Just looking at your posts here and often you mention wire gauge as 12/2 or 14/2 etc

Here in the UK we use cable like 2.5mm Twin&Earth (2.5T&E) or single cores 1.5mm.
Where the size stated is the diamiter of the copper core see here
How is cable sized where you are?

AWG or American Wire Gauge.

14 AWG is rated approx 20 amps

12 AWG is rated approx 25 amps

I've written a little on this, with some tables:
http://www.global-electron.com/wiresizes.htm

T&E looks very similar to NM cable.

Interesting- 2.5mm T&E cable is smaller than #12, yet allowed for 24A circuits, whereas the larger #12 NM is only approved to 20A?

I seem to remember hearing somewhere that metric amps are slightly smaller than non-metric, so that accounts for the difference in ampacity values.

kidding -
Radar

Actually 12 ga is good for 25a (310.16)
240.4(D) reduces that to 20a because the "small conductors" are most likely to serve receptacles where the installer has no control over what the user will plug in. They will keep plugging things in until the breaker trips, then unplug the clock. 240.4(D) forces the 80% rule on the user.
Perhaps Europeans are more dilligent about load management.

Not the diameter -- 1.0, 1.5, 2.5 etc. are the cross-sectional area of the conductor, in square millimeters.

The pre-metric cables (before 1970) use a size designation based on the strand diameter, e.g. 3/.036 is a conductor consisting of three strands, each of .036" diameter.

Here is a comparison of American 12/2 w/gnd Romex and British 2.5 sq. mm "T&E" cable:







Note that the ground conductor on the U.K. cable is a size smaller than the insulated conductors, 1.5 sq. mm on this 2.5 cable.

You'll note also that British T&E doesn't have any paper inside the outer sheath like Romex.


[This message has been edited by pauluk (edited 07-23-2006).]

OK, so it's more like UF! Is T&E rated for wet areas?

I'm going to have to pick up some samples of metric cable next time I'm over on that side of the pond...

[This message has been edited by SteveFehr (edited 07-23-2006).]

#14 is 2.08 mm2
@12 is 3.31 mm2

Per table 8

Thanks for the replys all I can say is I learned something new today.

Paul thanks for the correction. I got my vernier gauge out and measured the diameter of some T&E cores
1mm = 1.1mm
2.5mm = 1.7mm
6mm = 3.1mm
(20 years and still making asumptions tut tut)

C-H managed to follow "AWG" and "Metric" but just could not see the point of "Circular Mils" Who uses "kcmil" as a measument?

Americans use kcmils or MCM for all sizes larger than 4/0 AWG. The smallest kcmil size is 250 kcmil, 127 mm2. Question for the American members, is kcmil used much outside electrics at all?

I'd never seen kcmil or MCM used anywhere except for commercial electrical power cable. Everyone else uses "normal" units.

If you do a google search and start filtering out electrical terms, you see the hits go down and down and down until there are only a handful of sites left, and then only because of the way they typed some of the key words: http://www.google.com/search?hl=en&lr=&q=kcmil+-electric+-awg+-cable+-conductor+-copper+-lugs+-crimp+-wire+-splice+-%236awg

One thing I have noticed over here, is that Automotive wire, in the heavier sizes, (for them over-powered Car-Audio systems) is sold in #8, #6 and #4 sizes.
Unusual in a place that uses metrics.

Trumpy, could that have something to do with that "World Market" rumor that's been going around for a time???

The 'auto wire' is probably a different strand layout then our building wire?

That red/black 'TE' come in stranded, or only solid??

John