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#1
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Where can I get an extra long grounding rod?
I'd like to add a quality grounding rod to my house. I know from prior research, that ground water exists from maybe 12
to 17 feet below ground, below which is hardpan. It seems that a 17 foot ground rod would give me the best ground, but 10 feet seems to the the longest I can find. Are there longer ground rods available? Where? Is my reasoning "reasonable"? bob |
#2
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Where can I get an extra long grounding rod?
wrote in message How would you drive in a rod that is 17 feet long? It's a bitch driving in a 10 footer at times. You got to get on a ladder and then the think likes to bounce around as you sledge hammer it down. 10ft. is plenty, and in most areas, the NEC requires at least 2 rods spaced at least 10 ft apart, then bonded together. It would make more sense to couple two rods somehow. Drive one in, put on the coupling, then the second rod. I imagine they don't make extra long ones because they are not needed, not practical. |
#3
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Where can I get an extra long grounding rod?
Utilities buy "screw-in" ground rods that are driven in with a
gas-powered tool and have a cast screw on the end that goes in the ground. Some of these can be "extended" to your desired 17 feet. But these rods are not cheap (hundreds of dollars) and the tools are exquisitely specialized. Unless you are having trouble getting the low-resistance-to-ground that the NEC requires (which might be the case if you live on the side of a mountain for example) such measures are usually not necessary. If you're as close to the water table as you claim then the two code-required 8 foot/10foot rods are probably pretty good for most purposes. Plain old water pipe can be driven down (and extended) more easily than ground rods to your desired 17-foot distance. Depending on what your inspector says you will probably need the two code-compliant (shorter) grounding electrodes too. |
#4
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Where can I get an extra long grounding rod?
Edwin Pawlowski wrote:
wrote in message How would you drive in a rod that is 17 feet long? It's a bitch driving in a 10 footer at times. You got to get on a ladder and then the think likes to bounce around as you sledge hammer it down. 10ft. is plenty, and in most areas, the NEC requires at least 2 rods spaced at least 10 ft apart, then bonded together. It would make more sense to couple two rods somehow. Drive one in, put on the coupling, then the second rod. I imagine they don't make extra long ones because they are not needed, not practical. They make sectional ground rods; the ends are threaded (including the pointy end), and thet have special couplers and a driving stud so you don't bugger the threads when you pound on them. But last time I checked, 3/4" (or larger) galvanized water pipe or RMC is NEC approved for use as a made electrode, and can be had in 20' lengths without needing a coupling. I would drive it using a ladder and a T-post driver rather than a sledgehammer. Best regards, Bob |
#5
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Where can I get an extra long grounding rod?
"Bob" wrote in message ... I'd like to add a quality grounding rod to my house. I know from prior research, that ground water exists from maybe 12 to 17 feet below ground, below which is hardpan. It seems that a 17 foot ground rod would give me the best ground, but 10 feet seems to the the longest I can find. Are there longer ground rods available? Where? Is my reasoning "reasonable"? bob google is your friend http://www.erico.com/products/copperbonded.asp quality grounding rod? I know of no study that has found that getting a ground rod into the water table is worth the effort. Sure would be hard for us folks in the SW deserts. Placement of the "supplemental ground rod" should be outside the sphere of the primary grounding system. Amec makes a meter that can measure ohms/volts to ground with out interruption. http://www.giscogeo.com/pages/grsae371.html My personal favorite. I measured my last house and found that the installed ufer ground was less than 10 ohms. Not much reason to spend the effort in setting another ground in that situation. That was done on a dry July morning. |
#6
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Where can I get an extra long grounding rod?
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#7
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Where can I get an extra long grounding rod?
"zxcvbob" wrote in message ... Edwin Pawlowski wrote: wrote in message How would you drive in a rod that is 17 feet long? It's a bitch driving in a 10 footer at times. You got to get on a ladder and then the think likes to bounce around as you sledge hammer it down. 10ft. is plenty, and in most areas, the NEC requires at least 2 rods spaced at least 10 ft apart, then bonded together. It would make more sense to couple two rods somehow. Drive one in, put on the coupling, then the second rod. I imagine they don't make extra long ones because they are not needed, not practical. They make sectional ground rods; the ends are threaded (including the pointy end), and thet have special couplers and a driving stud so you don't bugger the threads when you pound on them. But last time I checked, 3/4" (or larger) galvanized water pipe or RMC is NEC approved for use as a made electrode, and can be had in 20' lengths without needing a coupling. I would drive it using a ladder and a T-post driver rather than a sledgehammer. Thanks everyone. It sounds like the galvanized pipe solution will be the easiest solution for this problem. My soil is a fine sand below about 2 feet, so driving the rod should be no problem. I can push a "normal" rod down 4 or more feet by hand. Would it be fair to assume that if I combine multiple rods that they should all be galvanized if any one is? In other words, I shouldn'd mix galvanized and copper plated rods? Bob |
#9
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Where can I get an extra long grounding rod?
copper is pretty much incompatible with almost all common metals except
passivated stainless steel and lead. Iron and zinc are both prone to galvanic reactions when in contact with copper. In short - no don't mix copper plated with other types. |
#10
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Where can I get an extra long grounding rod?
In article .com,
says... Utilities buy "screw-in" ground rods that are driven in with a gas-powered tool and have a cast screw on the end that goes in the ground. Some of these can be "extended" to your desired 17 feet. But these rods are not cheap (hundreds of dollars) and the tools are exquisitely specialized. A threaded 3/4" grounding rod is around $25 for 10 feet, including the pointed end. Couplings are around $8. Not as beefy as what the utilities use, but how many amps do you plan to dump down a household ground rod? -- is Joshua Putnam http://www.phred.org/~josh/ Braze your own bicycle frames. See http://www.phred.org/~josh/build/build.html |
#11
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Where can I get an extra long grounding rod?
SQLit wrote:
"Bob" wrote in message ... I'd like to add a quality grounding rod to my house. I know from prior research, that ground water exists from maybe 12 to 17 feet below ground, below which is hardpan. It seems that a 17 foot ground rod would give me the best ground, but 10 feet seems to the the longest I can find. Are there longer ground rods available? Where? Is my reasoning "reasonable"? bob google is your friend http://www.erico.com/products/copperbonded.asp quality grounding rod? I know of no study that has found that getting a ground rod into the water table is worth the effort. Sure would be hard for us folks in the SW deserts. Placement of the "supplemental ground rod" should be outside the sphere of the primary grounding system. Amec makes a meter that can measure ohms/volts to ground with out interruption. http://www.giscogeo.com/pages/grsae371.html My personal favorite. I measured my last house and found that the installed ufer ground was less than 10 ohms. Not much reason to spend the effort in setting another ground in that situation. That was done on a dry July morning. From the picture and the text that device is only measuring current. Its somehow calculating resistance based on that - I cant imagine it being anywhere's near accurate. If it were that simple you could use your clampon ammeter and a table. Eric |
#12
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Where can I get an extra long grounding rod?
On Thu, 27 Oct 2005 10:33:55 -0700, Eric wrote:
SQLit wrote: "Bob" wrote in message ... I'd like to add a quality grounding rod to my house. I know from prior research, that ground water exists from maybe 12 to 17 feet below ground, below which is hardpan. It seems that a 17 foot ground rod would give me the best ground, but 10 feet seems to the the longest I can find. Are there longer ground rods available? Where? Is my reasoning "reasonable"? bob google is your friend http://www.erico.com/products/copperbonded.asp quality grounding rod? I know of no study that has found that getting a ground rod into the water table is worth the effort. Sure would be hard for us folks in the SW deserts. Placement of the "supplemental ground rod" should be outside the sphere of the primary grounding system. Amec makes a meter that can measure ohms/volts to ground with out interruption. http://www.giscogeo.com/pages/grsae371.html My personal favorite. I measured my last house and found that the installed ufer ground was less than 10 ohms. Not much reason to spend the effort in setting another ground in that situation. That was done on a dry July morning. From the picture and the text that device is only measuring current. Its somehow calculating resistance based on that - I cant imagine it being anywhere's near accurate. How do you suppose ohmmeters work? The caculation is done by the mechanism in mechanical meters, but all they do is measure amperage, which they do by measuring voltage drop. Everything is calculated from voltage drop, mechanically or electronically. If it were that simple you could use your clampon ammeter and a table. If your clampon is accurate. Eric Remove NOPSAM to email me. Please let me know if you have posted also. |
#13
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Where can I get an extra long grounding rod?
Eric wrote:
SQLit wrote: "Bob" wrote in message ... I'd like to add a quality grounding rod to my house. I know from prior research, that ground water exists from maybe 12 to 17 feet below ground, below which is hardpan. It seems that a 17 foot ground rod would give me the best ground, but 10 feet seems to the the longest I can find. Are there longer ground rods available? Where? Is my reasoning "reasonable"? bob google is your friend http://www.erico.com/products/copperbonded.asp quality grounding rod? I know of no study that has found that getting a ground rod into the water table is worth the effort. Sure would be hard for us folks in the SW deserts. Placement of the "supplemental ground rod" should be outside the sphere of the primary grounding system. Amec makes a meter that can measure ohms/volts to ground with out interruption. http://www.giscogeo.com/pages/grsae371.html My personal favorite. I measured my last house and found that the installed ufer ground was less than 10 ohms. Not much reason to spend the effort in setting another ground in that situation. That was done on a dry July morning. From the picture and the text that device is only measuring current. Its somehow calculating resistance based on that - I cant imagine it being anywhere's near accurate. If it were that simple you could use your clampon ammeter and a table. Eric Or a 5A fuse... Best regards, Bob |
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