# Multifamily Grounding



## Dennis Alwon (May 9, 2009)

I guess the responses in Mike Holt forum was not enough.

As I mentioned over there the gas pipe does not need a #6 if there is some piece of gas equipment that is wired. The egc for that circuit even if it is a #12 is enough for the bond. Sprinklers should not be bonded as far as I know based on fire codes.


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## Magnettica (Jan 23, 2007)

Dennis Alwon said:


> I guess the responses in Mike Holt forum was not enough.
> 
> As I mentioned over there the gas pipe does not need a #6 if there is some piece of gas equipment that is wired. The egc for that circuit even if it is a #12 is enough for the bond. Sprinklers should not be bonded as far as I know based on fire codes.


Are you saying that NFPA 72 supersedes 250.104 (A)(1)?


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## MDShunk (Jan 7, 2007)

I think it does, but the reality is that the jockey pumps and dry system compressors will bond it.


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## brian john (Mar 11, 2007)

MDShunk said:


> I think it does, but the reality is that the jockey pumps and dry system compressors will bond it.


 
And in a concrete building all the anchors in the concrete (some always hit rebar) other metal touching the piping and a million other accidental grounds.


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## Dennis Alwon (May 9, 2009)

brian john said:


> And in a concrete building all the anchors in the concrete (some always hit rebar) other metal touching the piping and a million other accidental grounds.



I am not sure but I had heard that the sprinklers have a dielectric fitting where it enters the building. Is that true? If so then what difference does it make if it is bonded?


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## brian john (Mar 11, 2007)

Dennis Alwon said:


> I am not sure but I had heard that the sprinklers have a dielectric fitting where it enters the building. Is that true? If so then what difference does it make if it is bonded?


 
The big issue as I see it would be if it were truly ungrounded, totally isolated and an energized conductor fell on the piping the sprinkle system would be energized.


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## MDShunk (Jan 7, 2007)

Dennis Alwon said:


> I am not sure but I had heard that the sprinklers have a dielectric fitting where it enters the building. Is that true? If so then what difference does it make if it is bonded?


Much of the sprinkler piping nowadays is assembled with Victaulic fittings. They're darned near dielectric. You might as well say it's got a dielectric fitting at least every 21 feet.


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## Dennis Alwon (May 9, 2009)

MDShunk said:


> Much of the sprinkler piping nowadays is assembled with Victaulic fittings. They're darned near dielectric. You might as well say it's got a dielectric fitting at least every 21 feet.


Boy, that would be fun to have to bond around everyone of those fitting on a high rise or commercial building. :no:

I was thinking that just wanted a dielectric fitting so the pipe was not used as a grounding electrode.


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## brian john (Mar 11, 2007)

MDShunk said:


> Much of the sprinkler piping nowadays is assembled with Victaulic fittings. They're darned near dielectric. You might as well say it's got a dielectric fitting at least every 21 feet.


Yeah that sure has changed the skill level of fitters, when I was an apprentice they had to be decent at welding and threading. Last job I saw it was 95% prefab.


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