# Proper grounding of a 3 family dwelling.



## Dennis Alwon (May 9, 2009)

There are many ways so how about you tell us what you are planning to do.

BTW, welcome to the forum


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## Magnettica (Jan 23, 2007)

$9800


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## BurtiElectric (Jan 11, 2011)

Dont you need a Masters License to work in MA?


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## backstay (Feb 3, 2011)

I'd use wire to ground with. That's the way I do it most of the time.


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## EBFD6 (Aug 17, 2008)

BurtiElectric said:


> Dont you need a Masters License to work in MA?


No, you can pull permits with a journeyman license in MA. You can also employ 1 apprentice. There are many guys that run their own business with nothing more than a journeyman license.

A master's license allows you to hire journeymen, and you can have 1 apprentice for every journeyman license you employ. Job ratios are 1:1 also.

You actually can not work with the tools with only a master's license. If you have a master's license you still have to hold a journeyman's license to do work.


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## EBFD6 (Aug 17, 2008)

jdawg523 said:


> I'm gonna be changing a friends service which is a 3 family house. I'll be adding a fourth panel as a house panel. I'll also be running a 200 amp line to a 4 gang meter socket then inside feeding 4 panels 100 amp main with a number 2 Seu. I'm almost 100% sure how to properly ground inside an out but I'd perfer to check with other electricians to be sure. Haven't done residensual in a few years. Please let me kno what u all think as to the grounding. Thanks


Drive 2 rods and run GEC to meter socket. Bond metal piping systems and anything else you have that is required. Pretty basic. Depending where your panels are located you probably need 4 wires from meters to panels with mains in meter socket.


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## McClary’s Electrical (Feb 21, 2009)

EBFD6 said:


> Drive 2 rods and run GEC to meter socket. Bond metal piping systems and anything else you have that is required. Pretty basic. Depending where your panels are located you probably need 4 wires from meters to panels with mains in meter socket.


 
Many power companies won't allow a GEC in the meter base.


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## EBFD6 (Aug 17, 2008)

mcclary's electrical said:


> Many power companies won't allow a GEC in the meter base.



Not an issue in Massachusetts, which is where the OP is from


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## jdawg523 (Mar 5, 2012)

Dennis Alwon said:


> There are many ways so how about you tell us what you are planning to do.
> 
> BTW, welcome to the forum



Lol

Well I plan on obv using ground rods to meters. An inside I'm obv jumping out water main an then bringing #4 to closes water pipe an off that #4 I'm putting ground bar above panels an bringing #6 I believe to each panel. Someone work with said I had to run a separate # from water pipe to meter sockets. Never heard about that before. Unless I can do that instead of having ground rods? It's a city house so I barely have room for one ground rod anyway. Let me kno what u think.


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## RIVETER (Sep 26, 2009)

mcclary's electrical said:


> Many power companies won't allow a GEC in the meter base.


Do you know why they won't allow it?.That GEC would protect the building if the poco had a short circuit problem at THEIR service transformer...or lightning for that matter.


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## RePhase277 (Feb 5, 2008)

RIVETER said:


> Do you know why they won't allow it?.That GEC would protect the building if the poco had a short circuit problem at THEIR service transformer...or lightning for that matter.


Some don't allow it because they tag their meters and don't want you in there. If your ground wire is in there, you might need access to it.

On the flip side, some POCOs won't have the ground any other place but the meter socket. So.... it's best to check with them first.


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## Dennis Alwon (May 9, 2009)

If you have a 4 gang meter base and the water lines are connected together than you can run a #4 copper gec to the water pipe with 5' of where it enters the building-- assuming it is metal pipe entering the building. You will also need 2 rods spaced at least 6 feet apart unless you can show 25 ohms from one rod-- I doubt you can.


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## Magnettica (Jan 23, 2007)

If the OP is using the water pipe as an electrode, he must bring the #4 cu to within 5' of where it enters the building, not to "closes water pipe." And we can assume this because he plans to supplement this set up with a pair of ground rods. 



> 250.52 Grounding Electrodes.
> (A) Electrodes Permitted for Grounding.
> (1) Metal Underground Water Pipe. A metal underground
> water pipe in direct contact with the earth for 3.0 m
> ...


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## magneticpersona (Apr 28, 2012)

usually when i do a service I use a buried ground plate with a #6awg copper to the panel. Also I bond the water piping and gas lines as per CSA standards.


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## mark35 (Mar 24, 2009)

Dennis, if you could clear this up for me. We've discussed in the past, for example, a single family 400a service that would consist of a meter with two 200a mains that in turn feed two 200a MLO panels. 31015(B)(6) is not used to size the feeder that runs between the main and the panel, we both agree on this. The op has a multifamily installation and is wiring it in a very similar fashion as I have described above. The op will be using, I assume, #2 AL se, to feed the 100a panels. Now, because this is a multfamily dwelling one can use 310.15(B)(6) to size the sub feeders?


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## mark35 (Mar 24, 2009)

Never mind Dennis, I figured it out.


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