rod Installation - 08/09/02 10:26 PM
I believe that the "acorn" clamp is used incorrectly. As Redsy said, the method we have always used is the rod is between the setscrew and the conductor. In the manner it's installed, physical damage will be inflicted on the conductor.

Also. the rod must be flush or below grade, or protected from physical damage.

HotLine1
John
Posted By: pauluk Re: Ground Rod Installation - 08/09/02 11:25 PM
We use similar style clamps in England.

I agree with you -- I always put the cable on the opposite side to the set screw.
Posted By: Gwz Re: Ground Rod Installation - 08/10/02 12:16 AM
Appears to me that the rod is cut about half-way-thru just below the acorn clamp losing circumference.
Posted By: Currently Re: Ground Rod Installation - 08/11/02 03:13 PM
That 'groove' is there so an inspector can tell if the entire rod is driven into the ground. Pulling these things out after hitting ledge or a stone is not a fun or productive thing to do. (Why does it happen at 6 1/2 feet?)

Wondering what are some techniques some of you guys use for driving them in or pulling them out?
Posted By: caselec Re: Ground Rod Installation - 08/11/02 06:25 PM
We us a Bosch Demo Hammer with a ground rod attachment. Works great and easy on the body.
Posted By: arseegee Re: Ground Rod Installation - 08/11/02 07:28 PM
I use a rotary hammer with rod attachment. Best money I ever spent. When I have to do it by hand I use a "monster maul". It's an over sized wood splitting maul that has a 32" hollow pipe handle and a 16 pound head. Just slide handle over rod and go.
Posted By: joeh20 Re: Ground Rod Installation - 08/13/02 09:06 AM
We put in 18 one day at a mobile home park we set up. Put 17 of them in with the front endloader bucket on a 40hp Kabota tractor.
Start them in a hole with a shovel and let the bucket down. One hit a rock and doubled back and came back out about two and half feet above grade. We replaced it with a new one drove with a Milwaukee demo hammer and ground rod attachment.
Posted By: Bjarney Re: Ground Rod Installation - 08/14/02 01:42 AM
I have found radically different soil conditions within ten miles...from mean hardpan to one that just about was lost in “quicksand”-like conditions. I’ll side with sparky the ¾-inch GRC is just right for ¾-inch rods. A ±3x18-inch shaft scrap can be welded to a ¾x6-inch GRC nipple, and three more nipples strung together with couplings. After reaching ~2-foot rod exposure, depending on elbow room, remove the nipples one at a time, or, reversing the driver and use the GRC attachment as a handle to limit stoop labor.
Posted By: kduke Re: Ground Rod Installation - 08/19/02 12:11 PM
Who pulls them out? It's cheaper to leave them in and drive another. To drive them down, ever use water? Plunge the rod up and down, like clearing the tiolet, adding water all the time. It's a poor man's roto-hammer.
Posted By: John Steinke Re: Ground Rod Installation - 08/27/02 01:23 AM
We do ground rods somewhat differently here.
First of all, we have to use a 10' rod. Since our ground has a lot of rock and hardpan, this means that about half the time it is necessary to bang in two rods (at least 6' apart) the 7-8' that they'll go.
Secondly, it's dry out here. The inspectors like to see the rods somewhat away from the wall, at the roof's drip line. Every bit of moiosture helps conductivity.
We are required to use #4 (1/4") solid wire
(or larger). The wire must be within EMT all the way to the ground rod.
Finally, the inspector likes to have the rod project out of the ground a few inches, so he can inspect the proof mark that identifies the rod (so a short rod isn't just cut off, then the saw marks banged up some).
I use a demolition hammer- slightly larger than a "roto hammer", but smaller than a "jack hammer." I also use a "post pounder-" a length of pipe with handles, and a good, heavy slug of steel at the end. (Good welding class project!)
Finally, a problem I've encountered with service changes is that old buildings frequently have footings about 5' down that project out some distance from the wall. Lots of luck with the ground rod if you hit them!
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