AWG Wire Size Nomenclature

[Hillbilly-FL]

New to the forum and have an interesting question that I have yet been able to find the answer myself.
Is there somewhere in the NFPA/NEC that specifically states that the wire sizes of "0" and "1/0" are the same thing?
I know this is the industry standard and that they are the same but because of a typo in the contractual documents I need something form a governing document that states this.

Thanks,

Scott

 

[GoldDigger]

Not sure where you would find it, since the difference relates purely to notational convention rather than a size standard per se.
Originally the guage sizes above 1 were written as 0 (simple enough sequence) followed by 00, 000, and 0000. Analagous to E, EE and EEE in shoe widths and D, DD ... in bra cup sizes.
For readabilty the / convention came into use where the left number gives the number of zeroes in the wire guage.
0000 => 4/0
000 => 3/0
00 => 2/0, and for completeness
0 => 1/0

See https://www.amazon.com/ask/questions/Tx1RKK7ZX9TPCM0 for a non-authoritative comment.

Which brings to mind the story of two cowboys comparing their girl friends breast sizes.
First said "She is an 8-3/4"
Second "How are you measuring that?"
First "Stetson"

 

[winnie]

My _guess_ is that you need to go to the ASTM standard for AWG:

Standard Specification for Standard Nominal Diameters and Cross-Sectional Areas of AWG Sizes of Solid Round Wires Used as Electrical Conductors

This specification prescribes the standard nominal diameters and cross-sectional areas of American Wire Gage (AWG) sizes of solid round wires, used as electrical conductors, and gives equations and rules for the calculation of standard nominal mass and le

www.astm.org

Is there any place in code where the wire is referred to as '0' rather than '1/0'?

The 'Circular of the Bureau of Standards' uses 0, 00, 000, and 0000 in one place (figure on page 18) and 0, 2-0, 3-0, 4-0 elsewhere. Doesn't seem to use 1/0 anywhere.

-Jon

 

[LarryFine]

Is there somewhere in the NFPA/NEC that specifically states that the wire sizes of "0" and "1/0" are the same thing?
I know this is the industry standard and that they are the same but because of a typo in the contractual documents I need something form a governing document that states this.

Ask them how many zeros "one ought" could be.

 

[GoldDigger]

Ask them how many zeros "one ought" could be.

My London-born barber had the vanity plate "BBOR0BB"

Spoiler

Two-B OR naught two-B

 

[suemarkp]

Why is this an issue? If a contract says use size 0 wire, what size are they going to use? If you follow the gauge table, as it goes 3 to 2 to 1, it then goes 1/0, 2/0, ... Are they saying there is no size between 1 and 1/0? If you were unsure, wouldn't you use the next size up??? You may be able to look in the older versions of the NEC on the NFPA website (its free to look at them if you give them your email address). If you go back far enough, the wire tables may list 0, 00, 000 instead of 1/0, 2/0, 3/0... The current book seems pretty consistent and I think you will only find 1/0 whenever size 0 is used.

 

[infinity]

Why is this an issue? If a contract says use size 0 wire, what size are they going to use?

0 or 1/0 same thing. No need to complicate it. The NEC in T310.15(B)(16) and elsewhere uses 1/0.

 

[Hillbilly-FL]

Why is this an issue? If a contract says use size 0 wire, what size are they going to use? If you follow the gauge table, as it goes 3 to 2 to 1, it then goes 1/0, 2/0, ... Are they saying there is no size between 1 and 1/0? If you were unsure, wouldn't you use the next size up??? You may be able to look in the older versions of the NEC on the NFPA website (its free to look at them if you give them your email address). If you go back far enough, the wire tables may list 0, 00, 000 instead of 1/0, 2/0, 3/0... The current book seems pretty consistent and I think you will only find 1/0 whenever size 0 is used.

This has become a contractual issue because the DOT in my state has a error in their estimating system. The wire sizes are bundled into groups and assigned a Pay Item Number. For example, 700-1-12 is for furnish and install #8-#6. The issue is that the -14 group is #1-#0 and the -15 group is #1/0-#3/0 and there is currently a price difference of $1.43/LF between the groups. This is on a large interchange lighting project so the cost difference is significant. Everyone knows that these are the same but the contractor sees an opening to make a money grab by exploiting the error and I was hoping that there was something in the NEC that states this to shut them down on a claim since the NEC is one of our governing docs. I truly don't think this is going to get very far but it would have helped to nip it in the bud so to speak.

Thanks to all for the help!!

 

[wwhitney]

Seems like it should be easy to establish that #0 = #1/0. Then you are left with a contract that breaks things down into groups as:

-12 = #8-#6 (3 nominal sizes, 2 actual)
-13 = #4-#2 (3 nominal, 3 actual)
-14 = #1-#1/0 (2 nominal, 2 actual)
-15 = #1/0-#3/0 (3 nominal, 2 actual)

But there's an overlap, #1/0 shows up in two different groups. So there's a typo in -14 or -15.

You could fix it by keeping #1/0 in the -15 group, but then your pattern of group sizes (actual) is 2, 3, 1, 3. Or you could fix it by keeping #1/0 in the -14 group, giving a pattern of group sizes of 2, 3, 2, 2.

Obviously the latter is more even, and as a non-lawyer, I would hope that would be sufficient to demonstrate that the typo is in the -15 group, which should be #2/0 - #3/0.

Cheers, Wayne