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Garage Lighting
In article ,
writes:
In uk.d-i-y, PoP wrote:
BTW, I thought metrication had taken over big time these days? Why are
flourescent lights described in feet then?
Describe 'em how you want: call the 5ft length 150cm if you're being
usefully descriptive, or 2.54 * 60 = 152.4
It really doesn't matter much, since there's no dimension on a
5' tube which measures 5' anyway. The bi-pin tube size measurement
for the original tubes was the spacing between fittings when you
ran them in a continuous line. However, that doesn't apply to
all tube sizes. A quick check of the datasheets shows 18" and 6'
tubes must be based on some other scheme.
In practice, tubes are now quoted in mm sizes, but again, not their
real size -- the conversion is simply to convert the old tube size
to mm using conversion factor 300mm = 1', so a 5' tube is now called
a 1500mm tube. Of course, there's no dimension on it which is 1500mm,
and because 300mm is not really the same as 1', the quoted measurement
is not even the fitting spacing anymore either ;-)
--
Andrew Gabriel
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