Sizing circuit, how close is too close

Status
Not open for further replies.

Twoskinsoneman

Senior Member
Location
West Virginia, USA NEC: 2020
Occupation
Facility Senior Electrician
I have a known load this circuit is going carrying. It is resistive mostly.
It is four small heaters and four small fans.
The heaters draw 3.48a
The fans draw 0.08a
According to these specs from the manufacture the total draw in the circuit will be 14.24a

How close do you typically get before up-sizing it to a 20a circuit or splitting it into two circuits?
 
Try 424.3 (B) "Fixed electric space heating shall be considered continuous load"
and 210.19 (A) (1)
Continuous load can only be loaded to 80%.
 
Last edited:
dezwitinc said:
Try 424.3 (B) "Fixed electric space heating shall be considered continuous load"
and 210.19 (A) (1)
Continuous load can only be loaded to 80%.


So forgive me for assuming, but i think he was originally going to run #14 wire. which has a rated ampacity of 25 amps (thhn) 80% of that would be 20 amps. So tell me , did i do this right? and since the code requires #14 to be on a breaker no bigger than 15 amps, he has to use a 20 amp breaker and therefore must have #12.

practicing my calcs. ;)
 
the 80% of circuit refers to the breaker sizing.14.24 amps is larger than the 12 amp(80%) continuous load on a 15 amp breaker.20 amp breaker has a 16 amp(80%) continuous load rating.the wire size for the most part is sized to the 100% rating of the breaker.your Analogy is off but still seems to get him to the proper wire size on a breaker.
 
Status
Not open for further replies.
Top