# Art.  517  Wiring



## north star (Oct 22, 2009)

*'*

*I have an optometrist office with exam rooms in it. The electrical*

*contractor installed emt conduit in the each of the exam rooms [ as*

*per Article 517 in the 2008 NEC ].*



*My questions are: [ 1 ] How do I verify that the correct conductors*

*were installed, [ 2 ] Can I check the exam room circuits to verify*

*that they are actually "redundantly grounded", with some type of*

*GFCI circuit tester perhaps, [ 3 ] Should these "redundantly grounded"*

*circuits have a GFCI rated breaker in the interior elec. panel? I want*

*to continue learn as much as I can about these type installations.*



*Thanks ! * 



*`*


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## chris kennedy (Oct 24, 2009)

Re: Art.  517  Wiring

If you know EMT was used, did you see this at rough inspection? If so at that time you would have also seen the insulated EGC. If I an reading your post incorrectly, have the EC pull the devices out of the wall and check for the EGC. No GFCI protection is required unless there is a sink. (210.8(B)(5))


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## EPrice (Oct 26, 2009)

Re: Art.  517  Wiring

I agree with what Chris has said.  The applicable sections are 517.13 (A) and (B).  Those sections require a wiring method with a conduit or armor that qualifies as an equipment ground plus an insulated equipment grounding conductor.  The EMT would meet the first requirement, and if the contractor pulled an insulated equipment grounding conductor, that would meet the second requirement.  The NEC doesn't use the term "redundantly grounded" that I know of.


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## chris kennedy (Oct 26, 2009)

Re: Art.  517  Wiring



			
				EPrice said:
			
		

> The NEC doesn't use the term "redundantly grounded" that I know of.


I believe this to be correct, although I use this term when explaining 517.13 as I am a NECHB user and it appears twice in the commentary.

Part of the commentary following 517.13(A);



> The branch circuit wiring method used in these areas is one component of a two-part redundant grounding scheme unique to patient care areas.


And part of the commentary following 517.13(B);



> The requirements in 517.13(B) cover the second component of the redundant grounding approach.


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