3 AAA to 2 CR123 conversion?

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C

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so i have a light that has a cree emmiter in it and i was wondering if they will fit, can i drop in 2 cr123's and run it off that or will the extra voltage be to much for it to handle from the 3 AAA?
 
Linger

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Don't do it.
read about 3aaa and why it's a cheap (for manufacturor) and bad (for user) configuration. In brief it may rely upon higher resistance of components and high internal resistance (thus low ma output) of the cells to keep the light running. A single cr123 may be too much (with a spacer). Two will definately over volt the poor thing.
 
Lynx_Arc

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I don't think two 123 primaries will fit well in a 3AAA light and the voltage of 6.4v would fry even high power LEDs so you would need to add a regulating circuit. A single 123 primary would not drive the LEDs fully but perhaps at most half brightness. Your best bet it to just sell the light and put the money towards a 123 cell light
 
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Lynx_Arc said:
I don't think two 123 primaries will fit well in a 3AAA light and the voltage of 6.4v would fry even high power LEDs so you would need to add a regulating circuit. A single 123 primary would not drive the LEDs fully but perhaps at most half brightness. Your best bet it to just sell the light and put the money towards a 123 cell light
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well ive got a fenix pd30 already and im very happy with it. this light is jsut for my car and it sits there through -40C weather and i figured if i could get some more run time out of it why not, so running on 3AAA is not a huge deal. thanks for the advise guys
 
Lynx_Arc

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most 3AAA lights are designed for primaries (alkaline or heavy duty) and the runtime is already increased by the batteries unable to provide the current the led can take. to put batteries able to provide more current will most likely decrease runtime while increasing output. The only way to change that is to change the circuitry either adding a resistor into it to throttle the current down more or a regulator. If it has a high power led in it I would just try lithium AAA primaries and be content you will have less runtime but worry less about the batteries.
 
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Lynx_Arc said:
most 3AAA lights are designed for primaries (alkaline or heavy duty) and the runtime is already increased by the batteries unable to provide the current the led can take. to put batteries able to provide more current will most likely decrease runtime while increasing output. The only way to change that is to change the circuitry either adding a resistor into it to throttle the current down more or a regulator. If it has a high power led in it I would just try lithium AAA primaries and be content you will have less runtime but worry less about the batteries.
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well im not worried about the batteries actually dieing from from the cold. ive had batteries sit in the cold all winter and they survived jsut fine
 
Lynx_Arc

Lynx_Arc

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the cold only causes problems when water condenses on batteries, but heat can be trouble here cooking batteries in 100+ degree temps making car temps perhaps 130-150 degrees
 
C

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Lynx_Arc said:
the cold only causes problems when water condenses on batteries, but heat can be trouble here cooking batteries in 100+ degree temps making car temps perhaps 130-150 degrees
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meh im not to worried, my poor gps has survived being left on the dash and after it was to hot to even hold
 
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