Quote:
Originally Posted by wintermute
Interesting led lighting danielwritesback. are you using different colours to get a more natural light?
Tony.
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Thanks!
It is more natural indeed, but that isn't the main purpose and wasn't the reason.
Functions:
1). Avoid RV fire.
13.8v subtract (3+3+2+3) = 11v with cutoff at 10.8v for battery protection. The amber example is purchased extra sturdy with 1/3rd more current capacity than either the warm white or white. The resistor is sized for 42% of max led current draw @ 13.5vdc. Use led calculator with 9v led and subtract 2v from the power supply figure and subtract more than half the current capacity to get resistor values that don't overrun. Longevity concerns double expenses but there is no waste heat.
It seems to be efficient.
2). Facilitate eyeball.
The multi-bandwidth light increases the resolution power of the eye. This makes the light appear far more powerful with much less glare.
Precursor: With commercial LED products, the combination of the sort of weak warm white with the horrible glare bright white averages out to work reasonably if the voltage is adjusted to avoid setting the RV or car ablaze. Commercial LED replacement bulbs can be equipped with 2x series 1n5405 series to an MR (0.5 to 0.7 flexible drop) power diodes to remove fire hazard waste heat. For the handmade alternative, I chose a sturdy Amber LED instead of lighting up black diodes.
Option: If amber led's with 1/3rd more current ability cannot be sourced, diode paralleling can be done. For example 2 diodes in parallel adds 50% more current handling. This is like: (20ma warm white + 20ma white + (20ma amber//20ma amber) + 20ma white) = 11v The amber of 2v attracts 1/3rd more current than the 3v white diodes. Longevity for 20ma led occurs at 9.5ma and less. Of course it would be better to source 30ma amber to go with 20ma white and likewise source 150ma amber to go with 100ma white.
Hidden caveat: With mobile applications it is vital to measure voltage with the multimeter set on AC and add that figure to whatever the multimeter reads for DC. For example, your RV might add up to 18v. In this case, the span becomes 11vdc to 18vac. The led calculator uses 9v led to 16v power source (subtract the amber from both so that the spreadsheet works). The LED's must not pass half of their current capacity. That will get expensive with derating into underrun.
The quick fix is to move the lighting circuit wire over to "direct to battery" for power smoothing the lighting circuit. In that case, it may be necessary to move any heavy duty appliances off of lighting circuits.
It is also necessary to measure mobile applications with the engine running. No mobile application uses 12v unless a dead battery needs charged.
Its a really bad math problem to use commercial LED replacement bulbs since they have push for power design at 12v which is not suited to a 13.8vdc, 14.8v car, or 18vac vehicle with a big tank of gasoline. Much unlike the commercial products, my design theme was primarily for avoiding fire instead of causing it. However, commercial bulbs, 3 series white, also drain batteries down to 9v, which is battery damage. So my 11v design avoids that problem too.
Yes it was all problem avoidance and very little light.
This LED technology is not for use anywhere a florescent should be used.
However, the LED's work well for smaller, closer areas where you can apply the inverse square law as a boost (max application = chandelier).
And, accessory LED lighting in the home helps efficiency mainly by decreasing the run-time of large overhead florescent lights.
I'm just sayin, don't break your wallet over miniature night lights.
Each of the wide angle lights shown is able to light a patch of kitchen counter top about the width of a cabinet door. With the operating distance (height above countertop) at 17" the inverse square law has made an extreme boost.
They are not applicable at ceiling height because you would have to pave over most of the ceiling with efficiency same as or poorer than a florescent. So, I don't have any on the ceiling.
