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snellemin
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Join Date: May 2007
Location: Houston
05.13.2011, 01:12 AM

Quote:
Originally Posted by pinkpanda3310 View Post
What I would like to know is how does the FMA keep up the charge rate on unbalanced packs when the balance tap is only good for 2 amps?
FMA does it at 3 amps.

Based on my observations, the resistance of the cells go down when you start to pump amperage into your packs. The higher the CC the lower the resistance.
My Acepow get out of balance below 3.7V per cell. When I have 3% capacity in the 4s pack the cells are out of balance, but during charging the the cells voltages match up again at 3.7V per cell. So in a way it self balance itself out at that point. Now once it goes into CV the amprate drops but then your pack in near full and it's just topping it off.
The top off time is a tad longer with me charging at 4.1V per cell cutoff, which comes out to around 91% capacity.

The one thing I don't like of the FMA setup, is the power cables with the blade fuses. Those little fuses get stupid hot at 40A. I added heatsinks onto them. You don't see that everyday.


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