Grounding on services

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ddubbs103

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Massachusetts
Just wondering if you guys could give me a hand on grounding electrodes for a service residential and commercial. Everyone I ask gives me a different answer and after reading some stuff here most of them have not a clue, or they just like to be told what to do and not learn anything. I am from MA and I'm really not sure even after reading art 250. Just curious about if ground rods have to be in or outside or both, do you have to connect to the meter or can you go ground rods to water pipe to panel etc. I'm just wondering how some of you guys do it thanks for any information you can give me, I really enjoy reading posts etc from electricians that take pride in what they do. Happy New Year.
 
ddubbs103 said:
Just curious about if ground rods have to be in or outside or both, do you have to connect to the meter or can you go ground rods to water pipe to panel etc. I'm just wondering how some of you guys do it
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Grounding and bonding are very misunderstood topics, so I'm not surprised that you've gotten conflicting information. You've come to the right place for the right answers. :)

The NEC is silent about the location of ground rods - so they can be inside or out. Sometimes you have no choice but to put them inside, and vice versa.

Some power companies allow the GEC (the conductor between the grounding electrode(s) and the service disconnect or equipment) to be connected inside the meter can, and others do not. You have to check your local poco spec book (the "Green Book") to see what they allow.
 
ddubbs103 said:
Just wondering if you guys could give me a hand on grounding electrodes for a service residential and commercial. Everyone I ask gives me a different answer and after reading some stuff here most of them have not a clue, or they just like to be told what to do and not learn anything. I am from MA and I'm really not sure even after reading art 250. Just curious about if ground rods have to be in or outside or both, do you have to connect to the meter or can you go ground rods to water pipe to panel etc. I'm just wondering how some of you guys do it thanks for any information you can give me, I really enjoy reading posts etc from electricians that take pride in what they do. Happy New Year.
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Is not the Local AHJ have info on this?? I know i can contact the local AHJ and they have booklets on how they want things done.

As far as the Nec is concerned , and the way Ive seen/and have done it here in RESIDENTIAL is you drive 2 8ft ground rods at least 6ft apart installed OUTSIDE of course. a Bare copper #6 wire is ran continuous(meaning NO SPLICES) from the ground buss in the service panel to these ground rods attached to them with grd clamps..

A #4 copper wire is ran from the NEUTRAL buss in the service panel and connected to the METAL cold water pipe within 5 ft of the water pipe entering the building (house). The neutral buss and ground buss in the service panel is bonded to together with a jumper (this is suppose to help clear a ground fault.) The meter can is relying on the neutral from the service overhead as its bond so NO additional grounding is needed there. Im told that its different in OTHER areas where you do attach the meter to the ground rods in addition to the service panel even though its attached to the service neutral. Check with your local AHJ for additional connections in the meter can. The #4 copper wire and #6 cooper wire is sized according to the tables 250.66 (GEC) and 250.122 (EGC) respectively. So if yours is a bigger or smaller sevice entrance conductor and over current protection device (breaker) then your sizes would be different.

In Commercial, it depends, sometimes there is building structural steel, grounding ring, or water pipe or rods you install or both. Basically, if a GE (grounding electrode) is there you have to USE it, if not you have to INSTALL ONE and connect to it.

You might want to order some of Mike Holts books that actually show the PICTURES and illustration that shows how this is done. Im told that they are good ive never used them before but have seen some of the pictures. Also ask your AhJ to give you pictures. PICTURES are worth a THOUSAND words. ;) Hopes this helps.
 
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brother said:
As far as the Nec is concerned , and the way Ive seen/and have done it here in RESIDENTIAL is you drive 2 8ft ground rods at least 6ft apart installed OUTSIDE of course. a Bare copper #6 wire is ran continuous(meaning NO SPLICES) from the ground buss in the service panel to these ground rods attached to them with grd clamps..
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Although I wire the ground rods as you do the #6 does not need to be unbroken. You can go from the meter or main panel to the first rod and then use another piece of #6 to jumper between the 2 rods.
 
You can also go GEC to ground rod to water pipe. But there is a little detail to watch. Ground rods only require a #6 wire regardless of the service conductor size. However, water pipes must have a full size bonding wire sized per 250.66.

So if you go panel to rod to pipe, you need a full sized conductor the whole way. If you go panel to pipe to rod, you use a full size GEC to the pipe, and a #6 to the rod. But there is one more gotcha -- the GEC can not be spliced, so if the water pipe is not a legal electrode (is not metal in the earth for 10' or more, and you're just bonding it not using it as an electrode) then you can't splice at the water pipe to go to the ground rod.

Confused yet?
 
brother said:
Is not the Local AHJ have info on this?? I know i can contact the local AHJ and they have booklets on how they want things done.
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That's fine as long as what how the AHJ "wants things done" is in the NEC or local amendments.

brother said:
a Bare copper #6 wire is ran continuous(meaning NO SPLICES) from the ground buss in the service panel to these ground rods attached to them with grd clamps..
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The GEC only has to be continuous to the first rod. After that, you can add a second clamp and a jumper between the two rods. And a 100 amp service only needs to be #8 to the ground rods. (I mention that because 100 amp services are still very common in MA.) The GEC can be bare, covered, or insulated.



brother said:
A #4 copper wire is ran from the NEUTRAL buss in the service panel and connected to the water pipe within 5 ft of the water pipe entering the building (house).
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The #4 is fine for a 200 amp service, but a 100 amp service would only require a #8.
 
peter d said:
The #4 is fine for a 200 amp service, but a 100 amp service would only require a #8.
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Probably when contractors were installing 60 amp services in houses years back, they thought that was more than the occupants would ever need.

Because 100 to 200 amp service upgrades are popular, I build my 100 amp services with #4 to the water line. Reason being, the "path" from the service equipment to the required water line connection point often disappears. That is to say, the path often becomes highly finished, such that fishing an upsized GEC in the future will be near impossible to accomplish in a non-objectionable way. For the cost difference, running a #4 water line GEC on 100 amp services often seems like the thing to do for me. It may well make the guy's life easier 30 years from now when he's changing from 100 amp to 200 amp.

Just my opinions.
 
On of the guys I worked with said he goes from his ground rods outside to his meter, then he goes from his water pipe to the panel ?. So with the full size gec from the panel to the water pipe what type of connection would you use to go from there to the ground rods, a typical pipe clamp?. Ive just heard so many answers and get confused when I try to understand it, thanks for the advise and any more to follow.
 
peter d said:
That's fine as long as what how the AHJ "wants things done" is in the NEC or local amendments.



The GEC only has to be continuous to the first rod. After that, you can add a second clamp and a jumper between the two rods. And a 100 amp service only needs to be #8 to the ground rods. (I mention that because 100 amp services are still very common in MA.) The GEC can be bare, covered, or insulated.





The #4 is fine for a 200 amp service, but a 100 amp service would only require a #8.
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I thought i made that PLAIN in my post

brother said:
As far as the Nec is concerned , and the way Ive seen/and have done it HERE in RESIDENTIAL ......
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brother said:
Check with your local AHJ for additional connections in the meter can. The #4 copper wire and #6 cooper wire is sized according to the tables 250.66 (GEC) and 250.122 (EGC) respectively. So if yours is a bigger or smaller sevice entrance conductor and over current protection device (breaker) then your sizes would be different.
Click to expand...
 
brother said:
I thought i made that PLAIN in my post
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Generally, when you say how the AHJ "wants things done" it implies his own personal preference that's not found in the NEC. That is usually how that gets interpreted around the forum. I'm sorry for any misunderstanding.
 
peter d said:
Generally, when you say how the AHJ "wants things done" it implies his own personal preference that's not found in the NEC. That is usually how that gets interpreted around the forum. I'm sorry for any misunderstanding.
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Ok no problem. I suppose the Ahj's im use to dealing with tend to be a little more professional. They are willing to give a 'code' reference for any violation they point out or anything they say how they want it done, whether it be NEC, Or local ammendments. Only once in a while do i run into or hear about a 'difficult' inspector. Sounds like you guys may run into it more.
 
mdshunk said:
Probably when contractors were installing 60 amp services in houses years back, they thought that was more than the occupants would ever need.

Because 100 to 200 amp service upgrades are popular, I build my 100 amp services with #4 to the water line. Reason being, the "path" from the service equipment to the required water line connection point often disappears. That is to say, the path often becomes highly finished, such that fishing an upsized GEC in the future will be near impossible to accomplish in a non-objectionable way. For the cost difference, running a #4 water line GEC on 100 amp services often seems like the thing to do for me. It may well make the guy's life easier 30 years from now when he's changing from 100 amp to 200 amp.

Just my opinions.[/QUO
Except for real estate flips,I'll only offer 150 amp services and up.
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boboelectric said:
Except for real estate flips,I'll only offer 150 amp services and up.
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So be it.

I'm not sure if I've ever built a 150 amp service in my life. The material, for me, is actually more expensive for a 150 versus a 200.
 
mdshunk said:
The price of the panel, for the main reason. A panel with a 150 amp main is not so cheap compared to a 200.
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Wow you guys get to 'BUILD' your own panel. Here in my area, we have a 'CITY CODE' that when you do a panel change it MUST be a 200 AMP service upgrade minimal in a residential. So no 150 or other wise. and of course the UL listing, so no 'BUILDING' your own.
 
brother said:
Wow you guys get to 'BUILD' your own panel. Here in my area, we have a 'CITY CODE' that when you do a panel change it MUST be a 200 AMP service upgrade minimal in a residential. So no 150 or other wise. and of course the UL listing, so no 'BUILDING' your own.
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Too bad for you. The rest of us live in the rest of the country.
 
ddubbs103 said:
On of the guys I worked with said he goes from his ground rods outside to his meter, then he goes from his water pipe to the panel ?. So with the full size gec from the panel to the water pipe what type of connection would you use to go from there to the ground rods, a typical pipe clamp?. Ive just heard so many answers and get confused when I try to understand it, thanks for the advise and any more to follow.
Click to expand...


Most guys around here do the same.

Use what is called an "Acorn" clamp on the rods water pipe clamp on the water pipe.
 
brother said:
Bare copper #6 wire is ran continuous(meaning NO SPLICES) from the ground buss in the service panel to these ground rods attached to them with grd clamps..

A #4 copper wire is ran from the NEUTRAL buss in the service panel and connected to the METAL cold water pipe within 5 ft of the water pipe entering the building (house). The neutral buss and ground buss in the service panel is bonded to together with a jumper (this is suppose to help clear a ground fault.)
Click to expand...

Most residential service panels do not have separate ground and neutral busses so the GEC's would both terminate on the same buss.


brother said:
The #4 copper wire and #6 cooper wire is sized according to the tables 250.66 (GEC) and 250.122 (EGC) respectively. So if yours is a bigger or smaller sevice entrance conductor and over current protection device (breaker) then your sizes would be different.
Click to expand...

There will no EGC required between the meter and the service panel. What EGC are you referencing?
 
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