> For the same wattage, the current is half, so equal to the wire size.

I'm not totally clear what you are trying to say, but it is harder to make a
240V bulb at the same wattage as a 120V bulb.  The 240V bulb must have 4
times the resistance of the 120V bulb to end up with the same wattage.  This
means the bulb manufacturer has two choices, make the filament longer or
thinner.  Thinner makes the filament more fragile and reduces bulb life for
obvious reasons.  Longer spreads the same power over more filament, reducing
its temperature and therefore efficiency, which can be made up for by
thinning the filament...


********************************************************************
Olin Lathrop, embedded systems consultant in Littleton Massachusetts
(978) 742-9014, olin@embedinc.com, http://www.embedinc.com

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