Hi,
For a lamp (one that is used on a shelf the living room, not a flashlight), desgiend by a friend of mine, I would like to make a led replacement for the current quartz light bulb.
I first wanted to use 3-4 of those $2 CREE leds. But instead of just replacing the bulb with equivalent leds, we decided that it would be interesting to have 10-15 leds, with a mix of cool white and warm white. 15 cree leds would be too expensive. So I think I may use the "epistar" leds that can be found on aliexpress that claim 100 lumen for 3W ( e.g. "this":http://www.aliexpress.com/item/100PCS-LOT-1W-100-110LM-LED-Bulb-IC-SMD-Lamp-Light-Daylight-white-warm-white-cool/724380154.html or "that":http://www.aliexpress.com/item/High-Power-led-1W-led-70-80LM-3-5-3-7V-1W-White-led-lamp-6000/1480073087.html ) , using them at 1W .
Do you know :
-how many lumen per watt I can really expect from those cheap leds ? (efficiency is not a big problem, but I need to calculate how much leds I need and what power supply I need)
-if there is a place to buy more trustable but still cheap leds (are cree Q5 available for $0.10 nowadays ?)
-how reliable those leds can be (luminosity after 50.000 hours, MTBF, ...) ? (at $0.10, I can use 20 of them at half their nominal power if it helps)
Did someone test this kind of leds and have a reliable provider for 50-100 pieces ? (I bought a $1.5 flashlight with a similar led 2 years ago in malaysia : the driver was terrible but the led is rather good with respect to the price of the complete flashlight. The problem is that I did not run it for 25.0000 hours to see if it would fail, output 0.5 lumen per watt when aged, ...)
Thank you, and merry christmas !!
tReg.