# Standard wire rating vs continuous load rating



## 480sparky (Sep 20, 2007)

80% and 125% are mentioned several times in the NEC.


----------



## HARRY304E (Sep 15, 2010)

guitarboyled said:


> #14 wire is rated at 15 amps. Continuous loaded at 80% = 12 amps.
> 
> Is the 80% value an actual standard in the NEC or common practice?


Heres a link.http://www.nfpa.org/aboutthecodes/AboutTheCodes.asp?DocNum=70


----------



## etb (Sep 8, 2010)

480sparky said:


> 80% and 125% are mentioned several times in the NEC.


They're also reciprocals of one another.


----------



## raider1 (Jan 22, 2007)

guitarboyled said:


> #14 wire is rated at 15 amps.




Not necessarily, the ampacity of the #14 also depends on the temperature rating of the terminals that it is connected to. Also until the 2011 came out #14 has an ampacity of 20 amps at 60 degrees C.




> Continuous loaded at 80% = 12 amps.


 
The #14 conductor's ampacity does not change due to continuous or non-continuous loading. What changes is how we determine the calculated load for the circuit.





> Is the 80% value an actual standard in the NEC or common practice?


As already mentioned the 80% rule is the reciprocal of the 125% rule that is found in 210.19(A)(1) and 215.2(A)(1) as well as many other places in the NEC.

Chris


----------



## wayne g (Nov 28, 2010)

All over the NEC


----------

