Bonding to water system

[wilsonelectric]

I am currently upgrading an old 60A service to a 100A service in Michigan. The current ground system is as follows: (1) driven ground rod( encased in cement)with a #6 AWG bare to the 60A panel. The house does not have a basement(located on a cement slab) and I have been unable to locate a water meter to bond around. I have asked the homeowner to call his local utility to get a location on the meter, if it even exists, and whether it is copper or plastic. If I am understand the code correctly, if the incoming line is plastic, I should be able to drive (2) ground rods six feet apart and then bond to the closest water line. If it is metal, I am required to bond within 5 feet of entrance into the home.I appreciate any help.

 

[tonyi]

Re: Bonding to water system

If there's a metal water main, it'll be your primary electrode (get on it within 5' of entry), with the rods supplementing. Supplementals can be tapped (not spliced) onto the GEC coming from a metal water main.

If there's no metal main or other buried metal piping/conduit, then two rods, bond inside plumbing and you're done. Might want to also put a jumper across hot/cold on an electric water heater too. Dialectric unions and plastic nipple seats on newer setups won't be conductive.

Look around for any buried piping or conduit going to anything outside too, a garage feeder, outside lights, etc. If there's any buried metal conduit or maybe an old galvanized pipe to garage water, buried oil tank piping or stuff like that, then it becomes part of the GES too.

 

[tom baker]

Re: Bonding to water system

"If there's a metal water main, it'll be your primary electrode (get on it within 5' of entry), with the rods supplementing."
This is allowed by 250.52 only if there is ten feet of the metallic underground water line in contact with the earth. If not, a bonding connection is still made to the water line per 240.104. An acceptable grounding electrode is still required per 250.52 and it may end up being 1 or 2 driven electrodes.

 

[tonyi]

Re: Bonding to water system

I doubt Michigan soil conditions would support single rod use. In most cases, I can't see it being worth bothering to measure - do two and there's never a question.

 

[rrrusty]

Re: Bonding to water system

I have found H2O meters out in the alley buried with a access pipe so in that case just bond where the H2O comes into the house; contact UFPO for a locate and follow the blue lines and you may find your meter

 

[wilsonelectric]

Re: Bonding to water system

Thanks for the help. I located the water meter in a front closet, about 80' from the service panel. I am considering running the GEC through the top of the closet, through the attic, and into the new panel. (The home has no basement). Now, another question. I am planning on driving 2 ground rods, with a #4 AWG GEC (local utility company require a min of #5 AWG). The problem Is there is 3" of concrete all around where I would normally drive the ground rods. Is this case, is it acceptable to put the ground round further away, approximately 25'at the front or rear of the house and run the GEC through the garage to the panel. I will break up the concrete if I need to, but if another way is acceptable, I would appreciate it. I can not find any references to GEC distances in the NEC at all. Everyones support is very much appreciated.

 

[ryan_618]

Re: Bonding to water system

You can put the electrode (rod) wherever you like. The important thing is that the grounding electrode conductor goes to the proper place in the premises wiring system.

One thing you might consider is hammer drilling a 3/4 hole into the concrete to drive your rod. I see this done quite often.

 

[Guest]

Re: Bonding to water system

Ryan_618 said:

One thing you might consider is hammer drilling a 3/4 hole into the concrete to drive your rod. I see this done quite often.

Wondering about 250.53(G): How do we do this if the surface material is hardscaping?

[ September 29, 2003, 04:29 PM: Message edited by: awwt ]

 

[earlydean]

Re: Bonding to water system

Wayne,
The supplemental electrode MAY be a ground rod. If it is infeasable to use a ground rod, then we must choose another type of supplemental ground. We could install a plate, or chip down to some rebar. Whatever it takes.

Earl

 

[ryan_618]

Re: Bonding to water system

Originally posted by awwt:
]Wondering about 250.53(G): How do we do this if the surface material is hardscaping?

Wayne, which part of 250.53 (G) are you refering to? (G) lists a few different requirements. Can you be more specific? Thanks

 

[Guest]

Re: Bonding to water system

I'm wondering about the actual mechanics of doing it. Driving it to full depth. Having any exposed portions protected. Having 8' in the ground. 25-Ohms. I literally am asking how we do it so it can pass code. I want to know the proper way to accomplish a ground rod in hardscaping. Let's say it's a 5/8" ground rod with #4 bare solid and an Acorn connector-- or other connector or protection.