Driving a seperate ground rod

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I think the electricial service in my house is adaquate, but I suspect that my copper pipe is not. Would it be legal to drive a seperate ground rod to bond the copper pipe in my basement? We were on a well at one time but now we have county water. The piping from the county to the house is pvc.
The reason I suspect the copper pipes is that during an electricial storm I lost a modem once. It would power up but the phone line part would not function. The incoming phone line is bonded to the copper pipe in the basement.
I now have two computers that I think the mobo's are dead. There was a storm before I came home. The computers are plugged into a surge suppressor and a UPS. The power supplys in the computers are good, but I strongly suspect that the mobo's are toast. I am afraid they took a hit from the Cat 5 coming from the modem. The cable is also grounded with the same copper pipe.
The sad thing is that the UPS does have protection for the Cat 5 cable, but during some trouble shooting I had done in the past the Cat 5 was not re-hooked to the UPS.
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It's not only legal, its required. Install the rod and connect the cable to the neutral -ground bar in your main service panel. Any copper internal piping should also be bonded to the grounding system

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Thanks.
Would it be legal to connect it to the neutral bar in a sub panel in the basement?

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No, the neutral bus should only be bonded to the ground in the Meter/Main Panel, not the Sub-panels.
The thing they started doing here (Sonoma County California) is to run 20' of #6 Copper solid wire mixed and inter-twined in the rebar of the foundation. then bring it up into the meter panel.
Scott<-

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No, it has to be the main panel

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Terry wrote:

When the water supply was changed to PVC you lost the system ground. I agree with RBM, you need at least 1 ground rod. Ground rods are not very good, but they are far better than what you have now - nothing.
Starting with the 2005 NEC, for most new buildings a concrete encased electrode - one version of which is described by Scott - is required.
Excellent formation on surges and surge protection is in an IEEE guide at: http://omegaps.com/Lightning%20Guide_FINALpublishedversion_May051.pdf And a simpler NIST guide at: http://www.nist.gov/public_affairs/practiceguides/surgesfnl.pdf
An important point is to have a "single point ground" - entrance protectors for CATV, phone, ... be connected with a *short* wire to the conductor to the earth electrode at the power panel. With a large surge there will always be a difference from the house ground to absolute ground. The goal is for the power and CATV and phone 'grounds' to rise together. Sometimes entry points are distant but a phone, ... wire can be run from its entry point to a 2nd protector adjacent to the power service and phone wires distributed from there. Or use a multiport plug-in suppressor. (For an illustration of the hazard see the IEEE guide pdf page 40.)
The NIST guide cites US insurance information that indicates equipment most likely to be damaged by lightning is computers with modem connection and TV related equipment - presumably with CATV connection. All can be damaged by surge voltage between signal and power, and a single point ground removes much of the risk.
That is also why signal wires must go through plug-in suppressors, as you indicated. All interconnected equipment must be connected to the same plug-in suppressor, or external wires must go through the suppressor. A plugin suppressor clamps the voltage on all wires (signal and power) to the common ground at the suppressor. Mulitport suppressors are described in both guides.
And the final protective device that can be used is a surge suppressor at the power service. They are also described in both guides.
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The MDP (main distribution panel) needs to be grounded with a ground rod to have 25 ohms resistance or less. In an updated system, subpanels cannot allow neutral and ground to terminate on the same bar or allow the neutral to bond to the panel, the neutral path and ground path are maintained separately. Here is a discussion: http://forums.mikeholt.com/archive/index.php/t-56380.html
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does the old water line to the well still exist? excellent ground connect it to the new ground rods for maximum safety and protection
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Does the code actually require that now?

This implies it still does not.
The old requirement was that if the first rod was over 25 ohms you had to put in a second rod. Testing resistance after that was not required even if/when it was still over 25 ohms. This is the source of the "drive two go home" stuff -- if you can't test, two rods will always, by definition, meet code.
sdb
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Thanks for every one's comments. Boy those typos were bad. :)
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Your post implies earthing to eliminate surge damage. Earthing must answer to many masters. For example, it is required by code for numerous human safety reasons. Any fault must trip a circuit breaker. Transformer neutral failure will not cause excessive currents via gas meter and resulting explosion. Etc.
Earthing for transistor protection means earthing also must exceed post 1990 code requirements. Code only addresses human safety which is why water pipe earthing is no longer sufficient and does not meet post 1990 code requirements. For transistor protection, that same earthing also must exceed code requirements.
Code says breaker box (with main disconnect) must be earthed (some jurisdictions want this earthing in the meter panel). For transistor protection, that earth must also be less than 10 feet, no sharp wire bends, no splices, everything earthed to one electrode, etc. Code does not demand any of this. But to eliminate motherboard surge damage, these are some additional requirements for earthing.
Still that is not sufficient. For example AC electric service has three wires. If any one wire is not earthed, then modem damage can result. But how is AC electric delivered when all three wires are earthed? Neutral wire must be earthed directly. But other 'hot wires' must make that 'less than 10 foot' connection via a protector.
Notice what a protector does. It does not (and does not claim) to provide protection. The protector is simply a connecting device to earth ground. Nothing more. A protector without that earth ground many even earth surges destructively via adjacent appliances (Page 42 Figure 8 in http://omegaps.com/Lightning%20Guide_FINALpublishedversion_May051.pdf ).
A protector that makes that 'less than 10 foot' earthing connection means 1) surges will not enter a building to seek earth ground destructively via modem and motherboards, 2) protection inside all other household appliances is not overwhelmed, and 3) everything in the building human safety appliances (ie smoke detectors, GFCIs) also are protected.
Earth ground is the protection. Protection improves when a single point earth ground is even made better (ie 'less than 10 foot connection). Most important - every incoming wire in every cable must connect 'less than 10 feet' to that earth ground before entering the building. Your telco does that so their switching computer connected to overhead wires all over town is never damaged. The technique is that effective and that well proven. Again, the protector is only a connecting device to protection. Better protection means better earthing.
Did you know the telco installs a 'whole house' protector on you phone line? Why? Because that protector is so effective and costs massively less compared to a plug-in protector. But again, if a protector does not make a connection to earthing, then the enter protection system is compromised. - like a water pipe replaced in PVC.
Cable TV does not need a protector. Why? Protectors do not provide protection. Cable is protected by a $2 ground block and a wire to the earthing electrode. Protectors would only diminish that protection - but enrich some manufacturers. What defines quality of that protection system? Earth ground. Better earthing means less surge will enter a building to overwhelm protection already inside all household appliances.
Above is the technology. If you learn the technology, then Bud's people don't profit by selling protectors without earthing. Page 42 Figure 8: TV damaged by 8000 volts because an expensive plug-in protector was too far from earth ground (basically had no earthing), plug-in protector was too close to appliance, AND earthing system violated principles cited above.
How to identify the ineffective protector? It has no dedicated wire to make that 'less than 10 foot' earthing connection AND manufacturer avoids all discussion about earthing. Therein defines where that ground rod must be located and how everything connects to it.
Do you run the ground wire from breaker box, up over foundation, and down to earth ground rod? Yes to meet code. Not sufficient to protect computers. The ground wire over foundation would have too many sharp bends, be too long, and would be bundled with other non- earthing wires. Ground wire bundled with other wires may even induce surges on those other wires. That ground wire must pass through foundation and down to earthing electrode. Wire must be shorter, less bends, separated, etc.
Concepts that define where an earthing rod is located and how connections are made are in comp.sys.mac.comm on 4 Jul 2007 entitled "DSL speed" at http://tinyurl.com/2gbgef
What happens when a plug-in protector has no dedicated earthing wire - cannot make that 'less than 10 foot' connection? Page 42 Figure 8 is one example: the surge finds another path to earth - 8000 volts destructively - via the adjacent TV. TV earthed a surge because it was not earthed where wire entered the building. No earth ground means no effective protection.
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It that a yes or no?
What I really want to know is if I am "required" to ground a copper piping system in my house for grounding for the CATV if the piping may be replaced with PVC?
If grounding is not "required" then I am going to ask the CATV to come out and bond their service to my electrical service mast.
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There is no requirement in the NEC to bond a piping system that does not extend at least 10 feet out into the ground. There are still many inspectors who might well say they would sure prefer seeing a ground clamp on the pipe. It is easier to just put one on.
CATV should share your MDP bonding, usually a ground rod (pretty normally two here - cheaper than having an engineer or test lab stamp to ensure 25 ohms or less)
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Thanks.
That is what I wanted to hear.

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Trouble is, it's wrong. See my response directly to DanG.

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Doug Miller (alphageek at milmac dot com)
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All water pipes are bonded to breaker box so that any electricity (a fault) in those pipes is removed. Number one reason for bonding to water pipes is to remove dangerous currents. Number one reason is not earthing.
Also, nothing must connect to water pipes to dump electricity into those pipes (called grounding). Every electrical connection to household pipes is to remove electricity (ie trip a breaker) so that wet humans never conduct electricity.
Homes *bond* (not ground) water pipes. volts500 provides a nice summary of pipe bonding in the newsgroup alt.home.repair entitled "Grounding Rod Info" on 12 July 2003 at http://tinyurl.com/hkjq
No longer acceptable is connecting cable to some water faucet. Cable ground as defined by NEC in article 800.33 must be made directly to NEC defined earthing electrodes in article 205.50. This is bonding and grounding for human safety. Then these requirements must be exceeded for transistor (modem) safety.
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DanG wrote:

Dan That is incorrect. Any interior metal water piping that is likely to become energized is required to be bonded to the the main bonding jumper at the service disconnecting means. Which piping is likely to become energized? That is up to the representative of the authority having jurisdiction to decide. That person is the local electrical inspector. Some inspectors will except that the Equipment Grounding Conductor (EGC) of the circuit that may be the source of the unwanted current is sufficient bonding. Others will want the bonding conductor sized to the size of the main breaker. -- Tom Horne
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FALSE.
"Metal water piping systems installed in or attached to a building or structure shall be bonded to the service equipment enclosure, the grounded conductor at the service, the grounding electrode conductor where of sufficient size, or to the one or more grounding electrods used." [2005 NEC, Article 250.104(A)(1)]
Nothing there about "at least 10 feet". Nothing there about it being in contact with the ground at all. Just "shall be bonded".
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Yes, you are. All metal water piping is required to be bonded to the electrical system ground. Period.
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Doug Miller (alphageek at milmac dot com)
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On Mon, 30 Jul 2007 12:07:42 GMT, snipped-for-privacy@milmac.com (Doug Miller) wrote:

Okie Dokie.
I am going to drive another ground rod and bond it where the panel is attached to the water line.
Thanks everyone.
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