City water network creates parallel neutrals (parallel conductors)

[EMFExplorer]

A number of us have been bringing this issue to light for some time. When a home or other building is connected to city water via copper water supply pipe, and the electrical service is bonded to this pipe, the pipe becomes a secondary neutral current-carrying conductor. Rather than just be present in the temporary event of a fault, it is actually a current-carrying conductor that is operating 24/7/365.

It is my opinion this is very inappropriate and actually violates sections of the NEC. Yet it is also required. I think the code should be updated, and it should be standard practice to electrically isolate the city water network and only use ground rods or other electrodes. When we interconnect all buildings via the water, we create countless paths for circuit current to take that are NOT along the appropriate path - the intended circuit current-carrying conductors - wherein the current should be confined. Using pipes for carrying circuit current should be prohibited.

 

[roger]

Metallic water systems are becoming rare so not much of a concern anymore but here is an illustration to go with your post.


Please update your profile to include a little more accurate location.

 

[roger]

BTW, instead of changing the NEC why not make it mandatory for plumbing codes to install a dielectric connection to the house. Even if the NEC removed the requirement to use the metallic water piping as part of the GES it would still be connected due to inside bonding be it purposely or accidental.

 

[infinity]

Most commercial buildings still use metal water piping systems. Maybe an isolated section of non-metallic pipe at the entry into the building would work. Even in doing so couldn't the water itself still carry some current?

 

[Fred B]

Rogers description very accurate with a high level current on the metal pipe due to an open neutral.
Lower, fluxtauting current, on the grounding system indicative of the NEV presence related to utility multi-grounded systems. Even eliminating metal pipe or isolation device would not eliminate the NEV coming onto the individual structures gounding system.

 

[EMFExplorer]

Most commercial buildings still use metal water piping systems. Maybe an isolated section of non-metallic pipe at the entry into the building would work. Even in doing so couldn't the water itself still carry some current?

I have a very sensitive clamp meter that detects "leaking" current - PM me if you'd like info. It goes down to .01 milliamps. So far I have never measured current through water (in a pex/cpvc pipe). Obviously it depends on the situation, but it certainly could happen if the voltage were high enough and the impedance of the water were low enough. But in real practice I have never seen it go through water.

I have frequently, however, seen small amounts of current making it through dielectric unions. These unions aren't the most reliable devices. I prefer a piece of pex pipe.

 

[Fred B]

You show occupation as EMF. What exactly is your occupation initials mean?

 

[EMFExplorer]

Rogers description very accurate with a high level current on the metal pipe due to an open neutral.
Lower, fluxtauting current, on the grounding system indicative of the NEV presence related to utility multi-grounded systems. Even eliminating metal pipe or isolation device would not eliminate the NEV coming onto the individual structures gounding system.

While some of the current would be NEV, some of the current on a water pipe where it enters the buildings will be primary and secondary neutral current from onsite, nearby transformers, and nearby buildings. Well...I can't really say "nearby" either since this stuff can travel very far. But basically that pipe becomes part of countless circuits in the area, small amounts of current from all of these various circuits are present.

So portions of the secondary neutral current from other buildings is there, a portion of the secondary neutral current from the buildings you're at, and a portion of primary neutral current from transformers as well. I want to say that would be the bulk of it - primary and secondary neutral current. You are correct that there is NEV current as well - there always has to be since current takes all paths. But the NEV current will be the smallest I think in most situations compared to the primary/secondary neutral currents. I base this off of the readings changing dramatically when onsite loads change and loads change in nearby buildings as well. So perhaps we could even say most of it is secondary neutral current?

Either way it's regular circuit current - not fault current - and we're allowing it to travel on pipes.
As for NEV current - this can be considerably reduced when utilities run appropriately-sized neutrals and ensure all of their connections are good. Small wire and poor connections result in greater impedance and so more of the current will flow through pipes and earth - mostly on the surface of the earth. It is a real problem, and a real problem that of course has a known a proven solution. They just don't want to spend the money on doing it.

 

[Fred B]

the bulk of the current on a water pipe where it enters the buildings will be primary and secondary neutral current from onsite, nearby transformers, and nearby buildings.

A properly operating and installed system should not be putting any primary/secondary current onto the GES of a structure. If it is, then a fault condition is existing that needs to be addressed and repaired such as the open neutral referenced by Roger. Typically on a properly opperating and installed system the only current presence on the GES would be NEV, that is resulting from utility multigrounded system, and the Electrician has little to no control of.

 

[EMFExplorer]

A properly operating and installed system should not be putting any primary/secondary current onto the GES of a structure. If it is, then a fault condition is existing that needs to be addressed and repaired such as the open neutral referenced by Roger. Typically on a properly opperating and installed system the only current presence on the GES would be NEV, that is resulting from utility multigrounded system, and the Electrician has little to no control of.

I beg to differ. When measuring the current on a water pipe entering a building, the current will greatly, greatly fluctuate depending on the loads onsite. Turn some 120 volt loads on/off and the numbers dramatically change. This shows it the change in secondary neutral current. And why wouldn't it be there? It is a low-impedance path. Not only onsite secondary neutral current but offsite secondary neutral current as well - they change as your neighbors turn on and off 120 volt loads too. They also change with primary neutral current.

There wouldn't be as much fluctuation if it were all NEV current.

 

[Speedskater]

Gee, I consider it a good feature of an all metal neighborhood all metal water pipe system. It keeps the Neutral potential very close to Earth's.
I sometimes wonder what happens when part of the system is replaced with plastic. The century homes near me, don't have other connections to Earth. Do minor 'Lost Neutral' problems cause other issues?

 

[Fred B]

Your descriptions are indicative of an open neutral on someones system, for there to be high current changes. The open neutral, when you have multiple structures that are interconnected via a GES, intentional or nonintentional (common water pipe) connection, will try to find the lowest impedence return path and that can be throught the interconnected metal waterpipe system to a good (intact) neutral. (See Rogers post #2) This is not a natural occurance but a situation of a faulty installation somewhere with the interconnected structures. If your waterpipe is the lowest impedance return path it will use "it" vs a higher impedance.

Again, what is EMF occupation?

 

[roger]

Again, what is EMF occupation?

It appears he's talking about Electro Magnetic Fields

He should have been here when Karl Riley was an active participant.

 

[EMFExplorer]

Your descriptions are indicative of an open neutral on someones system, for there to be high current changes. The open neutral, when you have multiple structures that are interconnected via a GES, intentional or nonintentional (common water pipe) connection, will try to find the lowest impedence return path and that can be throught the interconnected metal waterpipe system to a good (intact) neutral. (See Rogers post #2) This is not a natural occurance but a situation of a faulty installation somewhere with the interconnected structures. If your waterpipe is the lowest impedance return path it will use "it" vs a higher impedance.

Again, what is EMF occupation?

Current doesn't "try to find the lowest impedence (sic) return path". Current takes all paths all the time. Kirchhoff's rules. 1 amp is 6,240,000,000,000,000,000 electrons flowing past a plane in 1 second. That's a lot of electrons that can spread amongst many paths.

I've measured this secondary and primary neutral current on more pipes than I could even estimate. Thousands. So it is very much the norm to see the fluctuations as loads turn on/off. It is not due to a fault. It is just due to how electricity works and when you give it multiple low-impedance paths the current splits significantly.

Yes, EMF refers to electromagnetic fields. Karl is well-known for his work in finding and fixing wiring errors. I wish more electricians would take the time to use an EMF meter and/or clamp around a romex cable to check for a reading. Too many neutral-to-ground and neutral-to-neutral connections that shouldn't be taking place - and violate the NEC too by-the-way.

 

[Little Bill]

Yes, EMF refers to electromagnetic fields. Karl is well-known for his work in finding and fixing wiring errors. I wish more electricians would take the time to use an EMF meter and/or clamp around a romex cable to check for a reading. Too many neutral-to-ground and neutral-to-neutral connections that shouldn't be taking place - and violate the NEC too by-the-way.

He is asking what your occupation is in the field.

 

[rambojoe]

Id like to know what primary neutral current at the utility transformer is...

 

[EMFExplorer]

I own a company - it's listed in my profile (I was told not to "advertise" here) - that measures, finds wiring errors, consults, etc relating to EMF/EMR. We find a lot of NEC violations such as neutrals of multiple circuits connected together, neutral-to-ground at subpanels and other boxes/appliances, inadvertent NG shorts, and such. These issues cause huge magnetic fields in the environment.

 

[Fred B]

Current doesn't "try to find the lowest impedence (sic) return path".

That is true, but it will return based on impedence of each path with more allocated toward the lower impedence in ratio to the impedence of each.

I wish more electricians would take the time to use an EMF meter and/or clamp around a romex cable to check for a reading.

Have seen and repaired resulting faulty wire found via EMF. Most related to improper connection or K&T wiring. Seen it soo bad my ticker going of in the middle of a room. Got rid of the bad K&T and poorly installled NM and got rid of it and the customer's ghosts.

He is asking what your occupation is in the field.

Not sure of the OP but I'm not a ghost hunter, I'm an electrician. Most everyone I've seen around here walking around with a gauss meter are ghost hunters.

 

[EMFExplorer]

Id like to know what primary neutral current at the utility transformer is...

neutral current on the primary side of the transformer? What's your question?

 

[don_resqcapt19]

A properly operating and installed system should not be putting any primary/secondary current onto the GES of a structure. If it is, then a fault condition is existing that needs to be addressed and repaired such as the open neutral referenced by Roger. Typically on a properly opperating and installed system the only current presence on the GES would be NEV, that is resulting from utility multigrounded system, and the Electrician has little to no control of.

A common metal underground water pipe is a parallel path for the service neutral conductor....it is not uncommon to find 20% or more of the neutral current flowing on the water pipe.