# in ground pool bonding



## stickboy1375 (Apr 28, 2012)

You better find out what NEC your state is on, when you pull your permit, sometimes they give out pamphlets on what is required to be done. Good luck and wire safe!


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## stickboy1375 (Apr 28, 2012)

vasben said:


> This is my plan, bond the light niche and the 2 ladders together. Should i bond the pump with them, or can I hook the pump to the ground rod out side the shed? Does the aluminum coping need to be bonded? Also since the pool is vinyl lined it doesn't need to be bonded?


You need to read article 680 of the NEC, and don't drive a ground rod, that will accomplish nothing.


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## Speedy Petey (Feb 1, 2004)

PLEASE read ALL of NEC 680 II

The fact that you are asking this:


vasben said:


> Should i bond the pump with them, or can I hook the pump to the ground rod out side the shed?


...tells me you need to SERIOUSLY read up on this installation. 

Or better yet hire a competent pro to do it. It will be money WELL spent.


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## stickboy1375 (Apr 28, 2012)

IMO, in ground pools are way above the average DIY person, and don't take this personally, because, yes, it is all doable by anyone, but the fact that the code section is a big one, it's impossible to give out EVERY detail of every installation. It's just too risky that you might miss that one thing, that could result in an injury or death.


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## andrew79 (Mar 25, 2010)

everything metal has to be grounded in a pool, right down to the rebar in the concrete. Like everyone else has already said, do your research before you start.


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## stickboy1375 (Apr 28, 2012)

andrew79 said:


> everything metal has to be *grounded* in a pool, right down to the rebar in the concrete. Like everyone else has already said, do your research before you start.


You mean bonded.


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## andrew79 (Mar 25, 2010)

ya sorry force of habit, i just call them all grounds. I guess i'll have to watch that on here. Don't want someone sticking the ground/bond from a lightning arrester into their panel. technically though everything around the pool gets bonded together and then gets grounded though 

we're doing a pool at the new four seasons hotel in toronto right now, every stinking drain,railing,underwater speaker, rebar, and every piece of aluminum trim around the edge gets a bond. Pool deck and pool both, there's wire running everywhere under the tiles lol.

thank goodness they decided against the shiny metal tiles for the bottom.


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## stickboy1375 (Apr 28, 2012)

andrew79 said:


> ya sorry force of habit, i just call them all grounds. I guess i'll have to watch that on here. Don't want someone sticking the ground/bond from a lightning arrester into their panel.


The terminology would be much simpler if they just changed it to earthing and bonding, and not intertwine grounding so much with earthing....


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## stickboy1375 (Apr 28, 2012)

andrew79 said:


> technically though everything around the pool gets bonded together and then gets grounded though



But the reason we bond everything is to keep everything at the same potential, BIG difference.


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## vasben (Jul 13, 2012)

OK, I read the 2011 nec 680 again. Bonding and grounding is a little confusion to me. Even though my pool is made of concrete block but since it has a vinyl liner it does not need to be bonded. The concrete around the pool will have some wire mesh in it so it needs to be bonded. I will connect the mesh to one of the ladders from there to the coping, to the other ladder, to the light, then to the pump. do i need to run a separate wire all the way around the pool?


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## Speedy Petey (Feb 1, 2004)

PLEASE, go read 680.26 over and over until you understand it. 

I for one and not going to copy and past the whole section and explain every little bit of it. 

Maybe someone else is willing to hold your hand on this one, but NOT me.


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## stickboy1375 (Apr 28, 2012)

I agree with speedy on this one, this will turn into a 1000 message thread.


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## stickboy1375 (Apr 28, 2012)

http://www.erbinspections.com/Forms & Guides/08_Article_680_Pools_and_Similar_Installations.pdf


Read through this, it should shed some light on what you're actually reading...Has pretty pictures of pool examples.


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## danpik (Sep 11, 2011)

vasben said:


> OK, I read the 2011 nec 680 again. Bonding and grounding is a little confusion to me. Even though my pool is made of concrete block but since it has a vinyl liner it does not need to be bonded. The concrete around the pool will have some wire mesh in it so it needs to be bonded. I will connect the mesh to one of the ladders from there to the coping, to the other ladder, to the light, then to the pump. do i need to run a separate wire all the way around the pool?


What type of decking material are you using. Stone, pavers, brick, concrete are all cosidered conductive surfaces and need to have a proper bond system installed. Do not move forward with this project untill you have a good understanding of why the bonding system is important and why it exists. I fix about 8-10 pools each year for customers who complain of electrical shocks when getting in and out of the pool, when touching the metal fence around the pool while standing on a wet deck, touching the ladder while standing on the deck, Etc, Etc, Etc. 

I am a pool owner and a member of a pool owners forum. This question comes up almost weekly.

I wrote this a while back to help some people with understanding the difference between bonding and grounding......

Bonding and grounding are two often misunderstood concepts. 

To start, we will look at grounding first. In the 120 volt electrical supply system for your pool pump there are 3 wires. Hot, Neutral, and ground. The hot and Neutral serve to move power from the source and back to the source so the pump can run. The ground wire in this system serves only as a non resistive conductive path back to source should something happen internally in the pump. For example, if, for some reason, the hot wire came in contact with the motor housing, the housing could become energized. Without the ground present, the housing could sit there waiting to shock any unsuspecting person or animal who happened to touch it. You would be the conductor to ground. Ground being the ground you are standing on. Now, because the resistive properties of the ground you are standing on are too high for the current to short circuit back to the source, it would most likely not trip the overcurrent protection (fuse, breaker). A couple of times here I have referred to "source". This is the power company transformer on the pole out at the street. The hot and neutral connections are both on this transformer and the returning current wants to get back to what is called the center tap on the transformer either via the grounding system or the neutral system. If there is a ground wire present in the circuit, the hot wire coming in contact with the motor housing would immediately trip the overcurrent protection as there would be a dead short in the system.

Bonding. The really mis-understood concept.
Have you ever experienced a static shock?...You know, you shuffle your feet across a carpet in the dry season and touch a metal doorknob. If you were bonded to that doorknob when you shuffled across the floor you would not have felt the shock when you touched it. Everything in the universe has what is referred to as electrical potential. Humans have a certain potential, a piece of steel has its own potential, water its own, etc, etc, etc. Most times this potential is not different enough to feel it. When you shuffle your feet on the carpet though, your potential changes from that of the doorknob. When you get close enough to the doorknob though both you and the doorknob want to get to the same potential. when that happens, a spark jumps the gap and evens out the potential. Fortunately there is little amperage behind it so there is no chance of getting electrocuted and since the event is a one time discharge you just dismis it. Now, lets look at your pool. your pool pump is grounded back to the source thru the ground wire. But, it still is at some level of electrical potential. Your pool water is at some other level of potential, your heater at its own level, heck, the ground you are standing on is at some level of potential. This means that all of the items in the vicinity have some varying degree of electrical potential. Under most circumstances these potentials are so close to each other that you never feel any kind of shock. however, every once in a while something happens to change the potential of one of the items. It could be a stray voltage induced from an underground electrical service, It could be a slight resistive leakage of current in your pumping system. What ever it is there is a potential difference. Now imagine you are getting out of the pool and as you touch the metal side of the pool you get the shock of your life. Hopefully not enough to kill you but a good shot none-the-less. Guess what? You just became the bonding conductor in the system. Had all of the components in the system been bonded together by the #8 bonding wire you never would have felt it. The wire is a non-resistive path between all of the components and since electricity is lazy, it will take the least resistive path. This bonding system will also protect you if you were standing on the ground and decided to touch the water to see how warm it is. If the bond is in place there would be no potential difference between the water and the ground even if there were a stray current floating around. 

Hopefully this helps clear some of this up


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## Speedy Petey (Feb 1, 2004)

danpik, EXCELLENT write up. Thanks. :thumbsup:


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## stickboy1375 (Apr 28, 2012)

I concur, that must have taken some time to write, but most helpful to the OP I'm sure!


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## danpik (Sep 11, 2011)

Thanks guys. That writeup was an evolution over several weeks this spring on the pool forum I am on. For some reason it seems like there was an unusually large amount of questions this spring about pool shocks (electrical). There was also a large amount of misinformation about grounding and bonding being thrown out there as well. I usually will not get into the specifics of how to do the bonding on the posters pools as I am not there to see them in person but, instead, do as you have and refer them to read the code on what is required. I wrote the explanation more to clear up the confusion on the difference between the two and the reasons both exist. It still amaizes me that some people think a ground rod stuck in the dirt will protect them. I also have fixed about 20 bonding issues on pools around here this summer due to handyman instalations. I had a toe to toe with one of them a couple of weeks ago about this very thing. I ultimatly blew him in to the code people in town for doing an unpermitted install on a pool.


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## Yoyizit (Jul 11, 2008)

danpik said:


> For some reason it seems like there was an unusually large amount of questions this spring about pool shocks (electrical).


Here's another. 
What was the lowest voltage that you had a complaint about? Was it from a man (women and children are more sensitive)?

Thanks.


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## Kandeya34 (Jun 20, 2015)

danpik said:


> What type of decking material are you using. Stone, pavers, brick, concrete are all cosidered conductive surfaces and need to have a proper bond system installed. Do not move forward with this project untill you have a good understanding of why the bonding system is important and why it exists. I fix about 8-10 pools each year for customers who complain of electrical shocks when getting in and out of the pool, when touching the metal fence around the pool while standing on a wet deck, touching the ladder while standing on the deck, Etc, Etc, Etc.
> 
> I am a pool owner and a member of a pool owners forum. This question comes up almost weekly.
> 
> ...


Many thanks to you for posting such an informative and well written explanation of an often misunderstood concept. Thanks for taking the time to do so.


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## concrete_joe (Oct 6, 2014)

stickboy1375 said:


> You mean bonded.


by nec verbiage, yes. but the last step which is not a requirement is to take that bonding to the gnd stakes and service gnd. so by verbiage, if its all "gnd'd" then such grounding makes a bonding grid.


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## stickboy1375 (Apr 28, 2012)

concrete_joe said:


> by nec verbiage, yes. but the last step which is not a requirement is to take that bonding to the gnd stakes and service gnd. so by verbiage, if its all "gnd'd" then such grounding makes a bonding grid.


I have no idea what you are suggesting...


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## concrete_joe (Oct 6, 2014)

stickboy1375 said:


> I have no idea what you are suggesting...


1) if the potential in center of pool is 1kv for just a 2x2 area but its only 0.001v at the edge, and the pool is 100% correctly done in bonding grid, what does the bonding do for that potential issue thats in center of pool?
2) salt water = ions, you are not likely to get shocked in a salt water pool where the railings are in the water (wire bonded or not).
3) if you "GND" everything (pool water, metal, decking), we know there's a diff between GND and Bonding by their definitions, but if its all GND'd then its all at same GND potential, therefore a conclusion is made, its also all equipotential bonded and the potential is not an unknown, we expect it to be close to zero. thus, stray current from a branch gfi that enters the "bonded/gnd'd" connection should trip the gfi.

i cant really dumb it down any more than that.


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## stickboy1375 (Apr 28, 2012)

IMO, you are overthinking why we bond swimming pools.


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## stickboy1375 (Apr 28, 2012)

You realize when we bond a swimming pool, we are not trying to bring the voltage to zero, but mask the voltage already existing. So let's say the grounded conductor from the utility company is 4 volts, since we bond our grounding conductors to the grounded conductor, the equipment grounding conductor at the pool motor is now 4 volts, so when we bond everyone at the pool that is metal we are actually energizing everything at 4 volts. This is how bonding works, we are just masking the problem, because it's impossible to remove it.


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## busman (Nov 7, 2008)

danpik said:


> The wire is a non-resistive path between all of the components and since electricity is lazy, it will take the least resistive path.


It is a great write-up, but the above is not strictly correct. Current takes all paths between point A and point B in its effort to complete a circuit. The current does split (current divider circuit from basic electrical theory) in proportion to the resistance of each path relative to the total resistance. In your example of bonding, there is some (very small) current flowing thru the human, but you are correct that the bonding wire takes MOST of the current.

I mention this because equipotential bonding is very effective at 120V. When you start getting into higher distribution voltages (above 20 kV) and transmission voltages, injuries can still occur, even with equipotential bonding in place. Bonding is still the safest bet, but injury is possible.

Mark


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## danpik (Sep 11, 2011)

concrete_joe said:


> thus, stray current from a branch gfi that enters the "bonded/gnd'd" connection should trip the gfi.


The GFCI will trip with or without a bonding grid. The "stray" voltage will cause an imbalance in the circuit that will cause the GFCI to trip. Bonding and grounding have nothing to do with a GFCI


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## danpik (Sep 11, 2011)

busman said:


> It is a great write-up, but the above is not strictly correct. Current takes all paths between point A and point B in its effort to complete a circuit. The current does split (current divider circuit from basic electrical theory) in proportion to the resistance of each path relative to the total resistance. In your example of bonding, there is some (very small) current flowing thru the human, but you are correct that the bonding wire takes MOST of the current.
> 
> I mention this because equipotential bonding is very effective at 120V. When you start getting into higher distribution voltages (above 20 kV) and transmission voltages, injuries can still occur, even with equipotential bonding in place. Bonding is still the safest bet, but injury is possible.
> 
> Mark


 Mark
I do agree with you 100% on the "least resistance" part. I may have to change the wording in that. Since most laypeople think that way I mistakenly wrote it that way. It probably should have been expressed differently.


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## stickboy1375 (Apr 28, 2012)

concrete_joe said:


> 1) if the potential in center of pool is 1kv for just a 2x2 area but its only 0.001v at the edge, and the pool is 100% correctly done in bonding grid, what does the bonding do for that potential issue thats in center of pool?


You'd have to have some pretty long arms to reach from the middle of the pool to the edge...  I'm not sure how your scenario would exist in the real world. 







concrete_joe said:


> 2) salt water = ions, you are not likely to get shocked in a salt water pool where the railings are in the water (wire bonded or not).


You should make this proposal in the next NEC.... see how that works out for you. 





concrete_joe said:


> 3) if you "GND" everything (pool water, metal, decking), we know there's a diff between GND and Bonding by their definitions, but if its all GND'd then its all at same GND potential, therefore a conclusion is made, its also all equipotential bonded and the potential is not an unknown, we expect it to be close to zero. thus, stray current from a branch gfi that enters the "bonded/gnd'd" connection should trip the gfi.
> 
> i cant really dumb it down any more than that.


Bonding does not bring the voltage to zero, it brings everything to an equal value, whatever that value maybe....


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## ritelec (Aug 30, 2009)

stickboy1375 said:


> we are just masking the problem, because it's impossible to remove it.


or is it?? 

https://www.youtube.com/watch?v=gHUqNCDwQj4


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## concrete_joe (Oct 6, 2014)

stickboy1375 said:


> You'd have to have some pretty long arms to reach from the middle of the pool to the edge..
> 
> Bonding does not bring the voltage to zero, it brings everything to an equal value, whatever that value maybe....


1) if 1kv is in middle and is in say 2sqft of surface water, and you are in that area, and you reach over and touch water that is at say 5v, you gonna get zapped, etc. you wouldnt need to be stretch armstrong, etc. yet correctly bonded system would not prevent the zap.
2) correct, bonding as it is defined does not bring it to zero, but if to take the bonding grid to service gnd and gnd spikes you have essentially "GND'd" everything and its now at "zero", thus gnd'ing everything is "_bonding down to zero_" which imho is a better way to do it.


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## stickboy1375 (Apr 28, 2012)

Not sure where you are getting zero from, but the pool is already technically bonded to the service grounding electrodes.... So if the pool was at 4 volts, so are the ground rods... You seem to be misunderstanding some theory...


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## stickboy1375 (Apr 28, 2012)

concrete_joe said:


> 2) correct, bonding as it is defined does not bring it to zero, but if to take the bonding grid to service gnd and gnd spikes you have essentially "GND'd" everything and its now at "zero", thus gnd'ing everything is "_bonding down to zero_" which imho is a better way to do it.


You can install as many ground rods as you want, but all you are doing is energizing more ground rods...


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## Jump-start (Sep 26, 2012)

As I said it before and I will say it again: Soil has no magical properties or special qualities. Soil is nothing but a giant resistor, in fact sand, silica and other ingredients in soil are used to make glass for high voltage insulators. 

With that said ground rods do not bring everything to zero potential, ground rods do not remove voltage and ground rods do not trip household breakers.


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## stickboy1375 (Apr 28, 2012)

Jump-start said:


> As I said it before and I will say it again: Soil has no magical properties or special qualities. Soil is nothing but a giant resistor, in fact sand, silica and other ingredients in soil are used to make glass for high voltage insulators.
> 
> With that said ground rods do not bring everything to zero potential, ground rods do not remove voltage and ground rods do not trip household breakers.


I think it's more than safe to say, ground rods are pretty useless at residential voltages...


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## Jump-start (Sep 26, 2012)

stickboy1375 said:


> I think it's more than safe to say, ground rods are pretty useless...


I personally believe ground rods are worthless, only required because of utility influences (MGN conductor) on the CMPs. In most parts of the world where TN_C_S and TN_S power is used (like we do) ground rods are not required by code, only bonding of anything that could become energized.


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## stickboy1375 (Apr 28, 2012)

Jump-start said:


> I personally believe ground rods are worthless, only required because of utility influences (MGN conductor) on the CMPs. In most parts of the world where TN_C_S and TN_S power is used (like we do) ground rods are not required by code, only bonding of anything that could become energized.


I know, it's a crazy world we live in, just think if you are a producer of ground rods, you would have lobbyist fighting for your product in every install to be code required.... :no:


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## Jump-start (Sep 26, 2012)

stickboy1375 said:


> I know, it's a crazy world we live in, just think if you are a producer of ground rods, you would have lobbyist fighting for your product in every install to be code required.... :no:


The code making process has turned into a money making auction for manufacturing reps.


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## InPhase277 (Feb 9, 2008)

In fact, driving more ground rods can actually introduce hazards in some cases. For example, on solar arrays that are required to have a seperate ground rod or light poles with ground rods. This can allow the huge voltage gradient of a lightning strike to drive a large current back into the building through the EGC.

On multi-grounded neutrals, I understand why the utility grounds their system. The dumb part is when we ground them again at the service. We either need to bring 4 wires from the transformer, or keep using 3 wires and stop driving rods and wiring them to the neutral.


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## InPhase277 (Feb 9, 2008)

Jump-start said:


> As I said it before and I will say it again: Soil has no magical properties or special qualities. Soil is nothing but a giant resistor, in fact sand, silica and other ingredients in soil are used to make glass for high voltage insulators.
> 
> With that said ground rods do not bring everything to zero potential, ground rods do not remove voltage and ground rods do not trip household breakers.


You know, the Earth is a great conductor, it has nearly infinite parallel paths. But the problem is it has no terminals. The resistance comes from us trying to connect to it. The resistance is at the earth-rod interface.


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## Jump-start (Sep 26, 2012)

InPhase277 said:


> You know, the Earth is a great conductor, it has nearly infinite parallel paths. But the problem is it has no terminals. The resistance comes from us trying to connect to it. The resistance is at the earth-rod interface.


Even then, you have stray voltage and other problems that arise with using the earth as a conductor. In some areas the soil is so dry would need to drive countless gorund rods miles down just to get a low reading. 


Your not wrong though, but to connect to the earth requires an insane amount of copper to the point its impractical.


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## Jump-start (Sep 26, 2012)

InPhase277 said:


> In fact, driving more ground rods can actually introduce hazards in some cases. For example, on solar arrays that are required to have a seperate ground rod or light poles with ground rods. This can allow the huge voltage gradient of a lightning strike to drive a large current back into the building through the EGC.
> 
> On multi-grounded neutrals, I understand why the utility grounds their system. The dumb part is when we ground them again at the service. We either need to bring 4 wires from the transformer, or keep using 3 wires and stop driving rods and wiring them to the neutral.




MGNs are an old practice, and considering stray voltage cases are on the rise Im sure they will disappear altogether with time. 

And you are correct, having multiple ground rods at different points rather than at one point actually increases the danger because ground rods will actually try to complete the circuit when a voltage gradient occurs across the earth. Much like this:


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## danpik (Sep 11, 2011)

Several years ago, I had to fix a shock problem on an above ground pool. Seems the pool owners wife and kids could feel a fairly good 'tingle" whenever they stood on the ground and touched the water. The husband did not feel it due to the fact that as a mason his hands were so calloused that I suspect he could grab a live 120 line and not feel it. The pool owner had the pool installed by a local "do-it-all" contractor that the pool store recommended. They came back out and tried some "things" to fix it including hooking the pump motor bonding lug to the grounding system. When I got there, there was no loop around the pool and no connections to either the pool shell or the water. The only "bond" in place was the connection to the grounding system and a #8 wire from the pump to a ground rod. I stuck my meter probes in the ground and into the water and saw almost 3 volts.

I installed both a water bond and a perimeter bond loop and corrected the problem. However, the pool owner was not happy and was thinking my solution was a "band aid" even after I showed him the pretty picture is the NFPA 70E book. He was thinking that it was something either his neighbor did with some underground wiring or it was from the high voltage power transmission lines about a mile from his house. I told him that was a possibility but he would have to get the power company involved. His reasoning was that electricity seeks water. At this point I knew I was up against "it". Since the shocking problem was gone he was comfortable but not fully convinced. 

Fast forward about a month. I was sitting in my kitchen when the power suddenly went out. Usually these events in our area may last for a few min. This time however it was longer, a lot longer. It seemed the entire northeast was blacked out. I called a buddy who works for National Grid and asked him what the situation was. He informed me there was nothing flowing anywhere. Even on the high voltage lines. 

This is when I got an idea. I went back to the customers house and since there was no power in the area I disconnected the bond wires from the pool. I then tested the voltage the same as before and got almost the same exact reading. My customer was now completely confused as I explained to him that due to the power outage the entire grid was down. I reconnected all of the bonding grid and the problem went away.


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## concrete_joe (Oct 6, 2014)

danpik,
you installed some bonding items, was that tied back to svc gnd or gnd rods?


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## stickboy1375 (Apr 28, 2012)

concrete_joe said:


> danpik,
> you installed some bonding items, was that tied back to svc gnd or gnd rods?



joe, he bonded the pool to the pool motor, which contains an EGC, which is tied to the neutral bus, which is tied to the grounding electrodes, which ties back to the utilities transformer... it doesn't get any easier than this.... It's ALL BONDED TOGETHER...


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## stickboy1375 (Apr 28, 2012)

concrete_joe said:


> danpik,
> you installed some bonding items, was that tied back to svc gnd or gnd rods?


What Dan did was energized the rest of the pool at 3 volts, thus eliminating any voltage potential...


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## InPhase277 (Feb 9, 2008)

Voltage is relative. It all depends on what you define "zero" to be in your system. For example, right now, I'm 1300 ft above sea level, but as far as I'm concerned, the floor in my house is 0 ft.

Grounding in the sense of "connected to the earth" is not important when it comes to swimming pool safety. What's important is that any potential present is spread across the area so that the is no difference between two points. That is what the term "equipotential" means: making the potential between two points equal. Current is what kills, and current only flows when there is a difference of potential from one side of a conductor to the other. Having a good conductor bonding all points together ensures that any differences are smoothed out.


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## concrete_joe (Oct 6, 2014)

InPhase277 said:


> Voltage is relative. It all depends on what you define "zero" to be in your system. For example, right now, I'm 1300 ft above sea level, but as far as I'm concerned, the floor in my house is 0 ft.
> 
> Grounding in the sense of "connected to the earth" is not important when it comes to swimming pool safety. What's important is that any potential present is spread across the area so that the is no difference between two points. That is what the term "equipotential" means: making the potential between two points equal. Current is what kills, and current only flows when there is a difference of potential from one side of a conductor to the other. Having a good conductor bonding all points together ensures that any differences are smoothed out.


its not exactly "relative" as in just pick a #. poco defines what their tolerance is for service. with a good poco service (lets say its 240v single phase) any hot to N or hot to "gnd" should be within poco specs. this usually means the N and "gnd" will not be 3 or 4 volts. surely a fault can indeed cause hot to N drop down to something like eg 110v which would then cause "gnd" to raise up some if referenced to "zero".

my point earlier was, if you bond it all per NEC, and then tie bond to service gnd, you should be in better protection than just bonding alone.

and gnd spikes, not sure why some think they are useless. have you ever seen lightning feelers reach up out of the ground?? a gnd spike that is 8-10ft down is usually damp at the bottom, and surface charge will seek that path more so than others.


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## Kandeya34 (Jun 20, 2015)

InPhase277 said:


> Voltage is relative. It all depends on what you define "zero" to be in your system. For example, right now, I'm 1300 ft above sea level, but as far as I'm concerned, the floor in my house is 0 ft.
> 
> Grounding in the sense of "connected to the earth" is not important when it comes to swimming pool safety. What's important is that any potential present is spread across the area so that the is no difference between two points. That is what the term "equipotential" means: making the potential between two points equal. Current is what kills, and current only flows when there is a difference of potential from one side of a conductor to the other. Having a good conductor bonding all points together ensures that any differences are smoothed out.


Beautiful explanation. Thanks. That helps a great deal in trying to understand the issues. I'm an "old fart" from the Korean War, so it takes some time to sink in. My pool will now be safe.


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## Jim Port (Sep 21, 2007)

Ground could be 1000 volts while the hots are 1120. Relative to ground the hot is 120 volts. The reference plane is considered 0, but may not actually be 0.


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## stickboy1375 (Apr 28, 2012)

concrete_joe said:


> InPhase277 said:
> 
> 
> > Voltage is relative. It all depends on what you define "zero" to be in your system. For example, right now, I'm 1300 ft above sea level, but as far as I'm concerned, the floor in my house is 0 ft.
> ...


What is wrong with you?


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## Jim Port (Sep 21, 2007)

The measurement of voltage depends on the difference of potential which requires a reference point. It is all relative to the point being measured between .


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## stickboy1375 (Apr 28, 2012)

concrete_joe said:


> this usually means the N and "gnd" will not be 3 or 4 volts.



Voltage drop will occur with any electrical system... 



concrete_joe said:


> my point earlier was, if you bond it all per NEC, and then tie bond to service gnd, you should be in better protection than just bonding alone.


No, the earth plays no role in this scenario. 



concrete_joe said:


> and gnd spikes, not sure why some think they are useless. have you ever seen lightning feelers reach up out of the ground?? a gnd spike that is 8-10ft down is usually damp at the bottom, and surface charge will seek that path more so than others.


They are useless...you can't seriously believe a 8' rod is going to control lightning which no one can explain to begin with...


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## stickboy1375 (Apr 28, 2012)




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## Jump-start (Sep 26, 2012)

concrete_joe said:


> > its not exactly "relative" as in just pick a #. poco defines what their tolerance is for service.
> 
> 
> You missed the point.
> ...


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## stickboy1375 (Apr 28, 2012)

680.26 Equipotential Bonding.
(A) Performance. The equipotential bonding required by
this section shall be installed to reduce voltage gradients in
the pool area.
(B) Bonded Parts. The parts specified in 680.26(B)(1)
through (B)(7) shall be bonded together using solid cop-
per conductors, insulated covered, or bare, not smaller than
8 AWG or with rigid metal conduit of brass or other iden-
tified corrosion-resistant metal. Connections to bonded
parts shall be made in accordance with 250.8. *An 8AWG or
larger solid copper bonding conductor provided to reduce
voltage gradients in the pool area shall not be required to be
extended or attached to remote panelboards, service equip-
ment, or electrodes.*


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## ritelec (Aug 30, 2009)

stickboy1375 said:


> 680.26
> (B) Bonded Parts. The parts specified in 680.26(B)(1)
> through (B)(7) shall be bonded together using solid cop-
> per conductors, insulated covered, or bare, not smaller than
> ...


Sir Stick,Phase and Jump,
If the remote panelboard (sub-panel) was not remote of the pool equipment and actually "AT" the location of the pool equipment, which needed bonding, would you also bond to the enclosure of that panelboard (and rod)?


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## ritelec (Aug 30, 2009)

ritelec said:


> Sir Stick,Phase and Jump,
> If the remote panelboard (sub-panel) was not remote of the pool equipment and actually "AT" the location of the pool equipment, which needed bonding, would you also bond to the enclosure of that panelboard (and rod)?


Also wanted to add, a "what if".

"What if" that panel at the pool had built in time clocks (the intermatic type)..
Since they had controllers in them would that also make that panel enclosure worthy of a bond?


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## stickboy1375 (Apr 28, 2012)

No....


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## stickboy1375 (Apr 28, 2012)

ritelec said:


> Sir Stick,Phase and Jump,
> If the remote panelboard (sub-panel) was not remote of the pool equipment and actually "AT" the location of the pool equipment, which needed bonding, would you also bond to the enclosure of that panelboard (and rod)?


It's already bonded through the EGC of the pool pump motor.... no other bonding is required. IMO, the reason we use #8 cu. from the motor enclosure to the rest of the the equipotential bonding requirements is purely for protection of this conductor.


Check out section 680.26 (4) and (5)


As a side note, a panel would have to be a minimum 5' horizontally from the inside wall of a pool, which also matches the distance of 680.26 (5), But 680.26 (A) FPN is pretty clear on what they don't require.


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## ritelec (Aug 30, 2009)

Thanks for that. 

I'm not sure 

(6)

It is electrical equipment and is associated with the circulation system. Especially if it's one of those panels with the built in time clocks. 

Would it really hurt to land the #8 to the panel enclosure? 

Thanks.

Couldn't find the fpn. Saw fpn for 680.27 not 26


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## InPhase277 (Feb 9, 2008)

ritelec said:


> Thanks for that.
> 
> I'm not sure
> 
> ...


No it wouldn't hurt, but it is just unnecessary.


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## concrete_joe (Oct 6, 2014)

Jim Port said:


> Ground could be 1000 volts while the hots are 1120. Relative to ground the hot is 120 volts. The reference plane is considered 0, but may not actually be 0.


at the surface the earth could act as an insulator, therefore you can have spots of charge that would derive potential. once into the damp depth electrons are free to seek out positive atoms, thus the earth acts as an infinite conductor.


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## Desertdrifter (Dec 10, 2009)

concrete_joe said:


> at the surface the earth could act as an insulator, therefore you can have spots of charge that would derive potential. once into the damp depth electrons are free to seek out positive atoms, thus the earth acts as an infinite conductor.


Could you draw me a picture of that?
I'm more of a visual learner.


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## concrete_joe (Oct 6, 2014)

clw1963 said:


> Could you draw me a picture of that?
> I'm more of a visual learner.


here you go. the top layer is dry and mostly silica (insulator). insulators can be charged. down below the dry layer is a damp region that allows electrons and ions to move more freely (conductor). the small "brown" regions in top layer are areas of local charge which cant freely move, thus they sit there until a conductor allows them to move. the red line is a gnd rod. if large charge of electrons decides to accumulate in the insulating layer when the charge is big enough it will forcefully move to seek positive ions (not unlike lightning), the gnd rod is an great sink for the flow. the lower layer is where electrons and ions can unite, and in general the net charge there is zero (as is on conductors). it is possible to charge a conductor but it will be short lived. you can have potential between a top layer charged zone and the earth below it, etc.


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## Jump-start (Sep 26, 2012)

concrete_joe said:


> here you go. the top layer is dry and mostly silica (insulator). insulators can be charged. down below the dry layer is a damp region that allows electrons and ions to move more freely (conductor). the small "brown" regions in top layer are areas of local charge which cant freely move, thus they sit there until a conductor allows them to move. the red line is a gnd rod. if large charge of electrons decides to accumulate in the insulating layer when the charge is big enough it will forcefully move to seek positive ions (not unlike lightning), the gnd rod is an great sink for the flow. the lower layer is where electrons and ions can unite, and in general the net charge there is zero (as is on conductors). it is possible to charge a conductor but it will be short lived. you can have potential between a top layer charged zone and the earth below it, etc.


That's lightening, or more precisely static charge. We are not talking about static charge, we are talking about a difference in potential from 50/60hz sine wave AC power.


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## InPhase277 (Feb 9, 2008)

I'm going to call bunk on that one. There is no place on the surface of the earth that is such a good insulator that a large island of charge could exist for very long. In the sky, yes. Not the surface.

The power companies discovered long ago that huge charges could build up in the ungrounded lines that spanned long distances, so they began grounding their systems. Then they discovered that if a transformer's insulation failed or high voltage lines contacted low voltage lines, a ground might help clear that fault. It might also help with lightning.

None of those things have anything to do with equipotential bonding around swimming pools. Like I said before, voltage is relative. There is no such thing as absolute voltage, because it is always measured as the potential to move charge from one place to some other place. One guy's 5 volts is some other guy's 400 volts, which is yet another guy's -71 volts. From a guy standing on the negative pole of a car battery, the positive pole is 12 volts higher in potential. A guy standing on the positive pole sees the negative pole as 12 volts lower. They are both right, just different points of view. Connecting the two poles together brings all the view points into line, so to speak, and everyone is on an equal footing. This is what equipotential bonding does. It makes sure no spot around the pool is at a different potential than any other spot. Grounding has nothing to do with it.


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## Jump-start (Sep 26, 2012)

InPhase277 said:


> I'm going to call bunk on that one. There is no place on the surface of the earth that is such a good insulator that a large island of charge could exist for very long. In the sky, yes. Not the surface.
> 
> The power companies discovered long ago that huge charges could build up in the ungrounded lines that spanned long distances, so they began grounding their systems. Then they discovered that if a transformer's insulation failed or high voltage lines contacted low voltage lines, a ground might help clear that fault. It might also help with lightning.
> 
> None of those things have anything to do with equipotential bonding around swimming pools. Like I said before, voltage is relative. There is no such thing as absolute voltage, because it is always measured as the potential to move charge from one place to some other place. One guy's 5 volts is some other guy's 400 volts, which is yet another guy's -71 volts. From a guy standing on the negative pole of a car battery, the positive pole is 12 volts higher in potential. A guy standing on the positive pole sees the negative pole as 12 volts lower. They are both right, just different points of view. Connecting the two poles together brings all the view points into line, so to speak, and everyone is on an equal footing. This is what equipotential bonding does. It makes sure no spot around the pool is at a different potential than any other spot. Grounding has nothing to do with it.


Only during lightening, and the big risk with operating a large system ungrounded is an arc fault causing a resonant condition with phase to ground capacitance. Industrial know uses high resistance grounded to overcome that. Earth is just a potential conductor in all that. 

But that's beside the point. An electrical system does not need earth, and earth certainly does squat when it comes to pools or equal potential. I think Joe fails to understand that. 


I normally leave threads like this, but I don't want a DIY to get the idea driving a ground rod somehow makes a pool safe, it does not.


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## Desertdrifter (Dec 10, 2009)

concrete_joe said:


> here you go. the top layer is dry and mostly silica (insulator). insulators can be charged. down below the dry layer is a damp region that allows electrons and ions to move more freely (conductor). the small "brown" regions in top layer are areas of local charge which cant freely move, thus they sit there until a conductor allows them to move. the red line is a gnd rod. if large charge of electrons decides to accumulate in the insulating layer when the charge is big enough it will forcefully move to seek positive ions (not unlike lightning), the gnd rod is an great sink for the flow. the lower layer is where electrons and ions can unite, and in general the net charge there is zero (as is on conductors). it is possible to charge a conductor but it will be short lived. you can have potential between a top layer charged zone and the earth below it, etc.


Like a capacitor?


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## concrete_joe (Oct 6, 2014)

Jump-start said:


> That's lightening, or more precisely static charge. We are not talking about static charge, we are talking about a difference in potential from 50/60hz sine wave AC power.


ok, well, stick a hot leg directly onto a single 10ft gnd spike and see what happens. 

stick a hot leg directly onto a non-gnd'd pool bond grid, would you swim in it? should be safe right, its all the same potential.

stick a hot leg onto a gnd'd pool bond grid, would you swim in it? the hot breaker should pop right?

not sure the reference to lightning. doesnt matter if its static charge or charge from a poco generator, need to have charge to have potential, etc.

and yes, the earth surface can hold charge, likely not very well, but it can.


----------



## InPhase277 (Feb 9, 2008)

concrete_joe said:


> ok, well, stick a hot leg directly onto a single 10ft gnd spike and see what happens.


I have done it several times, and the current flow is just a few amps. To get enough current to trip a 20 amp breaker, the resistance would need to be 6 ohms or less. Not very likely.



> stick a hot leg directly onto a non-gnd'd pool bond grid, would you swim in it? should be safe right, its all the same potential.


Yes, it should be. Having said that, only an idiot would swim in a pool that's been intentionally energized.



> stick a hot leg onto a gnd'd pool bond grid, would you swim in it? the hot breaker should pop right?


Yes, the breaker should trip. But again, only an idiot would do it.

You consistently miss the point of equipotential bonding. Grounding the bond grid to the service ground is already accomplished by the equipment ground to the pump motor. That is what will clear your intentional fault. You seem to think sinking rods into the dirt has something to do with tripping breakers. IT DOES NOT.


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## ritelec (Aug 30, 2009)

concrete_joe said:


> stick a hot leg onto a gnd'd pool bond grid, would you swim in it? the hot breaker should pop right?





InPhase277 said:


> Yes, the breaker should trip. But again, only an idiot would do it.



If the bond grid is bonded in one way or another to the system equipment ground conductor.. (motor, heater, light)

if it wasn't, I would think it not trip… there is an article that does mention that if there were no connections between the grid and egc.you have to make it.


----------



## InPhase277 (Feb 9, 2008)

Joe, inquiring electricians want to know why you only abbreviate ground in your posts? All the other words you type are full and your sentences complete, but you always type "gnd" for ground. Why?


----------



## InPhase277 (Feb 9, 2008)

ritelec said:


> If the bond grid is bonded in one way or another to the system equipment ground conductor.. (motor, heater, light)
> 
> if it wasn't, I would think it not trip… there is an article that does mention that if there were no connections between the grid and egc.you have to make it.


The code requires the bond grid be connected to the pump motor. The pump motor is required to have an EGC. Therefore, by connecting the bond grid to the motor, the grid is also grounded.


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## ritelec (Aug 30, 2009)

InPhase277 said:


> The code requires the bond grid be connected to the pump motor. The pump motor is required to have an EGC. Therefore, by connecting the bond grid to the motor, the grid is also grounded.


Yep… was just mentioning as I've seen bond wires at motors floating.. 

In such a case I don't think the breaker would trip, 
but as you mentioned if properly bonded the breaker should trip.. 

Dare I ??………. The breaker "WILL" trip :thumbsup:


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## stickboy1375 (Apr 28, 2012)

InPhase277 said:


> The code requires the bond grid be connected to the pump motor. The pump motor is required to have an EGC. Therefore, by connecting the bond grid to the motor, the grid is also grounded.


Some motors are double insulated, in this case, a bond wire must be left in case the pump is replaced in the future...

But, if there is no other connection between swimming pool bonding grid and equipment grounding system for the premises, then it must be tied to the motor circuit EGC....


680.26(B)(4)


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## Jump-start (Sep 26, 2012)

concrete_joe said:


> ok, well, stick a hot leg directly onto a single 10ft gnd spike and see what happens.


 A few amps flow as current returns back to its source. 



> stick a hot leg directly onto a non-gnd'd pool bond grid, would you swim in it? should be safe right, its all the same potential.


 What do you mean by none grounded? The ground rod will do nothing if that's what you are referring to. If you mean no EGC and bond grid is live there will be zero potential between bonded objects. 



> stick a hot leg onto a gnd'd pool bond grid, would you swim in it? the hot breaker should pop right?


 Yes, because the EGC will send enough current back to the source to trip the breaker. 



> not sure the reference to lightning. doesnt matter if its static charge or charge from a poco generator, need to have charge to have potential, etc.


 60Hz power doesn't work on charges. Its moving electrons. Earth is not a some type of magical storage tank. 




> and yes, the earth surface can hold charge, likely not very well, but it can.


 And where is the other plate of the capacitor in 60Hz power?


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## concrete_joe (Oct 6, 2014)

Jump-start said:


> 60Hz power doesn't work on charges. Its moving electrons. Earth is not a some type of magical storage tank.


when a generator is turning and no load is connected, where's those electrons going?


Jump-start said:


> And where is the other plate of the capacitor in 60Hz power?


wherever the load wires are, there's "C" there.


InPhase277 said:


> Joe, inquiring electricians want to know why you only abbreviate ground in your posts? All the other words you type are full and your sentences complete, but you always type "gnd" for ground. Why?


habit from doing electronic schematics, etc. its also faster to type, etc.


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## InPhase277 (Feb 9, 2008)

concrete_joe said:


> when a generator is turning and no load is connected, where's those electrons going?


Nowhere. They are waiting patiently for a complete circuit.


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## Jump-start (Sep 26, 2012)

concrete_joe said:


> when a generator is turning and no load is connected, where's those electrons going?
> 
> wherever the load wires are, there's "C" there.
> 
> habit from doing electronic schematics, etc. its also faster to type, etc.


Nowhere, and no the earth isn't inflating with them like a car tire.


----------



## stickboy1375 (Apr 28, 2012)

https://www.youtube.com/watch?v=j7r1UyuIgss


----------



## danpik (Sep 11, 2011)

Here is a good vid on ground rods too.

https://www.youtube.com/watch?v=Yg6G5VUSsWA


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## InPhase277 (Feb 9, 2008)

That's a good video and demonstrates so well what a ground DOES NOT do.

Also, Mike has been in front of a computer so long, you can see him struggle to figure out which end of the screwdriver to use :laughing:


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## concrete_joe (Oct 6, 2014)

https://www.youtube.com/watch?v=qNZC782SzAQ


----------



## stickboy1375 (Apr 28, 2012)

concrete_joe said:


> https://www.youtube.com/watch?v=qNZC782SzAQ


Did you watch this for your own benefit?


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## concrete_joe (Oct 6, 2014)

Jump-start said:


> Nowhere, and no the earth isn't inflating with them like a car tire.


so you think the magnetic field just doesnt do anything to the electrons when there is no load attached, the electrons simply ignore the mag field?


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## stickboy1375 (Apr 28, 2012)

concrete_joe said:


> so you think the magnetic field just doesnt do anything to the electrons when there is no load attached, the electrons simply ignore the mag field?





So are you mad bro? I mean, seriously, what are you trying to say?

Let's just be honest and accept what we truly understand in the field and the NEC...


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## InPhase277 (Feb 9, 2008)

concrete_joe said:


> so you think the magnetic field just doesnt do anything to the electrons when there is no load attached, the electrons simply ignore the mag field?


What do YOU think happens? Tell us what is happening in an open circuit generator...


----------



## Jump-start (Sep 26, 2012)

concrete_joe said:


> so you think the magnetic field just doesnt do anything to the electrons when there is no load attached, the electrons simply ignore the mag field?


Tell us what it does. But if you are talking about capacitive coupling, lol a ground rod does nothing about that. 

Again, I don't think you understand the theory and are trying to subvert everything we said thus far. 


But, Ill give you the benefit of the doubt, explain what happens.


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## danpik (Sep 11, 2011)

concrete_joe said:


> so you think the magnetic field just doesnt do anything to the electrons when there is no load attached, the electrons simply ignore the mag field?


So, then explain to me this... What happens when I pull my 5 horse portable generator out of the garage, fire it up with no load on it and let it run.


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## concrete_joe (Oct 6, 2014)

stickboy1375 said:


> Did you watch this for your own benefit?


i did, but if you watched it youll notice the argument is gnd rounds w/o egc. and as he says, gnd rods are not always a good idea. for a pool, gnd rods provide a path for stray current (lightinng, etc) which directs the flow away from the water where people might be. sure, at the expense of of having current flow across the egc to wherever that goes. and as he says, earth is an infinite conductor as i noted many posts back. the earth is ion plentiful, you dont actually need the other side of the generator in the earth to have some electrons move out of generator coil and seek pos in the earth.

gnd rods are not "useless" as some are saying, but they should be used in certain scenarios.



danpik said:


> So, then explain to me this... What happens when I pull my 5 horse portable generator out of the garage, fire it up with no load on it and let it run.


a generator w/ no load, hmmmm, put a high impedance digital volt meter across the output terminals, what do you get? it seems to suggest something is going on w/ the electrons even w/o load, almost looks like a capacitor. hmmmm, how w/o a load?



InPhase277 said:


> What do YOU think happens? Tell us what is happening in an open circuit generator...


its a mystery. i wonder if the gen coil gets warm from the electrons moving back and forth w/o a load? wire has ohms too.


----------



## InPhase277 (Feb 9, 2008)

concrete_joe said:


> its a mystery. i wonder if the gen coil gets warm from the electrons moving back and forth w/o a load? wire has ohms too.


It may be a mystery to YOU. But that's why you're Concrete Joe and not Electric Tim. Just stop pretending you know something about electrical theory and spewing misinformation here.

The fact is, the magnetic field drives the free electrons as far as they can go without a circuit, and then they sit there waiting to get to the side with the opposite polarity. It's like a fan blowing in an empty room. The fan isn't inflating the room to an infinite pressure, but the potential exists for air to move as soon as the door opens.


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## Jump-start (Sep 26, 2012)

concrete_joe said:


> i did, but if you watched it youll notice the argument is gnd rounds w/o egc. and as he says, gnd rods are not always a good idea.


 And you just admitted you were wrong:




> my point earlier was, if you bond it all per NEC, and then tie bond to service gnd, you should be in better protection than just bonding alone.


 




> for a pool, gnd rods provide a path for stray current (lightinng, etc) which directs the flow away from the water where people might be. sure, at the expense of of having current flow across the egc to wherever that goes. and as he says, earth is an infinite conductor as i noted many posts back.


 
Do you really believe a ground rod will protect people in a pool from lightening? If you truly had such a scenario you would need to go to NFPA780, which would require air strike terminals well above the pool. 





> the earth is ion plentiful, you dont actually need the other side of the generator in the earth to have some electrons move out of generator coil and seek pos in the earth.


 The earth is neutral like any conductor. A resistor siting on my workbench isnt ion plentiful. Lightening strikes ground only because of a charge difference that equalizes when lightening strikes. 





> gnd rods are not "useless" as some are saying, but they should be used in certain scenarios.


 If what you were saying was true they might have some merit. But the earth isn't an electron black hole. 




> a generator w/ no load, hmmmm, put a high impedance digital volt meter across the output terminals, what do you get? it seems to suggest something is going on w/ the electrons even w/o load, almost looks like a capacitor. hmmmm, how w/o a load?


 A high impedance meter is still a load. And the potential at the output terminals has nothing to do with the earth. 









> its a mystery. i wonder if the gen coil gets warm from the electrons moving back and forth w/o a load? wire has ohms too.


 
They are feeding other loads within the generator itself, so there might be some heating.


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## concrete_joe (Oct 6, 2014)

the fan example is not a good analogy.

oh, i know plenty about electrons :wink:

the no load gen creates a potential (typically @60Hz for US power) just as it does when there is a load, but you obviously hear little work being done w/ no load because the engine is just kinda idling there. its all about work. a DC gen might have a coil config that operates @400Hz. hmmm, i wonder why the higher frequency...... ah, thats a topic for another forum. 

and for clarity, i never said a gnd rod can replace egc, etc.

but back to nec and pool. if NEC says the equip needs egc this doesnt mean the pool itself is now connected to egc. what i was pointing out was that if the bonding piece is top notch (water, external grid, shell, gnd rods) then a hard tie from bond grid to egc seems like a good idea. and if you say nec technically connects bonding to egc because the equip needs an egc, then by that verbiage the bond grid is "grounded", so why not just call it "grounding the whole thing" because thats exactly what it is. the diff is, under current nec the bonding to egc happens via the water through the pump, thats not a good low ohms path, hence why i said to take #6 from bonding to egc (aka service ground).

but hey, if you think its better some other way then please explain why.


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## concrete_joe (Oct 6, 2014)

Jump-start said:


> Do you really believe a ground rod will protect people in a pool from lightening? If you truly had such a scenario you would need to go to NFPA780, which would require air strike terminals well above the pool.
> 
> The earth is neutral like any conductor. A resistor siting on my workbench isnt ion plentiful. Lightening strikes ground only because of a charge difference that equalizes when lightening strikes.
> 
> ...


1) a direct strike, no, a strike that hits 100ft away, yep.
2) hmmm, how does the charge diff get there to start with for a strike to happen? with a continuous imbalance of charge between earth and atmosphere there is always ions available to allow flow. net charge is always zero, etc.
3) air has impedance, i can take a volt reading through the air by measuring the electric field. not a load there since no electrons are flowing. a good digi volt meter does not allow flow, thus no load, etc.


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## stickboy1375 (Apr 28, 2012)

Joe, the reason we bond the water in a swimming pool is because more pools are becoming non conductive, so the water isn't being bonded with the rest of the premises, the problem with this scenario is that if a 2 wire appliance supplied via a gfci protected circuit was dropped into the pool, the gfci would not be able to function, we are not trying to bond the water to clear a fault, but to allow just enough milli amps to allow the gfci to function.


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## Jump-start (Sep 26, 2012)

concrete_joe said:


> 1) a direct strike, no, a strike that hits 100ft away, yep.


 Ground rod still does nothing. In fact a second rod at the pool will bring current up from the earth, through the EGC and then to the service ground rod. 



> 2) hmmm, how does the charge diff get there to start with for a strike to happen? with a continuous imbalance of charge between earth and atmosphere there is always ions available to allow flow. net charge is always zero, etc.


 
Google how lightening works. 






> 3) air has impedance, i can take a volt reading through the air by measuring the electric field. not a load there since no electrons are flowing. a good digi volt meter does not allow flow, thus no load, etc.



[/QUOTE]


Capacitive coupling, in the nano farad range. Yes wires will have a small amount of coupling to earth, conduit, ect but a ground rod does nothing. At most its what, milliamps?


----------



## concrete_joe (Oct 6, 2014)

stickboy1375 said:


> Joe, the reason we bond the water in a swimming pool is because more pools are becoming non conductive, so the water isn't being bonded with the rest of the premises, the problem with this scenario is that if a 2 wire appliance supplied via a gfci protected circuit was dropped into the pool, the gfci would not be able to function, we are not trying to bond the water to clear a fault, but to allow just enough milli amps to allow the gfci to function.


you mean some current from the two wire would get back to panel via the pool egc and thus the gfi protection feeding the two wire would trip? could this happen if the bonding didnt have a good low ohms path to the egc? could this small mA make its way through bonding and into a gnd rod back to service and gfi would trip?

if the bonding doesnt have gnd rods, and ohms path from bonding to egc was very high, how exactly would a gfi trip if a two wire item fell into the water?

no need to reply.... i think this thread is done.


----------



## Jump-start (Sep 26, 2012)

concrete_joe said:


> you mean some current from the two wire would get back to panel via the pool egc and thus the gfi protection feeding the two wire would trip? could this happen if the bonding didnt have a good low ohms path to the egc? could this small mA make its way through bonding and into a gnd rod back to service and gfi would trip?
> 
> if the bonding doesnt have gnd rods, and ohms path from bonding to egc was very high, how exactly would a gfi trip if a two wire item fell into the water?
> 
> no need to reply.... i think this thread is done.




Exactly, you know more than us when it comes to this stuff. :notworthy: Its us who don't understand you.


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## InPhase277 (Feb 9, 2008)

Joe, it is clear that you think of electricity as some sort of voodoo that only witch doctors comprehend. But the fact is it is a well defined property of matter that's well understood. And what you claim it to be, isn't what it is.


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## stickboy1375 (Apr 28, 2012)

Guys, we've obviously been trolled again, way to go all the Greg Zoll and concrete joes of the Internet to simply have nothing better to do but be an ******* on the Internet.


----------



## InPhase277 (Feb 9, 2008)

stickboy1375 said:


> Guys, we've obviously been trolled again, way to go all the Greg Zoll and concrete joes of the Internet to simply have nothing better to do but be an ******* on the Internet.


I enjoy it when it's worth it. :thumbsup:


----------



## Jump-start (Sep 26, 2012)

stickboy1375 said:


> Guys, we've obviously been trolled again, way to go all the Greg Zoll and concrete joes of the Internet to simply have nothing better to do but be an ******* on the Internet.


We have, but Id rather any DIYs reading these threads get the correct info then hurt themselves or someone else over trolls passing time.


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## ritelec (Aug 30, 2009)

how noble


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## Kandeya34 (Jun 20, 2015)

*Bonding Pool Hand Rail*

I'm in the process of installing a SS hand rail into the concrete deck of my pool. I'll be using aluminum sockets, cemented into the concrete slab surrounding the pool. I'll be installing two sockets to accept the new hand rail.
The sockets have a bonding lug to which I will attach the # 8 AWG bonding wire which will go directly to the grounding lug on the motor. While boring into the concrete, I encountered steel re-bar onto which the socket will sit. Is it necessary to mechanically fasten the socket to the re-bar or is it OK if it is just sitting on the re-bar and touching it? Thanks.


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## stickboy1375 (Apr 28, 2012)

The rebar should already be bonded, and make sure you bond both sockets in case they use plastic steps.


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## brric (Mar 5, 2010)

Kandeya34 said:


> I'm in the process of installing a SS hand rail into the concrete deck of my pool. I'll be using aluminum sockets, cemented into the concrete slab surrounding the pool. I'll be installing two sockets to accept the new hand rail.
> The sockets have a bonding lug to which I will attach the # 8 AWG bonding wire which will go directly to the grounding lug on the motor. While boring into the concrete, I encountered steel re-bar onto which the socket will sit. Is it necessary to mechanically fasten the socket to the re-bar or is it OK if it is just sitting on the re-bar and touching it? Thanks.


 Aluminum sockets won't last too long in concrete.


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## Kandeya34 (Jun 20, 2015)

What is an "approved" bonding lug which can be used to attach a bonding wire to a re-bar encased in concrete?


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## stickboy1375 (Apr 28, 2012)

in your case, just rent a concrete saw to get your #8 back to the pool equipment.


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## stickboy1375 (Apr 28, 2012)

Or, search for a PVC handrail and steps.


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## Jim Port (Sep 21, 2007)

The rebar should are be bonded. Instead of tearing up the concrete, bond to an accessible portion of the bond wire. There are rebar clamps if needed.


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## stickboy1375 (Apr 28, 2012)

Jim, I don't see an easy way to bond the cups other than cutting a channel back to the pool equipment.


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## Kandeya34 (Jun 20, 2015)

How do I test to determine if the re-bar is in fact bonded to the pool equipment? Can this be measured in some way with a multi-meter?


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## stickboy1375 (Apr 28, 2012)

What year was the pool built?


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## Kandeya34 (Jun 20, 2015)

Pool was built in the year 2000.


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## 70runner (Jul 5, 2015)

Newbie, retired EE, there's some great info in this thread. Not my intention to hijack as my questions seem relevant to the discussion. New owner of older pool, in ground, approx 20Kgal, pebble, built approx 1985. 

Embarking on electrical upgrade of pad, replacing Intermatic T32404R mech timer control with Intermatic PE653RC wireless control, new watertite conduit, etc. All equipment, 2 pumps, heater, blower, are 240v. 

Current bonding setup is code challenged. The 2 pumps and heater are bonded by jacketed, stranded wire. The blower is not bonded. The bonding wire is tied to a ground rod adjacent to the pad.

Given the age of the pool, would a pool structural bond (likely concrete/rebar) connection be expected? If not, what options are there to bond the pool equipment to pool structure?


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## InPhase277 (Feb 9, 2008)

I think the technical rules for equipotential bonding have been around quite awhile. Maybe back to the late 60s but I'm not sure. At any rate, assuming the pool deck is constructed using standard concrete techniques, you should be able to chip away at a corner of the deck you until you get to some wire or bar. I think I might do this all the way around at every corner, bonding with one #8 all the way back to the pump and heaters.

Edit: I'd also make sure everything is GFCI protected as well.


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## 70runner (Jul 5, 2015)

Would be a big job to retrofit a bonding loop to this pool. I may have to be satisfied with correctly bonding all the pad equipment and removing the connection to the ground rod.


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## stickboy1375 (Apr 28, 2012)

70runner said:


> Would be a big job to retrofit a bonding loop to this pool. I may have to be satisfied with correctly bonding all the pad equipment and removing the connection to the ground rod.


It would, I would check the town for a previous permit on the structure, also, the ground rod serves no purpose as far as bonding is concerned, the pool is already in the ground... :whistling2:


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## concrete_joe (Oct 6, 2014)

InPhase277 said:


> I think the technical rules for equipotential bonding have been around quite awhile. Maybe back to the late 60s but I'm not sure. At any rate, assuming the pool deck is constructed using *standard concrete techniques*, you should be able to chip away at a corner of the deck you until you get to some wire or bar. I think I might do this all the way around at every corner, bonding with one #8 all the way back to the pump and heaters.
> 
> Edit: I'd also make sure everything is GFCI protected as well.


which are what? micro rebar like Helix is very "standard" these days because rebar is too thick for the "typical" 3-4" thick pours. WWM is typical, just harder to keep positioned, etc. GRC is also getting popular.


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## InPhase277 (Feb 9, 2008)

concrete_joe said:


> which are what? micro rebar like Helix is very "standard" these days because rebar is too thick for the "typical" 3-4" thick pours. WWM is typical, just harder to keep positioned, etc. GRC is also getting popular.


Concrete with reinforcing wire and bar. As opposed to just dumping it in a hole.


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## Knucklez (Oct 21, 2007)

what about just testing the current situation to see if you have adequate step & touch potential. could be no action required if u can prove by measurement & analysis existing is sufficient.


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## concrete_joe (Oct 6, 2014)

Knucklez said:


> what about just testing the current situation to see if you have adequate step & touch potential. could be no action required if u can prove by measurement & analysis existing is sufficient.


i dont see anywhere where NEC allows for "testing for proof" to avoid the code. however, you never know, the AHJ has final say-so, so maybe such request (and proof) can get past the AHJ, but i doubt it.


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## Knucklez (Oct 21, 2007)

i'm not suggesting to avoid the code. i'm suggesting to test existing and make sure it acheives the purpose set out by the code. you can't SEE the ground grid.. doesn't mean its not OK. 

test/analysis to meet code its allowable in industry at commercial/industrial facility on their ground grid under transformers & main electrical substation. true both US and CAN. i stretched it a little to see if it could apply also to existing pool. after all, isn't this why we bond & ground? to make sure its safe for step & touch potenials (and also for good electrical operation)? and if you DID ground & bond.. how would u know its safe? its installed properly, visually OK'd by inspector.. but who ever tested it? i'm talking proper step & touch test/analysis, not ohm meter.


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## concrete_joe (Oct 6, 2014)

Knucklez said:


> i'm not suggesting to avoid the code. i'm suggesting to test existing and make sure it acheives the purpose set out by the code. you can't SEE the ground grid.. doesn't mean its not OK.
> 
> test/analysis to meet code its allowable in industry at commercial/industrial facility on their ground grid under transformers & main electrical substation. true both US and CAN. i stretched it a little to see if it could apply also to existing pool. after all, isn't this why we bond & ground? to make sure its safe for step & touch potenials (and also for good electrical operation)? and if you DID ground & bond.. how would u know its safe? its installed properly, visually OK'd by inspector.. but who ever tested it? i'm talking proper step & touch test/analysis, not ohm meter.


testing means nothing if the AHJ requires a visual inspection as part of their defined inspection process. if the AHJ cant see it then thats about the same as not being done even with all your tests, etc. 

i can ground my jbox's properly, close the cover, then do some gnd testing to show good results, and then show results to the AHJ. the results mean nothing to AHJ, my AHJ needs to visually inspect the gnd screw in each jbox, etc.


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## Speedy Petey (Feb 1, 2004)

Knucklez said:


> i'm not suggesting to avoid the code. i'm suggesting to test existing and make sure it acheives the purpose set out by the code. you can't SEE the ground grid.. doesn't mean its not OK.
> 
> test/analysis to meet code its allowable in industry at commercial/industrial facility on their ground grid under transformers & main electrical substation. true both US and CAN. i stretched it a little to see if it could apply also to existing pool. after all, isn't this why we bond & ground? to make sure its safe for step & touch potenials (and also for good electrical operation)? and if you DID ground & bond.. how would u know its safe? its installed properly, visually OK'd by inspector.. but who ever tested it? i'm talking proper step & touch test/analysis, not ohm meter.


The point is, under the NEC there are NO guidelines or parameters for such testing in this type of installation. This is not a grounding electrode that can be tested to 25 ohms.


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## wease (Dec 5, 2006)

I was hoping this thread would have my answer but it doesn't, so....

I am replacing the coping and decking around my pool. We are going with the grass look and I am curious about the bonding. Grass is not conductive. Not even sure how bonding would even be effective in that case. So, is that still required? All we are doing is applying a new coping on top of the bond beam. It is a brick material.

?


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## danpik (Sep 11, 2011)

You will need to run a bond wire around the perimiter of the pool just as if this were an above ground pool. You need to tie the grass area voltage potential to the grid just as if this were a concrete deck. Grass is very conductive when wet. The coping, being cemented to the beam, will be bonded thru the mortar. I don't have my code book here at the moment so I am putting this out there as a guide...the wire needs to be 6" deep and 18" away from the pool edge. Since this is the minimum code, and knowing how wet the ground can get around a pool, I would consider adding a second bond wire about 2' further out from the first one to pick up any possible voltage gradients.

Edit... The bond wire around the pool also should be tied to the shell bond grid (if concrete) or to the steel shell at 4 equally spaced points around the pool as well. Adding more is permisible


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## brric (Mar 5, 2010)

No bonding necessary for non-conductive materials.


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## wease (Dec 5, 2006)

Saw this:

(2) Perimeter Surfaces. An equipotential bonding grid shall extend 3 ft horizontally beyond the inside walls of a pool, outdoor spa, or outdoor hot tub, including unpaved, paved, and poured concrete surfaces. The bonding grid shall comply with (a) or (b) and be attached to the conductive pool reinforcing steel at a minimum of four points uniformly spaced around the perimeter of the walls of a pool, outdoor spa, or outdoor hot tub.

unpaved?


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## Jim Port (Sep 21, 2007)

I would consider the grass as unpaved.


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## brric (Mar 5, 2010)

wease said:


> Saw this:
> 
> (2) Perimeter Surfaces. An equipotential bonding grid shall extend 3 ft horizontally beyond the inside walls of a pool, outdoor spa, or outdoor hot tub, including unpaved, paved, and poured concrete surfaces. The bonding grid shall comply with (a) or (b) and be attached to the conductive pool reinforcing steel at a minimum of four points uniformly spaced around the perimeter of the walls of a pool, outdoor spa, or outdoor hot tub.
> 
> unpaved?


A bonding grid should have been installed when the pool was installed.


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## wease (Dec 5, 2006)

Pool was installed 40 years ago. Still applicable? I have rebar coming up at various points around the pool. I'll just tie into those as the code states and done....correct?


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## danpik (Sep 11, 2011)

Was there rebar in the concrete? If so, that was your bonding grid. The rebar you mentioned "coming up at various points around the pool"... is this tied to the shell of the pool?. if so, attach the perimiter grid to thos at at least 4 points around the pool.

Keep in mind, the bonding that the NEC wants to see is not meant as a form of punishment. It is meant as a means to protect you and others from voltage gradients that exist. On A pool forum I am a member of, this question comes up all the time and people are trying to figure out a way around installing it... if there are certain exclusions, Coatings that can be used, etc. I don't understand why. Anything that can protect you is good...right


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## wease (Dec 5, 2006)

Thanks Dan. There is rebar coming up at the midpoint of the bond beam and up from the sides of the pool in the dirt. Are these both a part of the grid? Suppose I can check for continuity.

Definitely not looking at this as punishment. Just don't want to pull a permit. The work I'm doing is light work in terms of coping and decking and none of it requires a permit. But the bonding "might" which would not be cool for permit reasons.


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