amps on h2o line

[greenjeans]

I'm having a problem with a 200 amp heavy up i installed in august.
while finishing up the service up grade, i reconnected the #4 CU GEC to the 3/4" cu h2o line ( had been disconnected by previous owner and never reconnected) the new owners had no idea what it was when they painted the garage wire and pipe. so it never sparked on them. cleaned up the CU pipe and wire, put a new h2o GND clamp on and when i connected the GEC, sparks!!
once installed, i metered the #4 CU and found 6 Amps on the line, but my service was not energized yet so i called the local PWR company and requested them to meter the 9 homes being serviced by the xformer.they checked all the lines and said it was fine. i said its not fine, request #2 . talked to two supervisors, said they understood the problem and would fix it. no-go, said was no problem, NOW WHAT!! homeowner wants the problem fixed and so do i, however she doesn't want me to charge her for the time spend on this problem. its not my problem, what do i do??? it seems so simple to fix. meter all 9 homes neutrals and hots and find the one that doesn't add up, notify that home owner, tell them theres a problem with their service --they wont do it , even after #3 request and local inspector wont get involved any ideas???

[iwire]

There is likely no problem at all, considering the power company already checked it out I would forget about it.

6 amps on the water line is no big deal or surprise.

The metal underground water line is in parallel with all the other homes neutrals, even if everyones neutral is perfect there will be current on the water line.

[mdshunk]

All those homes on that transformer also share the same underground metal pipework, in all likelihood. Everything sounds normal to me too. Kirchoff's Law.

[brian john]

If you'd like to resolve the issue install a die-electric coupling ((insulated coupling). BUT you must keep the water pipe GEC except it is now the water pipe bond, and you must install new electrodes, which you most likely did when you installed the new service.

[mdshunk]

Originally Posted by brian john

If you'd like to resolve the issue install a die-electric coupling ((insulated coupling). BUT you must keep the water pipe GEC except it is now the water pipe bond, and you must install new electrodes, which you most likely did when you installed the new service.

I think that would solve the "problem", but I'm struggling with how to make that legal. If it's metal pipe coming in, you need to use it. If you install a dielectric coupling, now you have to bond the inside pipework. After you bond the interior pipework and hit the water pipe as a GEC, you've just defeated the dielectric coupling.

[suemarkp]

Put the coupling outside, not inside. I would think anywhere outside is fine, if the goal is to make sure your metal pipes aren't touching your neighbors metal pipes. You'll still get some current on the pipes because of the ground electrodes, but at least it is earth coupled and no longer hard piped.

[iwire]

Originally Posted by brian john

If you'd like to resolve the issue install a die-electric coupling ((insulated coupling).

Originally Posted by mdshunk

I think that would solve the "problem", but I'm struggling with how to make that legal.

I agree with Marc, for an EC to do that....eliminate a 'present' electrode...is an NEC violation.

If an electrode is present we must use it.

Originally Posted by suemarkp

Put the coupling outside, not inside. I would think anywhere outside is fine, .

That might be an idea if you place it outside beyond 10' from the house you would have still isolated it and you would still have the original water pipe electrode.

Now that said, is there any evidence that we should even be concerned with this current on the water piping system?
There are literally millions of these water pipes with current on them and they seem to be working fine.

[megawatt]

This has always been a sore spot with Me. I have never liked interconnected grounds via the water line.
I don't have a problem wiith bonding the metal water pipes INSIDE the residence, but too often a lost / poor neutral connection from house A is never noticed because it is being carried thru the metal undergroung piping to the properly grounded neutral in home B.
This is sometimes found by an unsuspecting Handyman, Plumber, or Home owner when they cut, or break the water pipe connection. Not often, but sometimes a deadly result.
We have probably all heard of stories where a plumber has been electrocuted while changing out a hot water tank, or laying under a house repairing a leak, but I seem to remember an article where a gasoline explosion was caused by such a spark while making a plumbing repair.
I think the grounging & bonding systems should stop at the foundation. Then when home A has a neutral / grounding issue it will be only at that location.
Plastic from the meter to the house !

[George Stolz]

Originally Posted by iwire

I agree with Marc, for an EC to do that....eliminate a 'present' electrode...is an NEC violation.

If an electrode is present we must use it.

IMO, if a dielectric coupling is installed 1" from the exterior of the basement wall, there is no longer a grounding electrode present that is required to be used. I don't see a prohibition from 'destroying' an electrode to escape the requirement to use it, literally speaking.

Originally Posted by iwire

That might be an idea if you place it outside beyond 10' from the house you would have still isolated it and you would still have the original water pipe electrode.

I agree, that's a really good idea, especially if the tap is accessible out at the street to do it without any digging.

Originally Posted by iwire

Now that said, is there any evidence that we should even be concerned with this current on the water piping system?
There are literally millions of these water pipes with current on them and they seem to be working fine.

I don't think we have any electrical problems, but doesn't it corrode the piping over time? I forget whether that was truth or fiction, it could have been shot down by a report or something, it's been a while since this was discussed.

[tom baker]

Originally Posted by brian john

If you'd like to resolve the issue install a die-electric coupling ((insulated coupling). BUT you must keep the water pipe GEC except it is now the water pipe bond, and you must install new electrodes, which you most likely did when you installed the new service.

This is the method recommended by the American Water Works Association.
They state that one meter reader (water) a day is shocked by working on a "hot meter".