dslreports logo
site
 
    All Forums Hot Topics Gallery
spc

spacer




how-to block ads


Search Topic:
uniqs
18512
share rss forum feed


49528867
Premium
join:2010-04-16
Fort Lauderdale, FL
kudos:3
reply to nunya

Re: Surge Protection Residential Whole House

said by nunya:

That's incorrect. I drive a rod on every pool with a sub-panel. As long as it is bonded back to the main with a #6 or greater, it's perfectly compliant. It's not required, but it's not a violation.

Yes and even though it is not required, by doing so you are providing your customer with a considerably safer electrical system.

Wayne

--
Madness takes its toll, please have exact change ready…


49528867
Premium
join:2010-04-16
Fort Lauderdale, FL
kudos:3
reply to iknow

said by iknow:

that was for free air, assuming a .125" conductor 250 FT long.

That should be number six which is roughly .2 direct buried bare in contact with earth.

I get the feeling when you rerun the numbers you will find the impedance to be considerably lower.

Wayne
--
Madness takes its toll, please have exact change ready…


Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
Reviews:
·Millenicom
reply to 49528867

said by 49528867:

said by Jack_in_VA:

The contractor/electrician installed a ground rod for the panel. The inspector made him remove the ground wire and run a #6 back to the the main ground rod for the service. He stated only one ground point is permitted.

What a shame he didn't know better.

From my grounding manual published by RO Associates a leader in designing ground systems whose grounding and bonding for communications facilities course I attended a few years back.

»www.protectiongroup.com/Ro-Associates

[att=1]

Wayne

We're not talking communications faciltites


49528867
Premium
join:2010-04-16
Fort Lauderdale, FL
kudos:3

1 edit

said by Jack_in_VA:

We're not talking communications faciltites

None the less grounding and bonding is all the same regardless of the location, one may not to want to push it up to the level of a communications facility, but the basic principles remain the same.

And by the way, wasn't it you being critical of my ground system which was based upon the practices of the proper grounding and bonding of communications systems that began this diversion of this thread???

Wayne

Wayne
--
Madness takes its toll, please have exact change ready…


Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
Reviews:
·Millenicom
reply to 49528867

said by 49528867:

said by Jack_in_VA:

He did however make us install a second ground rod 5 foot from the existing rod and tie them together with #6 bare copper.

Be careful with advice and the best thing is to consult with your local electrical inspector. You can't go wrong doing that regardless of what you may see here.

That depends on the inspector, for example when the AHJ required you to install an additional ground rod at five feet from the existing ground rod he had you violate NEC 250.53(B).

Rule of thumb when installing additional ground rods they should be spaced at least the length of one (10 feet).

Wayne

You have to know Wayne in spite of what you think, say or write your opinions mean nothing except to you. The inspector is the only one who matters and if he says to do something do it.


49528867
Premium
join:2010-04-16
Fort Lauderdale, FL
kudos:3

said by Jack_in_VA:

The inspector is the only one who matters and if he says to do something do it.

Maybe in VA, but down here where we have the Board of Rules and Appeals (the BRA) and they have overruled a number of incorrect interpretations by the AHJ’s

Wayne
.
--
Madness takes its toll, please have exact change ready…


Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
Reviews:
·Millenicom

3 edits
reply to 49528867

said by 49528867:

said by Jack_in_VA:

Wayne I think I'll just stick with the recommendations of people knowledgeable and educated in the field of grounding.

Guess what you have been communicating with one of those.

Really? IMO I hardly think that someone who specializes in communications is fully qualified across the spectrum of industrial and residential grounding. That would be a truly a unique individual. That especially is true when your statements conflict with what some of us know and see practiced in the field and required in many areas.

quote:
I don't think you really believe you can claim the article was incorrect.

I will admit I was incorrect in that statement but please remember it was based on your incorrect interpretation/misreading of the article and your mixing of personal opinions into the subject.

To be specific;

Your comment “depending on the soil multiple ground rods can create potential differences between them causing problems.”

Once bonded together that is false.

If the bonding conductor reduces the potential difference to essentially "0", Then that would negate your belief that a ground rod would be needed.

Again your comment;

“as the article states telco, catv etc should be tied together and brought to a single point ground with the building ground. Note they do not have multiple ground rods in their article.”

If you carefully study the diagrams in the article you will notice there are no grounds depicted, as such I would say your point is irrelevant.

I have all my equipment grounded exactly the way they illustrate and I knew that long ago from my many courses and seminars on grounding and bonding.

Good luck there guy.

Don't need luck Wayne. I'm covered.

Wayne


Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
Reviews:
·Millenicom

1 edit
reply to 49528867

said by 49528867:

said by Jack_in_VA:

The inspector is the only one who matters and if he says to do something do it.

Maybe in VA, but down here where we have the Board of Rules and Appeals (the BRA) and they have overruled a number of incorrect interpretations by the AHJ’s

Wayne
.

Yes I know that but this is a small rural county and if a person wants to exist here he/she doesn't piss off the inspector. Is it right? No but a fact of life.

We've had people appeal the Wetlands Board decisions to the Circuit Court. Not a good outcome. The deck is stacked.


SmokChsr
Who let the magic smoke out?
Premium
join:2006-03-17
Saint Augustine, FL
reply to Jack_in_VA

said by Jack_in_VA:

Wayne I think I'll just stick with the recommendations of people knowledgeable and educated in the field of grounding. I don't think you really believe you can claim the article was incorrect.

I didn't read the article, but I did read Wayne's reply, and it looked dead on target to me. If we have anything wrong in our lightning protection systems in this area, you'll tend to find out about it rather quickly. It's not uncommon for anyone of my sites to take 3-5 direct strikes a week during the summer.

I did have one of my site's blasted by lightning last summer. I thought that was a bit odd, so I started looking and quickly saw that apparently my old tower grounding straps must have been out of date, and some nice person had come by and spent great effort on their part to assist me by removing all that old bad copper. Unfortunately they seemed to have forgotten to come back and put in new copper to replace it. Still I guess I should be grateful that they cared enough to do half the job for me.

nonymous
Premium
join:2003-09-08
Glendale, AZ
reply to Jack_in_VA

said by Jack_in_VA:

Really? IMO I hardly think that someone who specializes in communications is fully qualified across the spectrum of industrial and residential grounding. That would be a truly a unique individual. That especially is true when your statements conflict with what some of us know and see practiced in the field and required in many areas.

What was the old bell system five nines up time. Grounding did have tons to do with that. You have circuits all the way from a CO out many, many miles into the field. Without proper grounding besides up time the noise would be canceling any signal.
Bell Labs did know grounding.


SmokChsr
Who let the magic smoke out?
Premium
join:2006-03-17
Saint Augustine, FL
reply to Jack_in_VA

said by Jack_in_VA:

I have a detached garage with a 100 amp panel fed by a 100 amp breaker off the meter base. The contractor/electrician installed a ground rod for the panel. The inspector made him remove the ground wire and run a #6 back to the the main ground rod for the service. He stated only one ground point is permitted.

I don't doubt that. Many times I've had to "hide" my protection systems until after the inspector is gone. Once the inspector signs off, then I can make it right. If I left it the way the inspector wanted it the site would be blasted in days.

A few inspectors are good, and the rest only know how they think it should be. The NEC calls for 2 ground rods X feet apart at the electrical service entrance. This is a minimum requirement, and that's all some inspectors know, and they don't understand or care about what is involved in a higher level of protection.

In your particular example, what realistically would have been best was to add the second ground rod at the house entrance as required. Then to consider the out building as a separate entrance (which it really is) to that building and placing 2 rods at that location as well.


SmokChsr
Who let the magic smoke out?
Premium
join:2006-03-17
Saint Augustine, FL
reply to Jack_in_VA

said by Jack_in_VA:

You have to know Wayne in spite of what you think, say or write your opinions mean nothing except to you. The inspector is the only one who matters and if he says to do something do it.

Until he leaves, then do it right.
If you read the NEC, (not something I do very often) you'll see for a fact that the inspector is WRONG! That leaves the question, are you going to do a proper job or just make the inspector happy at the cost of lost equipment, and dangerous conditions?

"250.53(B) Electrode Spacing. Where more than one of the electrodes of the type specified in 250.52(A)(5) or (A)(7) are used, each electrode of one grounding system (including that used for air terminals) shall not be less than 1.83 m (6 ft) from any other electrode of another grounding system. Two or more grounding electrodes that are bonded together shall be considered a single grounding electrode system."


49528867
Premium
join:2010-04-16
Fort Lauderdale, FL
kudos:3
reply to SmokChsr

said by SmokChsr:

I did have one of my site's blasted by lightning last summer. I thought that was a bit odd, so I started looking and quickly saw that apparently my old tower grounding straps must have been out of date, and some nice person had come by and spent great effort on their part to assist me by removing all that old bad copper.

Here's a tip (from a guy who knows grounding) to prevent that from happening in the future.

»www.rwonline.com/article/no-sold···on/24805

Wayne

--
Madness takes its toll, please have exact change ready…


Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
Reviews:
·Millenicom
reply to SmokChsr

said by SmokChsr:

said by Jack_in_VA:

You have to know Wayne in spite of what you think, say or write your opinions mean nothing except to you. The inspector is the only one who matters and if he says to do something do it.

Until he leaves, then do it right.
If you read the NEC, (not something I do very often) you'll see for a fact that the inspector is WRONG! That leaves the question, are you going to do a proper job or just make the inspector happy at the cost of lost equipment, and dangerous conditions?

Since it has 4 #6 conductors and is only 20 feet away from the building ground rod system, there was or is no reason to change it.


Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
Reviews:
·Millenicom
reply to SmokChsr

said by SmokChsr:

said by Jack_in_VA:

I have a detached garage with a 100 amp panel fed by a 100 amp breaker off the meter base. The contractor/electrician installed a ground rod for the panel. The inspector made him remove the ground wire and run a #6 back to the the main ground rod for the service. He stated only one ground point is permitted.

I don't doubt that. Many times I've had to "hide" my protection systems until after the inspector is gone. Once the inspector signs off, then I can make it right. If I left it the way the inspector wanted it the site would be blasted in days.

A few inspectors are good, and the rest only know how they think it should be. The NEC calls for 2 ground rods X feet apart at the electrical service entrance. This is a minimum requirement, and that's all some inspectors know, and they don't understand or care about what is involved in a higher level of protection.

In your particular example, what realistically would have been best was to add the second ground rod at the house entrance as required. Then to consider the out building as a separate entrance (which it really is) to that building and placing 2 rods at that location as well.

Not needed. Installation is exactly what the inspector required.


49528867
Premium
join:2010-04-16
Fort Lauderdale, FL
kudos:3

1 recommendation

reply to Jack_in_VA

said by Jack_in_VA:

Really? IMO I hardly think that someone who specializes in communications is fully qualified across the spectrum of industrial and residential grounding.

Hate to tell ya this but if one is qualified to design a grounding system for a communications site then one is over qualified to design a residential grounding system.

That especially is true when your statements conflict with what some of us know and see practiced in the field and required in many areas.

Statements which have already been proven to be incorrect and not in compliance with both the NEC and published G&B standards.

If the bonding conductor reduces the potential difference to essentially "0", Then that would negate your belief that a ground rod would be needed.

Quite incorrect as bonding is not grounding and sadly you seem to fail to understand the difference between the two.

I have all my equipment grounded exactly the way they illustrate and I knew that long ago from my many courses and seminars on grounding and bonding.

Is that statement based on figure one which has multiple grounds bonded together which is the way I do things, which in turn you state is incorrect.

said by Jack_in_VA:

“Depending on the soil multiple ground rods can create potential differences between them causing problems.”

Gee Jack you seem to want it both ways.

I don't think you really believe you can claim the article was incorrect.

Really, then please explain why when illustrating the preferred method in figure two the designer violated the PANI rule, which in my opinion further brings into question the grounding and bonding skills of the author.

Don't need luck Wayne. I'm covered.

Just like the head of an Ostrich.

Wayne
--
Madness takes its toll, please have exact change ready…


Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
Reviews:
·Millenicom
reply to nonymous

said by nonymous:

said by Jack_in_VA:

Really? IMO I hardly think that someone who specializes in communications is fully qualified across the spectrum of industrial and residential grounding. That would be a truly a unique individual. That especially is true when your statements conflict with what some of us know and see practiced in the field and required in many areas.

What was the old bell system five nines up time. Grounding did have tons to do with that. You have circuits all the way from a CO out many, many miles into the field. Without proper grounding besides up time the noise would be canceling any signal.
Bell Labs did know grounding.

You should come here for an example of the perfect noise cancelling grounding. Mine was so bad and the Verizon techs unable to correct it I just gave up and went with Verizon Wireless Home Connect. Works fine and $30/mo cheaper.

Yes the old Bell System was fine when they had excellent trained knowledgeable employees. Now for the most part they have a bunch of high paid, union protected don't care workers. I had an uncle that worked for Bell Atlantic all his life and he would roll over in his grave if he saw the quality of workers now.

Kind of funny though lightning struck one of our power plant stacks one night. The only thing effected in the whole plant including generators was the phone system plant-wide. It blew up most of the glass tube spark gap enclosures the telco had on their incoming circuits. They spent a lot of time repairing/replacing them and getting our phone system back up.

laserfan

join:2005-01-14
Texas
reply to 49528867

said by 49528867:

said by nunya:

I drive a rod on every pool with a sub-panel. As long as it is bonded back to the main with a #6 or greater, it's perfectly compliant. It's not required, but it's not a violation.

Yes and even though it is not required, by doing so you are providing your customer with a considerably safer electrical system.

Great, that makes me feel better, thanks.

Regarding my "single ground at pole, not at house or garage, but another at pool" I can only add that driving ground rods around here is next-to-impossible given the rock we live on.

I don't know how well a ground rod can work in (almost) solid rock, but I can't imagine it's good.

At least we don't have to worry about shifting foundations, but for everything else the rock here (I don't even want to call it "rocky soil" cuz there ain't much soil!) is a huge PIA.


49528867
Premium
join:2010-04-16
Fort Lauderdale, FL
kudos:3
reply to Jack_in_VA

said by Jack_in_VA:

Not needed. Installation is exactly what the inspector required.

But your additional ground rod is not in compliance with the code nor is it installed in an effective manner, you see there is something known as soil resistance and placing ground rods too close together negates the effectiveness of the additional rods due to that resistance.




Wayne
--
Madness takes its toll, please have exact change ready…


49528867
Premium
join:2010-04-16
Fort Lauderdale, FL
kudos:3
reply to laserfan

said by laserfan:

Regarding my "single ground at pole, not at house or garage, but another at pool" I can only add that driving ground rods around here is next-to-impossible given the rock we live on.

You have a few options, depending on the thickness of the rocky layer if you can drill through the rock and get to the soil underneath you can buy ground rods which connect to each other to extend the length allowing you to get a decent amount of rod into the soil.

If you cannot go down you might be able to trench horizontally (below the frost line if applicable) and achieve the same results by laying a bare conductor in the trench if you are limited in the length of you trench you can add a product before backfilling such as Erico GEM to enhance your grounds effectiveness.

»www.erico.com/products/GEM.asp

Wayne
--
Madness takes its toll, please have exact change ready…


Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
Reviews:
·Millenicom
reply to SmokChsr

said by SmokChsr:

said by Jack_in_VA:

You have to know Wayne in spite of what you think, say or write your opinions mean nothing except to you. The inspector is the only one who matters and if he says to do something do it.

Until he leaves, then do it right.
If you read the NEC, (not something I do very often) you'll see for a fact that the inspector is WRONG! That leaves the question, are you going to do a proper job or just make the inspector happy at the cost of lost equipment, and dangerous conditions?

quote:
250.53(B) Electrode Spacing. Where more than one of the electrodes of the type specified in 250.52(A)(5) or (A)(7) are used, each electrode of one grounding system (including that used for air terminals) shall not be less than 1.83 m (6 ft) from any other electrode of another grounding system. Two or more grounding electrodes that are bonded together shall be considered a single grounding electrode system."

Given the two ground rods are bonded together with #6 solid copper wire it is considered a single grounding electrode system. That single system can't be less than 6 ft from another system.


49528867
Premium
join:2010-04-16
Fort Lauderdale, FL
kudos:3
reply to Jack_in_VA

said by Jack_in_VA:

It blew up most of the glass tube spark gap enclosures the telco had on their incoming circuits. They spent a lot of time repairing/replacing them and getting our phone system back up.

That’s old school, protectors used nowadays are hybrids providing gas tubes for the primary protection, backed by MOV for through thru protection and solid state protection facing the CPE.

Wayne
--
Madness takes its toll, please have exact change ready…


49528867
Premium
join:2010-04-16
Fort Lauderdale, FL
kudos:3
reply to Jack_in_VA

said by Jack_in_VA:

Given the two ground rods are bonded together with #6 solid copper wire it is considered a single grounding electrode system. That single system can't be less than 6 ft from another system.

Incorrect.

250.56 Resistance of Rod, Pipe, and Plate Electrodes.
A single electrode consisting of a rod, pipe, or plate that does not have a resistance to ground of 25 ohms or less shall be augmented by one additional electrode of any of the types specified by 250.52(A)(2) through (A)(7). Where multiple rod, pipe, or plate electrodes are installed to meet the requirements of this section, they shall not be less than 1.8 m (6 ft) apart.

Note.
Where multiple rod, pipe, or plate electrodes are installed to meet the requirements of this section, they shall not be less than 1.8 m (6 ft) apart.

In the code "shall not means something."

Wayne
--
Madness takes its toll, please have exact change ready…


Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
Reviews:
·Millenicom
reply to CajunWon

OP I found some good equipment for lightning and surge protection. I don't think a single device will cover everything that needs protection effectively.

Lightning & Surge Protective Devices


laserfan

join:2005-01-14
Texas
reply to 49528867

said by 49528867:

If you cannot go down you might be able to trench horizontally (below the frost line if applicable) and achieve the same results by laying a bare conductor in the trench if you are limited in the length of you trench you can add a product before backfilling such as Erico GEM to enhance your grounds effectiveness.

»www.erico.com/products/GEM.asp

Now there is something I've never seen (nor heard of) before! Can't imagine we can get it from our local HD/Lowes though!

Or maybe we can--the local HD does have very-large-sheets of copper w/ground connection for this very purpose. Pricey as heck of course.


Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
Reviews:
·Millenicom

2 edits

said by laserfan:

said by 49528867:

If you cannot go down you might be able to trench horizontally (below the frost line if applicable) and achieve the same results by laying a bare conductor in the trench if you are limited in the length of you trench you can add a product before backfilling such as Erico GEM to enhance your grounds effectiveness.

»www.erico.com/products/GEM.asp

Now there is something I've never seen (nor heard of) before! Can't imagine we can get it from our local HD/Lowes though!

Or maybe we can--the local HD does have very-large-sheets of copper w/ground connection for this very purpose. Pricey as heck of course.

Ground Plate - An electrode made to the requirements of NEC article 250-52 (d). The material used shall be a copper alloy intended for the purpose with a minimum thickness of 0.060”. Each plate shall expose a minimum of 5 ft2 of surface area to contact the soil. Grounding conductors shall be attached to the plate using a welding process. Splices made to the grounding conductor shall be made using a welding process. Dissimilar metals and solder connections shall not be allowed. Usually installed in a horizontal position.

Achieving an Acceptable Ground in Poor Soil-EC&M Article

Ground Rods and Touch Voltages

Ground rods are not enough to protect from lethal voltages.


49528867
Premium
join:2010-04-16
Fort Lauderdale, FL
kudos:3

In that article did you happen to catch this?

Always install multiple electrodes so they are more than 6 ft apart.

Wayne
--
Madness takes its toll, please have exact change ready…

laserfan

join:2005-01-14
Texas
reply to Jack_in_VA

Ok after reading all this stuff, and finding also this page on ground methods I am officially too smart for my own good.

The link says conventional ground rods suck, and even if I *was* able to somehow dig a 30" hole for a ground plate, it'd work poorly and last about a week.



This has been fun though. Maybe I'll play amateur chemist and build-my-own electrolytic...



Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
Reviews:
·Millenicom

said by laserfan:

Ok after reading all this stuff, and finding also this page on ground methods I am officially too smart for my own good.

The link says conventional ground rods suck, and even if I *was* able to somehow dig a 30" hole for a ground plate, it'd work poorly and last about a week.



This has been fun though. Maybe I'll play amateur chemist and build-my-own electrolytic...


It does show that there is way more considerations to effective grounding than many people realize. I especially liked finding an article on Touch Voltage. I had that in a seminar a long time ago.

You have rocks but Sandy soil is also a challenge but thankfully here I'm on the water and the water table is high enough for the ground rod to contact.

garys_2k
Premium
join:2004-05-07
Farmington, MI
Reviews:
·Callcentric
·callwithus
reply to laserfan

said by laserfan:

Ok after reading all this stuff, and finding also this page on ground methods I am officially too smart for my own good.

The link says conventional ground rods suck, and even if I *was* able to somehow dig a 30" hole for a ground plate, it'd work poorly and last about a week.



This has been fun though. Maybe I'll play amateur chemist and build-my-own electrolytic...


I suspect calcium chloride may be a good salt to use -- it's definitely a desiccant and would draw moisture from the atmosphere.