Originally Posted by
genel
The 12V AC spec implies (at least to me) that there is definitely some type of bridge and voltage regulator inside the bulb package. Remember that the actual physical diode will never have a voltage drop more then a few volts, so they have to control this somehow.
Naturally. I was thinking more along the lines of a linear regulator being used instead of a switching circuit somewhere early in the power handling. Of course if not sized to be only a very small drop this would seriously degrade efficiency, so it would seem unlikely to me that they would use such a thing.
Originally Posted by
genel
A heat test showed that after 15 minutes in my garage the package was not noticeably warmer. LED's are primarily killed by heat, the reason that we're getting increasingly bright LED's is primarily better designs for heat dissipation. Since they're all rated for 10's of thousands of hours, a bike light that reduces the life span by as much as 90 percent is still good for the 100 hours or so I use it per year. It would be nice if one could get a schematic of whats inside but I'm not goning to hold my breath.
Very much agreed. As indicated above, the heat I was wondering about would be rather significant, so the feel-it-with-the-hand test seems likely to be good enough.
On some other LED lights for area lighting I have some experience with (120 or 277VAC supply), the biggest lifespan issue they are having is with the driver circuitry, and the company has actually made the driver replaceable in at least some of their lights. I would expect this to be the source of reduced lifespan, especially as you aren't getting increased heat.
Originally Posted by
genel
I'm kinda hoping the 3 watt bulb fails first so I have an excuse to buy another 6 watt.
Originally Posted by
genel
The concern for battery life is real. But LIPO battery's are only good for a couple of hundred recharges in a year or maybe two any way, before they're at 75% capacity. I'm planning on Woot having the XP16000 on sale by then!
Thanks for your comments!!!
Well, if you aren't getting increased heat in your bulbs, then I, with my somewhat limited knowledge, see no reason to expect any noticable shortening of battery life or lightset runtime per charge. Congratulations on good lights.
I meanwhile have ordered a few more parts to improve my setup, and will hopefully be putting the first stage together in a week or so.
Tor