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Discussion Starter · #1 · (Edited)
Due Dilligence: OK, I've checked Article 100, Googled it and checked here on Electrician Talk as well, and it's still not absolutely clear to me (and apparently others) whether the neutral is considered Current Carrying. Some key points I've found are:
  • It does carry current, but is not current carrying conductor (or something like that),
  • and, Yes it is a Current Carrying Conductor, but doesn't always carry current,
  • there are many references to NEC 310.15(B)(4)...which doesn't exist anymore...Whatever.
I'm neck deep in studying Table 310.16 (through Jade Learning, which is excellent), and the values for allowable ampacity need to be modified for conditions such as ambient temperature, number of conductors in a raceway or cable, or other conditions of use. And, as many others say..."it's clear as mud" whether NEC considers the neutral to be a Current Carrying Conductor.

What say you all?

Edit: I just found it in the 2020 NEC Handbook. Section 310.15(E) reminds us that neutral conductors in some cases, is NOT considered current carrying. From where I'm standing, it looks like in all cases but one, is the neutral considered current carrying.

310.15(E) Neutral Conductor. Neutral conductors shall be considered current carrying in accordance with any of the following:
  1. A neutral conductor that carries only the unbalanced current from other conductors of the same circuit shall not be required to be counted when applying the provisions of 310.15(C)(1).
  2. In a 3-wire circuit consisting of tho phase conductors and the neutral conductor of a 4-wire, 3-phase, wye-connected system, a common conductor carries approximately the same current as the line-to-neutral load currents of the other conductors and shall be counted when applying the provisions of 310.15(C)(1).
  3. On a 4-wire, 3-phase wye circuit where the major portion of load consists of nonlinear loads, harmonic currents are present in the neutral conductor; the neutral conductor shall therefore be considered a current-carrying conductor.
Additional Commentary text: Nonlinear loads on 3-phase circuits can cause an increase in neutral conductor current.
 

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Discussion Starter · #3 ·
It’s a current carrying. Conductor end of story. There’s no way to ever rule out a load unbalance.
So, just to be crystal clear, when dealing with Table 310.16 to determine conductors & ampacities, that the neutral is counted as a current carrying conductor. That it's one of the three, or when counted it adds up to more than three. Period. End of story. Pack up sh!t and go home. Correct?
 

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Almost everything has electronics in it so the neutral is considered current carrying. Years ago it was considered only to carry the unbalanced load of a 240/120 volt single phase system that was feeding resistive loads only. Over the past 30 years or so RLC circuits came into play so now we have all sorts of mystical stuff to deal with. We have no control of what is plugged into the receptacle or what light fixtures the customers use.
 

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It is also called the grounded conductor
I am starting to use the simple terms like white wire, green wire, or bare wire. Some people get confused with grounded, grounding, bonding, so it makes things simpler to explain things. For instance, do we ground the pool or do we bond the pool? Do we run a grounding conductor or a grounded conductor?
 

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Discussion Starter · #7 ·
I am starting to use the simple terms like white wire, green wire, or bare wire. Some people get confused with grounded, grounding, bonding, so it makes things simpler to explain things. For instance, do we ground the pool or do we bond the pool? Do we run a grounding conductor or a grounded conductor?
This can't be emphasized enough. Not only is "grounding" and "grounded" terminologies confusing but their purpose is confusing due to the vernacular. Journeymen I still work with continue to say that electricity "wants to go to ground" and think the grounding electrode is part of the ground fault path.

It was here that someone clarified it to me, regarding "grounded" vs "grounding". "Ed is old, and has white hair." which means, groundED is white, which is neutral. GroundING is green, which is the EGC.
 

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This can't be emphasized enough. Not only is "grounding" and "grounded" terminologies confusing but their purpose is confusing due to the vernacular. Journeymen I still work with continue to say that electricity "wants to go to ground" and think the grounding electrode is part of the ground fault path.

It was here that someone clarified it to me, regarding "grounded" vs "grounding". "Ed is old, and has white hair." which means, groundED is white, which is neutral. GroundING is green, which is the EGC.
As I get older I find that I know what things are but hard to explain in modern terms. Throw in some acronyms and emojis and then I am really lost.
 

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I can't speak for NEC, but my whole apprenticeship (school, work, and code) a neutral was not counted as current-carrrying in a conduit when a full set of hot/phase conductors accompanied it. The CEC is largely based on the intent of the NEC.

Engineering specs may supercede that. Some jobs (office, data center, etc) spec'd for one size larger neutral, or 200% neutral. Others want dedicated neutrals for everything (until they realize the cost!)
 

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the thing tripping you up is whether to COUNT it in one or more situations requiring a calculation
counting it or not in a calculation has nothing to do with its function and reason to be in the circuit

the reason to count it or not has to do with the calculation

as stated: it is always a current carrying conductor in every case
otherwise it would not need to be included in the circuit

southwire has already begun to sell 12-2G romex with a #10AWG neutral
they also already sell 12-2G romex with the purple and gray dimmer wires included in the overall jacket

i like the thing with Ed having white hair :)

a groundED conductor (neutral, white) is intended to carry current in normal circumstances
a groundING conductor (bare or green) is intended to Only carry current in Abnormal circumstances

if you truly want to get a grip on the NEC you need to get comfortable with those terms because that is what they use every time

my journeyman used to say "boy that ground will F you up" but he was actually talking about a neutral, in particular a lost neutral in a circuit
i suspect the reason the old timers call it "ground" is the result of old romex only having a black and white and ground is less syllables than neutral
 

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in the 2017 NEC ... 310.15 (B) (4) talks about a conductor that is covered or bare and that its ampacity should be equal to the lowest ampacity rating of the insulated conductors
in this case covered does not mean insulated
for instance the outer covering of romex is not considered insulation for the purposes of the nec, whether it provides some insulation or not is irrelevant

in the 2020 NEC it is 310.15 (D)

the purpose of this whole portion of the article, is so that you can not put a bare 20AWG in the conduit for a EGC unless the insulation of all of the conductors is rated for the temp this would cause during a fault

in other words the Ampacity of all of your wires to has meet the lowest insulation temp that you are using

in other words use all the same insulation and all 12 AWG in a 20amp circuit, no downsizing of the ground or any other wire
im not sure you can mix insulations but it is a bad idea and not good practice either way
__ * * * * * * * * * * * * * * *
since you are working on ampacity of conductors
the whole point of the article is to make sure you dont cause a temperature rise in the conduit that would exceed the insulation rating
this temperature rise would not be from induction
but plain amps which also cause heating.
the conductors need room to breath and give off the heat
otherwise it could build up to a dangerous level and damage the insulation of the conductors
you know what that means,,,, a big flash/bang and then a fire
 

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I can't speak for NEC, but my whole apprenticeship (school, work, and code) a neutral was not counted as current-carrrying in a conduit when a full set of hot/phase conductors accompanied it. The CEC is largely based on the intent of the NEC.
I think both NEC and CEC align on this.

A "Neutral" is not counted as a CCC, but the "identified" conductor is (The grounded conductor in the NEC)
 

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I think both NEC and CEC align on this.

A "Neutral" is not counted as a CCC, but the "identified" conductor is (The grounded conductor in the NEC)
i dont think we use an "identified conductor"
we do use a neutral and it is sometimes counted as a CCC in a calculation
as the op pointed out ,, we do have at least one case where the neu is not required to be counted in a calculation

for normal usage and Not a calculation i think the neutral is always defined as a CCC
therefor the term grounded conductor as opposed to an Ungrounded conductor, which is how nec says a hot
 

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In many cases the neutral isn't a current carrying conductor. Here is a good list for you

Here's some examples of when to count and not count the neutral as a current carrying conductor or CCC:
A) 2 wire circuit w/ 1 ungrounded, 1 neutral = 2 CCC's
B) 3 wire circuit w/ 2 ungrounded, 1 neutral = 3 CCC's
C) 4 wire circuit w/ 3 ungrounded, 1 neutral = 3 CCC's*
Notes:
A) A normal 2 wire circuit has equal current flowing in each of the circuit conductors so they both count as CCC's.
B) In this circuit the neutral current will be nearly equal to the current in the ungrounded conductors so the neutral counts as a CCC
C) In this circuit the neutral will only carry the imbalance of the current between the three ungrounded conductors so it is not counted as a CCC, with an exception,
*if the current is more than 50% nonlinear (see below for NEC article 100 definition) then the neutral would count as a CCC.

1Ø- 120/240 volt system-different circuit types:
D) 2 wire circuit w/ 1 ungrounded, 1 neutral = 2 CCC's
E) 3 wire circuit w/ 2 ungrounded, 1 neutral = 2 CCC's
Notes:
D) A normal 2 wire circuit has equal current flowing in each of the circuit conductors so they both count as CCC's.
E) In this circuit the neutral will only carry the imbalance between the two ungrounded conductors so the neutral is not counted as a CCC.
Nonlinear Load. A load where the wave shape of the steady-state current does not follow the wave shape of the applied voltage.
Informational Note: Electronic equipment, electronic/electric-discharge lighting, adjustable-speed drive systems, and similar equipment may be nonlinear loads.
 

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Discussion Starter · #15 ·
the thing tripping you up is whether to COUNT it in one or more situations requiring a calculation
counting it or not in a calculation has nothing to do with its function and reason to be in the circuit

the reason to count it or not has to do with the calculation

as stated: it is always a current carrying conductor in every case
otherwise it would not need to be included in the circuit

southwire has already begun to sell 12-2G romex with a #10AWG neutral
they also already sell 12-2G romex with the purple and gray dimmer wires included in the overall jacket

i like the thing with Ed having white hair :)

a groundED conductor (neutral, white) is intended to carry current in normal circumstances
a groundING conductor (bare or green) is intended to Only carry current in Abnormal circumstances

if you truly want to get a grip on the NEC you need to get comfortable with those terms because that is what they use every time

my journeyman used to say "boy that ground will F you up" but he was actually talking about a neutral, in particular a lost neutral in a circuit
i suspect the reason the old timers call it "ground" is the result of old romex only having a black and white and ground is less syllables than neutral
I'm speaking specifically about counting towards the calculation using 310.15(C)(1). We derate based on number of Current Carrying Conductors. I am not talking about the "function and reason to be in the circuit," as you mentioned.

You emphasized that the neutral is a Current Carrying Conductor "always" and "in every case," yet, as I mentioned in my post, Section 310.15(E)(1) clearly states that a neutral conductor shall not be required to be counted when applying the provisions of 310.15(C)(1). It looks like there's at least one scenario where the neutral isn't required to be counted as a CCC.
 

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Discussion Starter · #16 · (Edited)
In many cases the neutral isn't a current carrying conductor. Here is a good list for you
Mind me asking where you got this list from and what NEC it's based on?

Edit: NM, I found you posted the same in 2013. And, it just so happens to correspond to my 2020 Handbook 310.15(E)(1)-(3).
They seem to match up with what NEC states. However, both NEC 2020 and your note both support only one situation where the neutral isn't counted as a current carrying conductor.
 

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In many cases the neutral isn't a current carrying conductor. Here is a good list for you
like the op you are mixing and matching terms, situations, and definitions
and that was the root of his frustration in the op (at least that is how i read it)
as well as some misunderstanding in some of the replies

i think the question is the difference between
whether you count the neutral in a calculation
compared to how it is defined

by definition it carries current in normal situations, in a MWBC there will always be some tiny imbalance or it would not need to be included in the circuit to start with
whether you have to count it in a calculation depends on the scenario
 

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Discussion Starter · #18 ·
like the op you are mixing and matching terms, situations, and definitions
and that was the root of his frustration in the op (at least that is how i read it)
as well as some misunderstanding in some of the replies

i think the question is the difference between
whether you count the neutral in a calculation
compared to how it is defined

by definition it carries current in normal situations, in a MWBC there will always be some tiny imbalance or it would not need to be included in the circuit to start with
whether you have to count it in a calculation depends on the scenario
Again, I am exclusively referring to counting the neutral regarding the calculation. No confusion on that part and practical application. Everything I read, specifically NEC 310.15(E)(1) shows only one case where the neutral is not counted as a CCC with respect to the calculation.
 

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Mind me asking where you got this list from and what NEC it's based on?

Edit: NM, I found you posted the same in 2013. And, it just so happens to correspond to my 2020 Handbook 310.15(E)(1)-(3).
They seem to match up with what NEC states. However, both NEC 2020 and your note both support only one situation where the neutral isn't counted as a current carrying conductor.
counting in a calculation is not the same as talking about a neutral's function and definition
perhaps it is me who does not understand your question?

so based on what dennis gave you, is your question answered ?
 

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Discussion Starter · #20 ·
counting in a calculation is not the same as talking about a neutral's function and definition
perhaps it is me who does not understand your question?

so based on what dennis gave you, is your question answered ?
I believe it is answered. Your list coincides with 2020 NEC, which only one case shows the neutral as not being counted as CCC with respect to Table 310.15(C)(1). Thanks.
 
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