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Discussion Starter · #1 ·
when derating wires due to conduit fill, there is exceptions talking about the neutral not needing to be counted as a "current carrying conductor" if it is carrying only the unbalanced load of a multiwire circut.... so when do you not have to count the neutral as a current carrying conductor?


thanks for all the help you can give me!
 

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I own stock in FotoMat!
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Derating and conduit fill are totally different items.

Derating is to reduce the amount of heat that can affect the insulation. Fill is how many little circles can be put in to a large circle.
 

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NJ-IEC
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when derating wires due to conduit fill, there is exceptions talking about the neutral not needing to be counted as a "current carrying conductor" if it is carrying only the unbalanced load of a multiwire circut.... so when do you not have to count the neutral as a current carrying conductor?


thanks for all the help you can give me!

Easy, when it's not a current carrying conductor. :blink:


You answered your own question. When the neutral is neutral, a common to two ungrounded conductors, it does not need to be counted as a CCC.
 

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Easy, when it's not a current carrying conductor. :blink:


You answered your own question. When the neutral is neutral, a common to two ungrounded conductors, it does not need to be counted as a CCC.

Errrr.... umm...... Not always. Take a trip down 310.15(B)(4)(b) and (c).
 

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Derating and conduit fill are totally different items.

Derating is to reduce the amount of heat that can affect the insulation. Fill is how many little circles can be put in to a large circle.
LoL, Do ya hasta bust everyone's balls 480?

.... so when do you not have to count the neutral as a current carrying conductor?

My opinion is that you always count a neutral as a current carrying conductor. If you believe that you have a valid exception then follow it. If you are not sure, don't.

310.15(B)(4) describes the only case I know where you are allowed to not count the neutral conductor as a current carrying conductor.

Personally, I would only use that if I had to. Do understand I prefer a little overkill anytime I can afford it.
 

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Discussion Starter · #6 ·
Errrr.... umm...... Not always. Take a trip down 310.15(B)(4)(b) and (c).





310.15 b4 a b c is why i asked the original question... ok i miss-worded the original question, im derating because the number of ccc in a pipe, not for "pipe fill" so does the neutral load depend on the load the circuts are serving? i just want to know if i need to derate for my neutrals... if not i can pack more crap in my pipes and gutters! i always play it safe and count it as a ccc but i want to know for sure now!
 

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NJ-IEC
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310.15 b4 a b c is why i asked the original question... ok i miss-worded the original question, im derating because the number of ccc in a pipe, not for "pipe fill" so does the neutral load depend on the load the circuts are serving? i just want to know if i need to derate for my neutrals... if not i can pack more crap in my pipes and gutters! i always play it safe and count it as a ccc but i want to know for sure now!
Which code cycle are you using?
 
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