Not at all. That is the figure you would use if you were to use the wire to construct a wound component. For point to point wiring you could increase the capacity by about a factor of four. Preece and Onderdonk’s equations are much more useful than these capacity charts.
I don't know. Others here probably learned more about electricity their first morning in college than I learned from experience. I know enough of the electrical code to do my job and make it to retirement age. It would've been bad for business if I wired something that killed a farmer. News and rumors travel fast in rural areas.
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On 3/31/2023 7:25 PM, Sid 03 wrote: [...]
[...]Those numbers are from the NEC (National Electric Code) for residential (& commercial?) wiring.
#28 coppr wire has a fusing current of 14.4 amps. It barely gets warm in still free air at 1.5 amp, which is 10:1 current, 100:1 heating.
Which is what I said. 28AWG is 0.32mm diameter - fusing current is approx 80*0.32^1.5=14.5A. If winding an inductor you would limit the current to about 14.5/20 (0.72A), for point to point about 4 times that or 2.9A. But in many situations it's the wiring insulation that sets the current limit.
NFPA NEC
NEC doesn't allow LV on those sizes.
Figure out how much energy you can afford to lose in the wires and choose a size that does better
I agree NEC, but for 90 degree insulation power wiring the NEC rating is
40A for #10, 30A for #12 and 25A for #14 but the maximum current rating they can be used at is what is above. The higher rating can be used for derating like for ambient temp and number of wires in a conduit. Wire rating depends on how the wire is used, like ambient (which I think others have said). Connectors (like lugs) also have a temperature rating.Rating for use in UL industrial control panels (1996) is #28 - 0.8A, #26 - 1A, #24 - 2A, #22 - 3A, #20 - 5A, #18 - 7A, #16 - 10A, #14 -
20A, #12 - 25A, #10 - 40A.
I was surprised #27 is in the NEC for flexible cords (tinsel wire - Christmas tree lights?) at 0.5A. Must need a fused plug. Next larger size is #20.
NEC for #18 flexible cord, 2 current carrying conductors (ground wire doesn't count), the rating is 10A.
I think the general answer is - it depends.
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