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4S BMS cutoff conditions and "reset"
#11
Most cheap bms trigger at around 4.25-4.3v and within a second
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#12
(06-20-2019, 08:43 AM)bmcmullin Wrote: I'm going to be embarrased if something is connected wrong and/or I have a gross misunderstanding of this domain but I'll happily admit failure if it leads me to enlightenment and a proper understanding of this science.  I am very grateful for your assistance.  I wish I could return the favor.

I think we need a drawing/schematic of how 'you' have everything hooked up. This might help us clarify things up.

So for added info:
Voltages between 'parallel' cells can not have different voltages, not possible. Voltages between 'series' connected cells/packs can have different voltages, and this is what I was assuming when you stated different voltage readings earlier.

It is still possible the bms can be wired up exactly as it's supposed to be, and still not function as intended. Unfortunately, they can't be all be tested before they leave the factory, especially chinesium brands.
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#13
See the photos of the pack with the BMS.  I think you can see the wiring.   Update: I added a link to a photo of a commercial 4S8P pack here https://voltaplex.com/4s8p-14.4v-23.04ah...-pf-cuboid. I think I see a potential problem.  In my pack I don't have strips going from end-to-end on all banks.

 
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