120/208 wye 3phase 4 wire

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2xcheck

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Maintenance electrician
I seen alot of threads with just confusing me more . Running a new service for a salon. meter will be about 70 ft from new panel . Is the neutral conductor considered current carrying from what I gather it is not, but looking for some reassurance if I'm misunderstanding something. don't want a disaster at inspection because I didn't adjust for 4 or more ccc. Thanks
 
2xcheck said:
I seen alot of threads with just confusing me more . Running a new service for a salon. meter will be about 70 ft from new panel . Is the neutral conductor considered current carrying from what I gather it is not, but looking for some reassurance if I'm misunderstanding something. don't want a disaster at inspection because I didn't adjust for 4 or more ccc. Thanks
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you are correct, it is not.
 
2xcheck said:
I seen alot of threads with just confusing me more . Running a new service for a salon. meter will be about 70 ft from new panel . Is the neutral conductor considered current carrying from what I gather it is not, but looking for some reassurance if I'm misunderstanding something. don't want a disaster at inspection because I didn't adjust for 4 or more ccc. Thanks
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Most of the time, the neutral isn't considered a CCC for purposes of ampacity adjustments, no matter what the balancing among the phases. The theory behind this, is that assuming simple linear loads, the heat generated among the 4 conductors carrying current in a 3-phase wye system will not exceed what it would be, if the three phases carried equal amounts of current and the neutral carried zero current. When there is current on the neutral, there is less current on at least one of the phases.

That is, unless the neutral is a mandatory part of the return path, even when balanced. Such as when you pull two phases and a neutral off a 3-phase wye grid, to supply a collection of line-to-neutral single phase loads on both phases. Even when both phases carry equal current, the neutral has to also carry current to complete the circuit.

The exception is harmonic-intensive loads being present on the neutral conductor, and in particular, harmonics that are multiples of 180 Hz. These add up on the neutral, rather than cancel.
 
Thanks guys really appreciate it . I have another question pertaining to this job I've stated. i don't know if I'm reading this correctly or not but in 215.2 a1 exception 1 is this telling me I dont have to apply 125% to conductors if the equipment is rated for 100% load?
 
2xcheck said:
Thanks guys really appreciate it . I have another question pertaining to this job I've stated. i don't know if I'm reading this correctly or not but in 215.2 a1 exception 1 is this telling me I dont have to apply 125% to conductors if the equipment is rated for 100% load?
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Yes that is correct, but long story short it would be pretty rare that you would be using 100% rated equipment. There probably isn't even much continuous loads other than lighting in a salon.
 
electrofelon said:
Yes that is correct, but long story short it would be pretty rare that you would be using 100% rated equipment. There probably isn't even much continuous loads other than lighting in a salon.
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They want a 300 amp panel. Yea I was not sure if a meter socket are usually rated 100 % I thought I seen breakers over 250 are ? I got some much on my mind .lol.
 
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