cable distance

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don_resqcapt19

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There is nothing in the NEC, but there are enforceable voltage drop rules in the energy codes that have been adopted in some areas. A 12 amp load on #14 at 50' is approaching a 3% drop, but I am not sure what the actual requirements are in the energy codes.
 

MasterTheNEC

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There is nothing in the NEC, but there are enforceable voltage drop rules in the energy codes that have been adopted in some areas. A 12 amp load on #14 at 50' is approaching a 3% drop, but I am not sure what the actual requirements are in the energy codes.
Actually I don't think it is in the energy code (that's a proposal to come), it is actually in the IgCC Code (where adopted) and Title 24 out in California.
 

Smart $

Esteemed Member
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The only reference to 14 & 12 AWG along with max lenght in code I know of off hand is NEC 2014 210.12 (A) (3) b
Just to let others know without having to look that up it's pertaining dwelling unit AFCI 15 and 20A circuits to required locations
(3) A listed supplemental arc protection circuit breaker installed
at the origin of the branch circuit in combination
with a listed outlet branch-circuit type arc-fault circuit
interrupter installed at the first outlet box on the branch
circuit where all of the following conditions are met:

a. The branch-circuit wiring shall be continuous from
the branch-circuit overcurrent device to the outlet
branch-circuit arc-fault circuit interrupter.

b. The maximum length of the branch-circuit wiring
from the branch-circuit overcurrent device to the
first outlet shall not exceed 15.2 m (50 ft) for a
14 AWG conductor or 21.3 m (70 ft) for a 12 AWG
conductor.

c. The first outlet box in the branch circuit shall be
marked to indicate that it is the first outlet of the
circuit.​
 

mwm1752

Senior Member
Location
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And as mentioned in another thread the UL standard for supplemental arc protection breaker does not even exist yet. :)

so to those out there supplemental does not mean additional? I was understanding that a UL listed AFCI be it branch circuit rated or combination rated would be the supplement to the AFCI receptacle mentioned. Would it not mean the same as "supplemental electrode" is used in Art. 250 as a manner of additional?
 

GoldDigger

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so to those out there supplemental does not mean additional? I was understanding that a UL listed AFCI be it branch circuit rated or combination rated would be the supplement to the AFCI receptacle mentioned. Would it not mean the same as "supplemental electrode" is used in Art. 250 as a manner of additional?
Nope. It is a new device type which does not qualify as a branch/feeder AFCI, but apparently has some reason to exist.
 

mwm1752

Senior Member
Location
Aspen, Colo
Would it make a difference it the statement was -- a supplemental listed arc protection circuit breaker?
 
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GoldDigger

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It is mentioned in the code indirectly in that all of the other special wordings are referenced in a note to external standards. Supplemental is not, but in another thread one of our members quotes a UL rep as saying that the listing category is under development at this time.
 

mwm1752

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Location
Aspen, Colo
It is mentioned in the code indirectly in that all of the other special wordings are referenced in a note to external standards. Supplemental is not, but in another thread one of our members quotes a UL rep as saying that the listing category is under development at this time.

Well I sure hope it make projects cost effective---------:slaphead:
 

GoldDigger

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As I recall there was already a standard for branch/feeder AFCI breakers at the time they were added to NEC, there just were not any on the market yet.
This takes that forward view in the NEC to a higher level.
Apparently, for some reason, the CMP was not willing to wait another code cycle.
One would hope that the eventual devices will either be less expensive or less prone to nuisance trips, or both.
 

dereckbc

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Plano, TX
This is a design issue. Having said that 3% at 80% of breaker size will get you to about 60 feet 1-way distance on 12 AWG with 20 amp breaker.
 
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