water meter related service shocks

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Does anyone have any examples of injuries,incidents, or safety practices related to removal,replacement, installation or maintenance of water meters or related to issues arising from replacement of copper water service with non-conductive materials?
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
Occupation
retired electrician
The only time there should be a shock hazard is where the service grounded conductor is open or a high impedance path. If the grounded conductor is in good shape, you may get an arc when opening the water pipe, but there should not be a shock hazard.
Don
 

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
If this is an ongoing concern, maybe the plumber should carry a wide-jaw clamp-on ammeter.

The direct answer is that the water piping should never act as the grounded conductor, so breaking that pathway should have little to no effect.

If a hazard deveopes, there already was a hazard waiting to rear its ugly head. Suprises like this suck.
 

hockeyoligist2

Senior Member
This reminds me of my childhood. Old house built in 1896 was wired and plumed sometime later. It was in the 60's, then, and every time you turned on the outside water you got a tingle, If you were barefoot or touching something, you would almost mess up your pants! I am so surprised, now that I know the dangers, that I didn't get electrocuted!

That is one of the reasons why I don't touch anything now until I check it!

Murphy's Law, I'll probably bump something hot tomorrow!
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
Occupation
retired electrician
Larry,
The direct answer is that the water piping should never act as the grounded conductor, so breaking that pathway should have little to no effect.
In a code compliant installation in a area served by common underground metal water pipes, up to 25% of the grounded conductor current will flow on the water pipe. When you open the pipe there will be a small arc, but as long as the service grounded conductor is in good shape there will not be a shock hazard. The voltage that dives the arcs is equal to the voltage drop on the service grounded conductor. Now take this same code compliant installation where there is a problem with the service neutral. The water pipe is the neutral and you will have the full line to ground voltage when you open the pipe. If you open the pipe in this case, not only do you have a shock hazard, but you have created an open neutral which may result in equipment damage of even a fire in the building.
Don
 

tom baker

First Chief Moderator
Staff member
The american water works association (AWWA) states that one water meter reader gets a shock every day from working on a hot meter, in my experience from an open neutral.
If you go to the AWWA web site they have more information and a position paper on grounding electrical services to water lines.
The AWWAs recommendation is to install a short length, 6", of non metallic pipe in the metal service lines. This is only a concern with metallic water service lines, since the 70's water companies have been using plastic water service lines.
If the water service line is replaced with plastic the plumbing code requires a notice to be placed on the electrical panel stating that.
 

MikeMc

Member
Cannot find it

Cannot find it

Can you provide the article name? I searched the AWWA website for a while and could not find anything on the topic. An URL or link would help too.
 
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