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I need to figure out this electrical issue.

I have a client who has a Hot tub, he called me a while back because when he wad standing on the ground (bare feet) he felt a tingle when touching water in hot tub.

So using my volt metre I was getting 9.6 volts from the surface of the water to the earth beside tub, I also checked for voltage around yard and found 8 volts from my panel ground wire to earth, as well as sprinkler system to earth. From the exposed ground wire on hydro pole, meter is reading 3 volts to earth.

Next I shut off the main disconnect switch thinking it may be possible I had voltage leakage through a nicked line somewhere in the home. Now with no power from main disconnect into the house I was still getting the same voltages through out the yard 馃.

After some thought and a phone call to a fellow electrician he recommended I remove the neutral from the panel, so I did, completely removed neutral from the lug.
I now had no voltage being picked up any where! 馃槉
I reconnected the neutral back into panel and problem came back.
I called hydro and they sent out a trouble crew to investigate, they said there is no issues with voltages on their end.
I've never came across this before and don't know what to do to remedy, it makes sense in my head that when the main neutral is disconnected from hydro's end and problem goes away that there must be something wrong with grounding of transformer or something along those lines.

The 400 Amp panel I installed in the home is grounded with #2 bare copper to 2 ground plates baried approx. 36" below grade.

Please respond if you have any ideas of what could be the issue and how to correct the problem.
 

Hackenschmidt
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This sounds like the problem is with a neighbor on the same transformer, they have a loose neutral or lost their neutral. With your neutral connected, the path through ground (through your premises) is the path of least resistance back to the transformer. With it disconnected, the path through your earth is still a lot higher resistance than the path through their earth, so the voltage goes away.

Just a stab.
 

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Since the entire North American power grid has every neutral grounded at every point, there is literally current coming in to every neutral from the outside. Because there are an infinite amount of parallel paths, some current, no matter how small, must be flowing through every land surface down to the smallest square miliimeter.

Your problem is closer to home I think. First thing to do is load each phase and check voltage to neutral. Put 1500 watts of a space heater on one phase and check the voltage to neutral as you vary the power of the heater. Do it for both phases. If the voltages to neutral are swinging wildly like A phase is 80 V but B phase is 160, there is a problem with the neutral to your panel, up and including the transformer.
If not, there is something wrong somewhere nearby. If the hot tub is the main concern, a good does of equipotential bonding should cure the symptom.

Running a ground ring around the entire property and bonding it back to the neutral at the service may be effective.
 

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Thank you I'll try getting ahold of the neighbor to gain access and check that.
If you can't work with the neighbor the next step would be to get the power company involved. Once the problem home is located they have the ability to condemn and disconnect. It could also be on their side.

A bad neutral connection to a neighbors home.
Anywhere from their panel, meter, weatherhead, utility splice point, or transformer.

Another thought at a neighbor house it could be a circuit going out in the yard like a shed, pool equip, or lighting.
 

Just trying to get home
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Follow the voltage drop with your client's house down/disconnected.

Like these guys said ^^^ likely it will lead to a neighbor's house.
 

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If all of the voltage readings between the electrical system's grounded parts (raceways, grounding electrodes, hot tub water, etc.) and true earth stay the same regardless of whether the main breaker is on or off, then the problem is definitely not with your customer's property. It's also not likely a problem with a neighbor's neutral either, since that would show up as CURRENT through your customer's neutral-ground bond, not the voltage differentials you're measuring between bonded parts and earth - unless your customer also happens to have a bad neutral at the same time, which would show up with other symptoms.

The main problem that causes these symptoms is a bad connection between the transformer and the utility's system neutral. In other words, this is likely a primary-side issue. The transformer's primary current is returning to the substation through the earth, via the customer's grounding electrodes (and other accidental parallel paths - like the customer's body when he touches the hot tub water). You should see the voltages rising when heavy loads are applied.

Disconnecting the neutral is dangerous (even with the main breaker off) because you are removing one of the main return paths for the transformer's primary current. If the pole-base grounding electrode is compromised too, you could see up to 7200V on that open neutral! Not good. The utility needs to take another look at this.
 

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You also must look into whether the hot tub is EXCESSIVELY insulated to ground.

My Brother in Law faced this issue.

What can happen is that current/ charge can be induce directly into the swirling water... something first noted by Faraday.

For the water is ionized by body sweat, which keeps rising over time, until the HO flushes it all out.

You'd be astounded as to how salty a hot tub can get, as the water keeps evaporating and the HO keeps refilling it.

You're getting a dose of salts from the potable water, too.

&&&&

So what happens is that, at first, there's no problem at all.

Then, ever so gradually, the HO notices that he's getting hit with jolts to the groin when he straddles the hot tub and the surrounding surface.

In my BiL's case, I measured 45 volts. (!!!)

The actual current involved is trivial, BTW.

I made everything go away by dropping a copper wire into the water and running it off to the GEC System.

Poof, the volts dropped to zero... and stayed that way.

&&&

Naturally, everyone wants to know how the effect gets rolling.

1) The motor is not contained within a Faraday box// shield.

2) The circulating pump injects salty water ( it's ionized, of course ) right through the magnetic field of the motor driving the pump.

3) A feeble amount of energy is then transferred to the Na+ and Cl- ions.

4) It has no where to go, so it starts to become a bucket of capacitance.

&&&

This process bears no small resemblance to the headache of phantom voltages often seen with Romex cables.

In the ghost voltage case, you're dealing with capacitive coupling.

&&&

When you pass a conductor through a magnetic field, energy is transferred.

In the hot tub, the conductor is the 'brine' -- not copper, not metal.

The energy transference is pathetic in this instance.

But when the discharge of said energy is through your groin, you sure do notice.

&&&

I've lost count for the number of times e-men hit the Internet with this exact same 'trouble.'

I am not claiming that this is your problem, here.

It's just something that you need to be aware of... before you go insane.

If a bonding/grounding conductor makes the voltage evaporate... and after it's removed ( the wire ) the voltage difference stays at zero... but comes back days or weeks later... ever rising...

Well, now you know.

The effect is proportional to pump run time, under cut by charge bleed-off by any means.

&&&

It's ironic, the manufacturer went to extreme lengths to isolate, electrically, the hot tub's water from the outside world.

Which is what triggers this effect.

Flushing the water back down to really, really fresh also cuts this effect way, way back.
 

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You also must look into whether the hot tub is EXCESSIVELY insulated to ground.

My Brother in Law faced this issue.

What can happen is that current/ charge can be induce directly into the swirling water... something first noted by Faraday.

For the water is ionized by body sweat, which keeps rising over time, until the HO flushes it all out.

You'd be astounded as to how salty a hot tub can get, as the water keeps evaporating and the HO keeps refilling it.

You're getting a dose of salts from the potable water, too.

&&&&

So what happens is that, at first, there's no problem at all.

Then, ever so gradually, the HO notices that he's getting hit with jolts to the groin when he straddles the hot tub and the surrounding surface.

In my BiL's case, I measured 45 volts. (!!!)

The actual current involved is trivial, BTW.

I made everything go away by dropping a copper wire into the water and running it off to the GEC System.

Poof, the volts dropped to zero... and stayed that way.

&&&

Naturally, everyone wants to know how the effect gets rolling.

1) The motor is not contained within a Faraday box// shield.

2) The circulating pump injects salty water ( it's ionized, of course ) right through the magnetic field of the motor driving the pump.

3) A feeble amount of energy is then transferred to the Na+ and Cl- ions.

4) It has no where to go, so it starts to become a bucket of capacitance.

&&&

This process bears no small resemblance to the headache of phantom voltages often seen with Romex cables.

In the ghost voltage case, you're dealing with capacitive coupling.

&&&

When you pass a conductor through a magnetic field, energy is transferred.

In the hot tub, the conductor is the 'brine' -- not copper, not metal.

The energy transference is pathetic in this instance.

But when the discharge of said energy is through your groin, you sure do notice.

&&&

I've lost count for the number of times e-men hit the Internet with this exact same 'trouble.'

I am not claiming that this is your problem, here.

It's just something that you need to be aware of... before you go insane.

If a bonding/grounding conductor makes the voltage evaporate... and after it's removed ( the wire ) the voltage difference stays at zero... but comes back days or weeks later... ever rising...

Well, now you know.

The effect is proportional to pump run time, under cut by charge bleed-off by any means.

&&&

It's ironic, the manufacturer went to extreme lengths to isolate, electrically, the hot tub's water from the outside world.

Which is what triggers this effect.

Flushing the water back down to really, really fresh also cuts this effect way, way back.
You seriously have no idea what you are talking about. I would love to see where you pull this stupid assed **** out of.
 

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You seriously have no idea what you are talking about. I would love to see where you pull this stupid assed **** out of.
I cured the problem.

Poof.

If I'm over your head...

I can live with it.

&&&

You ought to go back and read Faraday's old experiments.

One of his first amazements was the discovery that ionized water could induce a current in his coil as it flowed past.

In this instance the power flow is reversed.

Look it up... dufus.
 

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Here, all Hot Tubs have to have Equipotential grounding.

Sent from my XT1254 using Tapatalk
No they do not. 99% of hot tubs are portable. That is an old wives tale. The only ones that need that are permanent ones built out of concrete or other methods.
 

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My Brother in Law's unit didn't have a decent grounding connection until I stepped in.

Poof, the problem went away.

The OP mentions 9.6 Volts.

That's strangely HIGH relative to what's nearby.

It's a quick test to drop in a bonding conductor.

If it's due to circulation, the voltage will evaporate -- and STAY gone -- even after you removed your test bonding jumper.

Then it will creep back up days later.

This is a pretty good indication that the unit is plugged into a rotten grounding connection.

OP: BTW, when the neutral is lifted,... you have an open neutral... known to give you false confidence// fake readings from that point forward.
 

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No they do not. 99% of hot tubs are portable. That is an old wives tale. The only ones that need that are permanent ones built out of concrete or other methods.
Obviously you don't know the local ordinances here. But, you know it all!!!

Sent from my XT1254 using Tapatalk
 

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1) The motor is not contained within a Faraday box// shield.

2) The circulating pump injects salty water ( it's ionized, of course ) right through the magnetic field of the motor driving the pump.

3) A feeble amount of energy is then transferred to the Na+ and Cl- ions.

4) It has no where to go, so it starts to become a bucket of capacitance.
That's just not right. The total number of + and - charge carriers in the solution remains constant unless you're preferentially removing ions though some electrochemical process (and you're not). The net charge in the tub will remain neutral unless you do some serious, intentional, difficult electrochemistry (and again, you're not).

When you pass a conductor through a magnetic field, energy is transferred.

In the hot tub, the conductor is the 'brine' -- not copper, not metal.
Nah. There's no static magnetic field to move the water through, and the direction of movement is not orthogonal to the direction of current flow (the geometry is all wrong). The idea you're envisioning is a magnetohydrodynamic pump or motor - which is really cool stuff, but totally different from a hot tub. The physics just doesn't add up here. Everything about the flows, the currents, and the fields is all wrong for those effects to come into play. Every step of that process is a "right hand rule" interaction involving a current, a magnetic field, and a force or movement, with each of those three vectors orthogonal to one another. A hot tub pump setup isn't shaped right and is missing critical parts.

The energy transference is pathetic in this instance.
It's zero. That's not what's going on. Look for a different explanation.

I am not claiming that this is your problem, here.
That's not the problem in anybody's hot tub. There might be some problem, but this isn't the cause of it.

It's ironic, the manufacturer went to extreme lengths to isolate, electrically, the hot tub's water from the outside world.

Which is what triggers this effect.
The water should be bonded, and so should nearby conductive surfaces. Even if an equipotential grid may not be required for a portable tub, decent bonding of touchable stuff around the tub is a great idea and it fixes a lot of potential problems before they start. It would have prevented this OP's customer from noticing the problem with his electrical service!

But the real problem this guy has is probably a bad primary neutral on his utility transformer. I'd bet on it (not too much money though). Not much else can cause this specific set of symptoms.
 

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Obviously you don't know the local ordinances here. But, you know it all!!!

Sent from my XT1254 using Tapatalk
Obviously I do not. Would you please post the "local" codes or even the NEC code section to enlighten me?
It sucks being as stupid as I am.
 

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That's just not right. The total number of + and - charge carriers in the solution remains constant unless you're preferentially removing ions though some electrochemical process (and you're not). The net charge in the tub will remain neutral unless you do some serious, intentional, difficult electrochemistry (and again, you're not).



Nah. There's no static magnetic field to move the water through, and the direction of movement is not orthogonal to the direction of current flow (the geometry is all wrong). The idea you're envisioning is a magnetohydrodynamic pump or motor - which is really cool stuff, but totally different from a hot tub. The physics just doesn't add up here. Everything about the flows, the currents, and the fields is all wrong for those effects to come into play. Every step of that process is a "right hand rule" interaction involving a current, a magnetic field, and a force or movement, with each of those three vectors orthogonal to one another. A hot tub pump setup isn't shaped right and is missing critical parts.



It's zero. That's not what's going on. Look for a different explanation.



That's not the problem in anybody's hot tub. There might be some problem, but this isn't the cause of it.



The water should be bonded, and so should nearby conductive surfaces. Even if an equipotential grid may not be required for a portable tub, decent bonding of touchable stuff around the tub is a great idea and it fixes a lot of potential problems before they start. It would have prevented this OP's customer from noticing the problem with his electrical service!

But the real problem this guy has is probably a bad primary neutral on his utility transformer. I'd bet on it (not too much money though). Not much else can cause this specific set of symptoms.

Argue with Faraday.
 
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