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View Full Version : Help! We cant figure out how stray voltage is getting in our pool


helpfast
May 22, 2014, 10:56 AM
I put in a pool last summer and it is has given us a slight sting on fingers since the first week. We have called everyone and no one can tell us how the power is getting in the pool. How can you bond a pool to existing concrete? I think the pools bonding grid isn't correct or we would not feel the sting.
They say power ould be coming in from the ground rod to the light to the pool... bonding should protect us against that.

helpfast
May 22, 2014, 10:58 AM
Also: can anyone tell me where I can find an inspector to tell me if the pool is bonded or not?? I can't seem to get a straight answer on anything concerning this issue.

smoothy
May 22, 2014, 11:03 AM
Hire a licensed Electrician... explain the problem... they should be able to find and fix the problem. This is a very dangerous and serious matter.

Studs ad
May 22, 2014, 12:41 PM
Do you have pumps etc. circulating or cleaning the water in the pool? Are the pumps protected by GFCI breakers? Does the pool have a light? If you are getting shocked, there is definitely a potential difference and or leakage current. If you are standing on the concrete and touch the water and get shocked, they are definitely not at the same potential. If you are at a different potential, then your bonding is not good enough or non-existent.

Newer concrete swimming pools are full of rebar that is bonded to the hilt to maintain equal potentials at all points in the pool. I have experienced in the past a situation where the swimming pool concrete was built before these codes were in place. The owner said that occasionally someone would say they were shocked by touching the surrounding wet cement outside the pool. The pool was fed by natural hot springs, so no pumps etc. were used. I eventually found a sump pump down stream from the pool that was dumping water into the same stream as the water exiting the pool had issues. The sump pump was not protected by a GFCI breaker and the water leading back to the pool was slightly energized when the sump pump kicked on. The concrete around the pool was new with rebar etc. embedded in it and not attached to rebar in the pool if there even is any in a pool this old. The swimming pool had to be at a higher resistance to ground than the newer concrete around it, thus allowing the pool to be at a different potential than the concrete around it. The issue was resolved by replacing the sump pump with a different type and installing a GFCI breaker on the sump pump. The bonding issue will never be fixed until they replace the cement pool and bond its rebar etc. to the rebar of the surrounding concrete. In one training session I had with the engineers from the power company, they explained that it was possible for a person to be swimming in the water not touching anything but the water and the potential between their head and feet could under rare circumstances be enough different to electrocute them. A little far fetched, but bonding and grounding of swimming pools and proper grounding, bonding and GFCI protection of electrical equipment are really critical in a swimming pool. Not something to ignore!

helpfast
May 23, 2014, 07:48 AM
I have hired an electrician. And had the local utlities company came out as well. No one can tell me how the stray is getting in the pool. The entire power is off on the street and it is still there. They think it is backfeeding through my ground rod and getting in through the light. How can we bond the pool to the concrete without ripping out all the concrete? The sting is only felt on a tiny cut if you are touching wet concrete and pool water. The pool is saltwater. Would more grounding rods help?It is so sad to just recently pay so much for a pool and not be able to use it.

helpfast
May 23, 2014, 07:50 AM
Yes we have pumps, heater, saltwater generator, light, slide, diving board. 16 by 32 inground liner.
GFCI protection as well (shouldnt that trip if it got high enough to be electrocuted) the breakers I think are giving me a false sense of protection.

helpfast
May 23, 2014, 08:00 AM
This is so stressful and to have spent so much money on a pool and not be able to use it. No one can seem to help us within our reach. Probably the best thing to do would be to fill it in and to think it was only a year ago we were sooooo excited about our new pool

smoothy
May 23, 2014, 09:16 AM
Maybe find another electrician first... like every other field, they all aren't equally talented.

Studs ad
May 23, 2014, 11:50 AM
I get accused of lengthy answers, but this will be my last. The power company is probably at fault, but unwilling to do what it takes to find it. I had a similar situation a few years ago. I did the necessary assessment and told the home owner they needed to contact the power company because the issue was on their side. They did, the power company spent 3 days checking and finally found the issue on a capacitor bank 2 blocks away from their home. That's all I am going to say.

helpfast
May 23, 2014, 12:06 PM
In your opinion do you think a pool can be correctly bonded and have electricity bleed into the pool backfeeding from the ground rod?
I don't want to tear up concrete and find the pool corectly bonded... :(
And we apprecitate your lengthy answers! WE NEED Help.

Studs ad
May 23, 2014, 12:09 PM
I have to get into a theory discussion, and I don't want to offend those who like short answers, If you want to address me privately I will try explain what is going on. And thank you.

Cat1864
May 23, 2014, 12:50 PM
I have to get into a theory discussion, and I don't want to offend those who like short answers, If you want to address me privately I will try explain what is going on. And thank you.

Please keep all advice on the board.

Thank you.

I have no experience in this subject but would love to read what you think might be happening. It may also help other come up with ideas on what the issue could be.

Studs ad
May 23, 2014, 11:23 PM
I spent the last 8 hours trying to explain how to test and evaluate how to troubleshoot your system. I finally got it worked down to a few simple tests. I wrote up the procedure and the thought process and sent it. I checked your responses and it never showed up. It is past midnight here and I started at about 1 this afternoon. I am not going to re-write it again tonight. There are answers and they will take some time to test out. You will need the assistance of an electrician probably. I am almost positive that there is a fault somewhere that is causing your issue and that the fault originates outside of the area that the power company shut off. To put your mind at ease a little, the problem wasn't there when they installed the pool. Bonding or no bonding the problem appears to have been created since installation. Better bonding may have masked the fault, but it would still be there okay. So assume something changed since installation. Assume that it is outside the boundaries that you turned the power off to. That leaves basically to directions- one is that the fault current is coming in from your water supply. It means that a few things have to be just right, but I know how to test for it. The other is that it is coming through the earth itself and I know how to test for that. I will contact you further at your request. I am not exploring your power system at this time because my evaluation tells me that it most likely didn't come that direction. If the other two directions lead to a dead end we will go down this road later. Thanks for trusting me a little. I get a little frustrated sometimes. Respect is always earned. Friendship I appreciate. A challenge I enjoy. You have given me an opportunity for all the above.
Thank you!

Studs ad
May 27, 2014, 09:47 PM
I spent the last 8 hours trying to explain how to test and evaluate how to troubleshoot your system. I finally got it worked down to a few simple tests. I wrote up the procedure and the thought process and sent it. I checked your responses and it never showed up. It is past midnight here and I started at about 1 this afternoon. I am not going to re-write it again tonight. There are answers and they will take some time to test out. You will need the assistance of an electrician probably. I am almost positive that there is a fault somewhere that is causing your issue and that the fault originates outside of the area that the power company shut off. To put your mind at ease a little, the problem wasn't there when they installed the pool. Bonding or no bonding the problem appears to have been created since installation. Better bonding may have masked the fault, but it would still be there okay. So assume something changed since installation. Assume that it is outside the boundaries that you turned the power off to. That leaves basically to directions- one is that the fault current is coming in from your water supply. It means that a few things have to be just right, but I know how to test for it. The other is that it is coming through the earth itself and I know how to test for that. I will contact you further at your request. I am not exploring your power system at this time because my evaluation tells me that it most likely didn't come that direction. If the other two directions lead to a dead end we will go down this road later. Thanks for trusting me a little. I get a little frustrated sometimes. Respect is always earned. Friendship I appreciate. A challenge I enjoy. You have given me an opportunity for all the above.
Thank you!

Are you ready to try something?