History of identification of nuetral conductor

Status
Not open for further replies.
M

mark nelson

Member
Location
New Mexico
I have been having trouble explaining why the neutral conductor is required to be continuous white for #6 and smaller, yet conductors #4 and larger can be field marked. Can anyone assist me on when the code (200.6) came about, as well as, why that particular size was determined. I have researched back as far as the 1991 code and it was the same as it is today.
 
mark nelson said:
I have been having trouble explaining why the neutral conductor is required to be continuous white for #6 and smaller, yet conductors #4 and larger can be field marked. Can anyone assist me on when the code (200.6) came about, as well as, why that particular size was determined. I have researched back as far as the 1991 code and it was the same as it is today.
Click to expand...
My guess is that manufacturers make white up to #6, and larger only by special order. The code has to work with what's available, which is why there are exceptions permitting cabled whites to be re-identified.
 
mark nelson said:
I have researched back as far as the 1991 code and it was the same as it is today.
Click to expand...

Yeah Mark, I have an 87' NEC, pretty much the same thing section 200.6

Larry that makes sense as far as the intent. I get this asked all the time and all I can say is "The NFPA had to draw a line somewhere....I guess"
 
It appears to me if first shows up in 1956:

"2005.b. Insulated conductors larger than No. 6, and weatherproof conductors of all sizes if used indoors, shall have an outer identification as specified in paragraph d of section 93101, or shall be identified by distintive marking at terminals during process of installation."

Back then, the term 'grounded' was not used. Instead, it was the 'identified' conductor.

In 1959, it was changed:

"200-6(b): Insulated conductors larger than No. 6 shall have an outer identification of white or natural gray, or shall be identified by distinctive white marking at terminals during process of installation."
 
Last edited:
480sparky said:
.

In 1959, it was changed:

"200-6(b): Insulated conductors larger than No. 6 shall have an outer identification of white or natural gray, or shall be identified by distinctive white marking at terminals during process of installation."
Click to expand...

That is great info. Thanks!:smile: I can only go back to 87' the first NEC I ever had and still on my shelf.
 
480sparky said:
It appears to me if first shows up in 1956:

Back then, the term 'grounded' was not used. Instead, it was the 'identified' conductor.

In 1959, it was changed:
Click to expand...
I was manufactured in 1955, but I still remember the term 'identified conductor.'

It's the wider blade, the ribbed conductor, the wire with threads in the strands, etc.
 
LarryFine said:
I was manufactured in 1955, but I still remember the term 'identified conductor.'

It's the wider blade, the ribbed conductor, the wire with threads in the strands, etc.
Click to expand...

For me it was '64 but I also was taught the same thing. :smile:
 
Status
Not open for further replies.
Top