David Nebenzahl wrote:
....
That's not true. Conductors are rated at a certain current regardless of
their length.
....
Not exactly so--look at the voltage drop tables; at a given voltage the
drop becomes excessive at a minimum conductor size and a larger
conductor is required.

All these points have been considered--in essence, the answer is that
the individual appliance/light/whatever has conductors sized
specifically for the load.

A 100W bulb, for example, on the 15A 14ga circuit doesn't need 14ga
because it draws only 1A (in round numbers)--the circuit wiring is
required to be larger to account for the loading of all devices in
simultaneous usage on the circuit.

Also, again, NEC specifically covers the wiring not the end devices;
they're under other guidelines such as UL, etc., ...

In the end, there's no increased risk in common usage as long as you
don't do something that is in obvious contravention to intended use--put
a 300W bulb in a 25W rated fixture or 3 1000W hair driers on a 25-ft
16ga light-duty extension cord, say. Sure, one _can_ do stupid, it's
presumed the Darwin rule will take care of that...

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