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I used simple statistics to improve capacity testing by +/-65mAh
#1
And I made a video about it ;-)



TL;DW - compare the average of all cells tested to the average of only those tests in a particular bay.  This will give you an amount you should offset the tested mAh capacity.  Starting voltage doesn't really seem to matter, assuming it's in a reasonable range like 4.15-4.25.
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#2
Nice work. I though think you then need to add another parameter and lower it a certain % on each cell. The Opus is generally off by up to 100mAh + so in the end your values should go down (Compare to high end iChargers and other RC related chargers/testers)
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#3
(09-16-2018, 08:50 AM)daromer Wrote: Nice work. I though think you then need to add another parameter and lower it a certain % on each cell. The Opus is generally off by up to 100mAh + so in the end your values should go down (Compare to high end iChargers and other RC related chargers/testers)

That's a good point; I also noticed that the test varied a lot with discharging current.

However, would that really affect my matching?  The proportional difference between the cells would be the same, right?
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#4
I'd love to see somebody figure out how to correct the difference in voltage readings for the C3100's. One of mine shows a .04v difference from the others. Travis said in Discord that the voltage doesn't seem to matter much, but when a charged cell reads 4.16v in one charger, but 4.20 in another, it sure feels like something that needs to be adjusted.

When capacity testing, I've taken to using whichever charger / bay gives me 4.18 to 4.20 volts for a given cell. (the most common voltages I'm seeing)
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#5
Travis: for pure sorting then the real number doesnt matter much no Smile Thats how I run and make my packs and so far it worked fine.
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