Continious service ground?

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dduffee260

Senior Member
Location
Texas
When you install a service ground wire in a dwelling it goes to the footing, the cold water pipe, if the pipe is copper then to a ground rod.
Some people say this ground wire needs to be one continious piece from the ground rod to the panel ground bar or whatever route you install it. Some say it is ok to cut the wire as long as it is attached to a device that is suitable or listed for splicing the ground wire. Such as the ground bar on the panel or some type of ground lug. This means you have to thread the ground clamps or lugs over the wire then reattach the clamps, lugs, bars, etc. back to the attachment points.
What is your intrepetation of this? Can you take a listed ground lug and cut the wire then go two different ways? Does continious mean from point to point or not cut in any way?
 

roger

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Location
Fl
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Retired Electrician
Only the GEC needs to be continuous, all other connections are simply bonding jumpers.

1113918256_2.jpg


Roger
 

infinity

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Location
New Jersey
Occupation
Journeyman Electrician
Roger is correct. The only required continuous conductor is the GEC, which would go to the water pipe. As shown in his graphic the other connections would be bonding jumpers which can connect to other electrodes without being continuous. Also I would note that if you have a connection to a concrete encased electrode the ground rod is not required.
 

Ragin Cajun

Senior Member
Location
Upstate S.C.
I have a pet peeve regarding this whole issue. Take, for example the picture in Roger's reply. I assume it is from the code handbook. In my professional, biased, hard headed opinion, this is a lousy scheme to provide a secure grounding electrode system. For all practical purposes, the picture is using the stupid water pipe to connect between the service and the rebar. Then, it uses the rebar to connect the rest of the various grounding electrodes together.


This stinks!

To me all the grounding electrodes should tie together to a copper conductor or to a common point and not indirectly via water pipes, rebar, etc.

I would like to show a picture of an ACAD block I use to show what I like, but it?s on another computer at another location. Maybe tonight I can put it on a zip drive and post it tomorrow.

Am I off base here??!!

Raging Cajun (Now you know the reason for my user ID)
 

petersonra

Senior Member
Location
Northern illinois
Occupation
engineer
Ragin Cajun said:
I have a pet peeve regarding this whole issue. Take, for example the picture in Roger's reply. I assume it is from the code handbook. In my professional, biased, hard headed opinion, this is a lousy scheme to provide a secure grounding electrode system. For all practical purposes, the picture is using the stupid water pipe to connect between the service and the rebar. Then, it uses the rebar to connect the rest of the various grounding electrodes together.


This stinks!

To me all the grounding electrodes should tie together to a copper conductor or to a common point and not indirectly via water pipes, rebar, etc.

You seem to be making an assumption that bonding all these things together serves any useful purpose in the first place.
 

infinity

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Location
New Jersey
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Journeyman Electrician
Ragin Cajun said:
I
To me all the grounding electrodes should tie together to a copper conductor or to a common point and not indirectly via water pipes, rebar, etc.

I would like to show a picture of an ACAD block I use to show what I like, but it?s on another computer at another location. Maybe tonight I can put it on a zip drive and post it tomorrow.

Am I off base here??!!

Raging Cajun (Now you know the reason for my user ID)


You are off base if the requirement is to be within the framework of the NEC. The requirement is for a grounding electrode system. The GEC goes to the water pipe if present and the rest of the system simply gets connected together. This is what the NEC requires. Now, what you like may be completely different, but if it goes beyond Roger's graphic, it's not required.
 

bphgravity

Senior Member
Location
Florida
Electricians tend to over think the GES. I know I think about them just about everyday...

More emphasis should be placed on other protective techniques such as TVSS and other surge protection devices. This is the future of electrical systems. Grounding concepts and techniques cannot advance beyond the point they are today. No product or method of grounding will ever be any better than the very first telegraph line grounded in the late 1800's.
 

jwelectric

Senior Member
Location
North Carolina
Attached are two pictures of the grounding electrode conductor and the system bonded together.
First is from the 2005 Handbook and second is from the IAEI 2005 Analysis.

The main thing is to leave the panel with a conductor sized from Table250.66 and hit all the others with a conductor of the proper size.

Example;
Leave the panel with a conductor sized from Table 250.66 and hit a driven rod. Leave the rod with #4 and hit the CEE.

What would be incorrect and I have seen this done is to leave the panel with #6 and hit the rod and then leave the rod and hit the CEE.
 

infinity

Moderator
Staff member
Location
New Jersey
Occupation
Journeyman Electrician
jwelectric said:
Attached are two pictures of the grounding electrode conductor and the system bonded together.
First is from the 2005 Handbook and second is from the IAEI 2005 Analysis.

The main thing is to leave the panel with a conductor sized from Table250.66 and hit all the others with a conductor of the proper size.

Example;
Leave the panel with a conductor sized from Table 250.66 and hit a driven rod. Leave the rod with #4 and hit the CEE.

What would be incorrect and I have seen this done is to leave the panel with #6 and hit the rod and then leave the rod and hit the CEE.


If you have a CEE why would you have a rod?
 

jwelectric

Senior Member
Location
North Carolina
infinity said:
If you have a CEE why would you have a rod?

It was just an example. I could (should) have said water pipe, steel, ect.

And to add just a little information, if both the CEE and rod are present both would have to be used. Let?s say that I did a room addition to a house that already had a rod and installed rebar to the new footing wouldn't both be required?

In the example where I stated that I have seen the rod hit with a #6 and then a #6 run to the rebar. Why they did this I do not know unless it has to do with the misconception of the Electrode Conductor is required to be continuous between the two.
 

infinity

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Location
New Jersey
Occupation
Journeyman Electrician
It was just an example. I could (should) have said water pipe, steel, ect.

And to add just a little information, if both the CEE and rod are present both would have to be used. Let?s say that I did a room addition to a house that already had a rod and installed rebar to the new footing wouldn't both be required

That a good point Mike. That is unless they want to try and pull out the rod!
 

Lady Engineer

Senior Member
Location
New Jersey
To me, it doesn't seem like it would matter how you connected them together.... meaning looped or branched off...as long as there's one common point to ground. I don't see the differenct. That's like taking all your branch circuits and making sure they are dasy chained.

Is this a cost savings issue?

That's JMHO! ;)


Lady :)
 

iwire

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Staff member
Location
Massachusetts
Ragin Cajun said:
In my professional, biased, hard headed opinion, this is a lousy scheme to provide a secure grounding electrode system. For all practical purposes, the picture is using the stupid water pipe to connect between the service and the rebar. Then, it uses the rebar to connect the rest of the various grounding electrodes together.


This stinks!

Not to me. :)

I take advantage of it.

A 3000 amp service I did was about 200 or 300 feet from the water service.

I went 30' vertical from the service with a GEC to building steel than put a bonding jumper from building steel to the water service.

Saved the labor and materials for a 200' to 300' run.

I do not consider it poor practice or hack work.
 
From Bob
" 3000 amp service I did was about 200 or 300 feet from the water service.

I went 30' vertical from the service with a GEC to building steel than put a bonding jumper from building steel to the water service.

Saved the labor and materials for a 200' to 300' run.

I do not consider it poor practice or hack work."


Actually this is far from hack work. In todays environment one needs to be as cost effective and still provide a good job. The above concept is in my opinion both.
It actually shows a great understanding of the concept.
 

George Stolz

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Location
Windsor, CO NEC: 2017
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Service Manager
Ragin Cajun said:
This stinks!
Do you think it stinks from a "connection to earth" standpoint, or do you dislike that disconnection of one jumper can remove several electrodes? I didn't notice you elaborate about what aspect of it you dislike.

Raging Cajun (Now you know the reason for my user ID)
Ha! That didn't hold a candle to one of my bitter, pointless diatribes! :D :D
 

hillbilly

Senior Member
This is a interesting subject. Just the other day I got a call from a (new) customer. This young couple are moving from out of state into a older home they just purchased. The lady said that her lights dimmed (and blinked) when she ran her disposal. Upon investigation (actually the first thing that I checked), I discovered that the ground conductor on the service drop had corroded and broken in two. The GEC ran from the breaker panel to the (galvanized) water line. Apparently the return current was going thru the water line, down the street and thru the neighbors plumbing before returning through the neighbors electrical system. I looked up the number for the POCO and stood by while they called for immediate repair. The POCO came pretty quickly and the problem was resolved. There was a plumber working under the house when I arrived! I called him out and advised him to stop work until the problem was corrected. He turned pale and said that he was getting ready to work on the water line. I hate to think what would have happened if I hadn't shown up when I did.
I wonder (although I won't ask) if the neighbors had noticed anything un-usual going on (electrically) in their home?
I don't know if using the water line for the electrode is such a good idea if the water line is continuous metal between different homes.
steve
 

charlie tuna

Senior Member
Location
Florida
consider this situation:
a 1200 amp - 480 service feeding a school. the electrical contractor wired the service ground as shown on the plans -- two driven ground rods and the cold water pipe ---- and they were joined on the service neutral bus. the electrical room was next to the power company's vault. in this case the power company wired the customer's neutral conductors (3 - 500mcm cu.) by mistake to the vault's ground bus. this ground bus's only connection back to the secondary transformer was a #2 wire. for years this #2 wire carried this service unbalanced load. then came a phase to phase fault when the contractor himself -- dropped his nextel phone into the back of the service panel. the first explosion caused the #2 wire in the vault to blow in half. now-- ask yourself where the fault current goes next. the driven ground rods and water pipe did little --- the phase to phase fault continued to explode for over twenty minutes melting the service distribution panel and burned the service phase condutors back into the vault until they got close enough to the transformer's neutral to cause the primary overcurrent devices to trip. a fireman told me that when they drove up the jacks on the overhead pole were smoking! i beleive the ground rods and the water pipe were carrying some current -- but not enough to cause the overloads to open. the real low impedance path in this case was the neutral service conductors which were isolated when the #2 wire blew in half....
 

Ragin Cajun

Senior Member
Location
Upstate S.C.
Pierre C Belarge said:
From Bob
" 3000 amp service I did was about 200 or 300 feet from the water service.

I went 30' vertical from the service with a GEC to building steel than put a bonding jumper from building steel to the water service.

Saved the labor and materials for a 200' to 300' run.

I do not consider it poor practice or hack work."


Actually this is far from hack work. In todays environment one needs to be as cost effective and still provide a good job. The above concept is in my opinion both.
It actually shows a great understanding of the concept.


Not saying that's a hack job. What else could you do?

I have a similar problem with apartment buildings I do. The water is nowhere near the electrical service.

I just don't like using a water line as a connection between things. Too big a risk of loosing a connection.

I still will get my detail for you guys to see, haven't had time.
 
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