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Old 07-24-2006, 07:35 AM   #1
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Default Calculating milliamps

How do I calculate the milliamps left in a pack after a race? I'm using a Deans cutoff box and a 30A light bar.
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Old 07-24-2006, 07:43 AM   #2
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Basically impossible with such a simple setup. As the lights dim their current draw decreases, so the calculation is about much more than time.

Is milliamps left so important anyway? As long as the car is fast and you make the end of the race, it doesn't really matter. I don't think anyone dumps with 4200's.
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Old 07-24-2006, 07:55 AM   #3
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for arguments sake, if you had a constant current discharge, your equation should look like this:

mAH = (t/3600)*i*1000

where:

t = discharge time in seconds
i = discharge current in amps

eg: at a 30 amp discharge, 100 seconds of runtime = 833 mAH.

alot of racers just go by seconds left in the pack. the above calculation takes into account different discharge rates, so that regardless of what discharger you are using, you can compare your cells to someone elses on theirs.
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Old 07-24-2006, 09:25 AM   #4
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