Retrofit-Grounding Fifties-Era House?

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I tried this in misc.rural, and got a recommendation to try it here. ------------------------------------------------------------- Been quite awhile since I started wondering what it was with the "Building Wiring Fault" lights on my UPS'.
In doing some homework prior to getting a generator transfer switch installed, it became apparent that houses need tb "Grounded" - and the typical ground is one or more copper rods pounded into the ground and then attached to a (neutral?) wire in the breaker panel.
This house is a split-level, crawl space but no basement, built in the fifties and I am unable to find anything that even looks like a ground.
One reason for no ground might be what the house is built on: a shale ridge. The builder scooped a notch out of a hillside, sold the topsoil, and built this house on the notch. Go down about 4", and you hit shale that is so solid that you need an air hammer or a breaker bar and lots of time to get through - as in 3 days with a breaker bar and a tin cup to make 2 4" wide 28" deep holes for a boat rack I put in last year.
Realistically, we've been in this house for 30+ years and never lost an appliance to electrical surge... but still... there's got tb good reasons for grounding.
That being said, I'm exploring after-the-fact methods.
The obvious is the copper pipe that water comes in on: buried several feet deep and running a good 30' to the main under the street. Seems like this was SOP until some time in recent history when it was deemed inadequate.
The second thing that comes up is a "Ufer" ground wherein the ground wire is tied to rebar in the house's foundation. I can find a lot of articles on the techniques of doing this in new construction, but nothing about retrofits.
The third approach seems tb lateral: long trenches in the yard with the grounding medium layed in the trench. Seems impractical to me bc the standard calls for 30" deep...
Has anybody been here: retrofitting a ground system to a house built on shale or rock?
--
Pete Cresswell

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I would want an evaluation of the current hookup from the pole. Do you have a pole ?
Greg
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Per gregz:

Yes.
Could that be something the electric utility would be willing to do?
I'm thinking maybe some sort of equipment or even personnel safety concern.
--
Pete Cresswell

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Don't think. If it were here, I could ask local permit office for requirements. If things were changed, then power company should inspect before meter was attached.
Greg
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look for ground wire coming down side of pole.
there are hammer tools designed to install ground rods which are currently coper coated stell for strength
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Per bob haller:

I think I found it: 6mm solid copper coming out of the breaker box in two places. I was looking for that woven flexy stuff that appears in so many photos - and the patina made it look like an old telephone cable.
One runs through a wall, down behind a drain spout, and disappears into the garden soil next to the house.
The other runs along the ceiling, into the furnace room, and attaches to a cold water pipe.
I think I'll pursue gregZ's recommendation and find somebody who can tell me if the system is actually working (in light of the "Ground Fault" lights on various UPS'). Maybe the guy who installs the cutover switch...although I have learned the hard way that not just any electrician chosen at random is what I'd call a craftsman.... Competence I don't know enough to judge... but the appearance of some of their work makes me wonder -)
One thing I don't like is that the 6mm copper is bundled in with an RG6 TV cable and several Cat5 Ethernet cables on it's way to the water pipe. Unencumbered by any knowledge, I have to wonder if a high voltage spike grounding out along that copper might bleed over and fry whatever Ethernet or TV devices are on the ends of those cables. Or can I trust it to completely take the path of least resistance?
While looking for the elusive house ground, I noted that the TV antenna we had installed several years ago has a long ground wire, but no ground. The wire is just coiled up in the garden soil next to the house under the antenna. I guess Job#1 (after a call to the installer....) is to run that wire through the crawl space and mate it up with a cold water pipe. ??
--
Pete Cresswell

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Best to separate things as much as possible. all my incoming is all in one place, but the wire to the water ground is 35 feet away.

Antenna ground should be far away as possible from other things, including your house.
Greg
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Says who? Typically an antenna is installed on the roof of the house and the ground is run to the single point grounding system for the house. Where should they run it to? Afghanistan?
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On 11/17/2012 7:05 AM, snipped-for-privacy@optonline.net wrote:

I agree. There should also be a ground block where the coax enters the house. That allows the coax shield to be earthed. That connection, in particular, plus the ground wire from the TV antenna, should connect to the earthing system near the service panel. During a surge "event" (or a near lightning strike) the "ground" at the service panel may be thousands of volts different from 'absolute' earth potential. Much of the protection is that all wiring in the house - power/TV antenna/cable/phone/... - rises together. That requires a short wire from entry protectors to a common connection point on the earthing system. The distance from the service N-G bond to the common connection point also has to be short.
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Per bud--:

Is there a conflict there for a TV antenna mounted on the North end of the house with coax running down the North wall and entering the crawl space there - and a service panel on the opposite end of the house?
--
Pete Cresswell

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In that situation the technically correct thing to do would be to have another ground rod on the end of the house with the antenna and have that ground rod bonded to the ground rod at the main panel. However there are plenty of houses out there that just have the antenna ground on one end and the panel grounded on the other. This common ground is one reason utilities, ie electric, phone, cable, etc come in at the same place.
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Per snipped-for-privacy@optonline.net:

Given that one of the building's grounds is a cold water pipe, it sounds like attaching that antenna ground wire to the nearest cold water pipe would do the trick.
Or would I be trying to electrocute anybody who happened tb using a faucet at the time of the strike?
--
Pete Cresswell

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Here are my concerns with that approach. You have an antenna mast up on the roof with a ground wire that leads back into the house and is connected to a cold water pipe. Lightning hits the antenna and where are you asking it to go? Into the house. Don't know about you, but I'd prefer to keep it out of the house. And the longer the path from the antenna to earth ground, the higher the impedance. Also adding to the impedance are any turns the ground wire and piping make on their way through the house. If you have a couple 90 deg, sharp turns where the ground enters the house on it's way to the water pipe, there is the distinct possibility that the lightning will decide there is an easier path to ground and go that route. For example, it could just arc over to earth near where it enters the house. Again, I'm sure you can find plenty of houses where this has been done with no ill effects.
An interesting alternate method would be to have a ground rod for the antenna and then use the cold water pipe to bond it to the main grounding system of the house. That way with a strike, the vast majority of the energy is going to go right to earth, not into the house. By having that ground rod bonded to the other system via the cold water pipe, it would keep the ground voltage level close, ie the two will be at somewhat similar levels. Without it, you could have the ground reference at the antenna point thousands of volts different from the main house ground. And then the TV for example, could get damaged.
But I don't know if it's kosher to use the cold water system to do the bonding. I could sleep OK if it were my house, but technically I suspect something in the code says you have to run an actual grounding conductor between the two ground rods. Perhaps Bud can weigh in on this.
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Per snipped-for-privacy@optonline.net:

Sounds to me like there is no downside to a dedicated grounding rod for the antenna - right under it where the ground wire drops down the side of the house.... and then work out the bonding possibilities with the rest of the ground system later.
Have I got it right?
--
Pete Cresswell

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The only downside is that later in many cases never happens. And until it is bonded to the house grounding system, with a lightning strike, you could have that ground and anything connected to it, ie TV, at possibly thousands of volts higher than the house ground, thereby destroying the TV, etc.
However, there are undoubtly a whole lot of houses out there where it's done with just the antenna grounded and no bonding. And given how much of a PIA it might be to run a proper bond, I might not do it myself either. At the end of the day, with what you describe, you don't have the perfect situation, but you do have a ground for the antenna and IMO it's not a big safety issue. More of an issue that the TV has a higher possibility of getting zapped.
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Per snipped-for-privacy@optonline.net:

But no higher than now with no ground rod at all, right?
Your observation about bonding later never happening rings true...
--
Pete Cresswell

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On 11/22/12 1:04 PM, (PeteCresswell) wrote:

temporary.
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Yes, I would think the possiblility of the TV getting zapped would be lower, not higher. If it were me, I would rather have the antenna grounded to a seperate ground rod that is not bonded to the main house ground, rather than no ground at all. At least you have a path for the main lightning current to follow and it's not into the house. In addition to the mast being grounded, there should be a lightning arrestor installed on the signal cable.

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On 11/22/2012 9:01 AM, (PeteCresswell) wrote:

The downside is that for a near strike, or strong surge current earthed through the power earthing system, the rod can be thousands of volts different from the building "ground". Those thousands of volts can show up at anything connected to the antenna and power. I wouldn't add a ground rod without bonding it back to the electrical system. But bonding does NOT eliminate this problem, created by the distant rod. IMHO the rod increases the probability of damage.
What the NEC wants now is the power system earthing connection to the water pipe within 5 ft of where the water pipe enters the house. One of the places for the rod bond to connect is in the same 5 ft. Years ago the power system connection could be anywhere on the water pipe. My preference generally is to connect the rod bond near the power service.
If lightning strikes the antenna, a ground rod will help only a little. The earth potential at the ground rod will likely be many tens of thousands of volts different from the building earthing and the building "ground". The antenna will be even further. There will likely be major damage. That can include arcing from the antenna or antenna wires to elsewhere in or on the house.
Ask a ham with a high antenna what you have to do for lightning protection. Earthing is only part of the protection. A major element is that all wiring rises to the same potential during a strike. You can't reliably do that with the distant (but bonded) rod. A start would be to route the antenna wire into the house adjacent to the power entrance with the antenna in a compatible location.
For most of us, it is real unlikely our houses (or antennas that don't stick way above the house) will be hit by lightning, and is not cost-effective to provide lighting protection.
Some principles: I isn't easy to make connection to the earth. A ground rod is one of the worst ways.
Two points of earth that are pretty close together can be many thousands of volts different during an "event".
The ends of a wire, maybe 20 ft long, can be thousands of volts different during an "event".
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On 11/20/2012 3:08 PM, snipped-for-privacy@optonline.net wrote:

I agree again.
The NEC wants a 20 ft max ground wire from the coax entry ground block to the power earthing system. If the wire is over 20 ft the NEC wants a ground rod near the coax entry point (connected to the entry ground block) and a #6 min bond wire from that ground rod to the power earthing system.
During an "event" that rod can be thousands of volts different from the building 'ground'. Because of the inductance of the bond wire and relatively high frequency current components of a surge, the bond wire does not necessarily reduce the voltage to a reasonable level.
IMHO the 20 ft limit is more reasonable for cable, where you have significant risk of surge entry. There should be little surge risk from a TV antenna. (The protection in the NEC is not for a direct lightning strike to the antenna - far more elaborate protection would be required.)
1 I might use a ground wire somewhat longer than 20 ft
2 If a rod is added at the cable entry you could run the coax near the power service and add a second ground block. (That adds coax length and signal loss.)
3 Just add a rod and bond wire.
Particularly for 1 and 3 (or leaving it the way it is) a plug-in protector at the TV would add protection. The coax must run through the protector. (All external wires go through the protector, and all interconnected equipment connects to the same protector.)
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