Old code question..real old.

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pscobb

Member
I'm having an issue with a swimming pool bonding grid or lack thereof. My customer is getting a 1.5 vac jolt when approaching the light trim. The pool was built in 1959 but was updated with a new niche, pvc conduit and deck box and 12 vac light. I am sure this was the only update to the pool. Was there a code on pool bonding in 1959? If so, what was the content of the article. This information would help me in my diagnosis. Thanks for any input. I'm getting the voltage reading even after de-energizing the main service.
 

tom baker

First Chief Moderator
Staff member
The voltage you are seeing is due to the utility bonding its neutral to the earth in multiple locations. You can never bond it away, but only mask it, so you don't feel the difference.
Mike Holts web site will have lot of information on this, search for "stray voltage".
Having said that, there are many people here who install pools for a living and can offer suggestions.
 

Mule

Senior Member
Location
Oklahoma
I'm having an issue with a swimming pool bonding grid or lack thereof. My customer is getting a 1.5 vac jolt when approaching the light trim. The pool was built in 1959 but was updated with a new niche, pvc conduit and deck box and 12 vac light. I am sure this was the only update to the pool. Was there a code on pool bonding in 1959? If so, what was the content of the article. This information would help me in my diagnosis. Thanks for any input. I'm getting the voltage reading even after de-energizing the main service.


Since you still get the reading with the service disconected. I would see if that 1.5v would bleed off, and will it draw a tiny arc? use a piece of wire instead of your meter (power off of course) is there something that could building up static? is your humidity running low? what about chemical reactions?
 

Volta

Senior Member
Location
Columbus, Ohio
Like Tom said, that is probably utility current. Maybe at least a ground ring could be put in with some bonding, if a modern perimeter grid can't be done.

Article 680 started in 1962. The '59 issue has no entry in the index for pool, swimming, tub, or water.
 

Mule

Senior Member
Location
Oklahoma
Like Tom said, that is probably utility current. Maybe at least a ground ring could be put in with some bonding, if a modern perimeter grid can't be done.

Article 680 started in 1962. The '59 issue has no entry in the index for pool, swimming, tub, or water.

The utility current makes good sense to me, good call.. I overlooked that one.....:roll:
 

Jim W in Tampa

Senior Member
Location
Tampa Florida
You just might have a neutral problem either on poco side or yourself. Posably even from a neighbor. Your pool is a ground and might be picking up something from neighbors house if they have bad grounding
 

e57

Senior Member
Your pool is a ground and might be picking up something from neighbors house if they have bad grounding
That would mean they have GREAT GROUNDING!!!! (if that were the problem???)

Even though the service may be off and no current from the house, there may always be different potential from the earth around the pool to the grounded conduit(s). (No matter how good the grounding of all the services in the neighborhood.) Which is the whole point behind equipotential grids and such. i.e. getting the area around the pool to nearest the same potential as the grounded items in or near it. Even if that potential is elevated from the earth generally in another location - like say over at any ground rod of any service including the one at that residence.

Question for the OP - what are you measuring to and from, and what with? I assume the trim is under water? I would look into the grounding and/or bonding of the niche and local boxes.
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
Occupation
retired electrician
This is exactly why the code should not permit any electrical equipment in the pool and should prohibit the connection of the pool bonding system to the electrical grounding system. When we connect the pool bonding system to the electrical grounding system as now required in the code we energize the pool bonding system with a voltage that is equal to the voltage drop on the utility primary neutral conductor.
This would require major changes in the design and installation of pools, so I expect that the code will not change and will continue to require us to energize it.
 

ub8up1

Member
Location
NJ
I'm having an issue with a swimming pool bonding grid or lack thereof. My customer is getting a 1.5 vac jolt when approaching the light trim. The pool was built in 1959 but was updated with a new niche, pvc conduit and deck box and 12 vac light. I am sure this was the only update to the pool. Was there a code on pool bonding in 1959? If so, what was the content of the article. This information would help me in my diagnosis. Thanks for any input. I'm getting the voltage reading even after de-energizing the main service.
I'm a little confused on the "getting a 1.5 vac jolt when approaching the light trim"...How was that measurement taken, under water ?
 

pscobb

Member
I'm a little confused on the "getting a 1.5 vac jolt when approaching the light trim"...How was that measurement taken, under water ?
I connected a solid conductor to the brass pool light j-box and set my fluke23 to 200vac and touched one lead to the wire and the other lead to the water in the pool. This test was done with the light on and off, with all equipment grounding conductors connected and disconnected, with the #8 solid conductor connected and disconnected, with the pool equipment panel energized and de-energized. All with the same resulting reading of between 1.5 vac and 2 vac. Is this enough of a voltage to cause problems with someone wearing a pace maker?
 

ub8up1

Member
Location
NJ
Don't know much about pacemakers and such. But as a veteran of 30years of doing pool wiring I can pretty much bet that the pool light isn't bonded to the deck box.
 

pscobb

Member
Bet it up

Bet it up

Don't know much about pacemakers and such. But as a veteran of 30years of doing pool wiring I can pretty much bet that the pool light isn't bonded to the deck box.
I replaced the light fixture and yes it has a #8 solid green conductor connected to the light niche and I have the wet underwear to prove it.
 

iaov

Senior Member
Location
Rhinelander WI
A 1.5 vt AC jolt?? I'm having a VERY hard time believing anyone is even feeling 1.5 volts much less being jolted by it. If someone is recieving a noticable shock it is not coming from 1.5 volts. You need to do some further investigating here.
 

ub8up1

Member
Location
NJ
I replaced the light fixture and yes it has a #8 solid green conductor connected to the light niche and I have the wet underwear to prove it.
God love you young man, been there did that...he, he
Since you got a reading of 1.5, 2 volts between the deck box and the water, I would suspect that the "Green' bond wire is broken....those damm helpers. After you know for darn sure you have a good connection on the bond, I can't tell you how many times that I found that the bond wire at the niche connection looked like it was connected but it was broken right at the niche connection, in the potting compound . It would be impossible to get a reading between the niche and the deck box if they were bonded together.
 

ub8up1

Member
Location
NJ
A 1.5 vt AC jolt?? I'm having a VERY hard time believing anyone is even feeling 1.5 volts much less being jolted by it. If someone is recieving a noticable shock it is not coming from 1.5 volts. You need to do some further investigating here.
Try this..
1: get a cold beer can
2: put can on concrete deck in a little pool of water
3: jump into to water
4: without touching the pool deck at all , stick out your tongue and touch the beer can
The 1.5 volts WILL be felt

Maybe enough to kill you if you had a pacemaker, I guess, maybe, who knows
 
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