Cable Size

AWG is an acronym for "American Wire Gauge".

Where are you finding data for "British Standard" AWG?

I guessed there was a "missing" comma after BS/IEC. It just shows that punctuation is not irrelevant! It's a good thing engineers are not lawyers, or one would spend days arguing what a specification meant.

"It's a good thing engineers are not lawyers, or one would spend days arguing what a specification meant"

You're new here, aren't you. We spend days arguing about much less important things than that!

You're so right! You must mean like "What is this device" thread.

Is there an archaeologist's web site it could be tried on?

1. BS standard cable sizes go 0.5,0.75, 1.0, 1.25, 1.5, 2.5 sq.mm - logical since cross-sectional area is major factor for cables.
2. AWG is based on solid round wire section, like old BS. It does not appear to have a logical pattern - maybe it is based similarly to shotgun gauges, which are I believe based on the number of spherical balls, fitting the bore, which you can get out of a pound of lead.
3. When you look at several makers versions of multi-strand flexible "16 AWG" wire, there is a surprising variation in square millimetres copper area, with different strandings etc.( a variation of 1.2 to 1.3 sq. mm comes to mind)
   
4. At least with BS/IEC you know well how much copper you get for your money!
5. The twist in a stranded cable does affect the resistance, because each conductor is not straight, but a spiral (except one in middle!).
   

Whether it is AWG or BS what is important is the effective cross section. Diameter can vary for different constructions like,solid,stranded or flexible.Skin effect too should be taken into consideration.

Thanks For all the Anwswers

Regards

Jose

It is believed that the gauge number of a wire corresponded with the number of time the wire had been drawn to make it smaller.

For example after drawing the blank once you would have 1 gauge wire, draw it a second time gives 2 gauge and so on.

Of course the reduction in diameter and cross sectional area of each drawing process varies with material and numerous other factors so that's probably why there are so many different wire gauge standards in use throughout the world.

Personally I like to see things measured directly either a diameter or cross sectional area, as it makes things fare less likely to be misinterpreted.

Even for same cross sectional area current rating will depend upon type of conductor-solid,sector,circular or tubular

Hurrah for British Standard 7671, then.