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What the World Needs Now -- Long Lasting
LED Night Light
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Previous Issues |
I have
tested a lot of fluorescent and LED type night lights over the years. I have yet to
find one, which is worth what I paid for it. All of the fluorescent lamps died
within a few months. All LED lights faded to the 50% point in one year or less.
A 7 watt incandescent night light lamp does not put out much light and usually dies within
6 months but it is cheap and works the same predictable way from day one to when it dies.
I use a brighter 7 watt lamp in my laundry room, where it runs 24/7. I use that
position for testing the lifetime of various night lights. There is a gray smudge
above the power outlet in that room, left by the puffs of smoke that came out of many of
the night lights I have tested over the years when they died. |
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7W Incandescent Night
Light Bulb |
Plug Mounted LED
Night Light |
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What I
would like to see is a quality light. I don’t mind paying more money for it but I
want it to work more than a year, 5 years would be better. I imagine a white LED
light, which might draw about 2 watts of power and emits a reasonable amount of light.
A light, which emits a bit more than a 7 watt incandescent lamp would be about right.
It needs to use good heat management techniques, so the LED device will last several years
before it hits the 50% |
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intensity point. I think a
reasonable figure of 5 years is doable. An automatic day/night switch would be
nice, so the thing would not be turned on needlessly in the daylight. Am I
asking too much? I can’t imagine that the electronics inside one of these things
would be more complex than a compact fluorescent lamp. Why can’t someone make such a
thing?
Perhaps one way to handle the heat from
the LED and the drive circuit is to use a liquid. Mineral oil or a phase
change wax should do a fine job in drawing away the heat from internal parts toward
the outside, where it can efficiently be dissipated. An example of such a light
is shown below from a company called “Eternal LED.” Perhaps their “Hyralux”
device could be scaled down for a night light application. |
“Eternal LED” Liquid
Cooled LED Light |
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I would think that a single efficient
power LED would work better than a large cluster of smaller devices. This type
of device would also be easier to keep cool. It would require a compact AC to DC
converter, which would supply the LED with a constant current. The are lots of
well designed AC to DC power supply circuits which could be modified for driving a 1
or 2 watt white LED with a constant current. Bias Power makes one such module
but it only produces a fixed voltage. But, it would work for a couple 1W white
LEDs as shown below. The Bias modules are pretty small so they could be slipped
into a plastic housing with ease. |
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Tiny BIAS Power
Supply |
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