Question about bonding and grounding, am I too late??

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J

jenniferm

0
May 4, 2014
27
Rhome Texas
Ok so I spend hours reading posts here 3 years ago when I started building my in ground concrete block pool. Finally I am getting this thing finished. Concrete blocks already have rebar and concrete. Everything done. Liner is in and water is half full. Started getting quotes this week for an electrician to hook up the equipment. First one says that he needs to ground the pump with two 8 ft rods in the ground. Ok cool. Second company says that not only do they need to ground the pump but the pool needs to be bonded. He says copper wire buried 6 inches down all the way around, connected to the pump and connected to the water through the skimmer box. Ok, sounds interesting so I looked it up. Today the third guys come and tell me it is too late to bond because the rebar is already there so it wouldnt work anyway.

So which is it? Should I have it done or is it too late if I cannot connect to the rebar?
 
jenniferm said:
Ok so I spend hours reading posts here 3 years ago when I started building my in ground concrete block pool. Finally I am getting this thing finished. Concrete blocks already have rebar and concrete. Everything done. Liner is in and water is half full. Started getting quotes this week for an electrician to hook up the equipment. First one says that he needs to ground the pump with two 8 ft rods in the ground. Ok cool. Second company says that not only do they need to ground the pump but the pool needs to be bonded. He says copper wire buried 6 inches down all the way around, connected to the pump and connected to the water through the skimmer box. Ok, sounds interesting so I looked it up. Today the third guys come and tell me it is too late to bond because the rebar is already there so it wouldnt work anyway.

So which is it? Should I have it done or is it too late if I cannot connect to the rebar?
Click to expand...

I don't know if its too late, but you should ground (bond?) the pool... I'm just posting pics that you can see on my pool I'm building... just grounded everything, and inspector must see it.
 
Any electrician that used the word ground or talked about grounding rods should be removed from consideration. They don't understand pool electrical work.

If you can still get to the rebar to make wiring connections, you should be able to bond it.
 
Ok lets all slowwww down. Bonding and grounding are very different and should not be confused.

Grounding, as applies to pools, is connecting all electrical equipment to the service entrance neutral buss bar. Its covered in NEC Article 250 and for pools in NEC Article 680.6. Grounding of pools does not include ground rods.

Generally The NEC requires all electrical components of a pool, the pumps, heater, SWCG, utility plugs, lights, automation systems to be connected back to the service entrance neutral bus bar by an insulated ground wire. No bare copper, no using metal conduit as a equipment ground. Insulated ground wire and only insulated ground wire. The purpose of grounding is to direct a fault current back to its source by a low resistance path in such a manner so as to trip the overcurrent protection device (the circuit breaker) and prevent harm to humans.

Bonding, as it applies to pools, is installed to reduce voltage gradients in the pool area. NEC 680.26(A) In English that means that if any part of the pool structure or equipment does become energized (be it from a local source or a outside source) then the whole pool structure and equipment will be energized. If it's all energized then a human being cannot act as a conductor and does not get shocked no matter the source of the current.

The bonding rules can be complex but in summary a concrete pool must have its rebar shell connected to a copper bonding conductor in 4 different locations and the conductor must be solid #8. The deck or surface outside the pool should hace a rebar or copper cage around the pool extending three feet from the pool. You may use a #8 copper wire around the pool as a substitute in some jurisdictions. The water and all metal parts of anything within five feet of the water must be connected to the bonding loop including the pumps SWG and heater. Even if they are grounded. The bond wire must be connected by screw clamps listed by UL for that purpose.

So hire the second electrician and have him examine what you have and figure out a way to make it work and comply with NEC 680. You may need to chip up some concrete but I'm not there so I can't tell you the best solution.

If you have questions post on this thread. When does the pool open so I can come swim:kim:?
 
Accessing the rebar is an issue since it is a block wall pool the rebar rods are not touching. There is one piece of rebar per concrete block hole then the hole is filled with concrete. The pool is 28x30 so that is a lot of holes.

Since the rebar is encased in concrete and does not have contact with anything conductive why would it need to be wired in?

I am thinking I might have made a huge very expensive mistake.
 
allinspector said:
Do you have any pictures?

I remember seeing your build thread when i was planning my block pool.
Click to expand...

Here it is so far. We changed from a traditional in ground liner to a "natural pool" look with a black liner. That is partially why I stopped posting here. I know pool people look down on this because it isnt as pretty. I totally understand but I have kids and 3 dogs who love water and I did not want to spend a ton of money on a fitted liner just to have the dogs destroy it. The black liner is crazy thick and I do not think they can hurt it. I spent a lot of time on pinterest looking at natural pools. Seemed intriguing... till I could not find much about the pumping/filtering systems without paying someone. The idea is the plants keep the water clean and you use a bio filter to clean debris out. Seemed like a good thing till I really started thinking about the health of my family and I cannot risk some weird flesh eating bacteria or crypto just because I am too much of a hippy at heart lol So it is going to be some what of a hybrid pool. It will have a SWG and UV/Ozone system long with the DE pump. It fits our needs so that is all I care about. We added the plant zone so it will be more of fountain/decoration area now and a place for the pups and youngest daughter. Might put some plants secured in raised pots to add to the natural look.
There will be wood decking over the left and back walls overlapping the pool wall by 8 inches to hide the black liner. The front of the pool will be a flagstone walk in entry. Then the right side of the wall will be flagstone coping. The wall between the two on the left is lower so water will flow across and the top of that wall will be flagstone to hide the liner. Then the wall dividing the two sides in the middle will be flagstone. We tried to get the decking done last weekend but realized the water had to go in before we could secure the liner and cover it because since it is not a perfect fit things have to be folded and sealed as the water pulls it into place. I also have 2 tons of big river rock to cover the gravel we temp put in the plant zone to hold the liner. I know that stone/gravel will make keeping it clean much harder but it is what it is. It will help protect the liner from the dogs constant wear and tear and cover the ugly black liner. I might eventually have it removed and stone put in.

I am embarrassed to post these pics on a pool forum. It does not really fit here and the people at the pond forums do not like swim ponds lol I am stuck in the middle!! There are no "natural pool" forums.

the beginning


Then we let the project sit for two years. I fell and dislocated and basically shredded my knee so I was on crutches for a while. We had to reshape the inside because erosion and plants.


Finally getting materials! This was very exciting to see after 2 years of waiting. Almost had a problem, fed ex only had a pallet jack to deliver a 12 ft long 1025 pound liner. Luckily the stone guy helped out or we would have never gotten it off the truck


Liner in. Looks easy right? It took 4 adults almost 2 days to get it in. It was over 100 degrees, and that black material made it feel so much hotter. Plus it was 1025 lbs! It was ridiculous.


pups are ready to go for a swim!


kids are pretty excited too. I let them swim over the weekend but if I cannot get the pump system hooked up soon the water is going to get funky real fast :(



 
gwegan said:
Ok lets all slowwww down. Bonding and grounding are very different and should not be confused.

Grounding, as applies to pools, is connecting all electrical equipment to the service entrance neutral buss bar. Its covered in NEC Article 250 and for pools in NEC Article 680.6. Grounding of pools does not include ground rods.

Generally The NEC requires all electrical components of a pool, the pumps, heater, SWCG, utility plugs, lights, automation systems to be connected back to the service entrance neutral bus bar by an insulated ground wire. No bare copper, no using metal conduit as a equipment ground. Insulated ground wire and only insulated ground wire. The purpose of grounding is to direct a fault current back to its source by a low resistance path in such a manner so as to trip the overcurrent protection device (the circuit breaker) and prevent harm to humans.

Bonding, as it applies to pools, is installed to reduce voltage gradients in the pool area. NEC 680.26(A) In English that means that if any part of the pool structure or equipment does become energized (be it from a local source or a outside source) then the whole pool structure and equipment will be energized. If it's all energized then a human being cannot act as a conductor and does not get shocked no matter the source of the current.

The bonding rules can be complex but in summary a concrete pool must have its rebar shell connected to a copper bonding conductor in 4 different locations and the conductor must be solid #8. The deck or surface outside the pool should hace a rebar or copper cage around the pool extending three feet from the pool. You may use a #8 copper wire around the pool as a substitute in some jurisdictions. The water and all metal parts of anything within five feet of the water must be connected to the bonding loop including the pumps SWG and heater. Even if they are grounded. The bond wire must be connected by screw clamps listed by UL for that purpose.

So hire the second electrician and have him examine what you have and figure out a way to make it work and comply with NEC 680. You may need to chip up some concrete but I'm not there so I can't tell you the best solution.

If you have questions post on this thread. When does the pool open so I can come swim:kim:?
Click to expand...


That explanation is very helpful, thank you! I am just sad I did not read that before building! lol I knew I could probably build a pool but did not even look into the electrical because I figured I would hire someone when I was ready for it to go in. No sense in having it all hooked up at the beginning.
 

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Would using this Amazon.com: Burndy Waterbug Pool Water Bonding Kit Ul: Kitchen Dining to bond the water to the circut be effective if the rebar is not connected? Has to help right?

I totally do not understand electricity but I am trying to learn. So if the idea behind bonding is so everything is the same current so no shocky shocky if something goes wrong in the pump/wiring. The only things that could electrocute you would be things that were not bonded to the grid right? If you do not touch the rebar you do not get electrocuted correct?
 
1000 pound liner,, that sounds like a big job. Not laughing at you, but your statement about it being ridiculous and the 100 degree heat gave me a good laugh.

I did something similar with the rebar in the concrete block, they were individual pieces. I then poured in the concrete core filler. I didn't bond them. I did bond everything else, the aluminum pool coping, the ladders, and the pool equipment. I don't have any obvious problems with shock or voltage.
 
Starting with the basics:

Voltage is a relative property. You can't have a voltage without specifying what it is relative to. I may be at 50,000,000V relative to Pluto, but that really doesn't mean much. The concern is with things that are nearby. People default to voltages relative to ground, but don't usually specify it. Your outlets in your home are 120VAC relative to ground.

When two points are at different voltage, current will flow between them if it can find a path. People make acceptable paths, especially wet people.

Current flowing through your body is what injures or disables you when you are shocked. This happens when you contact two points that are at different voltages and the current flows through your body.

To prevent current from flowing through your body, you need to make sure you can't touch two points that are at different voltages.

By connecting everything you can touch while swimming together with a large wire, you bring everything to the same voltage. Water, deck, fence, light, ladder, dive stand, pump housing, SWCG, heater etc.. This is known as equipotential or equal voltage system.


It doesn't matter what that voltage is, as long as it's the same everywhere.

If I drop an extension cord in the pool, the water will be energized to 120V. Because of the bond system, the deck, fence, light, ladder, dive stand, pump housing, SWCG, heater etc. will also be at 120V so no current can flow through a swimmer's body if they touch two of those things.

Conductive things that aren't connected to the bond system may be at different voltages. This is the risk of not bonding something. There is no way to know or control the voltage of the object relative to the rest of the pool and equipment.
 
It is also relatively unknown that concrete, especially wet concrete, does conduct electricity. Tying in the rebar to the bonding is just an easy way to get the concrete bonded. In your case it doesn't help because the rebar isn't tied together. I think you need to bond the water. The bonding kit you found will work for that. Your concrete shell isn't going to be exposed to the water anyway, the liner will overlap it and insulate it.

I have built a couple of large koi ponds and know all about how hard it is to move that liner!
 
That makes sense. So if you do not come in contact with the rebar it should not be an issue since everything you touch will be bonded correct? If every other thing, the pump, swg, UV, and water are bonded it is good right?

The one electrician said the bond wire had to circle the pool, be buried 6 inches down, and 6 inches from the pool wall. If it is just touching dirt why would it need to circle the whole pool?
 
Ok you have a liner. That means you do not have to have to bond the shell. Your concrete block structure.It's not considered conductive. NEC 680.26(B)(1). But it is vitally important to bond the water and the deck.

And just to be clear, if you had plastered or painted the shell bonding is required.

- - - Updated - - -

the wire needs to circle the pool so that it "picks up" stray current and makes the entire pool area of equal electrical potential. So you are not swimming along grab the deck and get zapped.

- - - Updated - - -

The code prefers a rebar or copper grid extending 3 feet from the pool, as an alternative you can have the wire 18 to 24 inches from the pool 4 to 6 inches deep. Two wires six inches to a foot apart is better.
 
pooldv said:
It is also relatively unknown that concrete, especially wet concrete, does conduct electricity. Tying in the rebar to the bonding is just an easy way to get the concrete bonded. In your case it doesn't help because the rebar isn't tied together. I think you need to bond the water. Your concrete shell isn't going to be exposed to the water anyway, the liner will overlap it and insulate it.

I have built a couple of large koi ponds and know all about how hard it is to move that liner!
Click to expand...


omg had I known how heavy the liner was I would have torn down the stupid thing and thrown up an above ground pool! At the beginning of this year we actually decided this was too hard and tried to have 2 different pond companies finish the job. Neither would touch it :( They said since they didnt build the retaining walls they could not be sure they were done correctly. Pretty much they didnt want to touch with this hot mess. I wish they would have at least put the liner in!

Took us one day to put padding on the edges of the bricks and lay the underlayment. The next day we started on the liner first thing. WE quickly realized there was no way we could move it or even lift it with the dingo bucket to unroll it. I had to run to a pipe supply and buy a 12 ft steel pipe to put through the tube of the roll to hoist it up with the dingo bucket. Then it didnt just roll out like toilet paper lol It took 4 of us pulling and pushing on that thing just to get the end drug out and across to realize it was not centered! When we started unfolding the sides we realized it unfolded to the right one time and to the left 4 times. It was so hot that we could only be in there for 5 minutes at a time before it became unbearable. It was like you could not breathe. Plus that stupid stuff gets crazy hot. Gloves worked but you had to tuck it under your arms and it would touch your legs.

Now that we have done this I would do things differently if I had to do it again. I would just buy a fiberglass pool!!! This thing has cost $20,000 already and we still have the decking to do.
 
For a simple explanation, when the wire is touching the dirt it is creating a large area around the pool that is the same voltage as described above. Because the dirt has some water in it, it will conduct electricity. Albeit a poor conductor, the wire helps tie it all together. The dirt is acting the same as the concrete in pooldv's msg.

Air is one of the poorest conductor's ever, but we have all seen lightning. Lightning is basically a current flow between different voltages on the ground and in the clouds.

I am far from qualified to offer advise and if anything seems questionable defer to pooldv, JohnT or Gwegan.
 
jenniferm said:
That makes sense. So if you do not come in contact with the rebar it should not be an issue since everything you touch will be bonded correct? If every other thing, the pump, swg, UV, and water are bonded it is good right?
Click to expand...

Not just the rebar. The wet concrete is a conductor too. That's the reason for bonding the rebar. It indirectly bonds the concrete.
 
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