GEC point of connection 690.47(C)(3)

[shortcircuit2]

690.47(C)(3) 2011 allows for the GEC to run with the AC circuit conductors to the grounding busbar in the associated equipment. When using micro inverters multiple strings go to a combiner panel. This seems to allow the GEC termination at an combiner panel...not all the way back to the main service panel where the main GEC is.

Any comments regarding this would be helpful.

Thanks, shortcircuit

 

[jaggedben]

I have never seen the GEC terminated anywhere but in the main panel where the premises GEC(s) are located. Just recently inspectors in our jurisdiction let us know that they would accept termination in a busbar instead of an irreversible crimp to a premises GEC. I have not tried terminating the GEC in a subpanel grounding busbar and seeing what an inspector would say. While I agree that the new code language seems to imply that this is an option, it would also seem that the whole point of 690.47(C3) requiring an 'unspliced or irreversibly spliced' GEC is to ensure that it not get disconnected at a subpanel or junction box while someone is might be working on the premises.

BTW, your question really pertains to any system(s) tied into a subpanel of any kind, not just microinverter systems or systems with combiner panels.

 

[shortcircuit2]

Ben, the wording does seem to allow termination at any busbar, even a j-box with a grounding busbar? I don't believe that was the intent, rewording the article is needed.

Thanx, shortcircuit

 

[Zee]

GEC stands for Grounding ELectrode Conductor. So...a conductor that runs to the grounding electrode.

If it doesn't run there, (or to the main bus with other GEC's) it ain't a GEC, is it?

 

[Zee]

You are right, The wording does possibly confuse.

(you may know, but gr. bushngs are needed when running the GEC in metallic conduit
and it must be continuous -- unspliced))

 

[jaggedben]

Ben, the wording does seem to allow termination at any busbar, even a j-box with a grounding busbar? I don't believe that was the intent, rewording the article is needed.

Thanx, shortcircuit

I don't think a j-box can be considered 'equipment', but otherwise I agree. The wording is vague and probably does not account well for the intent. I do not believe the CMP intended this to apply to subpanels.