Driving a seperate ground rod

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Also make arrangements to have other utilities grounded to that new earth ground or make a buried interconnection so that all other utilities share the same earth ground (as demonstrated a utility in http://www.cinergy.com/surge/ttip08.htm ). Code recommends that all incoming utilities use the same earthing electrode. But we do it for an even more important reason - surge protection.
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Terry wrote:

I'm not sure what you gain with another rod at that point. If I was adding rods I would add to the system at the electric service. The water pipe has to be bonded - a wire connection to the grounding electrode system for the power.
I don't remember what you said about the well. If you have an accessible pipe that attaches to the well casing, adding that to your grounding electrode system would be a good idea. (Or connect directly to the casing - but I remember you are not fond of the access.)
-- bud--
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wrote:

I didn't want to get into it because I don't type very well, but since you asked........
After tracking down my water piping I found that the electrical service is being bonded at a point where the well piping enters the house. The pump is located under the house. The piping for the well is some kind of rubber tubing. It looks like the house was never properly grounded. I hope there is another grounding point somewhere, but I don't see any signs of it.
The electrical panel has 1 number 6 leaving the panel at the top. I can only assume it goes over a door and then into the crawlspace.
Here is a sketch of what I have found.
http://i12.tinypic.com/53a88pe.jpg
Blue=panel green=#6 copper yellow=water pipe red=pit
Because the house has a partial basement, the pit is 8 ft deep under the house which makes it the most practical place to drive a ground rod.
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6 AWG wire to water pipe 'bonds' water pipe - to remove fault current (electricity) from water pipes. Code requires an electrode for earthing (even if water pipe did have buried conductive pipe). Code also says that earthing connection (for human safety) must be less than 20 feet. Code also wants telephone protector, cable TV coax, etc bonded 'less than 20 feet' to that new electrode.
Better is an electrode that grounds without sharp bends, 'less than 10 feet', that is easily connected to cable and telephone service, that uses a wire separated from all other wires, and can be inspected. Some may drill a hole and drive that electrode through concrete floor to exceed code requirements. How far away is that pit? More than 20 feet? Too far - would not be code acceptable.
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w_tom wrote:

If the water service pipe is 10 foot or more buried metal it is *required* to be used as an *earthing electrode*. A *supplemental* electrode is required because water pipe may be replaced with plastic in the future.
The size of the wire to a water pipe electrode is determined by the size of the electrical service conductors. #6 is too small for residential services of 200A. #6 wire must be "free from exposure to physical damage". #4 must be "protected where exposed to physical damage". #4 is often used instead of #6.

The NEC has no requirement for length from power system to earthing electrode.

New electrode?
The NEC required bonding is to anywhere on the electrode *system*.
For 1 and 2 family dwellings, the wire from phone NID to power earthing electrode *system* can be over 20 feet, but a ground rod must be add at the phone NID. The bond wire from phone ground rod to power electrode system must be at least #6. If less than 20 feet the wire only has to be #14.
20 feet is too long to provide a single point ground.

-- bud--
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Sometimes the well casing provides earthing. A closer inspection is required. What is that wire actually attached to and how is that connection accomplished? Device that bonds 6 AWG wire must be 'listed' to make that connection. 6 AWG wire would connect to interior copper pipe and to well casing. If so, both connections must use a 'listed' connecting devices as indicated by a marking on that connecting device.
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This seems to assume that the surge damage was in the supply lines. I don't think this is how I took a hit.
I believe the surge came "from" the CATV during the storm. The power supplies in the computers are good.
The damage was the modem, router, and motherboards.
Thanks for your time
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NEC says cable must be earthed. Why would a surge that seeks earth ground ignore that cable ground to enter your house and damage electronics - then continue on to another ground?
Every incoming utility must be connected to earth where wire enters the building. That is code required. Water pipe is no longer considered sufficient. Install a dedicated earthing electrode (from the NEC list in article 250.52). Water pipe is no longer sufficient for earthing. Post 1990 code now says any other earthing electrode must be installed. See article 250.52(D)(2) entitled "Supplemental Electrode Required". That electode can be located so that every earthing connection is 'less than 10 feet', etc.
Your posts imply thinking of surges like waves on a beach. Electicity does not work that way. Did a surge enter on cable, damage modem, then stop? Of course not. Where is the outgoing path from modem to earth. No outgoing path means no electricity entered on incoming path. First current must be flowing to earth. Long later is a modem damaged. If surge was incoming on cable, then where is the outgoing path? No current first flowing out to ground? Then no damage..
Damage on cable side of a modem can easily be incoming on AC mains - outgoing via that cable. Surge passes through other things while not damaging those others. Damage would be only at a weakest point. Why would a surge ignore cable earthing, damage a modem, then continue out of modem (how?) to earth ground? Earthed cable is typically an outgoing path. AC electric is most often the incoming path to damage cable side or phone side of modems.
How modems were so often damaged: Surge on black 'hot' wire is shunted to green safety ground wire. Now that surge connects directly to motherboard and modem - completely bypasses power supply. Through modem's off hook relay (destroying off hook relay's PNP transistor) and out to earth via 'telco installed' protector. Just another example of AC line surge that passes through everything but only damages something.
Repaired many modems by only replacing that one transistor. Modem worked fine for years even though other parts also conducted the surge. Only a weakest point was damaged.
Wires highest on utility poll are most often struck; most often a source of incoming surges. Next question - how did that surge seek earth ground? Best destructive paths to earth will only be via some appliances. Things you have assumed not conductive (power supply or linoleum floor tile) are possible conductors. Again, not like waves striking a beach. First current is flowing through sky, appliance, and earth simultaneously. Later something in the appliance fails. To protect, first identify all possible incoming paths - circuits that lightning would use to obtain earth ground via appliances because that wire was not properly earthed. Surge must be earthed before it can enter a building.
Critical earthing requirements include a 'less than 10 foot' connection and the electrode must be single point. Violate the requirements and lightning may seek other destructive paths to earth.
One utility demonstrates how to create a 'single point' when all utilities foolishly enter at mutliple locations. Single point ground is that buried interconnecting wire; http://www.cinergy.com/surge/ttip08.htm
Step back. Surge protection is not about the appliance. Protection must be viewed in terms of the entire properly. Effective protection 'systems' (so that protection already inside the appliance is not overwhelmed) is a complete building 'solution'.
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w_tom wrote:

w_ has a religious belief (immune from challenge) that surge protection must use earthing. Thus in his view plug-in suppressors (which are not well earthed) can not possibly work. The IEEE guide explains plug-in suppressors work by CLAMPING the voltage on all wires (signal and power) to the common ground at the suppressor. Plug-in suppressors do not work primarily by earthing. The guide explains earthing occurs elsewhere. (Read the guide starting pdf page 40).

The illustration in the IEEE guide has a surge coming in on a CATV drop. There are 2 TVs, one is on a plug-in suppressor. The plug-in suppressor protects TV1 connected to it.
Without the plug-in suppressor, the surge voltage at TV2 is 10,000V. With the suppressor at TV1 the voltage at TV2 is 8,000V. It is simply a *lie* that the plug-in suppressor at TV1 in any way contributes to the damage at TV2.
The point of the illustration for the IEEE, and anyone who can think, is "to protect TV2, a second multiport protector located at TV2 is required."
w_ says suppressors must only be at the service panel. In this example a service panel suppressor would provide absolutely *NO* protection. The problem is the wire connecting the CATV entry block to the power service is too long (not a "single point ground"). The IEEE guide says in that case "the only effective way of protecting the equipment is to use a multiport protector."

Needs no protector? The IEEE guide notes that the voltage between cable center conductor and sheath is limited by the breakdown of F-connectors which is typically 2-4,000V. The guide notes that connected equipment can be damaged at those voltages. Plug-in suppressors are likely to clamp the voltage to a reasonable level.

To quote w_ "It is an old political trick. When facts cannot be challenged technically, then attack the messenger." My only association with surge protectors is I have some.
It seems w_ must discredit those that do not agree with his bizarre ideas.

The lie repeated.

And read the responses.

And the lie again.

And the required statement of religious belief in earthing.
The question is not earthing - everyone believes in it. The question is whether plug-in suppressors are effective. The both the IEEE and NIST guides says they are.
w_ has never found a link that says plug-in suppressors are NOT effective. He just twists sources, like the IEEE guide to say the opposite of what they actually say. Read the source.
And w_ has never explained why the only 2 examples of suppression, at the end if the IEEE guide, use plug-in suppressors.
--------------- If there is not 10 foot underground metal water service pipe (water pipe not used as a grounding electrode), the interior metal water pipe is still required to be bonded by 250.104-A.
-- bud--
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