Grounding

[resistance]

My question: Is there any reason why I can't jump my #4 grounding conductor from my non-service rated (Sub-panel) panel---looking at NEC 250.64(B)(3)?? I thought in the case of the article mentioned, we should be fine! Any input would be greatly appreciated.

 

[celtic]

NEC 250.64(B)(3)??

What year is that?....no (3) in '99, '02 or '05

 

[resistance]

Sorry, I meant 250.64(C)(3) 2005

 

[infinity]

Could you provide some more detail? I'm not sure that we understand your question.

 

[resistance]

OK! Instead of jumping a #4 Bare copper from my meter main to the cold water pipe, I would like to jump it from the sub-panel to the cold water pipe. Q: Is there any reason why this wouldn't be permissible. I thinking it would be fine looking at Art: 250.64(C)(3). Just wondering! <<A grounding conductor was ran in conduit with my sub-feed, from the meter main to the sub-panel.

Thanks.

 

[JohnJ0906]

I cant find the exact article right now, but no, you cant. It should come from the service main. If the subpanel was removed at some future date, you would no longer be bonded.

 

[JohnJ0906]

found it-250.104(A)(1).

 

[resistance]

Really! Hum, I wonder! Why are we allowed to splice from a "bus bar" located in an accessible space, but not utilize a bus bar on an acessible sub-panel. I guess I'm asking this question because of exactly what John is stating!

I'll wait more comments.

Thanks John!

 

[bphgravity]

Are you talking about grounding your electrical service or bonding the service to interior metal water pipe?

 

[George Stolz]

I'd say, if you were so inclined, you could run a GEC to a subpanel, and then run a bonding jumper to the electrodes. You would still need to run a GEC from the service to the busbar, per 250.24(A)(1) and 250.64(C)(3).

Not to steal Bryan's thunder, but if the water pipe in question is not eligible as a grounding electrode per 250.52(A)(1), then it must be bonded in accordance with 250.104. The funny thing is, that bonding conductor is not allowed to utilize the busbar, if I'm reading 250.104 correctly.

JMO,

 

[bphgravity]

Not to steal Bryan's thunder...

You can steal my thunder; just don't take my precious lightning!

 

[cripple]

Gorunding

Gorunding

The code requires the metal water piping systems to be bonded to service equipment enclosure, the grounded conductor at the service, the grounding electrode conductor where of sufficient size, or to the one or more grounding electrodes used. The only options you would have are laid in 250.104.
Section 25.64(C)(3) does permit the use of an aluminum or copper busbar not less than
1/ 4 in. thick by 2 in. wide. This busbar can be used to terminate bonding jumper(s) from grounding electrode(s) and grounding electrode conductor(s). The connection shall be by a listed connector or by the exothermic welding process. I feel the busbar in the sub-panel would not met the requirement called out in 250.64(C)(3).

 

[resistance]

Are you talking about grounding your electrical service or bonding the service to interior metal water pipe?

Yes, But not the main service. Just wondering. Sorry I got back so late, I've been working late hours---trying to finish-up the work I started to meet new work schedules!!! Heck, I've been spending my social time with rats under a 3 foot high crawl space for the last four days<<<<had to run 40 feet of conduit to a non-service rated panel. No option but to crawl!!

Thanks for the feed back.

 

[George Stolz]

Resistance, "Yes" is not a helpful response to an "either/or" question.

Section 250.64(C)(3) does permit the use of an aluminum or copper busbar not less than 1/ 4 in. thick by 2 in. wide. ... I feel the busbar in the sub-panel would not met the requirement called out in 250.64(C)(3).

I believe the busbar could be 1/4 wide by 2" long, which most subpanel grounding bars would comply with.

Most grounding bars are listed by the manufacturers of the panels they reside in.

I don't see what section would prevent it's use for the purpose outlined in 250.64(C)(3).

You can steal my thunder; just don't take my precious lightning!

LOL

 

[Gmack]

Resistance, "Yes" is not a helpful response to an "either/or" question.


I believe the busbar could be 1/4 wide by 2" long, which most subpanel grounding bars would comply with.

Most grounding bars are listed by the manufacturers of the panels they reside in.

I don't see what section would prevent it's use for the purpose outlined in 250.64(C)(3).


LOL

No, this situation/OP is not acceptable.

250.24 [A] [5] read FPN also.

Imagine if this service is/could be installed larger than its sub as described.

In addition to that, the GEC must be connected at the service.

It cannot originate at a sub panel busbar and hitch a ride back on a load side feeder neutral.

And you certainly cant jumper from the EG busbar either.

It has to originate at the service GC.

 

[George Stolz]

No, this situation/OP is not acceptable.

250.24 [A] [5] read FPN also.

...

It cannot originate at a sub panel busbar and hitch a ride back on a load side feeder neutral.

Who said anything about connecting it to the neutral bar in the subpanel?

It cannot originate at a sub panel busbar and hitch a ride back on a load side feeder neutral.

I was not suggesting that the GEC "hitch a ride" on any of the feeder conductors.

I believe that according to 250.64(C)(3), the grounding bar in the sub-panel could be used as the permitted busbar.

And you certainly cant jumper from the EG busbar either.

Code reference please?

It has to originate at the service GC.

It does.

Service neutral connection, GEC to grounding bar in subpanel, bonding jumper from grounding bar to electrode(s). That is the 'one-line' I am picturing.

It is entirely independent of the feeder, a seperate GEC is run.

 

[Gmack]

Who said anything about connecting it to the neutral bar in the subpanel?

I was not suggesting that the GEC "hitch a ride" on any of the feeder conductors.

I believe that according to 250.64(C)(3), the grounding bar in the sub-panel could be used as the permitted busbar.


Code reference please?


It does.

Service neutral connection, GEC to grounding bar in subpanel, bonding jumper from grounding bar to electrode(s). That is the 'one-line' I am picturing.

It is entirely independent of the feeder, a seperate GEC is run.

George the OP IMO wanted to know if he could "jumper" a sub panel neutral or ground busbar to a/an electrode in leiu of the service GC/MAIN thereby creating a GEC.

I gave you a code reference.

Again IMO, your not seeing the "circuit".

Your seeing "words".

Your senario of running a "non" continuous GEC to a sub panel "busbar" rather than directly to the electrode makes no sense.

If you were to read and understand the code ref that I provided, you woundnt be arguing about it. Check the FPN.

If you had enough experience you woudnt even attempt what you suggested.

Its a bad idea for several means and would create paralelle paths.

You have a big problem George, understanding, paralelle paths and the code.

Right now you are dangerous in your "thinking" and application of the NEC.

BTW, it is not a design manual for the "untrained".

I suggest you consider .

 

[JohnE]

Gmack,

I agree with you on this one. However, while I don't think George was following th OP clearly, what he described would be legal, too. Essentially running GEC to subpanel then out to electrode. I can't imagine a reason to do this, but it would be code compliant.

 

[resistance]

I can't see a reason why it wouldn't be code complaint looking at Art. 250.64(c)(3). I just wanted some input, and it seems I got it!

 

[George Stolz]

First, I should preface this post by saying, I would not have the guts to try to attempt what I have said is permissible. The idea is kind of out there. But I think it is legal. I am not prepared to devote days of arguing with an AHJ to get it passed, though. Like John said, I can't imagine a scenario where it would even be useful.

I think John is right, after looking over the thread, I don't believe Resistance followed me to the conclusion that a independent GEC would need to be pulled directly to the subpanel busbar from the service. I believe, looking again, that he was proposing using the EGC of the feeder to "hitch a ride" for the bonding jumper running to the electrode(s).

I don't believe that would be legal.

However, I'm under the impression that Gmack believes a GEC must be run continuously, which is not entirely correct.