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hhsting

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Attached sketch shows one electric utility feeding trough that has two service discos. The sketch shows conductor #1 from neutral bar of one disco to neutral bar of another disco. Service disco #2 has each individual grounding electrodes.

Sketch as I am told complies with NEC 2014 section 250.64(D)(1). Neutral of service disco #2 is being used as ground bus bar.

Please Correct me if I am wrong or right but I don’t think attached sketch complies with NEC 2014 Section 250.64(D)(1) service disco #1 has no GEC tap and can you even it’s neutral bar as busbar mention 250.64(D)(1)?

please please help me out your opinion if sketch comply per NEC 2014 section 250.64(D)(1).
 

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augie47

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My understanding is that as shown it will not meet Code.
The attached is compliant method from one of Mike's videos.
1603221250196.jpeg
 

wwhitney

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So, to play devil's advocate for a second, what's the problem?

To get from the last picture (compliant) to the picture in the OP (under question), you have to make three changes:

(a) you eliminate the right splice point, making the last GEC tap just an extension of the common GEC.
(b) you move the left splice point into the right hand enclosure, instead of having it outside.
(c) finally, you change the splice method from a separate connector to using the neutral bar in the second enclosure.

Which of those changes is prohibited?

Cheers, Wayne
 

augie47

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My understanding is when you have multiple disconnects any connection needs to be made outside of any other disconnect, That comes from 250.64(D)
 

wwhitney

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I just reread (2017) 250.64(D)(1) and I don't see any language about the connection(s) being made outside of the enclosures.

Cheers, Wayne
 

augie47

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I think it comes from here:
A grounding electrode conductor tap shall extend to the inside of each disconnecting means enclosure.
 

wwhitney

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Berkeley, CA
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Retired
I think it comes from here:
A grounding electrode conductor tap shall extend to the inside of each disconnecting means enclosure.
Yeah, I saw that, but it doesn't say it has to originate from outside the disconnecting means enclosure. It just says it has to go inside the enclosure (which seems pretty obvious).

Cheers, Wayne
 

augie47

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I wish it were plainer, Perhaps someone knows a better reference. I am basing my opinion on videos and the handbook.
 

hhsting

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Location
Glen bunie, md, us
Occupation
Junior plan reviewer
Also see attached blue commentary done so that difficulty found in looping one enclosure to another part but that just blue commentary
 

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