calculating current carrying conductors

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journeyman0217

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when running 2 travel wires for a 3way switch, would both conductors be considered current carrying even though only one leg would actually carry current when the light fixture is on, for the purpose of calculating the number of current carrying conductors in a raceway?
 
journeyman0217 said:
when running 2 travel wires for a 3way switch, would both conductors be considered current carrying even though only one leg would actually carry current when the light fixture is on, for the purpose of calculating the number of current carrying conductors in a raceway?
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The CCC calculation excludes double counting of wires that, by design, cannot both be carrying current at the same time.
This lets you count two travelers as one CCC for adjustment purposes.
 
GoldDigger said:
The CCC calculation excludes double counting of wires that, by design, cannot both be carrying current at the same time.
This lets you count two travelers as one CCC for adjustment purposes.
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great thanks golddigger. i am in 310.15 and cant seem to reference that, do you know what article that is in?
 
journeyman0217 said:
great thanks golddigger. i am in 310.15 and cant seem to reference that, do you know what article that is in?
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Carefully read the title of Table 310.15(B)(3)(A) in the 2014 edition.

This is a change from 2011. In 2011, it said "current carrying conductors". In 2014, it was changed to "conductors" with a footnote that specifies the details. I'm paraphrasing from memory.
1. Spare conductors intended to carry current in the future shall be counted.
2. Only simultaneously energized conductors shall be counted at any time. This was specifically written to exclude counting traveller wires when the switching state only turns on 2 out of 3 of them, at any instant.
3. Equipment ground conductors shall not be counted
4. Whether or not to count the neutral, depends on circumstances and application of that neutral conductor. See 310.15(B)(4).
 
Carultch said:
Carefully read the title of Table 310.15(B)(3)(A) in the 2014 edition.

This is a change from 2011. In 2011, it said "current carrying conductors". In 2014, it was changed to "conductors" with a footnote that specifies the details. I'm paraphrasing from memory.
1. Spare conductors intended to carry current in the future shall be counted.
2. Conductors that cannot be simultaneously carrying current by design, shall only be counted
3. Equipment ground conductors shall not be counted
4. Whether or not to count the neutral, depends on circumstances and application of that neutral conductor. See 310.15(B)(4).
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ah, the damn footnote! it says "the count shall not include conductors that are connected to electrical components but that cannot be simultaneously energized" bingo
 
journeyman0217 said:
ah, the damn footnote! it says "the count shall not include conductors that are connected to electrical components but that cannot be simultaneously energized" bingo
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Which could be interpreted to mean that you do not even count the set once. Maybe the language will be tweaked eventually?
 
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