# Measuring pool water voltage



## faber307 (Jan 22, 2007)

Been gone for awhile, nice to see you are all still here.

I've got a situation where I was contacted by a pool supply owner about an inground pool installation he sold.

The buyer hired his own electrician. The buyer and the pool man think there has been stray voltage in the pool. They wanted an unbiased opinion / inspection.

The wet niche fixture was an LED unit. I met with the pool installer, pool salesman, and homeowner this afternoon. During this meeting the pool installer told me that the trim ring was not put on before the fixture cord was pulled into the conduit. The splice box at poolside for the fixture was not installed. In order to get the trim ring on, the fixture would have to be removed and factory cord pulled out, ring installed and cord pulled back in. The electrician said that this could not be done. 

The pvc pipe feeding the fixture stubbed into a sheet rock wall then the cord was ran into a nail on box for the light switch. He explained that the cord was inbedded in spray foam.

The electrician took the Led light apart to slide the trim ring over, then re-assembled the fixture.

This was a year ago.

The ladder is corroding badly
They pointed out a couple screws on the skimmer that appear to be discolored and tracking? like an arc. I'm not buying that one yet.

The homeowner complains of above normal hair loss, and thinks it's attributed to somthing wrong with the pool.

The pool supplier told me how the homeowner was bragging about what a good deal he received on wiring his pool and pool house.

The homeowner, I can tell is ready to sue someone. He's leaning toward the pool installer or the electrician.

So here is what I witnessed today.

No improper bonding of the pool grid to electrical panel (this is what I expected to find, grid connected to service ground)

Fixture is shot, needs replaced.
No fixture splice box.

Fixture circuit is not dedicated, fed from romex at switch box, circuit feeds other outlets on pool house wall.

Fixture is fed from ground fault receptacle

Pump case has bare #10 ground going into concrete instead of #8 along with water lines for in floor heat system.

Homeowner says ladder pockets were attached to steel re inforceing bars.

cannot tell if light fixture housing is or isn't connected to grid

This job was inspected and the homeowner says the inspector used a ohm meter to check grounding.

PVC conduit feeding fixture runs about 25' to exterior building wall, pool installer says they were losing alot of water and he sealed the conduit behind the fixture. It has slowed considerably.

The pool supplier is supplying a replacement light fixture.
The original electrician is installing the light next week.
I am asked to go back and measure for voltage on the pool water after it is filled.

I have never done this.
Am I right that I would run a wire from the pool room load center, drop it in the water then measure from the wire to the load center ground?

This sub panel has 4 wires running to it and the neutral is separate from the ground.

What am I missing?
How do I measure the pool water for voltage?

Looking to pull from other's past experience with somthing similar.


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## brian john (Mar 11, 2007)

1. WHERE HAVE YOU BEEN, I have been wondering about you.
2. I need to think on this and will.
3. But for starters.

NOT NECESSARILY IN ORDER.

I would test the exposed metallic portions of the pool to the neutral ground bond connection.

Measure for ground current on the neutral ground bond jumper, you may have to install a temporary jumper.

Check all neutrals for ground connections downstream from the panel (megger)

Do a zero sequence test on the panel feeder.

If you do measure voltage from the pool turn off all house power and test again.

Measure for current on the water piping ground connection (if it exist)


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## Bkessler (Feb 14, 2007)

I had one not to long ago where people were feeling stay voltage around the pool when they touch the fence or the support beams for the deck above. It turned out to be a gutter nail through a romex on the side of the house.


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## frenchelectrican (Mar 15, 2007)

I have a question or two but do the 120 v pool luminaire do have isolated transformer?? [ i know that part with 12 volt verison but not sure with 120 because i havent done one for a while ]

also IIRC the wet niche luminiares the housing ground lug useally are exteral of housing the only way to get in there is bust open the pool wall or dig in from above that will be pain in the ase.

but for rest of testing Brian John pretty much nail in what he expaining on this one 


Merci, Marc


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## faber307 (Jan 22, 2007)

brian john said:


> 1. WHERE HAVE YOU BEEN, I have been wondering about you.
> 2. I need to think on this and will.
> 3. But for starters.
> 
> ...


 
Life picked up speed, only been on the computer for running the business.
It seems to be getting back to normal now. Like I said, glad you're still here. This site is a very valuable information tool. I look forward to catching up and reading all these new posts. Service work for us has been surprisingly steady and consistant. Last year was great, and there has been no end in site so far this year. 

God bless America.


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## brian john (Mar 11, 2007)

NOT NECESSARILY IN ORDER.

I would test the exposed metallic portions of the pool to the neutral ground bond connection.
The pool room panel is 4 wire with no bond, please explain what potential voltage readings this would provide vs. a test to ground then a test to neutral

You are looking for a source of voltage any metallic structure in the pool may have the possibility of being the source or there may be multiple sources. Trying to get a measurement form water may be difficult.
*Back at the main service.*
Is the pool room panel in a separate building.


Measure for ground current on the neutral ground bond jumper, you may have to install a temporary jumper.
If I install this jumper temporarily, wouldn't I EXPECT to measure current going back on the ground wire to house panel?

Do this at the house panel


Check all neutrals for ground connections downstream from the panel (megger)
unplug all equipment, turn off all light switches, trip all GFI recepts, then measure with megger at 250v?

YES. ALL in the house and pool panel


Do a zero sequence test on the panel feeder.
explain please, does this mean test water voltage with only one circuit at a time, or variations of circuits on?

Use a current clamp around all conductors 2 hots 1 neutral at the pool panel and house panel. READING should be "0", I use a low current flexible CT (30 amp max). When are you going to do this test?
 I can loan a CT if you need. BUT we need to move fast if you want to borrow.


If you do measure voltage from the pool turn off all house power and test again.

Measure for current on the water piping ground connection (if it exist).


*Is this house on a common transformer with other residences/facilities, do they share metallic water piping?*


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## faber307 (Jan 22, 2007)

brian john said:


> NOT NECESSARILY IN ORDER.
> 
> I would test the exposed metallic portions of the pool to the neutral ground bond connection.
> The pool room panel is 4 wire with no bond, please explain what potential voltage readings this would provide vs. a test to ground then a test to neutral
> ...


No shared metallic piping, very rural area.

This will help to make an excellent testing checklist.
I will forward what I find. This is scheduled for next thursday.


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## faber307 (Jan 22, 2007)

frenchelectrican said:


> I have a question or two but do the 120 v pool luminaire do have isolated transformer?? [ i know that part with 12 volt verison but not sure with 120 because i havent done one for a while ]
> 
> 
> 
> ...


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## leland (Dec 28, 2007)

Tab, Grab the code book and read up a little on pools. This will help to tie it together for you.

Bonds (of metal parts) are crucial for the pools to keep every thing equal,even non electrical parts.


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## faber307 (Jan 22, 2007)

Oh I've read on the install of the pool, 
My questions are on testing for stray voltage now that it is installed.
This pool is inground concrete. The customer wants me to measure for voltage on the pool water once it is filled.


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## leland (Dec 28, 2007)

The others have you on the right path. I have never looked for stray voltage yet on a pool.
i would think some leakage and a bad/no/existant bond (big leap huh?)

This is part of the reason the code asks for the water to be bonded.

680.26(B) and 680.26(C) (2008NEC)

Someone (part of a CMP)once told me that most drownings are from disoriantation from stray Vol. and this is the cure.
I have not read or seen anything to back this up.


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## macmikeman (Jan 23, 2007)

Tab, reading your first post about the cord from the light getting imbedded into insulation and connected to a non mettalic switch box, and the number 10 bonding conductor business, tells me there are multiple screw ups with the original install that ought to get fixed. They may have nothing to do with the suspected "stray voltage problem" if there is one, but with the cord being used in a chapter 3 manner is enough to raise caution antenna's. Make sure to point out any code violations you find, unless you carry errors and omissions insurance riders on your liability policy. Ask any forsenic consultant about providing third party checkouts on potentially defective electrical installs and you will get a concurance about this. Measuring for voltage potentials between different parts of the pool structure that is supposed to be bonded together is a more correct way to attack this, cause if the pool is properly bonded, then stray currents or not, the pool is in the earth, and should be at the same potential as the earth is, so therefore even if the potential of the surrounding earth is raised by some stray current, the whole pool and grid should also raise to that potential. Its when different conductive surfaces of a pool are at dissimilar potentials that stray currents can become a problem or a lethal problem. Therefore I would check to ensure that the pool bonding is correct. Sounds like it isn't.


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## Romexking (Jan 28, 2008)

As Macmikeman wrote, there are numerous things wrong with this installation. I would examine the entire installation beginning with where the feeder begins. From there check the bonding (what you can see) and then check the outlet and lighting wiring. Since you say that you are to check the pool water voltage when the pool is filled, why don't you get over there and check/repair the wet niche lighting fixture while the pool water is low. I would make them lower it below the level of the niche. There will be a bonding/grounding terminal in the niche that should be encapsulated with a potting compound...I'm sure that it is not. Also, of course, spray foam is not the proper method of sealing the light fixture conduit. 

As for the "voltage" of the water, you could take a measurement from the motor housing/bondling lug to each and every metal object within 5' of the pool wall. Going from the main panel will not necessarily tell you what you need to know. The pool is not required to be bonded to that panel, only to the water circulating equipment.

I would also call the AHJ and get a copy of that permit and inspection! 

keep us posted on what you find.

Rich


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## 220/221 (Sep 25, 2007)

I was going to say "ask Brianjohn" but he was the first to reply.

Don't know what to add except I once had so much voltage in the pool that I could read it with a no contact tester. The pool guy felt it while adjusting the float/fill. Yikes.

Loose pool light neutral.


The factory cord was encased in foam? You need to have an accessible brass pool light jbox here. The lights DO need to be replaced at some point ya know:jester:


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## Bkessler (Feb 14, 2007)

has the circuit were the fault is been identified, or do you know for sure it's the pool light?


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## brian john (Mar 11, 2007)

tab:

I often do investigations of items, facilities and issues I have little knowledge of, but whether I am knowledgable or not what I do is the following. 
1. A COMPLETE visually first, your eyes are you best tools.
2. Keep a written list of everything no matter how small, if this ends up in court notes will be IMPORTANT. NEC complaince no matter involved in the issue or not is pertinent to your investigation.
3. Do not fix anything till you have completed the investigation, though I will sometimes lift connections to see if it clears the issue, putting everything back as I found it. Usually you are there to investigate not fix, that is an issue between the HO, GC and EC. Note any temporary fixes you made.
4. If you megger or test anything use a form with company letter head. WRITE IT DOWN.

If I think of more I will post.


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## frenchelectrican (Mar 15, 2007)

Just a thought .,, why not take a veido of the whole event when you doing the testing because sometime with veido it will show what is going on [ simuair idea with photos ] and that way you can doucment all at once with veido.


Merci, Marc


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## leland (Dec 28, 2007)

I would also call the AHJ and get a copy of that permit and inspection! 

keep us posted on what you find.

Rich


Excelent Idea!!! No need to explain.


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## brian john (Mar 11, 2007)

> I would also call the AHJ and get a copy of that permit and inspection!


In 37 years of trouble shooting and testing, I have never had a situation where involving the AHJ benefited in anyway, If anything I would think they would complicate the issue.

When you (at least me)are trying to resolve an issue I want no body hanging around trying to think of what the issue might be, I'll resolve the issue, just let me think.


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## Romexking (Jan 28, 2008)

The point of securing the permit and inspection record it to determine that it actually had a permit and was actually inspected. It certainly doesn't change the outcome, but it validates the owner's assertations that it was done by a "professional". The inspector holds almost no liability even if it was wired bass ackwards, so it's not about holding them accountable.


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## faber307 (Jan 22, 2007)

Bkessler said:


> has the circuit were the fault is been identified, or do you know for sure it's the pool light?


I'm not sure of anything at this point.
When I was there, the pool was drained. I met with the homeowner, pool installer, and pool salesman.

The whole meeting revolved around who took the sealed LED fixture apart in the first place because the cord was run up the conduit and into the exterior pool room wall without running through the fixture trim ring.

The pool installer said the EC took it apart and that he couldn't believe that he did it!

The homeowner says the EC swears the pool installer took it apart.

anyway, I did a visual inspection, they told me the EC was replaceing the fixture. I told them I would return when the pool was filled.

And yes Brian John, I do not intend on actually fixing anything. Just trying to find the problem if there is one when I return.

I appeciate all the input men.
That's why I love this site.


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## leland (Dec 28, 2007)

RED FLAG!! "pool installer, and pool salesman.".

RED FLAG!! "The whole meeting revolved around who took the sealed LED fixture apart in the first place because the cord was run up the conduit and into the exterior pool room wall without running through the fixture trim ring."

RED FLAG!! "The pool installer said the EC took it apart and that he couldn't believe that he did it!

The homeowner says the EC swears the pool installer took it apart."

VERY SMART!! "anyway, I did a visual inspection, they told me the EC was replaceing the fixture. I told them I would return when the pool was filled.

And yes Brian John, I do not intend on actually fixing anything. Just trying to find the problem if there is one when I return.

I appeciate all the input men.
That's why I love this site."

Bring a camera, (one with film) not digital or both. Courts /lawyers can easily and have claimed "doctoring" of (edit) digital pictures.

FYI! Best of luck.


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## brian john (Mar 11, 2007)

> Bring a camera, (one with film) not digital or both. Courts /lawyers can easily and have claimed "doctoring" of (edit) digital pictures.


Not true, I develop film and we doctor pictures all the time, the terms utilized in Photoshop, originated in the film industry, burning, dodging, cropping. Any questions about doctoring either film or digital can be resolved by an expert. 

Oh and I have worked as an expert witness all the photo's utilized in the latest cases were digital. High quality digital (and maybe inexpensive cameras) capture Metadata, this tells what is done with the photo...


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## faber307 (Jan 22, 2007)

No testing yet, Pool man called last week and the water truck froze up!
supposed to get a call this week.


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## HighWirey (Sep 17, 2007)

Leland wrote:
"Bring a camera, (one with film) not digital or both. Courts /lawyers can easily and have claimed "doctoring" of (edit) digital pictures."

Brian wrote:
"Not true, I develop film and we doctor pictures all the time, the terms utilized in Photoshop, originated in the film industry, burning, dodging, cropping. Any questions about doctoring either film or digital can be resolved by an expert"

My company was the complainant in a large lawsuit 8 years ago. My attorney told me to photo document some of our claims. First question I asked was "do I have to use a film camera? Absolutely not, any camera is OK".

Best Wishes Everyone


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## faber307 (Jan 22, 2007)

No reply from the pool guy.
I'm not calling them.
I was curious to go through with the tests.
but maybe I'm dodging a headache.

I'll be sure to get right on bidding his pool installs this spring.
:no:


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## leland (Dec 28, 2007)

*Cameras..*

I don't know how the courts feel, But I know some Recon folks with the FD& PD here and they all use film, some the instant polaroids including the insurance guys.


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