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Old 02-11-2012, 11:52 AM   #31
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Multiple Ground Rods, help


Quote:
Originally Posted by Yoyizit View Post
Still, I'd think that the underground part would act like a distributed resistance and distributed capacitance and so somewhat lessen the effect of a lightning strike.
Yoyizit, with due respect I think you're completely misguided! It goes against my understanding and everything I've ever read.

You can look for more authoratative sources but this site sums it up: "When lightning strikes near a power line, whether it's underground, in a building or running along poles, the electrical energy can boost electrical pressure by millions of volts..."

Otherwise, you can read about specific lightning surges from the NOAA site.

I gain nothing by having some of my utility ran underground other than it looks better cosmetically...


Take care....


Last edited by Ralph III; 02-11-2012 at 11:57 AM.
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Old 02-12-2012, 10:59 AM   #32
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I think you are solving a problem that doesn't exist.
I COMPLETELY agree.
Considering the existing circumstances, ANYTHING done here is for the OP's peace of mind, not really much more than that.
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Old 02-12-2012, 12:56 PM   #33
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Multiple Ground Rods, help


Quote:
Originally Posted by Ralph III View Post

2) A whole house surge protector will be useless if not installed properly or grounded adequately. All insurance claims will be denied minus such.
And what purpose do you think sticking a piece of metal rod in the dirt is going to do?
"All claims"?? Got any documentation to back that up? I think your insurance claim comment is more scare tactics than anything.




Quote:
Originally Posted by Ralph III View Post
I'd rather protect my family and assets by installing a second $25.00 ground rod, as required in many states to insure adequacy, then sit around and post hypothesis as to other's unknown situations!
Again, what purpose do you think sticking a piece of metal rod in the dirt is going to do?

Even though they help with nearby strikes, even a hundred ground rods will not suppress a bad enough lightning strike.
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Old 02-12-2012, 01:34 PM   #34
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Well whole home surge won't hurt but it might not help. Sure extra ground rods won't hurt but they may not help either.

There is a problem with surges for devices which cross connect two or more utilities. Power and phone lines (including xDSL), cable and power, cable and power and phone.

The phenomenon is due to differential ground bounce. The principal defence against this problem isn't more ground rods but a very high integrity bonding of the utilities coming into the home at the entrance point. This way they are assured to not drift (called common mode) much relative to each other.

The building inspectors usually just check NEC grounding requirements for the electrical panel. You should check to see if the phone/Internet, and cable company bonded to that same point with a suitable gauge wire. If you have satellite the same goes. Bond to this common point.

Lets just agree to disagree on the underground vs overhead. To say they have equal vulernabilities is just misleading.
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Old 02-12-2012, 01:41 PM   #35
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Multiple Ground Rods, help


This is actually refreshing in a strange sort of way. Someone worrying more about ground rods than the End Of Civilization.
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Old 02-12-2012, 01:57 PM   #36
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Quote:
Speedy Petey; "And what purpose do you think sticking a piece of metal rod in the dirt is going to do?
"All claims"?? Got any documentation to back that up? I think your insurance claim comment is more scare tactics than anything".
You can read the documentation of surge equipment in regards to "warranty" or "guarantee" yourself. It clearly states how the equipment must be installed and by whom it is installed by. Otherwise, you're welcome to contact Denise Behers and/or Stephen Ploszay of Siemens Industry, Inc. Those are the people I've been consulting with in regards....

In addition, Insurance companies themselves can deny a claim if there is an improperly installed breaker, otherwise non-compatible, as members here have noted themselves.

If you want to put that notion to a test then do so at your own risk.

Quote:

Speedy Petey; "Again, what purpose do you think sticking a piece of metal rod in the dirt is going to do?

Even though they help with nearby strikes, even a hundred ground rods will not suppress a bad enough lightning strike."
You just completely contradicted yourself and single handedly destroyed your last point, when you stated, "ANYTHING done here is for the OP's peace of mind, not really much more than that".

Now you state, "Even though they help with nearby strikes....."

My whole thread was in regards to implementing a system by which spikes/surges could be limited. Where did I ever state anything about making my house immune from ALL surges, such as lightning strikes? That's not possible and I fully understand that.

However, we have personally sustained several surges large enough to damage printers, tv's, alarm equipment and alarm wiring. To take issue with implementing a system to help protect against such is just silly, with due respect.

God Bless


P.S. I appreciated the help!!!

Last edited by Ralph III; 02-12-2012 at 03:30 PM.
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Old 02-12-2012, 02:17 PM   #37
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Multiple Ground Rods, help


There is nothing wrong with improving or reassuring a properly grounded electrical system when installing whole house surge protection. It is required by the manufacturers ,square d , siemens etc... to insure the devices work as designed.

Without a test to prove he has 25 ohms or less on the first rod he has little choice but to add ground rod(s).

Most SPD manufacturers recommend that you have 2 eight foot rods. This is typical of most homes in the USA. He only has one he needs two.

Ralph

Are you using cascading surge protection ? That is the best method from what I have been researching. Also the power companies in many areas offer surge protection at the homes meter. I had them install it on my home and I installed a 3 rd 8' ground rod where it tested less than 25 ohms for the system. I recommend you pay for a test.

As you say your wanting to protect your home and electronic assests as best as possible so your doing exactly what you need to do. There is no 100% protection but you absolutely can prevent damage to your electronics in many events involving lighting using proper surge protection along with proper electrical system grounding as the two go hand in hand.

I was stating in my first post that you cannot achieve that with 4 foot grounding rods .... I wish you had a ufer ground .... .

What manufacturerz SPD are you looking at?
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Old 02-12-2012, 03:25 PM   #38
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Quote:
Originally Posted by Speedy Petey View Post
Again, what purpose do you think sticking a piece of metal rod in the dirt is going to do?
Everything. That is the only component of every protection system that does protection. Protection is always defined by where hundreds of thousands of joules dissipate.


Ralph is quite correct. Makes no difference whether a wire is overhead or underground. Any incoming wire can be a source of destructive surges if not earthed before entering a building. Nothing new. If any overhead or underground wire enters without earthing, then protection is compromised. These concepts have been understood for over 100 years. But are rarely understood by technicians who, for example, do not understand wire impedance and other critical concepts.

Essential for protection is single point earth ground. Anyone familiar with ground loops would better understand why single point earth ground is critical.

How important is earth ground? The NIST (US government agency that studies this stuff) is blunt:
Quote:
A very important point to keep in mind is that your surge protector will work by diverting the surges to ground. The best surge protection in the world can be useless if grounding is not done properly.
Ralph is also correct about eliminating sharp wire bends. Sharp wire bends, splices, or a wire inside metallic conduit is no problem when wiring does human safety. Any of those mistakes compromise what a 'whole house' protector might do. Make it ‘useless’.


No protector does protection. As the NIST says, protection is defined by how well a protector connects even direct lightning strikes (20,000 amps) harmlessly to earth. That earthing must be sufficient so that even direct lightning strikes cause no damage.

Damage to electronics is so routinely averted as to be considered human failure. For example, what defines each layer of protection? Earth ground. Install 1000 protectors inside the house. But with only one earth ground, that is still only one protection layer. But again, what does the protection? Not a protector. Where do hundreds of thousands of joules dissipate?

Ralph's 'whole house' protector is 'secondary' protection. Homeowners are strongly encouraged to inspect their primary protection layer. A picture defines the 'primary' protection layer:
http://www.tvtower.com/fpl.html

Earthing sufficient only to meet code must be upgraded to provide surge protection. Concepts such as single point earth ground, low impedance (ie a 'less than 10 foot' connection from breaker box to earth), wire not inside metallic conduit, and ground wires separated from other conductors - all are critical for surge protection. Impedance (not resistance) is critical. Surge protection is installed to earth 50,000 amp surges without any damage even to the protector.

Ufer ground were originally pioneered in muntions dumps so that direct lightning strikes do not cause damage. An earth ground is that important.

Last edited by westom; 02-12-2012 at 03:27 PM.
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Old 02-12-2012, 04:30 PM   #39
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Thanks Westom and Stubbie for you input! I truly don't get where some of the others were headed in debating what is clearly noted within the industry.

Stubbie, yes I am implementing a tiered level of protection starting at my load center>then to subpanels>then point of use, etc. I did research ufer grounds but noted they can be prone to damage when taking a large surge due to moisture retention? I'll just stick with installing a second ground rod as easier for me....

In adding to both of your excellent points though:

*from Safe Electricity.org, an EEC program.
Quote:
Should I Be Concerned about the Quality of My Electrical Grounding?
Yes. A surge protection device is only as effective as the electrical grounding circuit that is made available to it...
*from the IAEI (International Association of Electrical Inspectors)
Quote:
Article 250 – Grounding and Bonding
Establishing a solid foundation for a safe TVSS installation starts with the grounding and bonding system...
250-2. General Requirements for Grounding and Bonding
...The connections of the grounding electrode, grounding electrode conductor, and the bonding jumper are important to facilitate a safe, low resistance path to ground for any surge current being diverted by a TVSS. When adding a TVSS to an existing electrical system, it is important to reinspect the grounding system to ensure a safe and effective path for the surge current.
*from Emerson Industrial Automation (otherwise check such as Siemens)
Quote:
The safety and performance of any Surge Protective Device (SPD) system is dependent on correct grounding...

------------------------------------------------------------------------------------------

curiousB, I never said there were absolutely no benefits to underground power lines versus overhead! However, our power comes from overhead pole/lines thirty feet from our house. It only runs underground for that short distance.

A mute point however. Lightning strikes or other transient surges can cause damaging surges to households from miles away.

I'll catch ya'll on another thread.
Take care

Last edited by Ralph III; 02-12-2012 at 04:41 PM.
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Old 02-12-2012, 06:23 PM   #40
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Multiple Ground Rods, help


Quote:
Originally Posted by Ralph III View Post

In addition, Insurance companies themselves can deny a claim if there is an improperly installed breaker, otherwise non-compatible, as members here have noted themselves.
I know for a fact that this is untrue.




Quote:
Originally Posted by Ralph III View Post
You just completely contradicted yourself and single handedly destroyed your last point, when you stated, "ANYTHING done here is for the OP's peace of mind, not really much more than that".

Now you state, "Even though they help with nearby strikes....."
Not at all. And nice try BTW.
I never said ground rods don't do anything, although I don't think they do very much at all by themselves. I did say that anything more you do in YOUR situation will be for YOUR peace of mind.
I didn't read the instructions for your unit nor do I care to.
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Old 02-12-2012, 07:32 PM   #41
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Multiple Ground Rods, help


Quote:
Originally Posted by Speedy Petey View Post
I never said ground rods don't do anything, although I don't think they do very much at all by themselves.
Some protection system have no protector. But every protection system always has the one required component - earth ground.


For example, does a lightning rod do protection? Of course not. That rod, like a protector, is only a connecting device. That lightning rod is only as effective as its earth ground. As a FL couple discovered.

Lightning repeatedly struck one exterior wall. So they installed lightning rods. Lightning struck the same wall again. An investigation revealed their rods were connected to eight foot ground rods in sand. Lightning found a better path to deeper and more conductive soil. It was striking bathroom pipes that connected to more conductive earth.

The solution was simple. Better earthing with longer ground rods. Then lightning stopped striking that bathroom wall.

A lightning rod (or protector) is only as effective as the only item that defines protection. Earth ground. Geology is important. Where do hundreds of thousands of joules harmlessly dissipate? What defines how every protector works? Its earth ground.

Any protector that does not have that low impedance connection is ineffective. Either a protector connects energy to earth. Or a protector must magically block and absorb that energy. Where do hundreds of thousands of joules dissipate? A valid recommendation will always answer that question.

Plug-in protectors can be so grossly undersized as to disconnect from a surge as fast as possible. Leaving the appliance to protect itself (as reported by the indicator light). Sometimes that disconnecting device (typically a thermal fuse) does not disconnect fast enough. Then a house fire may result. Does not happen often. But it does happen. Even in Australia where a fire house burned down. Some rather sheepish firemen learned about power strip protectors the hard way.

Another reason for upgraded earthing. To absorb surges so as to protect plug-in protectors. Protection is always about where that energy dissipates. Grounding for surge protection is so critical that it must exceed code requirements. 'Low impedance' (not resistance) is a critically important parameter.

Last I heard, they were still arguing over the insurance on a large commercial building. Fire was traced to circuit breakers. Some insurance company was withholding payment. Meanwhile circuit breakers do not trip on surges. Circuit breakers and surge protection are two completely different topics and anomalies.

Last edited by westom; 02-12-2012 at 07:35 PM.
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Old 02-12-2012, 08:56 PM   #42
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I stated that Insurance Companies may possibly deny claims due to improper breaker installation/compatability and that other members have noted that as well.
Quote:
Speedy Petey; "I know for a fact that this is untrue".
Really? My brother-in-laws family owned an Insurance Company, although he wasn't involved in Home Owners policies, he could probably tell you a few things in regards to grounds for denying claims.


Anyhow, this is from Southwest Premier Home Inspection, LLC.
Quote:
"If there is ever an insurance claim on the home due to a fire or electrical problem, a mismatched breaker and panel voids the UL rating of the panel and therefore gives the insurance company a reason to deny the claim.
This is a quote by A_Lost_Shadow
Quote:
"As a word of warning, I've read that insurance companies can often weasel out of paying fire claims if they can find electrical modifications made without a permit. #1 (non UL approved) and/or #2(improper installation) could provide the justification they need to deny a claim".
With due respect Speedy Peetey, you're living in fairy land if you think an Insurance Company would never deny a claim with gross and improper electrical installation by homeowners.


Quote:
Speedy Peetey; "Not at all. And nice try BTW.
I never said ground rods don't do anything, although I don't think they do very much at all by themselves. I did say that anything more you do in YOUR situation will be for YOUR peace of mind..."
Speedy Peetey, this entire thread has been about my whole house surge project and whether I needed to install a second ground rod for it. However, you agreed with CuriousB who made the bold statement I should have little concern with transient damage, as my power ran underground, and as such I was "...solving a problem that doesn't exist.".

He of course made that comment before I noted we had indeed suffered from "transient damage"...

If you want to now limit your agreement specifically to the ground rod that is fine; however, I had already stated myself it was for my own "...piece of mind", if nothing else.(#26).

I still don't agree with you though and nor are you in a position to know whether I have adequate earth ground!


take care,
Ralph

Last edited by Ralph III; 02-12-2012 at 09:06 PM.
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Old 02-13-2012, 11:18 AM   #43
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Quote:
Originally Posted by westom View Post
Plug-in protectors can be so grossly undersized as to disconnect from a surge as fast as possible. Leaving the appliance to protect itself (as reported by the indicator light).
Nobody was talking about plug-in protectors, but westom is on a crusade against them. He googles for "surge" to post his 'wisdom'.

For reliable information on surges and surge protection try:
http://www.lightningsafety.com/nlsi_lhm/IEEE_Guide.pdf
And also:
http://www.nist.gov/public_affairs/p.../surgesfnl.pdf

Both say plug-in protectors are effective.

Quote:
Originally Posted by westom View Post
Sometimes that disconnecting device (typically a thermal fuse) does not disconnect fast enough. Then a house fire may result.
Since 1998 UL has required thermal disconnects for overheating MOVs (protection elements).

Quote:
Originally Posted by westom View Post
Another reason for upgraded earthing. To absorb surges so as to protect plug-in protectors.
Compete idiocy.

============================
The author of the NIST surge guide has written "the impedance of the grounding system to `true earth' is far less important than the integrity of the bonding of the various parts of the grounding system."

That is, work on short ground wires from entry protectors from phone and cable to a common connection point on the earthing system. An example of a ground wire that is too long is in the IEEE surge guide starting page 30. This is the same point made in post #38 by curiousB.

Ground rods suck. That is why the code wants a test for 25 ohms, or just use 2 rods. About everyone just uses 2 rods.

If you have a strong surge to earth of 1,000A and a miraculously low resistance to earth of 10 ohms with ground rods, the building 'ground' will rise 10,000V above 'absolute' earth potential. Much of the protection is that all wires - power, phone, cable, ... - rise together.

The OP's phone entry protector has a 10 ft ground wire to the earthing system. This is at about the maximum length you want but should be OK.

If you have a very near lightning strike, separate ground rods (like the one the OP suggests adding at the phone entry) can be at very different potentials. I would only connect the phone protector to the earthing system, not a bonded ground rod.

I agree with others that you don't want earthing from the subpanel. If you add earthing from the load center, the earthing wire loop back to the meter is in parallel with the neutral which is undesirable. Particularly if you add a surge protector at the meter base I would just extend the wire from the meter to a second rod.

Bends in the grounding electrode conductor are not a problem. Just don't make sharp bends.
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Old 02-13-2012, 12:26 PM   #44
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Originally Posted by bud-- View Post

.... The author of the NIST surge guide has written "the impedance of the grounding system to `true earth' is far less important than the integrity of the bonding of the various parts of the grounding system."......

Exactly as I stated. Ensure all your entrance utilitities are bonded to the same point.... Common bonding is the key. If you have utilities entering different sides of the house and grounding to different ground rods (or with very long wire runs to the ground rod) that is not a good formula.
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Old 02-13-2012, 04:37 PM   #45
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Quote:
Originally Posted by Ralph III View Post
I stated that Insurance Companies may possibly deny claims due to improper breaker installation/compatability and that other members have noted that as well.
Really? My brother-in-laws family owned an Insurance Company, although he wasn't involved in Home Owners policies, he could probably tell you a few things in regards to grounds for denying claims.


Anyhow, this is from Southwest Premier Home Inspection, LLC.
This is a quote by A_Lost_Shadow
I wasn't going to address this any further, but you are just inviting it.
LOOK at what you are saying.
- Your B-I-L's family, that never dealt with home owner's policies.
- A link to some home inspector's web site. Well, if it's written there is must be true, right? Sorry, but a home inspector is one of the last people I will take electrical advice from.
- A quote from someone on a message board saying "I've read that insurance companies can often..." Again, he read it somewhere, and if it's written it must be correct, right?





Quote:
Originally Posted by Ralph III View Post
With due respect Speedy Peetey, you're living in fairy land if you think an Insurance Company would never deny a claim with gross and improper electrical installation by homeowners.
And now you are putting words in my mouth, and directly contradicting what you are saying above where you say "..may possibly deny claims due to improper breaker installation/compatability ".
I NEVER used the word never. I also didn't say anything about "gross and improper electrical installations". These are YOUR words.
I am friends with the owner of one of the biggest insurance agent in my area, and according to him and others I have spoken with, the only time they can actually deny a claim is if poor work and the resulting damage is found to be done intentionally. In a case like this I think the last thing you should worry about is the insurance claim. I think the fraud police will be more of an issue.
This is not to say they will not drop you after the fact, but even then that is pretty common even for legitimate claims.


All this said, please do not bother to reply. I am done with this thread.

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