Swimming Pools

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kwired said:
Well technically it is no longer bonded if the path is opened or gains resistance.
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Well, everything has resistance, bonded or not.
I was just pointing out, one may think everything around a pool is bonded, but then still have meter readings for potential diff. That falls into realm of no bonding and/or faulty bonding. Which may be the case for OP.

Or, some hot wire became exposed to the water, which creates potential diff to any grounded wire and likely the bonding, because most times the bonding is tied somewhere to ckt EGC.

Or, the bonding itself is in contact with hot wire via direct or indirect contact, and the tingle is between "everything that is bonded" and something that only touches grounded CCC or the EGC.

And then the other question to ask, is the power to this pool on GFCI?

Yes, I stated the obvious, but worth stating.
 
FionaZuppa said:
Well, everything has resistance, bonded or not.
I was just pointing out, one may think everything around a pool is bonded, but then still have meter readings for potential diff. That falls into realm of no bonding and/or faulty bonding. Which may be the case for OP.

Or, some hot wire became exposed to the water, which creates potential diff to any grounded wire and likely the bonding, because most times the bonding is tied somewhere to ckt EGC.

Or, the bonding itself is in contact with hot wire via direct or indirect contact, and the tingle is between "everything that is bonded" and something that only touches grounded CCC or the EGC.

And then the other question to ask, is the power to this pool on GFCI?

Yes, I stated the obvious, but worth stating.
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Power to pool panels are seldom from a GFCI breaker. This is due to if only one thing with a fault would trip the GFCI, that would cause everything to be without power.
Now, certain equipment is required to be GFCI protected.
If the OP's problem is stray voltage, that won't trip a GFCI.
 
Little Bill said:
Power to pool panels are seldom from a GFCI breaker. This is due to if only one thing with a fault would trip the GFCI, that would cause everything to be without power.
Now, certain equipment is required to be GFCI protected.
If the OP's problem is stray voltage, that won't trip a GFCI.
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Hot wire to water, then Mrs Doubtfire bridges between water and bond/egc with her arm and bridges 7ma. That won't trip GFI? But w/o her arm that way the hot wire is leaking 2ma across the water.
 
FionaZuppa said:
Hot wire to water, then Mrs Doubtfire bridges between water and bond/egc with her arm and bridges 7ma. That won't trip GFI? But w/o her arm that way the hot wire is leaking 2ma across the water.
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How often is a 120 volt conductor at/in the pool?

I don't know a lot about details of pools but other than underwater luminaires which I don't believe is too common to see line voltage at those anymore most the line voltage items are somewhat remote from the pool, pumps, heaters etc. Pretty sure they are not allowed within certain distance of the pool either or at least need a barrier of some sort so users can't come in contact with pool and those items at same time.
 
FionaZuppa said:
Hot wire to water, then Mrs Doubtfire bridges between water and bond/egc with her arm and bridges 7ma. That won't trip GFI? But w/o her arm that way the hot wire is leaking 2ma across the water.
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Little Bill said:
Power to pool panels are seldom from a GFCI breaker. This is due to if only one thing with a fault would trip the GFCI, that would cause everything to be without power.
Now, certain equipment is required to be GFCI protected.
If the OP's problem is stray voltage, that won't trip a GFCI.
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Apparently you missed where I said "stray voltage"!
Never said anything about a hot wire to water and old miss Doubtfire!
 
Stray voltage can come from anything. A pool motor, pool light(yes there are lots of 120v pool lights still, any pool equipment, pool cover, or something completely un related to the pool. Even utility with compromised neutral. If everything is bonded properly the owner would not have felt the tingle.
 
SSDriver said:
Stray voltage can come from anything. A pool motor, pool light(yes there are lots of 120v pool lights still, any pool equipment, pool cover, or something completely un related to the pool. Even utility with compromised neutral. If everything is bonded properly the owner would not have felt the tingle.
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A pretty broad definition of it can come from anything.

Most the time however stray voltage to this trade is voltage between what is supposed to be grounded objects and true earth and typically is the result of voltage drop on a MGN conductor somewhere in the supply system. At least that is my observation.
 
Voltage has to come from somewhere, and if it's not sourced from premise wiring then sure, another issue to deal with.
All that said, it's even possible to get zing between metal near the pool and bonding, and not have a GFI trip. This is why it's good to have GFI and make sure bonding is tied to EGC very well, don't rely on just a pump case to carry that connection between the two, etc.
 
FionaZuppa said:
Voltage has to come from somewhere, and if it's not sourced from premise wiring then sure, another issue to deal with.
All that said, it's even possible to get zing between metal near the pool and bonding, and not have a GFI trip. This is why it's good to have GFI and make sure bonding is tied to EGC very well, don't rely on just a pump case to carry that connection between the two, etc.
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If the metal is near the pool it is supposed to be bonded.

The whole concept of equipotential bonding is to eliminate voltages between objects pool users are able to come in contact with, we don't care as much if the entire pool and EB system are 1000 volts above remote earth location, just don't want any voltage between objects pool users can contact simultaneously. "Bird on a wire" concept so to speak.
 
mike5456 said:
Good morning, What is the best way to check for stray voltage in a swimming pool? The homeowner feels a tingling near the skimmer, I could not reproduce it.
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How did you try to test it? if the pool deck is dry concrete you may not find the same issues that wet concrete will have.
 
acrwc10 said:
How did you try to test it? if the pool deck is dry concrete you may not find the same issues that wet concrete will have.
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If feeling tingle near the skimmer, seems like a good chance that will be while immersed in the pool?

Regardless when someone says they are feeling something near a certain object you need to measure from that object to anything within reach or even a little beyond reach of said object, if deck is within reach then you might want to make sure it is wet when you take any measurements to it.
 
Tingles indicate a difference in potential, but not necessarily which part is energized. It could be the skimmer, or everything else. I would measure for voltage between a known good electrical ground and various metallic parts, as well as the water itself.

This is a case where a high-impedance voltmeter would be the right instrument to use. A long wire would work for the grounded lead, and something like a stainless-steel mesh or scouring pad should make a good water probe.
 
kwired said:
If feeling tingle near the skimmer, seems like a good chance that will be while immersed in the pool?

Regardless when someone says they are feeling something near a certain object you need to measure from that object to anything within reach or even a little beyond reach of said object, if deck is within reach then you might want to make sure it is wet when you take any measurements to it.
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I have a hard time visualizing feeling a tingle in a pool when not touching something else. I’d think touching another object would have to be involved.
 
retirede said:
I have a hard time visualizing feeling a tingle in a pool when not touching something else. I’d think touching another object would have to be involved.
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I understand there can be gradients just like step potential. One might be in part of the pool and reach forward/backward into another part and feel a shock should there be stray voltage somewhere in the area. That is one of the reasons for bonding the water.
 
LarryFine said:
Tingles indicate a difference in potential, but not necessarily which part is energized. It could be the skimmer, or everything else. I would measure for voltage between a known good electrical ground and various metallic parts, as well as the water itself.

This is a case where a high-impedance voltmeter would be the right instrument to use. A long wire would work for the grounded lead, and something like a stainless-steel mesh or scouring pad should make a good water probe.
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should have maybe said something that is known to be well bonded to the equipotential bonding system of the pool, that is the reference you are trying to maintain throughout the pool.

Outside of an actual fault of an ungrounded conductor, most stray voltages in a pool would be because of a hole in the equipotential bonding and that hole will likely be at or near actual ground potential
 
Little Bill said:
I understand there can be gradients just like step potential. One might be in part of the pool and reach forward/backward into another part and feel a shock should there be stray voltage somewhere in the area. That is one of the reasons for bonding the water.
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If the gradient over a couple feet is enough to be able to be felt, the overall gradient would likely be huge, depending on the distance between the points energizing the water.
 
LarryFine said:
Tingles indicate a difference in potential, but not necessarily which part is energized.
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part A is 36v, part B is 160v (measured between part and EGC), but between A and B which part is "energized"?
 
FionaZuppa said:
part A is 36v, part B is 160v (measured between part and EGC), but between A and B which part is "energized"?
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EGC isn't always at same volts as earth, so is possible A, B and EGC are all "energized" relative to earth.

But in a pool what matters the most is what is voltage to the equipotential bonding system.
 
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