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07-17-2011, 08:33 AM
| #1 |
| Quarry Creeper Join Date: Nov 2010 Location: land of no rocks
Posts: 438
|  figureing out usage?
can some of you gurus give me a way to figure out how long a small 2s 600mah lipo can power a few leds. 5 3.2v lights wired in parrell with a 10 ohm resistor inline along with the axial stock light set in parrell with those lights. i forgot the specs on the 5 roof lights they are the 5mm radio shack white lights. i thought about wiring in my external lipo cut off but not sure if that would work. being leds they will drain the lipo down to almost 0v
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07-17-2011, 05:49 PM
| #2 |
| I wanna be Dave Join Date: Sep 2005 Location: Houston, TX
Posts: 16,952
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What is the power output of those LEDs? If you know that, then you can use the following: P=(V^2)/R = (I^2)*R and t=R(ohms)*C(farads) 1farad = 1coulomb/volt = 1ampere*second/volt |
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07-17-2011, 06:48 PM
| #3 |
| Pebble Pounder Join Date: May 2011 Location: Spring
Posts: 117
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I run a 3 cell 800 mah lipo for mine. I run 12 LEDs on the body of truck. Then I also run 18 LEDs on 3 strips that I use for night runs. I get a whole nights running out of the pack. Course I never never run from fully charged to drain I am guessing I get 8hrs total time.
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07-17-2011, 07:08 PM
| #4 |
| Got Worms? Join Date: Jun 2009 Location: Golden, CO
Posts: 6,116
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20ma x 5 is 100ma 600/100=6 so 6 hrs of run time. I would suggest running each led with a separate resistor though...if your budget allows, Uberesitors from my store would work best. Because it will always supply (limit) 20 ma to your leds so they won't slowly dim with the drop of voltage...but regular resistors work just fine, will give you longer run time as well. |
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