# Water line used as system ground.



## splatz (May 23, 2015)

There is always a parallel path through the GES as you describe, I think it's just that the resistance of the ground path is so much higher than the near-zero resistance of the service neutral that it should be very very small. 

I think the strongest clue is that the ground current is much higher at the neighbor's, that would indicate to me that the bonding and / or neutral issue is in that neighbor's system.


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## ELECTRICK2 (Feb 21, 2015)

All amp readings were taken at the first house.
We didn't have access to neighbors.
Current on a house system ground IMO should be very close to zero.

Quick recap.
Plug saw into neighbors outside recept. and turn it on.
Amperage on the system ground at first house goes from .5 to 4 or so


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## telsa (May 22, 2015)

Bingo.


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## PlugsAndLights (Jan 19, 2016)

Yes it's normal to use the city water pipe as system ground. 
Yes, the parallel path you described is there. 
Some time back I posted an engineering paper describing this 
uncontrolled current passing beneath our feet.The author saw 
it as risk that should be addressed. Whether the author was 
correct or not, this system is unlikely to change. The existing 
system is the cheapest way to protect the transmission equipment 
against lightning strikes. And yes, no matter what they say, the 
system grounding on each premise is there to protect the poco 
equipment and nothing more. 
P&L


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## 3DDesign (Oct 25, 2014)

There's a good chance the neighbor has an open neutral.


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## ELECTRICK2 (Feb 21, 2015)

P&L, so if the home owner pounded a couple of ground rods,
The amperage from the neighbors house would no longer be present.
Correct?


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## 3DDesign (Oct 25, 2014)

Around here, the copper water line is considered the primer ground. Ground rods are secondary.


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## PlugsAndLights (Jan 19, 2016)

ELECTRICK2 said:


> P&L, so if the home owner pounded a couple of ground rods,
> The amperage from the neighbors house would no longer be present.
> Correct?


Very likely would be reduced as the earth resistance would almost 
certainly be much higher than that of the city plumbing. On the 
other hand, cities are full of multi-grounded neutrals on plumbing
without rampant death. BTW, this sort of thing is most dangerous to 
our 4 legged cloven hoofed friends.

If you want to know a lot more about this, find the pdf below. I haven't 
read it in a few years but it really helps anyone who wants to better 
understand our distribution system. 
P&L
http://www.ecs.csun.edu/~bruno/MultiGroundedNeutralFinal_4-17-7.pdf

edit: btw, I always prefer gnd plates to rods, but that's just me.


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## telsa (May 22, 2015)

PlugsAndLights said:


> Yes it's normal to use the city water pipe as system ground.
> Yes, the parallel path you described is there.
> Some time back I posted an engineering paper describing this
> uncontrolled current passing beneath our feet.The author saw
> ...


Fundamentally wrong.

Grounding protects equipment multiple ways:

1) It 'hides' the structure from lightning strikes by making it an element of an equipotential plane.

2) It discharges switching transients -- the critters that are driving e-men nuts WRT LED drivers causing strobing effects.

But these transients are capable of injuring insulators/ dielectrics/ at every turn. Brief. Low evergy. High voltage.

3) Should a transformer go wrong, it is ESSENTIAL that the excess energy be bled off into the earth.

The death of an IBEW brother, in 1945, triggered this discovery the hardest way possible -- and the establishment of EUSERC.

BTW, it was MUCH to the astonishment of the EE community that such a situation could possibly exist.

It was beaten to DEATH, BTW.

The tale of EUSERC has been written up in the trades a couple of times.


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## ELECTRICK2 (Feb 21, 2015)

P&L, thanks. the reason I asked is I was never involved much in resi.
All commercial jobs I did, used ground rods, pilings etc for the system ground.

I thought this way of getting a system ground was iffy simply because of the electrical code.
Thou shall bond once and only once.


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## RePhase277 (Feb 5, 2008)

The neighbor's neutral current is returning via your customer's water line.


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## PlugsAndLights (Jan 19, 2016)

RePhase277 said:


> The neighbor's neutral current is returning via your customer's water line.


If by this you mean - a portion of the neighbour's neutral current 
is returning via your customer's water line with the amount determined 
by each of the parallel resistances, including any other customers on 
the same transformer, and this is normal and expected - then I agree. 
P&L


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## ELECTRICK2 (Feb 21, 2015)

RePhase277 said:


> The neighbor's neutral current is returning via your customer's water line.


Yes, a portion of it is, depending on the resistance of each path.
Which is what P&L was getting at.

Apparently I didn't splain myself very well.


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## ELECTRICK2 (Feb 21, 2015)

RePhase277 said:


> The neighbor's neutral current is returning via your customer's water line.


 
Just noticed you liked the idea that the neighbor has a bad neutral.
That's not it.

First house system ground amperage goes up when first house furnace turns on.
Where does this current go if neighbor has a bad neutral?


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## splatz (May 23, 2015)

I think if your customer puts in more ground rods, it will lower the resistance of the path through your customer's GES for their neighbor's neutral current, and they'll see MORE current on ground. 

I am not sure why your customer's furnace increased the current on ground if it's only a neighbor problem, maybe something at / in the transformer.


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## PlugsAndLights (Jan 19, 2016)

splatz said:


> I think if your customer puts in more ground rods, it will lower the resistance of the path through your customer's GES for their neighbor's neutral current, and they'll see MORE current on ground.
> 
> I am not sure why your customer's furnace increased the current on ground if it's only a neighbor problem, maybe something at / in the transformer.


Only if this was added without removing the system ground from the 
plumbing. Only way it makes sense is if it's one or the other. 
P&L


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## ELECTRICK2 (Feb 21, 2015)

splatz said:


> I think if your customer puts in more ground rods, it will lower the resistance of the path through your customer's GES for their neighbor's neutral current, and they'll see MORE current on ground.
> 
> I am not sure why your customer's furnace increased the current on ground if it's only a neighbor problem, maybe something at / in the transformer.


 
Splatz, I am not suggesting more ground rods.
There are no ground rods.

I suggest disconnecting ground from the water line
Pound a ground rod and hook up your system ground.

It's not a neighbor problem.
It's not a problem at first house.

The problem arises because we basically have a neutral bonded at 2 (Or more) points.


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## RePhase277 (Feb 5, 2008)

ELECTRICK2 said:


> Just noticed you liked the idea that the neighbor has a bad neutral.
> That's not it.
> 
> First house system ground amperage goes up when first house furnace turns on.
> Where does this current go if neighbor has a bad neutral?


To yet another neighbor. Surely there are more than two houses on the water line?

It's possible that there's a bad neutral at a transformer somewhere and this water line is acting as a sort of neutral bus for the whole neighborhood.


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## RePhase277 (Feb 5, 2008)

ELECTRICK2 said:


> Splatz, I am not suggesting more ground rods.
> There are no ground rods.
> 
> I suggest disconnecting ground from the water line
> ...


The thing is, if you have 10 feet or more of metal water line in contact with the earth, it MUST BE used as the grounding electrode, supplemented by rods.


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## eddy current (Feb 28, 2009)

Even if you pound more rods in and change the system ground, you still have to bond the metal water pipe to ground.
In my opinion, the only way to eliminate problem would be to pound new rods for new ground and isolate water pipe with plastic.


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## backstay (Feb 3, 2011)

The two houses are sharing a transformer. The second house has a high resistance ground. I suggest they try looking at the water heater. Could also be a nail stuck into a wire at the second house. Fix the grounding issues at the first house, then on to the second for more fun.


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## PlugsAndLights (Jan 19, 2016)

eddy current said:


> Even if you pound more rods in and change the system ground, you still have to bond the metal water pipe to ground.
> In my opinion, the only way to eliminate problem would be to pound new rods for new ground and isolate water pipe with plastic.


Ya, unless the place is already done in pex. 
P&L


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## ELECTRICK2 (Feb 21, 2015)

RePhase277 said:


> The thing is, if you have 10 feet or more of metal water line in contact with the earth, it MUST BE used as the grounding electrode, supplemented by rods.


 
It's a function of resistance. 
Your load is 6 amps.
Neutral resistance to pole is 0.1 ohm.
Resistance through water line to neighbors neutral is 0.2

What amperage would you expect on each neutral?


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## hardworkingstiff (Jan 22, 2007)

ELECTRICK2 said:


> The problem arises because we basically have a neutral bonded at 2 (Or more) points.


Every PoCo distribution system that I've seen is grounded often, kind of the "more" points you are talking about.

Adding more ground rods (or ground rods period) is just masking your problem.

This can easily be a PoCo neutral deterioration. which his a higher resistance back to the source (transformer), or like Splatz said, a problem in the transformer (but I would think not because I'm not so sure that would have the symptoms you are experiencing). Your symptoms (to me) sound like a high resistance path from the service neutral back to the source (transformer).


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## hardworkingstiff (Jan 22, 2007)

ELECTRICK2 said:


> I suggest disconnecting ground from the water line


I hope you don't do that.


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## ELECTRICK2 (Feb 21, 2015)

hardworkingstiff said:


> Every PoCo distribution system that I've seen is grounded often, kind of the "more" points you are talking about.
> 
> Adding more ground rods (or ground rods period) is just masking your problem.
> 
> This can easily be a PoCo neutral deterioration. which his a higher resistance back to the source (transformer), or like Splatz said, a problem in the transformer (but I would think not because I'm not so sure that would have the symptoms you are experiencing). Your symptoms (to me) sound like a high resistance path from the service neutral back to the source (transformer).


Why does code prohibit bonding at more than one point?


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## hardworkingstiff (Jan 22, 2007)

ELECTRICK2 said:


> Why does code prohibit bonding at more than one point?


They don't want parallel paths all over the place. 

The PoCo distribution system can be a killer (literally) if a high resistance neutral develops. Like aroud the ICW, the grounding at the substation is so good, the waterway is an excellent parallel path back to the substation source. Since the primary circuit and the secondary side of the transformers are referenced to earth (grounded), the main distribution neutral of PoCo's power can be a problem.


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## ELECTRICK2 (Feb 21, 2015)

backstay said:


> The two houses are sharing a transformer. The second house has a high resistance ground. I suggest they try looking at the water heater. Could also be a nail stuck into a wire at the second house. Fix the grounding issues at the first house, then on to the second for more fun.


 
Yes they share a transformer.
Neither has a high resistance ground. (They are joined via the water main)

One last try.
If I turn on a saw in house A, amperage on house A system ground goes up.
If I go to house B and turn on saw, amperage on house A system ground goes up.
This all makes sense, because our neutral is bonded in more than one place. 
I'm from Canada, but doesn't the US code say 1 bond only?


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## ELECTRICK2 (Feb 21, 2015)

hws, picture this.
You have 2 separate houses.

They each have a ground plate or rods.
Everything is fine.

Now, run a wire from one ground system to the other.
(Imitating the water main)

What do you think would happen?
All good or a bad idea?


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## RePhase277 (Feb 5, 2008)

ELECTRICK2 said:


> It's a function of resistance.
> Your load is 6 amps.
> Neutral resistance to pole is 0.1 ohm.
> Resistance through water line to neighbors neutral is 0.2
> ...


I'm not going to do the math, the point is that if a metal water line exists, it is a code requirement to be bonded to the neutral as a grounding electrode.

There is no getting around this current due to the code requirements. As long as the code requires this connection, there will be some current flowing on those pipes.


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## HackWork (Oct 2, 2009)

ELECTRICK2 said:


> I'm from Canada, but doesn't the US code say 1 bond only?


Inside the house. But neutral is also bonded to ground a few feet away inside of the meter pan. And at the pole. And at the neighbor's house. All the neighbors on the same tranny.

The water pipe GEC is the primary GEC and the most important. The ground rods are supplemental. Suggesting someone disconnect it should get you beaten senseless.


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## backstay (Feb 3, 2011)

ELECTRICK2 said:


> Yes they share a transformer.
> Neither has a high resistance ground. (They are joined via the water main)
> 
> One last try.
> ...


High resistance short between hot and ground, not enough to trip a breaker. I have seen this before. You turn off breakers until you find the circuit or circuits that are causing this. Then run down why. If you have current on the grounding electrode, you have a short somewhere.


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## Navyguy (Mar 15, 2010)

I have not read this, but was at an ESA meeting about a year ago and they now have a "team" of people to go out and investigate and repair this stuff. While this document seems older then what they were talking about, I suspect it is all the same in one way or another.
https://www.esasafe.com/assets/files/esaeds/pdf/ALL/Final%20Report%20-%20Ground%20Current%20Working%20Group.pdf

Cheers
John


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## hardworkingstiff (Jan 22, 2007)

ELECTRICK2 said:


> Yes they share a transformer.
> Neither has a high resistance ground. (They are joined via the water main)
> 
> *One last try.*
> ...


Seriously? "One last try"? 

Most of us understand this problem. It seems to me that you are trying to treat the "symptom" instead of finding the problem. I think you are the one that doesn't understand this problem.


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## chicken steve (Mar 22, 2011)

Your earthing system is* TN-C-S*, as is ours in (most of) the USA



> combined PEN conductor from transformer to building distribution point, but separate PE and N conductors in fixed indoor wiring and flexible power cords


earthing systems

The '_combined PEN_' includes every pole ground and poco Xformer XO back to the substation.

Mr Kirchoff's presence is _already_ apparent

Adding a municipal H20 system into this simply perpetuates it yet another _parallel path_ common to XO

Place an amp probe around any municipal mettalic H20 line, turn on any heavy load, and you'll most likely get the same effects you've already found

~CS~


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## 99cents (Aug 20, 2012)

Put an arc fault breaker on it.


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## chicken steve (Mar 22, 2011)

Further , most poco's are _well aware_ of this phenomenon . 

Most residents _are not_

However, it does become a problem for farms, farm animals, as well as farm watering ,feed & milking equipment.

The usual RX being to bond the living daylights out of anything and everything, as well as introducing earthing grid work.

The _fan dancy_ term being equopotential plane.

Literally a '_bird on a wire'_ fix.....

Many of such scenario's exist where this becomes less than effective, to the point where the poco can be solicited for an iso-xfomer. (_which they are equally aware of out in farm country)_

Now guess what happens if where to install 30-100ma RCD's as mains or sub mains on a TN-C-S? 
:001_huh:
How about a panel full of afci's ?
:001_huh:
have another cuppa, it'll sink in....
:yes:
~C(_sent with manure on my boots_) S~


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## PlugsAndLights (Jan 19, 2016)

Navyguy said:


> I have not read this, but was at an ESA meeting about a year ago and they now have a "team" of people to go out and investigate and repair this stuff. While this document seems older then what they were talking about, I suspect it is all the same in one way or another.
> https://www.esasafe.com/assets/files/esaeds/pdf/ALL/Final%20Report%20-%20Ground%20Current%20Working%20Group.pdf
> 
> Cheers
> John


Seems odd they investigate and repair when this is designed into the 
system and occurs at every transformer feeding more than 1 residence..
......which is every house in Ont and beyond.....

What are they going to do? Ground the transformer at the street and 
run a bond with each existing triplex? Unlikely. 

OK, just re-read this message, and it sounds like I'm attacking the 
messenger. Not my intent. 
P&L


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## ELECTRICK2 (Feb 21, 2015)

hardworkingstiff said:


> Seriously? "One last try"?
> 
> Most of us understand this problem. It seems to me that you are trying to treat the "symptom" instead of finding the problem. I think you are the one that doesn't understand this problem.


I'm not explaining this well at all.
I don't think there is anything wrong with the system.

Once the initial problem of the loose/corroded system ground connection was repaired everything worked as it was supposed to.
But as has been pointed out, there are several parallel paths for the neutral current to take. 
Every house adds one.

With all the extra paths for neutral current to take, a load in your neighbors house can put current on your system ground and neutral.

I was originally asking if it was dangerous.

Where I live you are no longer allowed to use the water line as a system ground. You must use ground rods or plates. The reason is the water lines are now insulated (To lessen the chance of freezing the line).


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## backstay (Feb 3, 2011)

ELECTRICK2 said:


> I'm not explaining this well at all.
> I don't think there is anything wrong with the system.
> 
> Once the initial problem of the loose/corroded system ground connection was repaired everything worked as it was supposed to.
> ...


None of the grounding electrode system is ment to be a return to the source. If you have current on it, something is wrong. If there was voltage to ground that shocked someone, there is something very wrong. Fixing the system ground didn't fix the problem.


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## hardworkingstiff (Jan 22, 2007)

backstay said:


> Fixing the system ground didn't fix the problem.


Agreed, and some people have a difficult time digesting that.


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## ELECTRICK2 (Feb 21, 2015)

I agree this much amperage on a system ground is not proper.
Which is why I posted it in the first place.

Put an amp meter on your system ground. If you and all your neighbors are tied into the same water line (All water lines metal and no plastics insulators to stop current)you will have neutral current on your system ground.


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## hardworkingstiff (Jan 22, 2007)

ELECTRICK2 said:


> I agree this much amperage on a system ground is not proper.
> Which is why I posted it in the first place.
> 
> Put an amp meter on your system ground. If you and all your neighbors are tied into the same water line (All water lines metal and no plastics insulators to stop current)you will have neutral current on your system ground.


If the wiring system is installed and operating properly (no high resistance splices in the neutral) then the parallel current will be in the ma range because of the difference in resistances of the water piping and the grounded conductor going back to the source. Having 4 amps on the grounding conductors is an indication of a high resistance neutral being developed.


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## sbrn33 (Mar 15, 2007)

backstay said:


> The two houses are sharing a transformer. The second house has a high resistance ground. I suggest they try looking at the water heater. Could also be a nail stuck into a wire at the second house. Fix the grounding issues at the first house, then on to the second for more fun.


is the second house having trouble?


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## ELECTRICK2 (Feb 21, 2015)

hardworkingstiff said:


> If the wiring system is installed and operating properly (no high resistance splices in the neutral) then the parallel current will be in the ma range because of the difference in resistances of the water piping and the grounded conductor going back to the source. Having 4 amps on the grounding conductors is an indication of a high resistance neutral being developed.


As I said before:
If
-your water line is copper,
-the main is metal
-there are no isolators involved
-you and your neighbor are using the water line as a system ground

Your system ground is low impedance.
Maybe not as low as the neutral because of the distance, but it won't be high.
And it will share the neutral current.

If your system ground is tied to a water line put an amp meter on it.
Might be zero, might not. Then plug in a saw and see what happens.


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## emtnut (Mar 1, 2015)

ELECTRICK2 said:


> As I said before:
> If
> -your water line is copper,
> -the main is metal
> ...


I know what your saying, and if the water piping between the 2 houses were copper, you actually would see the current you are talking about.... roughly a 1/3 (Just a guess)

In reality though, most mains on water systems are that light green PVC stuff. If it's a REALLY old neighbourhood, then it may be cast iron, but I don't think it has the low resistance that you think... if nothing else, because it's corroded to ratsh!t 

I've measured quite a few water pipes, and the current usually very small.

In this case, someone on the same transformer feeding this place has a problem.

In your case, when you fixed the ground clamp... all you did was set that potential to 'zero' ... current still flowing, but no one getting zapped.


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## HackWork (Oct 2, 2009)

ELECTRICK2 said:


> As I said before:
> If
> -your water line is copper,
> -the main is metal
> ...


Why will it share the neutral current?


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## hardworkingstiff (Jan 22, 2007)

ELECTRICK2 said:


> As I said before:
> If
> -your water line is copper,
> -the main is metal
> ...


Let's say you have a 100' lateral of 4/0 AL. Your overall resistance in the grounded conductor will be around 0.00608 ohms. If you get your water piping resistance down to 10 ohms, if the neutral is pulling 100 amps (highly unlikely) you would get a current divide of something like 99.9 amps through the grounded conductor and 0.1 amps through the grounding. Even if you got the ground resistance down to 1 ohm, the values barely change. So you see, the neutral has to start having a higher resistance in order for the grounding system to have 3-4 amps on it. 

There is a deteriorated neutral connection or the neutral conductor is compromised. 

If I plug in a saw and the current on the GEC goes up 4 amps, I'm going to start looking hard for that bad connection.


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## mitch65 (Mar 26, 2015)

bad neutral connection at the transformer that the neighborhood shares. Ground electrodes are the easiest path home. closer you are to the transformer, the higher the current you will see on the your ground


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## PlugsAndLights (Jan 19, 2016)

emtnut said:


> I know what your saying, and if the water piping between the 2 houses were copper, you actually would see the current you are talking about.... roughly a 1/3 (Just a guess)
> 
> In reality though, most mains on water systems are that light green PVC stuff. If it's a REALLY old neighbourhood, then it may be cast iron, but I don't think it has the low resistance that you think... if nothing else, because it's corroded to ratsh!t
> 
> ...


I know that you know more about city plumbing than I do, but I'm still 
buying the parallel path explanation. Fact is none of us know what his 
local street plumbing is. Also, now and then when hooking up the system
gnd I'll lightly brush it against the incoming plumbing pipe first and 
usually see sparks. 
P&L


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## emtnut (Mar 1, 2015)

PlugsAndLights said:


> I know that you know more about city plumbing than I do, but I'm still
> buying the parallel path explanation. Fact is none of us know what his
> local street plumbing is. Also, now and then when hooking up the system
> gnd I'll lightly brush it against the incoming plumbing pipe first and
> ...


If standing on top of dug up ditches, watching .. then I'm an expert :laughing:

It's definetly a parallel path, but I don't see the current he measured to be possible unless someone's neutral is open/high resistance.
It would be an awesome parallel path, if it was copper between the 2 houses, which it isn't/

As far as the sparks on the water clamp, I've seen that too. I'm not qualified to say what power is required... I don't think it takes much to make that spark though.
I always thought of that the same as sparking a 9V battery.

.... Unless the sparks start welding for you !

Interested to see what others say.


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## ELECTRICK2 (Feb 21, 2015)

emtnut said:


> I know what your saying, and if the water piping between the 2 houses were copper, you actually would see the current you are talking about.... roughly a 1/3 (Just a guess)
> 
> In reality though, most mains on water systems are that light green PVC stuff. If it's a REALLY old neighbourhood, then it may be cast iron, but I don't think it has the low resistance that you think... if nothing else, because it's corroded to ratsh!t
> 
> ...


If the main is PVC what I'm talking about doesn't happen.
If it's cast iron and corroded enough to be high impedance and not carry current it probably ain't carrying water either.


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## emtnut (Mar 1, 2015)

ELECTRICK2 said:


> If the main is PVC what I'm talking about doesn't happen.
> If it's cast iron and corroded enough to be high impedance and not carry current it probably ain't carrying water either.


That's why everyone was on the 'bad system neutral' somewhere :thumbsup:


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## ELECTRICK2 (Feb 21, 2015)

HackWork said:


> Why will it share the neutral current?


Because it is a parallel path back to the source.
Let's say you have 150 feet of a large (10"?) metal plumbers pipe between the houses.
And 30 feet of copper from each house to the main.
Let's say your neutral to the pole is 50 feet.
Although longer, the water lines do offer a second path back to the pole.

It's like if you have a light bulb that draws 1 amp.
Your neutral will of course have the same 1 amp on it.
Add a second neutral that has twice the length of the first one.

Original neutral should have .666 of an amp.
New neutral should have .333 amps

It all depends on the resistance of the water lines.
In my case judging by the readings I get, the resistance is low.


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## ELECTRICK2 (Feb 21, 2015)

I asked a guy I work for to check the amps on his system ground.
He lives in the same area as the first house, 4 or 5 blocks away.

He has 1.5 amps on his system ground.
So I will go to his place tomorrow and see...


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## backstay (Feb 3, 2011)

All this parallel neutral crap is BS in this case. The guy got shocked, if the grounding was poor then little or no path. This is a case of hot to ground current flow because of a short that is not low enough impedance to trip the breaker.


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## hardworkingstiff (Jan 22, 2007)

backstay said:


> All this parallel neutral crap is BS in this case.


I don't how you can come to that conclusion since he said the current went up after he put a load on it. If it was a high resistance short between a hot and ground, the current should be constant and not act like the OP said.


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## readydave8 (Sep 20, 2009)

ELECTRICK2 said:


> Where I live you are no longer allowed to use the water line as a system ground. You must use ground rods or plates. The reason is the water lines are now insulated (To lessen the chance of freezing the line).


I don't think I understand. Metal pipe with thermal insulation?


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## backstay (Feb 3, 2011)

hardworkingstiff said:


> I don't how you can come to that conclusion since he said the current went up after he put a load on it. If it was a high resistance short between a hot and ground, the current should be constant and not act like the OP said.


How do you get shocked from a open ground? In a correctly operating 120/240 volt system, I can open the GECs and not suddenly get voltage on the panel grounds.


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## hardworkingstiff (Jan 22, 2007)

backstay said:


> How do you get shocked from a open ground? In a correctly operating 120/240 volt system, I can open the GECs and not suddenly get voltage on the panel grounds.


If the service neutral is compromised (cable or connection) then more current passes on the parallel path that the GEC is connected to. If one was to disconnect that GEC under these conditions, you will have a difference of potential between that opened connection. As long as the neutral is good, you won't get any shock.


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## backstay (Feb 3, 2011)

hardworkingstiff said:


> If the service neutral is compromised (cable or connection) then more current passes on the parallel path that the GEC is connected to. If one was to disconnect that GEC under these conditions, you will have a difference of potential between that opened connection. As long as the neutral is good, you won't get any shock.


But all the OP did was make the ground connection better. That didn't fix the problem. He didn't have a bad neutral. He had a bad ground. The current is still flowing.


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## hardworkingstiff (Jan 22, 2007)

backstay said:


> But all the OP did was make the ground connection better. That didn't fix the problem. He didn't have a bad neutral. He had a bad ground. The current is still flowing.


I believe his neighbor has the bad neutral. The current is coming through the neighbors GEC connection to the water piping system and then back through this property's GEC connection to the water piping system and back to the source (the shared transformer) through this property's neutral conductor.


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## backstay (Feb 3, 2011)

hardworkingstiff said:


> I believe his neighbor has the bad neutral. The current is coming through the neighbors GEC connection to the water piping system and then back through this property's GEC connection to the water piping system and back to the source (the shared transformer).


So the problem is still there.


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## hardworkingstiff (Jan 22, 2007)

backstay said:


> so the problem is still there.


oh yea!


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## emtnut (Mar 1, 2015)

ELECTRICK2 said:


> If the main is PVC what I'm talking about doesn't happen.
> If it's cast iron and *corroded enough to be high impedance and not carry current it probably ain't carrying water either*.


Didn't notice this till now. Underground pipes like these, because the earth around them has been 'compacted' into shape, they can actually be pretty much corroded, and the water still gets pumped through ... trust me, I've seen it many times !

I tried to google the conductivity of cast iron ... no luck.
Pure Iron only has 17% conductivity compared to copper ... and cast iron would be significantly lower than that.... and that's assuming it isn't corroded ... 

So you may see small amounts of current on the water pipe ... but NO WAY would it jump to 4 amps by plugging in something at the neighbours.

Take a look back at what Hardworkingstiff and others said :thumbsup:


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## 51360 (Jun 9, 2014)

eddy current said:


> Even if you pound more rods in and change the system ground, you still have to bond the metal water pipe to ground.
> In my opinion, the only way to eliminate problem would be to pound new rods for new ground and *isolate water pipe with plastic.*


Yes. Isolate the municipal water system from the home's water piping system. 

As explained in *Appendix B regarding Rule 10-902,* some municipalities do *NOT* allow the municipal water system to be used as a ground electrode. For very very good reason! 

Also, there will always be some current on the grounding electrode in most residential systems, even if the neutral is well connected. As already mentioned, parallel paths is a fact. 

For my business, it has been standard practice for the past several years, to measure current on the system grounding electrode periodically and note the pertinent variables. Especially before I make major alterations, or there is a problem. :thumbsup:

Wait till we start using the earth to transmit power! 

Borgi


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## emtnut (Mar 1, 2015)

Borgi said:


> For my business, it has been standard practice for the past several years, to measure current on the system grounding electrode periodically and note the pertinent variables. Especially before I make major alterations, or there is a problem. :thumbsup:
> 
> Borgi


Can you share some of your results ?

I'd be interested in some of the average current readings you get, and if you have seen a difference between ground rods only vs water pipe grounding.
Or any other of the pertinent variables you have noted.


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## varmit (Apr 19, 2009)

In some of the previous posts there was a suggestion to disconnect GEC from the water pipe and drive ground rod(s) at the first house.. This would create a worse hazard, as the apparently energized water pipe from the neighbors is still in the first house house. There would probably be a considerable difference of potential between the non bonded water line and anything bonded to the first house service.

A possibly more safe option would be to replace a section of the metal water line, before it enters the house, with a section of plastic pipe. Repair the bonding of the interior water piping in the first house and install ground rod(s).

As long as nothing conductive is touching or reachable between both houses, this should lessen the problem. Yes there would be the potential for some current through the earth, but this should be minute.


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## backstay (Feb 3, 2011)

varmit said:


> In some of the previous posts there was a suggestion to disconnect GEC from the water pipe and drive ground rod(s) at the first house.. This would create a worse hazard, as the apparently energized water pipe from the neighbors is still in the first house house. There would probably be a considerable difference of potential between the non bonded water line and anything bonded to the first house service.
> 
> A possibly more safe option would be to replace a section of the metal water line, before it enters the house, with a section of plastic pipe. Repair the bonding of the interior water piping in the first house and install ground rod(s).
> 
> As long as nothing conductive is touching or reachable between both houses, this should lessen the problem. Yes there would be the potential for some current through the earth, but this should be minute.


The right thing to do is fix the problem, not mask it.


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## 51360 (Jun 9, 2014)

Borgi said:


> Yes. Isolate the municipal water system from the home's water piping system.
> 
> As explained in *Appendix B regarding Rule 10-902,* some municipalities do *NOT* allow the municipal water system to be used as a ground electrode. For very very good reason!
> 
> ...


Noticed a wee grammatical error in my post. When I say there is always some current on the* "grounding electrode"*, I meant current on the *"grounding conductor"* used to connect the system to the ground electrode. My apologies, but I think you got the idea. 

I measure the current in that conductor. The *"grounding conductor"*. Sometimes I have to work at it, but usually you can safely access the* "grounding conductor"* if you simply remove the cover.

Results are exactly what you would expect! Try it. :thumbsup:

Borgi


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## EJPHI (May 7, 2008)

Replaced the service and just for fun, I measured the ground current from the water pipe to the panel:

180 mA!! Clamp on current probes rock.

I don't think this is a problem because the whole neighborhood shares some neutral current on the ground.


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## hardworkingstiff (Jan 22, 2007)

emtnut said:


> Can you share some of your results ?
> 
> I'd be interested in some of the average current readings you get, and if you have seen a difference between ground rods only vs water pipe grounding.
> Or any other of the pertinent variables you have noted.


I would love to see all of us put an ampmeter on the GEC whenever we are around a service and report back here the reading. I think it would be interesting to see the results. Maybe it should be a new thread?


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## hardworkingstiff (Jan 22, 2007)

EJPHI said:


> Replaced the service and just for fun, I measured the ground current from the water pipe to the panel:
> 
> 180 mA!! Clamp on current probes rock.
> 
> I don't think this is a problem because the whole neighborhood shares some neutral current on the ground.


I think if we had a bunch of readings we would find `180ma to be in the "normal" range.


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## chicken steve (Mar 22, 2011)

It doesn't even need to get _that_ technical Borgi....

I have many times tapped an* arc *via H2O pipe GEC on a bus bar in front of apprentices 

Then asked them _why _it exists....

~CS~


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## lighterup (Jun 14, 2013)

hardworkingstiff said:


> They don't want parallel paths all over the place.
> 
> The PoCo distribution system can be a killer (literally) if a high resistance neutral develops. Like aroud the ICW, the grounding at the substation is so good, the waterway is an excellent parallel path back to the substation source. Since the primary circuit and the secondary side of the transformers are referenced to earth (grounded), the main distribution neutral of PoCo's power can be a problem.


Currently working on an old house / partial remodel. 
Where I have been able to stick my head up into the ceiling and
see , I have found a half dozen soldered points where a knob & tube
neutral has been connected to copper water line.
I first started looking for this because anytime my hole hawg 
would bumb into a water or cast iron plumbing , I nice healthy
ARC (not ARCH or ARK he-he-he) would take a chunk of steel
out of my hole hawg casing.

Agree with you ...this is what happens when more than one
bonding point is going on.


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## chicken steve (Mar 22, 2011)

Happens all the time in commercial & industrial , where multiple Xformers (_trade slang & no, i'm not sorry_) have XO connected to building steel of H20 Lighter dude.*

The whole structure is a *noodle *(_not sorry there either_):no:

All the cred card machines, freq drives, and plc's go haywire, the power quality EE's are called on in, etc etc , _ad nauseam_

~C_(arcin' and barkin_')S~


* M.E.N.


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## varmit (Apr 19, 2009)

backstay said:


> The right thing to do is fix the problem, not mask it.


I agree, but you would have little to no leverage to force a neighbor to fix their problem. So trying to make your own home safe as practical would be the next best option.


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## telsa (May 22, 2015)

varmit said:


> I agree, but you would have little to no leverage to force a neighbor to fix their problem. So trying to make your own home safe as practical would be the next best option.


A jacked up neutral will cause so much grief that the neighbor will be well motivated to cure his own Service.


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## chicken steve (Mar 22, 2011)

Or.....one could shut down his system, disco the noodle, and watch his neighbor fry all his 120 stuff.....~CS~


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## telsa (May 22, 2015)

chicken steve said:


> Or.....one could shut down his system, disco the noodle, and watch his neighbor fry all his 120 stuff.....~CS~


That'd be a chicken #### move, no doubt.


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## 51360 (Jun 9, 2014)

chicken steve said:


> *It doesn't even need to get that technical* Borgi....
> 
> I have many times tapped an* arc *via H2O pipe GEC on a bus bar in front of apprentices
> 
> ...


I record everything, and keep pretty decent records because I am, as my sister's call it, ............well, it's not an nice word.

Like most ECs, I have come across some crazy weird problems over the years, and it's nice to have documentation. Maybe I'll write a book when I retire. :jester:

Borgi


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## HackWork (Oct 2, 2009)

Borgi said:


> I record everything, and keep pretty decent records because I am, as my sister's call it, ............well, it's not an nice word.


Homofag? Doosh bagel? Fecal stew?


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## 51360 (Jun 9, 2014)

As I was typing the word anal, I recalled the *Ron White skit,* where one of his wive's said she was "anal". Ron said, "right on", but he was a wee bit confused! :jester:

Taking meticulous notes, whatever you call it, is a good habit to be afflicted with. :thumbsup:

Better than my other vices! 

Borgi


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## MechanicalDVR (Dec 29, 2007)

Borgi said:


> As I was typing the word anal, I recalled the *Ron White skit,* where one of his wive's said she was "anal". Ron said, "right on", but he was a wee bit confused! :jester:
> 
> Taking meticulous notes, whatever you call it, is a good habit to be afflicted with. :thumbsup:
> 
> ...


I was a note taker/keeper for years, it paid off many times over.

I prefer to call myself OCD, it sounds so much cleaner than 'anal'.


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## telsa (May 22, 2015)

MechanicalDVR said:


> I was a note taker/keeper for years, it paid off many times over.
> 
> I prefer to call myself OCD, it sounds so much cleaner than 'anal'.


It's also less Freudian, too.


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## PlugsAndLights (Jan 19, 2016)

Clamped one today, got .6A.
P&L


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## RePhase277 (Feb 5, 2008)

chicken steve said:


> It doesn't even need to get _that_ technical Borgi....
> 
> I have many times tapped an* arc *via H2O pipe GEC on a bus bar in front of apprentices
> 
> ...


No, you got a *spark *, NOT an arc. Dr. Paschen would tell you this if he could.


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## emtnut (Mar 1, 2015)

hardworkingstiff said:


> I would love to see all of us put an ampmeter on the GEC whenever we are around a service and report back here the reading. I think it would be interesting to see the results. Maybe it should be a new thread?


I think that's a good idea !

If you guys do that, It would be interesting to say whether there is water pipe, rods, or both.

I'd expect slightly higher readings from anywhere that has very wet soil conditions, but we'll see if we get enough readings !


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## ELECTRICK2 (Feb 21, 2015)

backstay said:


> How do you get shocked from a open ground? In a correctly operating 120/240 volt system, I can open the GECs and not suddenly get voltage on the panel grounds.


Exactly my point.
What was open was not exactly a system ground conductor but a secondary neutral path.


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## ELECTRICK2 (Feb 21, 2015)

I have taken readings at our shop; system ground is ground rods.
0 amps on the system ground.
Plugged in saw to make sure load was unbalanced; still zero.

Took reading at my house; ground rods again.
0 amps; saw plugged in still zero.

The 2 houses I know are tied to a water line have current on system ground
I asked a few days ago, if you are tied on to a water line take a reading.


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## ELECTRICK2 (Feb 21, 2015)

backstay said:


> But all the OP did was make the ground connection better. That didn't fix the problem. He didn't have a bad neutral. He had a bad ground. The current is still flowing.


And if you remember, it is flowing both ways.
I plug in a saw in house A, current on house A system ground goes up.

I plug the same saw into an outside receptacle on house B
Current goes up on house A system ground.

How does a bad neutral on house B or A make this happen in both cases?


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## ELECTRICK2 (Feb 21, 2015)

emtnut said:


> I think that's a good idea !
> 
> If you guys do that, It would be interesting to say whether there is water pipe, rods, or both.
> 
> I'd expect slightly higher readings from anywhere that has very wet soil conditions, but we'll see if we get enough readings !


I would predict any readings taken on a system with ground rods or plates
Would be less than an 1/2 an Amp.

Readings taken on a system that uses the water line as a ground and the main is isolated or plastic would be the same.

Readings taken on a system that has a continuous conductive path from one house to another will vary greatly depending on the load.


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