If you have a 10 amp current leaving a hot wire underground before the meter and the current returns through the neutral, the meter won't register the power or energy use.
*Shallow end, being shocked when grabbing railing*
- Thread starter gamerfan2004
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- May 3, 2007
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That is a likely scenario or it could be from the neighbor or another service line. The two key facts here are:
A) Cut power to the home (both power company and solar) and shock still exists. Means to me the issue is not related to anything in the house unless there is a third power source at the home.
B) Cut the power company distribution node power and the shock goes away. This means the power source is on the mains power distribution network. Again, could be a neighbor or a service line that is powered off the same distribution node.
Also, residential power is split-phase power where one 3-phase leg feeds a split-phase transformer which generates two 180 degree phases. The center tap is the neutral and is grounded at the transformer and at the home. However, there is not a separate "ground" sent with the 2 hot wires and neutral as it would be redundant. The neutral is already grounded at two points. This is why one should consider the neutral as a voltage reference. Everything else should be measured against that. To me it doesn't make sense to say the neutral is carrying excess voltage or noise. It is the reference. It is the hot lines that cause shocks, not the neutral.
Split-phase electric power - Wikipedia
The most likely explanation is that there is a hot wire (not necessarily 120v) separate from the OPs home, that is exposed underground but has the same voltage reference as the power company neutral (i.e. is not isolated). You always need to complete the circuit to get shocked. The OP gets shocked when the bonding is connected to neutral/ground but does not when disconnected. This does not mean the issue is the house. It only means the circuit is being completed. You can grab a hot line and not be shocked as long as there is not a path to ground or at least a high resistance path.
If you have a hot line with an exposed part leaking current underground, it is probably getting back to the neutral through the ground rod and the bonding grid, which is functionally equivalent to a second ground rod.
If you can separate the bonding grid from the grounds, then the current will be mostly going through the ground rod and you can check for voltage, frequency, waveform and current between the ground rod and the ground wire going to the neutral/ground bar.
If you can separate the bonding grid from the grounds, then the current will be mostly going through the ground rod and you can check for voltage, frequency, waveform and current between the ground rod and the ground wire going to the neutral/ground bar.
For mapping the yard, I would disconnect the ground rod and the bonding grid from the grounds and then measure from about 20 different points in the yard to the ground wire that usually connects to the ground rod.
Get a good connection in the yard by pouring some water on a spot and then putting in a metal stake that goes at least 12" deep.
Get a good connection in the yard by pouring some water on a spot and then putting in a metal stake that goes at least 12" deep.
- May 3, 2007
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Grounding rods only pull the local area earth ground to the potential of whatever you are grounding. A house ground is not to provide a ground to the house but to pull earth ground around the house to the same potential as the power distribution network neutral. Earth resistance is actually pretty high so if current is flowing from one point to another, potential differences can arise at different locations in the yard. So I would agree that it would be beneficial to remove the house ground rod from house ground wire. This may increase the potential differences you measure.
Also, as I mentioned before, volt meters have very high input impedance. This makes measuring voltage differences between locations challenging because without a current draw, there are no voltage drops (aka voltage differences). So a resistor across the leads of the volt meter allows current to flow and voltage differences to arise. But again to be effect, one lead should always be connected to the house neutral/ground wire to establish a valid reference.
Or, you could just measure current which uses an internal resistor. In fact, this is probably going to be the most sensitive measurement.
Also, I would disconnect the pool equipment ground from the bonding wire and all the other equipment.
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Also, as I mentioned before, volt meters have very high input impedance. This makes measuring voltage differences between locations challenging because without a current draw, there are no voltage drops (aka voltage differences). So a resistor across the leads of the volt meter allows current to flow and voltage differences to arise. But again to be effect, one lead should always be connected to the house neutral/ground wire to establish a valid reference.
Or, you could just measure current which uses an internal resistor. In fact, this is probably going to be the most sensitive measurement.
Also, I would disconnect the pool equipment ground from the bonding wire and all the other equipment.
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Some digital meters have had a LoZ or low impedance setting for sometime now.
I will be be very busy throughout this week and won't be testing very much. However, I was oblivious and I sincerely apologize for my stupidity. Please don't judge me, I've been under a ton of stress lately. The local distribution box is on the opposite side of my cul-de-sac. I know, I know, I know, please don't burn me at the stake. It's about 100' away.
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It's all good, no one should be doing any stake burning...searing maybe but not burning.
Ok, if you can get the power company to mark the wire runs from the box to your property and your neighbor's property on both sides, that will give you a good idea about where to map.
If you can draw a diagram of your basic property and the wire runs from the box, that would help us help you figure out where the problem might be.
If you can draw a diagram of your basic property and the wire runs from the box, that would help us help you figure out where the problem might be.
- May 3, 2007
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Power lines from the distribution node should all be in conduit so even if the insulation is compromised, the conduit should keep the lines isolated. To me that is a much less likely scenario. More likely is one of your neighbors did a DIY install and did not run the lines in conduit and then proceeded to break the insulation of the wire.
I would start close to the pool where the problem exists. Instead of mapping the entire yard, you could save some time by starting with a small map of 4 points in a 1-2 meter square. The corner with the highest current is the new corner for the next square in that direction. Continue until the current is about even on all four corners.
I would start close to the pool where the problem exists. Instead of mapping the entire yard, you could save some time by starting with a small map of 4 points in a 1-2 meter square. The corner with the highest current is the new corner for the next square in that direction. Continue until the current is about even on all four corners.
Can you draw a basic property diagram including where the house, pool, meter, transformer etc are?
Are you sure that that transformer feeds your house?
Are you sure that that transformer feeds your house?
Yeah, I'll do this on my lunch break tomorrow. I would think so, but I'm not 100%. The next one is further down the street on the same side as this one.
But, if there is an in-ground current leak, where the current flow is from the physical earth to the pools bonded ground, how does holding the railing while standing in water complete the circuit?
Isn't the railing bonded at the same ground potential as the water in the pool? Is the railing itself not touching the water? It the pool is bonded and the railing is bonded too the exact same ground via metal, how can a human be a better conductor than either the water bond or the railing bond?
I guess I'm surprised that there is such a difference in potential between a railing and water if the bond is equal for both. Wouldn't the pool bonding or at least the pool light niche bonding (assuming you have them) be a more likely way to complete the circuit than going through the water-to-skin and skin-to-railing?
Isn't the railing bonded at the same ground potential as the water in the pool? Is the railing itself not touching the water? It the pool is bonded and the railing is bonded too the exact same ground via metal, how can a human be a better conductor than either the water bond or the railing bond?
I guess I'm surprised that there is such a difference in potential between a railing and water if the bond is equal for both. Wouldn't the pool bonding or at least the pool light niche bonding (assuming you have them) be a more likely way to complete the circuit than going through the water-to-skin and skin-to-railing?
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There are pictures in the thread that show the railing does not go into the water. Both mounting points are on the deck.
Yes normally in a equipotential plane that is complete there are no differences in potential in any metal around the pool.
Clearly the bond has been broken between the railing and the deck and the water or there would be no difference in potential.
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Orion7319
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If I remember correctly (without scrolling back though this thread) aren’t the cups that hold his railing aluminum and starting to decay? I would assume that there is a good possibility that the bond connection point rusted away at the cups. Wouldn’t it be sufficient to simply repair the bonding grid?
- May 3, 2007
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The issue is more complicated than that.
First, there is a voltage difference between the water and the railing. We don't know exactly which is compromised. It could be that the water is bonded properly and that the railing bond has the excess voltage. So if you reduce resistance between the railing and it's bond, you could potentially make the problem worse.
It would be better to lay a separate bonding wire temporarily from the pump directly to the railing. This would ensure a proper bond to the railing. After that, one could then measure the voltage again between the railing and the water and if there is still voltage, it is the water that has been compromised. However, if it goes away, then the railing bond has been compromised. I had suggest this many many posts ago.
First, there is a voltage difference between the water and the railing. We don't know exactly which is compromised. It could be that the water is bonded properly and that the railing bond has the excess voltage. So if you reduce resistance between the railing and it's bond, you could potentially make the problem worse.
It would be better to lay a separate bonding wire temporarily from the pump directly to the railing. This would ensure a proper bond to the railing. After that, one could then measure the voltage again between the railing and the water and if there is still voltage, it is the water that has been compromised. However, if it goes away, then the railing bond has been compromised. I had suggest this many many posts ago.
Orion7319
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I didn't post on this yet, mainly because of time. After doing everything that I did over the weekend, I ran a bonding wire from the pump and did some testing. I don't have the measurements in front of me, I specifically remember the anchors in the shallow end only had like 50mV AC. The decking over near it was around 1.8VAC. Water was around 2.4VAC, deep end ladder area all registered around 2.6VAC, area at the deep end light was around 2.6VAC as well.
Even if the water is bonded, it is only bonded at 1 or 2 places.
From the point that it is bonded, there is significant resistance to every other point in the water.
In the Mike Holt video where he dropped a live wire in the pool, he measured voltage gradients in the water.
He measured 10.35 amps of current.
The water was not all at the same potential.
If you have a hot wire underground and current is going from the hot wire to the neutral, there is a voltage difference between the hot wire and the neutral of probably 120 volts.
If we assume that there is 10 amps of current, the resistance of the ground should be 12 ohms.
The ground acts like a resistive load like a heating element and the power usage would be 1,200 watts.
If you have current flowing, you will have voltage differences even if things are bonded.
The voltage essentially drops from 120 to 0 going from hot to neutral.
From the point that it is bonded, there is significant resistance to every other point in the water.
In the Mike Holt video where he dropped a live wire in the pool, he measured voltage gradients in the water.
He measured 10.35 amps of current.
The water was not all at the same potential.
If you have a hot wire underground and current is going from the hot wire to the neutral, there is a voltage difference between the hot wire and the neutral of probably 120 volts.
If we assume that there is 10 amps of current, the resistance of the ground should be 12 ohms.
The ground acts like a resistive load like a heating element and the power usage would be 1,200 watts.
If you have current flowing, you will have voltage differences even if things are bonded.
The voltage essentially drops from 120 to 0 going from hot to neutral.
When you took the voltage readings around your pool with the wire attached to the bonding point on the pump motor did you happen to switch to continuity as well and test the bonding grid?