Stray voltage around swimming pools

[bigdee]

Re: Stray voltage around swimming pools

Wow man! You have a problem not the NEC.

Seriously have the problem checked by a pro.

I am a pro that is why I want to share this with people(IEEE) that have the knowledge to discuss further. A pool that shocks is a serious subject that the NEC needs to review. There has been a case where a child drowned because the small electrical shock was enough to cause paralysis.

 

[Keepi time]

Re: Stray voltage around swimming pools

By removing the ground wire you essentially made it possible for whoever is in the pool to become part of a short in any of the systems associated to your pool. It would be like cutting the ground off an extension cord and using it to run the motor that recycles the water in your pool. I have wired many pools and boat lifts. Anytime water and electricity is involved there needs to be a ground. Had a homeowner who felt a tingling sensation when she was in her pool, ended up exactly what you are doing. There was no ground. If there is a short in your motor, it is going to find ground somewhere. You don't want to become part of that short. Drive another ground rod at your meter base and connect the two with a solid copper wire, no breaks. That should take care of your problem. Also if you are getting readings to ground from the water in your pool, there is stray current coming from somewhere, I would ohm out every wire associated with that pool before I got back in it. The NEC codes are made from insurance claims. That's why they are there. I agree that not all make sense, but grounding and bonding anything associated with a pool makes sense to me. IMHO

 

[bigdee]

Re: Stray voltage around swimming pools

By removing the ground wire you essentially made it possible for whoever is in the pool to become part of a short in any of the systems associated to your pool. It would be like cutting the ground off an extension cord and using it to run the motor that recycles the water in your pool. I have wired many pools and boat lifts. Anytime water and electricity is involved there needs to be a ground. Had a homeowner who felt a tingling sensation when she was in her pool, ended up exactly what you are doing. There was no ground. If there is a short in your motor, it is going to find ground somewhere. You don't want to become part of that short. Drive another ground rod at your meter base and connect the two with a solid copper wire, no breaks. That should take care of your problem. Also if you are getting readings to ground from the water in your pool, there is stray current coming from somewhere, I would ohm out every wire associated with that pool before I got back in it. The NEC codes are made from insurance claims. That's why they are there. I agree that not all make sense, but grounding and bonding anything associated with a pool makes sense to me. IMHO

I appreciate your reply Keepi time, I have only removed the system ground from the branch circuit that feeds the GFCI that supplies service for the pool equipment. The pump,SWG and all metal components are bonded together. IF there is a ground fault in the pump motor it will trip the GFCI......I realize it my not trip a non-GFCI breaker because the impedance in the independent bonding may be too high to instil enough current to do so. I have tried all the stray voltage remedies to no avail and while it may not be dangerous according to the NEC,it is extremely unpleasant for anyone using my pool.

 

[Fishing Dude too]

Re: Stray voltage around swimming pools

What you are not listening to or seem to not. If the ground is dried out the voltage will take the path of least resistance hence for the the shock in water, it goes to water. Check it out had a friend of mine loose her mother because o a faulty ground on a water heater.

 

[jimbo_jwc]

Re: Stray voltage around swimming pools

Megger you pumps , lights ,extension cords , all burried lines , a nick in insulation break down thru a load to ground can put the potential there to ground and still run because it won't blow a breaker because neutral is path of least resistance ??

 

[bigdee]

Re: Stray voltage around swimming pools

What you are not listening to or seem to not. If the ground is dried out the voltage will take the path of least resistance hence for the the shock in water, it goes to water. Check it out had a friend of mine loose her mother because o a faulty ground on a water heater.

The GFCI will trip if any ground fault is detected. I know NEC requires that the pump housing to tied to system ground but the pool bonding grid is also connected to the pump,hence lies the problem....The pool is connected to the power companies grounded but CURRENT carrying 13k volt conductor which IS putting annoying stray voltage on my pool deck. I have a choice to leave as is and shock my grandchildren every-time they get out of the pool or do as I have done. Just as a test I have plugged an extension cord into the pool outlet and tossed the other end into the pool and it tripped the GFCI instantly. I also purposely touched the live conductor on the pump to the pump housing,pool ladders, coping and wet concrete deck and the breaker tripped in each case. Just to add some safety redundancy I will also put a GFCI in series with the current GFCI outlet. The root cause of the stray voltage is voltage gradients in the soil itself....I can drive 2 metal stakes 6 feet apart in my yard (well away from pool) and measure 2.4 volts between them.

 

[Fishing Dude too]

Re: Stray voltage around swimming pools

You have not said if area is dry, the ground around ytou house dries out first and deeper. The stray voltage in the yard coud b a DC effect voltage due to asids in the ground. Take a lemon put 2 leads into it and check voltage.

 

[bigdee]

Re: Stray voltage around swimming pools

You have not said if area is dry, the ground around ytou house dries out first and deeper. The stray voltage in the yard coud b a DC effect voltage due to asids in the ground. Take a lemon put 2 leads into it and check voltage.

No,it is AC at 60Hz. I have had this situation for 29 years,my children used to laugh about it and dare each other about who could hold onto the handrail the longest! My grand-babies ain't that tough yet. There are other pools in my town that have the same problem.....not a pleasant way to swim! My pool is now shock free and IMO safer.

 

[rbh]

Re: Stray voltage around swimming pools

So just to say this again (I have work as both a power and tel lineman over the last 26 years) you could have primary power leaking either from the insulator or the transformer down the pole to ground.
(I have drilled into a pole more than once and got zapped due to poor insulators or transformers)
Or for that matter you may have the best ground around for miles and its bleading all the induction off at your pole.
(if you have a neutral under the primary)

 

[scoyt]

Re: Stray voltage around swimming pools

Pour some water on the ground rod, hook everything up as you had it before. I bet your ground rod is too dry to ground properly. It can only ground through moisture. I don't know how dry it has been there, but I would be willing to bet that is the problem.

 

[rbh]

Re: Stray voltage around swimming pools

Pour some water on the ground rod, hook everything up as you had it before. I bet your ground rod is too dry to ground properly. It can only ground through moisture. I don't know how dry it has been there, but I would be willing to bet that is the problem.

Hey forgot about that one, (we used to have to meager all the grounds in dry areas to make sure they were good enough.
Yup your grounds around the pool are better than the pole (easiest path to ground)

 

[bigdee]

Re: Stray voltage around swimming pools

Hey forgot about that one, (we used to have to meager all the grounds in dry areas to make sure they were good enough.
Yup your grounds around the pool are better than the pole (easiest path to ground)

rbh is right on target with this......people tend to forget that the power companies use the earth as a return path. I have measured from the #6 ground wire on the utility pole to a metal stake 10 feet away and recorded several volts.......gradients confirmed.

 

[Thalasso]

Re: Stray voltage around swimming pools

My electric company also now requires two ground wires at the meter socket just for said reason. Girlfreinds pool did the same thing until i put a ground rod in just for the pump.

 

[Keepi time]

Re: Stray voltage around swimming pools

http://www.mikeholt.com/strayVoltageVideo.php. Check this video out. Also look at this forum and search pools. May give you some insight.

 

[bigdee]

Re: Stray voltage around swimming pools

http://www.mikeholt.com/strayVoltageVideo.php. Check this video out. Also look at this forum and search pools. May give you some insight.

In simple layman terms....the power grid is the source of the problem and it is using the pool to drain it's unpredictable fault currents. When a person,such as my grandchild is standing in the pool and touches a hand rail (or any other object that the NEC REQUIRES you to bond back to the utilities system ground) he effectively uses his body as a path for this stray voltage to find the same potential. I have 2 ground rods at the meter and the power company has a 10 foot ground at their service drop. Stray voltages are a real problem especially around farm animals and the NEC has done little to address the problem. This problem can be eliminated IMO be relying on GFCIs and bonding but isolating the bonding system from service ground. No person or jurisdiction has been able to explain the safety theory of the current mandate. NEC claims it is required to keep everything at the same potential which in fact it can create a difference in potential as in stray voltage.

 

[Keepi time]

Re: Stray voltage around swimming pools

Have you disconnected the neutral coming from the service drop and checked from the neutral to ground to make sure it is coming from the utlity company?

 

[bigdee]

Re: Stray voltage around swimming pools

Have you disconnected the neutral coming from the service drop and checked from the neutral to ground to make sure it is coming from the utlity company?

I did disconnect the neutral/ground at service and stray voltage went away. I even disconnected both "hot" service conductors and left neutral/ground connected and the stray voltage was present at pool. This is definitely a classic stray voltage case. Stray voltage is caused by primary and/or secondary return current because these currents
flow through the impedance of the intended return pathway. I see no reason why a GFCI cannot be used as a salvation to this problem......a system ground is not needed for a GFCI to function properly.

 

[NSBCraig]

Re: Stray voltage around swimming pools

If the power grid is dumping power threw your pool to ground, your having a grounding problem... taking the pool out of the equation isn't changing that now is it?

The way I see it you have narrowed it down to- 1 you need the power company to fix their equipment or 2 you need to fix your grounding system.

There are millions of pools hooked up as per the NEC and no one's complaining about them. You said someone else in your town has the same issue, which leads me to think that it's either they are having the same issue with the power company as you or it has to do with the make up of the ground where you live.

Have you contacted the power company about it?

 

[bigdee]

Re: Stray voltage around swimming pools

Have you contacted the power company about it?

Yes, and they agree that it is stray voltage created by gradients in the equipotential bonding grid caused by the NEC's requirement to bond to their neutral. They, along with the NEC claim it is an annoyance (because people can feel the shock of 2 or 4 volts while standing in water but it is not a safety issue and the NEC also says it is not an issue as long as the difference in voltage potential stays below 10 volts. I say hogwash and if you swam in my pool before I made these changes you would agree. WHY would one have to suffer this discomfort in order to satisfy the archaic NEC?
With the advance of technology (GFCIs) this situation can be and should be eliminated by the NEC. A NEUTRAL IS A LIVE CURRENT CARRYING conductor and as verified by the utility company is tied via a bonding jumper on the transformer to the primary 13,000 volt primary. That grounded 13k volt conductor is what was tied to my pool.

 

[bigdee]

Re: Stray voltage around swimming pools

Thanks to everyone that replied. I realize this is probably not the perfect topic for this forum but I was hoping to find someone that had a similar problem with stray voltage. This problem is non-existent in countries that DO not use grounded neutral systems. I have had to remove the ground wire in my panel that feeds the branch circuit to get rid of the uncomfortable stray voltage in my pool. I feel that this issue of requiring a pool's bonding system to be connected to the house system ground should be challenged.......electrical theory does not support how this would make a pool safer.