Thread: LEDs
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Terry Spragg
 
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Doug Dotson wrote:

West Marine has a pretty good selection of LED lights.

Doug
s/v Callista

"sel1" wrote in message
...

Just curious...

Has anyone checked out using low voltage white LEDs for lighting in a
boat?
Is this economically (or otherwise)feasible? I understand that they draw
very low voltage/current making them real easy on batteries while
providing
lots of light.


The cheapest source for white LEDs at present seems to be salvage
from solar yard lights on sale.

OEMs are buying them all up in bulk, I guess, I have not yet seen
any at radio shack, or even my parts wholesaler catalogues.

Sell your tungsten stocks, solid state lights are here. Soon, they
will be a few cents each and plentiful.

Each LED consumes about 80 milliamps at 1.6 volts or so. They may
be strung in series so that 5 would require 8.1 volts or so to
ignite, and require a specific resistor in series in the range of a
couple hundreds of ohms to protect the devices from overcurrent, as
they cannot protect themselves or control current in the way we
usually think with ohm's law, as they have conductive
characteristics quite different from resistors, incandescent or
otherwise. More like a gas discharge tube, really. You could mix and
match red, green and blue to approximate white light. They can be
dimmed easily using a rheostat. They are polarised, so require
connection in the right direction, anode to positive. Reverse
connection means they just don't conduct or light up unless exposed
to excessive voltage, in which case they melt and fuse to become an
open circuit. They can be driven from an A.C. source, conducting
like rectifiers.

Yes, they are much more efficient than regular lamps, consuming
about 1/10 the power for equivalent light output, but, at the
present state of the art, high intensity leds are not really very
bright. For low lighting levels, especially low level red night
lights, they are ideal.

Terry K