2 volts in pool, bond wire, grounding rods

roger said:
What's being described actually sounds more like a POCO issue.
As far as capable EC's, it make take some searching to find one that is. Pools are not for DIYers
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I think Roger is correct on this being a POCO issue. All these other occurrences at your home and the neighbors are not coincidental.
Still, DO NOT USE THE POOL!!!!
 
My best guess at this time that the utility neutral voltage is elevated relative to local earth. The pool deck has a proper bonding grid and is connected to the utility neutral, but that the pool shell, pool water, and soil surrounding the pool deck are at the local earth voltage.

SunTitan said:
Its vinyl lined with concrete steps and tanning ledge. The bottom is Portland and walls are composite. What I'm getting here is to get a competent pool electrician in here asap and that even if there is stray or leaking underground volatge, or a neutral backfeed from tbe utility, the bond should be protecting is from that? The city inspector did come out and perform a bond inspection and passed it. Also adding that this pool. Build was completed only 2 month ago.
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Is there any metal in the pool shell such as rebar? If there was nothing to bond in the shell, then the pool contractor may have done all the required bonding. It may be that given local soil conditions that the minimum required bonding is not sufficient to fully equipotential bond the pool.

IMHO you have 2 issues to chase down: the cause of the voltage difference between bonded structures and local soil and the lack of bonding between pool deck and pool shell. As I said, the lack of bonding might be because there is nothing to bond.
 
winnie said:
My best guess at this time that the utility neutral voltage is elevated relative to local earth. The pool deck has a proper bonding grid and is connected to the utility neutral, but that the pool shell, pool water, and soil surrounding the pool deck are at the local earth voltage.



Is there any metal in the pool shell such as rebar? If there was nothing to bond in the shell, then the pool contractor may have done all the required bonding. It may be that given local soil conditions that the minimum required bonding is not sufficient to fully equipotential bond the pool.

IMHO you have 2 issues to chase down: the cause of the voltage difference between bonded structures and local soil and the lack of bonding between pool deck and pool shell. As I said, the lack of bonding might be because there is nothing to bond.
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Those steps and the sun shelf/tanning ledge may have reinforcement (really should) in it which must be bonded. Hopefully the electrician picked up on that.
 
SunTitan said:
... Checked by the house under the meter - grounded to the wire on the ground rods and red probe in the dirt, getting 1.8. ...
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The job of the pool bonding is to raise the voltage of the pool water and every conductive object within in reach of the water to that voltage. If you are seeing that voltage between parts of the pool, pool equipment, or perimeter deck, the pool bonding was not correctly installed.
Voltage between the electrical grounding system and remote earth is common and often called neutral to earth voltage. It is a result of the voltage drops on the service neutral and on the utility primary neutral if the transformer that supplies power to the service is connected line to neutral on the primary side.
 
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Mystic Pools said:
I think Roger is correct on this being a POCO issue.
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Proper bonding during pool installation should make POCO issues a non issue - this is a major reason they have those equipotential bonding rules to begin with as it is difficult to maintain zero neutral to earth voltage with MGN distribution. A couple volts or so of NEV is pretty common on MGN supplied systems. There has to be a hole in the bonding somewhere that allows for potential differences. Something like this could be one possible scenario:
winnie said:
My best guess at this time that the utility neutral voltage is elevated relative to local earth. The pool deck has a proper bonding grid and is connected to the utility neutral, but that the pool shell, pool water, and soil surrounding the pool deck are at the local earth voltage.
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Some measuring between pool water and conductive objects in or within reach of the pool may help determine what is bonded and what is not.
 
Sounds like water is not bonded. If liner is non conductive, a water bond fitting installed on plumbing pvc supplying pool water may alleviate the problem as long as deck and pump or properly bonded. Consult a qualified EC familiar with pools.
 
Greentagger said:
Sounds like water is not bonded. If liner is non conductive, a water bond fitting installed on plumbing pvc supplying pool water may alleviate the problem as long as deck and pump or properly bonded. Consult a qualified EC familiar with pools.
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Maybe. Though all it takes is say a metal ladder or some other metal component that is bonded to also be in contact with the water and the water is bonded. Pool pump or heater is also a potential place where water may inherently be bonded.
 
SunTitan said:
This is the issue. The pool electrician that was used for install claims everything is fine and that a neutral must be backfeeding to the ground. Claims bonding is fine. Another electrician recommended a "shield" around the pool. The most recent electrician says he believes that there is voltage leaking underground and it's an EMC problem. If the bonding is bad, that would mean that the concrete presumably needs to be busted up? Would the shield be a safe alternative to that?
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Regardless of the voltage source and it could even be as high as 120V, if the Equipotential bonding is correct, no one would be getting shocked.

What is happening we ask question like How long has the pool been in place? I've seen pool installers use the wrong terminations not listed for DB or concrete that had corroded. Water bonding too can over time corrode to the point of being ineffective. Also seen work done after installation that compromised the bonding.
Have also seen many times where a new pool was not installed correctly AFA the Equipotential bonding, work being done but the "cheapest" installer or a GC that should have never been involved with pool installation as they had no knowledge of the bonding procedures. Also seen where a product or device that was originally planned and spec out that got substituted to "get the job done" and compromised the EPB.
Recommend get someone who specializes in pool bonding repair, this situation can get deadly.

Not sure what sort of "shield" you might be talking about. There is no substitute or short-cut to doing it correctly, this can be deadly. A very methodical approach to testing the bonding will tell a specialist where the bonding went wrong.

A utility source as suggest while likely given some of the comments wouldn't matter if the bonding is correct. If If utility NEV is the issue causing the voltage, source direction can be seen by a minuet difference of readings one side of pool compared to the other side. But the NEV will vary depending on community loads at any given moment in time.

Some of the readings being reported look like it could be a neighbor with a poor neutral connection. Seen one pool that had similar readings that it turned out to be the POCO pad mount transformer had a corroded neutral. Repair got rid of the voltage but still needed to fix the bonding for when another issue occurs that may be worse.
 
I had a job recently where the customer was getting a tingle from the hand rail. It was not what I was there to repair, but I looked it over for him. I found about 1.5 volts between the handrail and house ground. No bond wire at the pump. Killed the main breaker and the voltage remained, so it is coming from outside. I told him I wouldn't use the pool, but he's not letting his pool sit idle for a fews volts. Oh well, at least have a designated driver outside of the pool ready to save lives if whatever is sending that 1.5 volts decides to suddenly send more.
 
kwired said:
Maybe. Though all it takes is say a metal ladder or some other metal component that is bonded to also be in contact with the water and the water is bonded. Pool pump or heater is also a potential place where water may inherently be bonded.
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Maybe. A ladder at one end bonded to the rest of the deck EPD you will have a difference in water potential at far end away from the ladder. Somewhere the bonding is failing in order to get a difference of potential. Seen where a non-conductive ladder was spec. so no bonding was provided at the ladder cup, then a metal ladder actually got used.
 
Get the EMC involved.
Show them neighbors are having same issue.
Is this an overhead service and all neighbors off the same transformer or is it underground?

We had a pool that was shocking people.
Come to find out the concentric neutral on our old XLPE unjacketed cable had deteriorated. We ran copper from one transformer to the other to bridge the bad neutral on this span of cable.

Had another that had voltage everywhere- cable vision guy disconnected his cable and was sparking across the ground wire from the Meterbase. Come to find out the transformer had a deteriorated neutral bond at the center bushing.
 
Fred B said:
Water bonding too can over time corrode to the point of being ineffective. Also seen work done after installation that compromised the bonding.
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I prefer the inline water bonding fitting over the skimmer body type. They most certainly can corrode quickly as most pool owners do not maintain their water chemistry properly. The skimmer type mounted water bond is pretty much in accessible to replace for a concrete pool as the skimmer is encased in concrete. Vinyl or fiberglass pools skimmers are accessible.
Landscapers planting plants, irrigation contractors or fence contractors will and have damaged bond wires when doing their work. The smart pool contractors will consider this possibility when they are planning their project and make considerations.
 
Hv&Lv said:
Get the EMC involved.
Show them neighbors are having same issue.
Is this an overhead service and all neighbors off the same transformer or is it underground?

We had a pool that was shocking people.
Come to find out the concentric neutral on our old XLPE unjacketed cable had deteriorated. We ran copper from one transformer to the other to bridge the bad neutral on this span of cable.

Had another that had voltage everywhere- cable vision guy disconnected his cable and was sparking across the ground wire from the Meterbase. Come to find out the transformer had a deteriorated neutral bond at the center bushing.
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Proper bonding in a pool should still equalized touch potential for users though, things happen on service and/or distribution system that can cause neutral to earth voltage to rise at the service entrance, this is a major reason the bonding rules in art 680 are there. In my experiences a volt or two from service neutral to isolated earth probe is almost always going to have at least a volt or two on it, even if you shut your service disconnect off. Most people will feel that if they are placed across it while immersed in a pool. Proper bonding puts them at same potential as everything they can touch.
 
SunTitan said:
I've been about everywhere else with no luck. Around 2 weeks ago my wife called and said that the newly installed in-ground pool was "zapping them". I check voltage and read 1.8-2 volts with the power prod in the water and ground on the deck. Checked by the house under the meter - grounded to the wire on the ground rods and red probe in the dirt, getting 1.8. Checked one neighbor an out 100 yards away, they have 1.8 at their meter on the ground, while the other neighbor shows 4.6. Had two new ground d rods installed today, no change. If the bonding wire is removed from the pool pump, voltage drops to almost nothing in the pool. We've killed every breaker while watching the water voltage - pool sub panel, main panel, and every single breaker in the house - voltage remains. I did install a ceiling fan on the back patio recently - any chance that's the culprit before I take it down to check? Would that affect the neighbors? From what I'm reading as response to others, I need to get EMC involved. We've had a good bit of weather and storms lately and this seems to be a rather sudden thing. Also, on the same day the pool shocked them, my doorbell transformer went out and the garage door went nuts for a few hours. House built Sept of 2023. Help me, smart people.
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I would love to know what the fix is. I have the exact same problem. 1.9v at the water, disconnect the bonding wire from pump and voltage goes away. Walton EMC came out this morning and said all looked good on their end. From the bad storm we had on the 7th I lost multiple light bulbs throughout the house (built 2019) as well as my internet router and direct TV console both fried. Did not use the pool again till last Thursday where my kids and myself felt the tingling sensation from touching the pools edge. Electricians are saying it’s on EMC’s side and EMC is saying all is good and install grounding rods and should fix the issue. If I’m not mistaken you may be in the same area as myself and use some of the same contractors. Please let me know if you get any answers. Brand new pool is sitting idle for me.
 
PJ31385 said:
I would love to know what the fix is. I have the exact same problem. 1.9v at the water, disconnect the bonding wire from pump and voltage goes away. Walton EMC came out this morning and said all looked good on their end. From the bad storm we had on the 7th I lost multiple light bulbs throughout the house (built 2019) as well as my internet router and direct TV console both fried. Did not use the pool again till last Thursday where my kids and myself felt the tingling sensation from touching the pools edge. Electricians are saying it’s on EMC’s side and EMC is saying all is good and install grounding rods and should fix the issue. If I’m not mistaken you may be in the same area as myself and use some of the same contractors. Please let me know if you get any answers. Brand new pool is sitting idle for me.
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PM each other.
 
PJ31385 said:
Electricians are saying it’s on EMC’s side and EMC is saying all is good and install grounding rods and should fix the issue.
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Ground rods is not the solution. It only fixes such problems in the vicinity of the rod, and depending on soil conditions that vicinity may be pretty limited area around the rod as in you might see similar voltage issue as you originally were trying to fix from said rod to an earth probe just a couple feet away.

If this is portable pool or above ground pool, my best suggestion is to have a non conductive deck around the pool and that will likely eliminate a lot of possible issues. In the ground pool or pool on concrete slabs should have bonded reinforcing steel in them to create a equipotential grid in the slab or pool walls.

One of the bigger shock risks that is not due to equipment malfunctions is often at the perimeter of the pool as you are inside the pool which is typically going to be at same potential as the grounded service conductor as the EGC ultimately ties to that point and you may be touching something outside the pool that is at true earth potential.

With equipotential bonding we don't care what neutral to earth voltage is, nor do we necessarily want to achieve getting everything to earth potential. We are trying to keep everything pool users can contact while using the pool all at the same potential whether it is same as earth or even if it is hundreds of volts to earth. Birds on overhead power lines are sitting there at possibly thousands of volts to earth, but are not able to touch anything at a different potential and therefore are safe from being electrocuted when on the line. Similar concept with equipotential bonding at pool installations, if you touch something at same potential as you already are nothing happens.
 
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