Why are the conductors in 6/2 and 8/2 NM-B black and white?

Little Bill said:
I never understood the size limitation on re-identifying a conductor. What is the difference in marking a #4 vs a #6? Will the #6 melt if re-marked?
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My guess is it again is to protect the non qualified to some extent. Those people will work with 6 AWG and smaller quite often, though there are some won't touch anything that is "220". Give them an application that requires a larger conductor and they suddenly think it is more dangerous and will be more likely to get someone qualified to help with that circuit.

They will mess up three way/four way switching circuits on a 15 amp circuit but won't touch the range or dryer circuit even though it really is a simpler concept to wire those up.
 
Eddie702 said:
I think "someone" decided that remarking the smaller stuff isn't as necessary because you can easily buy all the colors. The larger stuff you can just by black and remark it.
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Not so much the case anymore though. Other than cable assemblies. Although most those can be custom ordered but not worth it unless you have a need to order a big lot of it.
 
The other day I opened up a junction box and all the wires were green, except somebody phase taped one white.
Clearly the other two greens were hots and the green with the white phase tape was the neutral.
I appreciated the white phase tape.

Then I traced the conduit back and found this:
1748386375119.png
 
tortuga said:
The other day I opened up a junction box and all the wires were green, except somebody phase taped one white.
Clearly the other two greens were hots and the green with the white phase tape was the neutral.
I appreciated the white phase tape.

Then I traced the conduit back and found this:
View attachment 2577879
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The box is old enough, but green wire was almost unheard of in this area. Not until Thhn/thwn started showing up. Was it thw?
 
kwired said:
Not so much the case anymore though. Other than cable assemblies. Although most those can be custom ordered but not worth it unless you have a need to order a big lot of it.
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Nothing in the Code stops someone from custom ordering a specific color if they don't to re-label a black conductor. Or, they can re-label a conductor that is stocked everywhere.
 
infinity said:
If we really want to dumb it down for the trunk slammers and YouTube generation they should just ban the re-identification of the white conductor in a cable just like in a raceway. If you need two ungrounded conductors just require a 3-wire cable.
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And require more expensive 3-wire cable when only 2 conductors are needed?
 
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