where do lumens top out on 1 cr123 cell??
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kakster
Flashlight Enthusiast
The ARC4X uses Luxeons hand selected for optimum effenciency, which accounts for its impressive output. I should point out that the actual light itself not that efficient when driven at this level.
As for another single CR123 thats brighter...well, theres been debate about how much juice a single cell can provide, so it will very much depend on the quality of the LED itself.
Having said that, look out for Mr Bulks VIP, and also Dat2zip's next generation BadBoy regulator, which promises very high performance.
As for another single CR123 thats brighter...well, theres been debate about how much juice a single cell can provide, so it will very much depend on the quality of the LED itself.
Having said that, look out for Mr Bulks VIP, and also Dat2zip's next generation BadBoy regulator, which promises very high performance.
IsaacHayes
Flashlight Enthusiast
Very true about emitter selection. Not only flux, but Vf comes into play. As you have to use a boost circuit, a lower Vf luxeon means the circuit doesn't have to pull as much current to boost the voltage, thus more of the cells current is going to the luxeon, and not wasted being "converted" to higher voltage in the circuit.
A T bin red-orange DD could do up to 87 lumens. As for white well, perhaps a LuxIII driven hard could be up around 80...
A T bin red-orange DD could do up to 87 lumens. As for white well, perhaps a LuxIII driven hard could be up around 80...
js
Flashlight Enthusiast
I don't know that much about Luxeons (although I absolutely love my FF w/ MM+ and TY0J lux III) but a few theoretical considerations come to mind. The internal resistance of a 123 is something like 300 mOhms which really limits the theoretical power able to be delivered to a load. The voltage across the terminals would be 3 volts - .3 * i. Thus the power delivered to the load would be 3*i - .3*i^2. To find the maximum take the first derivative and set it to zero: 0 = 3 - .6* i or i = 5 amps. At 5 amps the voltage would be 1.5 volts, and thus the power would be 1.5 volts * 5 amps = 7.5 watts.
OK. So 7.5 watts. Now, so far, the maximum efficiency I have seen is around 30 lumens per watt of bulb lumens. Remeber that what finally comes out the front end will always be less than this. 75 percent is a good round estimate of what makes it out the front. Anyway, 30 * 7.5 *.75= 169 lumens. But not for very long, for sure, if it could even really support a 5 amp draw. SureFire applications seem to indicate that 5 watts per 123 is more or less the most that can be expected, so that would translate into 112 lumens out the front of the torch.
123 cells have built in thermal protection, however, and would probably shut down in a matter of minutes or even seconds when asked to provide this kind of power.
Still, there you have the theoretical maximum, assuming that the true voltage source (=o.c. voltage) in series with a resistor (=internal resistance) is a good model for a battery over all current values. This is not the case, however, as you have to consider electrolyte depletion and other groovy stuff like that which is really beyond my knowledge at the moment.
Eh, take it for what it's worth. Hope this helped.
OK. So 7.5 watts. Now, so far, the maximum efficiency I have seen is around 30 lumens per watt of bulb lumens. Remeber that what finally comes out the front end will always be less than this. 75 percent is a good round estimate of what makes it out the front. Anyway, 30 * 7.5 *.75= 169 lumens. But not for very long, for sure, if it could even really support a 5 amp draw. SureFire applications seem to indicate that 5 watts per 123 is more or less the most that can be expected, so that would translate into 112 lumens out the front of the torch.
123 cells have built in thermal protection, however, and would probably shut down in a matter of minutes or even seconds when asked to provide this kind of power.
Still, there you have the theoretical maximum, assuming that the true voltage source (=o.c. voltage) in series with a resistor (=internal resistance) is a good model for a battery over all current values. This is not the case, however, as you have to consider electrolyte depletion and other groovy stuff like that which is really beyond my knowledge at the moment.
Eh, take it for what it's worth. Hope this helped.
