2017 NEC second draft

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Smart $

Esteemed Member
Location
Ohio
I'm interested in seeing the language they use for saying that, but don't have a login. Is it still the language they had in 2014?
Not the same wording as 2014.
(B) Increased in Size. If ungrounded conductors are increased in size to account for voltage drop, wire-type equipment grounding conductors shall be increased in size. The increase in size shall be at least in the same proportion as the increase in the size of the ungrounded conductors using their circular mil area.
 

Carultch

Senior Member
Location
Massachusetts
Not the same wording as 2014.

Well, it is quite an improvement in my opinion, as it now gets straight to the point of the intent of the rule.

So now you no longer have to upsize EGC, if you've upsized the main conductors because you had left-over wire that is larger than necessary, kicking around from a previous job. Or if you've prepared for 60C terminations in your design worst-case-scenario, and end up with 75C terminations as is the industry norm. Or if you have equipment that specifically calls for larger than necessary wire.
 

Smart $

Esteemed Member
Location
Ohio
Well, it is quite an improvement in my opinion, as it now gets straight to the point of the intent of the rule.

So now you no longer have to upsize EGC, if you've upsized the main conductors because you had left-over wire that is larger than necessary, kicking around from a previous job. Or if you've prepared for 60C terminations in your design worst-case-scenario, and end up with 75C terminations as is the industry norm. Or if you have equipment that specifically calls for larger than necessary wire.
That's correct. No more "or if's". Only for voltage drop. It's back to the intent of the original version... with the exception that the original version only required upsizing where a wire-type EGC was required. That is, you originally didn't have to upsize if you used a metallic raceway wiring method.
 

wwhitney

Senior Member
Location
Berkeley, CA
Occupation
Retired
That is, you originally didn't have to upsize if you used a metallic raceway wiring method.
Are you saying that under the older wording, if you had both a wire-type EGC and a metallic raceway EGC, you didn't need to upsize the wire-type EGC?

Cheers, Wayne
 

peter d

Senior Member
Location
New England
I wanted the NEC to go all in. That's the best way to reveal these things for the fraud they are.

I agree, but just the expansion to kitchens and the issues I've observed with AFCI's tripping with certain appliances is enough, IMO. Still, you're right that it would have really upped that ante if AFCI's started tripping with furnaces and other equipment.
 

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Retired Electrical Contractor
That's correct. No more "or if's". Only for voltage drop. It's back to the intent of the original version... with the exception that the original version only required upsizing where a wire-type EGC was required. That is, you originally didn't have to upsize if you used a metallic raceway wiring method.


So if I have 10 awg conductor for de-rating purposes and install a 20 amp overcurrent protective device then I can use a #12 equipment grounding conductor?
 

Sierrasparky

Senior Member
Location
USA
Occupation
Electrician ,contractor
So if I have 10 awg conductor for de-rating purposes and install a 20 amp overcurrent protective device then I can use a #12 equipment grounding conductor?

Yes, but IIRC we're talking like back in the '70's.

Are you saying that under the older wording, if you had both a wire-type EGC and a metallic raceway EGC, you didn't need to upsize the wire-type EGC?

Cheers, Wayne

That's correct. No more "or if's". Only for voltage drop. It's back to the intent of the original version... with the exception that the original version only required upsizing where a wire-type EGC was required. That is, you originally didn't have to upsize if you used a metallic raceway wiring method.


Ok , so if you are using a cable size 8 NM and upsize to 6nm . It won't work as #8 and #6 use the same size #10 if I recall correctly.
 

Carultch

Senior Member
Location
Massachusetts
Ok , so if you are using a cable size 8 NM and upsize to 6nm . It won't work as #8 and #6 use the same size #10 if I recall correctly.

8 NM is built with 40A circuits in mind, while 6 NM is built with 50 or 60A circuits in mind. All of these use a #10 EGC by default, so a #6 NM with a #8 EGC simply isn't a readily available product.

A solution is that you can put in a 60A breaker (if allowed by your equipment), and then the #10 EGC is sufficient.
 

Smart $

Esteemed Member
Location
Ohio
Ok , so if you are using a cable size 8 NM and upsize to 6nm . It won't work as #8 and #6 use the same size #10 if I recall correctly.
Under the prospective wording, depends on the reason for the upsize... which you did not clarify. If the reason is not for voltage drop, yes it will work.
 

iwire

Moderator
Staff member
Location
Massachusetts
Under the prospective wording, depends on the reason for the upsize... which you did not clarify. If the reason is not for voltage drop, yes it will work.

It would work when his area adopts the 2017 NEC, until then no regardless of the claimed reason.
 

George Stolz

Moderator
Staff member
Location
Windsor, CO NEC: 2017
Occupation
Service Manager
So if I have 10 awg conductor for de-rating purposes and install a 20 amp overcurrent protective device then I can use a #12 equipment grounding conductor?

That is true under the 2014. Ampacity is not the number shown on Table 310.15(B)(16). The definition of ampacity is based upon the conditions of use. Therefore, a 10 AWG conductor on a 20A circuit in a raceway with 12 other conductors gets a 12 AWG EGC - the conductor was not upsized, it was sized correctly according to the conditions of its use.
 
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