bonding vs grounding question

[cptserious]

I was reading the below post yesterday and thought my bonding could be bad; however, when I went back out to the pool after a few hours, I no longer felt that shock/sting on the open cuts/sores on my hands. What prompted me to search the threads is that I had just finished hosing off the filtration bags in my Desjoyaux pool and turned the pump back on when I stuck my hand in the water and felt the shock/sting. That was around 8:30 PM and when I went back out at 11:30 PM, I could no longer feel it. Is it because turning off the pump then turning it back on forced the voltage to balance out before no longer feeling the current or is something else happening?

I have not yet tightened down the bonding wire (which I assume is the bonding wire because it comes out of the ground and is a bare metal copper wire) but when I first opened the pool, I tightened it pretty good with tools. The only other thing I can think of is that instead of using the grounding terminal on the controller board of the Jandy variable speed ePump, I used the grounding screw that was fastened to the controller board housing unit.

Any help would be greatly appreciated.

Electrical shock from my pool water! - Page 2

 

[Razorhog]

My advice is to get a qualified electrician out there and take a look.

 

[Bama Rambler]

Is the bonding loop ran to all the equipment around the pool (pool walls, decking rebar, pump, swcg, lights, etc.)?
Bonding lugs are almost always external on the equipment.

Your pump should have two lugs. One in the electrical compartment is for grounding and one external is for bonding. Both should have a wire ran to them. The grounding terminal should have a green wire running back to the power panel.

 

[danpik]

Is your water bonded?
Dan

 

[borjis]

Also, if the bonding lug and the bonding wire on the pump look green and corroded, remove
the wire and clean the lug and the wire with a 3m scruffy pad to shiny copper. Inspect
any other bond lugs as well to make sure they have a good clean connection.

My last pool had the bonding lug and wire not even connected!

So I cleaned them up and attached them.

 

[Sparkmaster]

My quick advice is get a meter and put one end of the meter to the neutral or ground of a outlet (usually I would use a extension cord). From there I would go around and touch metal or water with the other end of the meter and see if you get anything. This way you can see if there is any voltage while the pump is running or not. If you do see voltage, I would do this as a quick test by grabbing a ground somewhere like the meter ground rod and run it to where it showed voltage. This may trip the breaker responsible for the leak or remove the leak to ground.

 

[pooldv]

More here about bonding, Pool School - Bonding vs Grounding

If you feel a shock then there is an issue with your bonding. This is a potentially deadly situation that needs to be addressed by a pro.

 

[cptserious]

Thank you Razorhog. I finally got an electrician out to take a look and he definitely found some voltage issues; however, I am not sure how much I trust the information other than voltage occurring. I say that because when I got home after talking with him in the morning, I found a grounding rod driven into the ground near the equipment pad with the wire leading to the neutral strip within the electrical panel. I could be wrong but my first instinct was, "this is not supposed to be this way."

Am I wrong?

I finally did a small test with my analog multimeter. I put some water from the pool onto the concrete deck then put one lead into the water and one lead into the wet concrete. Sure enough, voltage reading of just under 2 volts. When I touch dry concrete, no reading. I suspect that the rebar the concrete contractors used to install the concrete deck extension is what is causing stray voltage to enter the old concrete deck and thus allow for the difference in voltage. I may attempt this fix. Cut up a small trench of the new concrete, run a #8 copper wire connecting all the rebar back to the existing copper wire coming out at the equipment pad, and test again. Even if this doesn't fix the problem, what harm could it cause since I am thinking that the entire concrete deck will have to be pulled up.

Thoughts?

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Hey Bama Rambler, unfortunately, I do not know if the bonding loop hits the deep end ladder and the two shallow end railings or the light but I know the pump and SWCG are connected. The only interesting thing is that the power box for the SWCG is what is connected and not the actual SWCG which I am guessing is the proper way since the electrical box is where the current would be coming from. Now, I don't know if the water would then be bonded by this since the cells of the SWCG actually touch the water or if that is not the case.

I do have the ground terminal for both the pump and the SWCG connected. Only question I have is that my Jandy pump has two ground connections. One that is connected to the controller board where L1 and L2 are connected and a ground screw in the housing box itself. Should I connected the ground screw connected to the housing box on the pump to the ground connection on the controller board?

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Hey danpik, I thought the water would be bonded by the deep end ladder when it was in the pool but that was removed by the electrician for testing purposes so either the bonding wire is cut since the voltage still occurred or there was never a bonding wire ran around the components and the copper wire coming out of the ground is connected to a grounding rod driven deep in the earth (I kind of doubt that would be the case). The only other thing I can think of is that the copper wire is coming from a direct connection to the existing rebar that was used in the pool shell. The unfortunate part is that I was not part of the original pool installation and it would appear the two pool companies involved are no longer in business. Shocker.

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Thank you borjis. They do look a little on the non-shiny side so I will clean them up. I didn't even know what to use to clean them thoroughly so that is helpful.

 

[dloki]

Thank you Razorhog. I found a grounding rod driven into the ground near the equipment pad with the wire leading to the neutral strip within the electrical panel. I could be wrong but my first instinct was, "this is not supposed to be this way."

Am I wrong?

You are not wrong, the only connection to a grounding electrode should be made in at the "service equipment" which in general would be wherever the main disconnect for your house is located. In no case would it be connected to a remote sub panel neutral bar such as one located at the equipment pad.

The rebar in the pool deck would be required to be bonded per code so if you are getting a reading between the pool deck and the water it would make me suspect there is no proper water bond. In most cases the metal ladder, a metal section of pipe in the plumbing or a metal strip in the skimmer can act as the water bond. You should validate you have one of these in place and if the metal ladder is the water bond make sure the cups that are in the pool deck are clean and tight, often they are AL and all corroded and the retainer is not tight.

 

[cptserious]

Thank you pooldv. I have contacted two pool builders to get them to come out and check things. Unfortunately, I think I might be in a spot where the pool builders are not extremely knowledgeable only because the questions I've asked have not necessarily been answered in the manner or with the confidence I would expect. Most of them divert back to grounding which, as I have read in that article, are not the same things.

 

[dloki]

Here are some pictures of a bonding wire attached to the anchors for a ladder and handrail before the pool deck was placed. All of the rebar was also bonded to the same continuous bonding ring.





I would also say you can look up article 680 of the NEC, specifically section 680.26.

 

[pooldv]

Bonding should be #8 swg bare wire.

 

[cptserious]

Thank you @dloki. I know that the new rebar added to the new pool deck was NOT bonded (i.e. no copper wire was secured to it and run back to the copper wire at the equipment pad). I have noticed that with the ladder out of the water, the current between pool water and wet concrete is stronger which would lead me to believe that it was in fact being bonded but perhaps not enough. I've noticed some corrosion on the cups so much so that I am not sure if they are metal or actual concrete. My guess would be that they are actually metal and maybe I need to clean them well. How would I go about cleaning those cups thoroughly? 3m scruff pad like borjis mentioned?

Secondly, the rebar that was added to the concrete is more than 3 feet from the pool edge in some places. I remember reading that code is outside of 3 feet would not require bonding. Is that accurate?

Lastly, if I were to clean those cups and reinsert the pool ladder, could that possibly fix the issue? My guess is potentially yes because the pool water is at a certain potential and the wet concrete at a different potential given that they are no longer connected. Am I wrong?

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Thank you pooldv. I've already researched the cost of a 500 foot spool which ironically is cheaper than buying by the foot by the tune of almost 200 feet.

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Thank you dloki! I noticed that those copper wires are not bare. Will that pose a problem?

 

[cptserious]

Thank you dloki! I noticed that those copper wires are not bare. Will that pose a problem?

 

[dloki]

Only the bonding ring is required to be bare for contact with the earth, in this case the rebar is acting as the bonding grid. If there was no rebar in the pool deck then yes it would need to be bare and buried 4-6" below grade.

NEC Article 680.26(B) The parts specified in 680.26(B)(1) through (B)(7) shall be bonded together using solid conductors, insulated covered, or bare, not smaller than 8 AWG or with rigid metal conduit of brass or other corrosion-resistant metal
1 - Conductive pool shells
2 - Perimeter Surfaces
3 - Metallic Components
4 - Underwater Lighting
5 - Metal fittings
6 - Electrical Equipment
7 - Fixed Metal Parts

Part 2 is the pertinent section here - the perimeter surfaces would include the pool deck:

680.26(B)(2) The perimeter surface shall extend for 1 meter (3 feet) horizontally beyond the inside walls of the pool and shall induce unpaved surfaces, as well as poured concrete surfaces and other types of paving. Bonding to perimeter surfaces shall be provided by:
1 - Structural reinforcing steel. Structural reinforcing steel shall be bonded in accordance with 680.26(B)(1)(a) - basically rebar installed in a 12" grid with tie wires and 4 points of connection to the #8 bonding wire.
2 - Alternate means (when no steel reinforcing is present) - At least one minimum 8 AWG BARE solid copper conductor shall be provided - follow the contour of the perimeter of the pool 18 to 24 inches from the inside wall of the pool, 4 to 6 inches below the subgrade.

#2 is used when there is no steel in the deck or the deck is pavers or some other installation which would not use steel reinforcing.

I hope this helps with any confusion I may have created.

 

[dloki]

Two more pictures from the same pool install showing the rebar grid (one side) and the bonding connection (there are 4 total equally spaced around the deck)

 

[cptserious]

This is perfect. Thank you dloki.

How do you suggest I clean out the metal cups? Scruff pad or get a stiff wire disk and use a drill to clean out well?

 

[dloki]

Depending on how corroded they are you may need something more aggressive like a sandpaper cart on a drill. If you use a wire wheel just watch where any wire wiskers that break off may go, you don't want them in the pool.

 

[cptserious]

Thank you again dloki. I'll be cleaning up those cups for the railings and the ladder today and will let you know what happens.

Another question for anyone. If the light that is in the pool is bonded properly to the wire/grid, would that bond the pool water too?

 

[dloki]

Article 680.26(B)(7)(C) Pool Water - an intentional bond of a minimum conductive surface area of 5800 sq mm (9 sq in) shall be installed in contact with the pool water. This bond shall be permitted to consist of parts that required to be bonded in 680.26(B)

Some wet niche light shells have a metal strip (stainless steel usually) in them that is bonded, if it meets the criteria above then it can act as the water bond. I have seen debate about the size because of the wording you could interpret this as 2 sides of the metal strip would both count as surface area so in theory a 1 in by 4.5 in strip would equal 9 sq in however I have seen some inspectors say it needs to be 9 sq in per side because of the way it's mounted with one side against the plastic housing... it can be a grey area so I usually stick with the ladder as the water bond.