"Eisboch" wrote in message
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"Bill McKee" wrote in message
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"Eisboch" wrote in message
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wrote in message
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First version, otherwise why use 6 resistors instead of one single
lower ohmage one of higher power.


I was trying to roughly calculate the power requirements. You said 600
ohm resistors, correct? The voltage drop on the LED will be minimal
when forward biased or "on", so each branch must be about .02 amps,
times six equals .12 amps, so the power must be about 12v times .12 or
about 1.4 watts. Probably a bit more when you factor in the LED drop,
whatever it is. Significantly less than a regular light bulb!

Eisboch


Most LED's are in the 400mw range.

Does that include the new, high powered ones? The are being used on
trucks for brake lights, turn signals and other places to replace bulbs.
They are incredibly bright. Maybe the brightness is due to optics being
used, like a Fresnel lens or something.

Eisboch




Maybe a little more, but not much. The trucks use them for the same reason
I went to LED's on the boat trailer. Longevity. they do not have to waste
time, explaining to the cops why the clearance lights are not all working.
They are very voltage sensitive. to little voltage, not enough current and
the LED is black, increase voltage to a point and they get brighter,
increase more and they start getting dimmer, and too much voltage and they
are bright for a few milliseconds, and the magic smoke is released.