A 12S BMS that doesn't stay warm all the time

So I have a 12s5p pack in my board that is managed by a charge only 12s BMS of unknown origin (I bought the board partially complete). Driving the 6380 motors is a Focbox Unity that bypasses the BMS.

Everything works fine, but I’ve noticed that the BMS is ALWAYS warm even if it isn’t charging. My research indicates that the BMS is actually always trying to keep the cells balanced. It appears to me that in order to do this it is constantly draining individual cells to keep all of the voltages close, and the byproduct of this is the generation of heat.

I’d prefer to use a smarter BMS that isn’t a 24/7 voltage vampire. I see the Besttech D140 is sorta the go-to BMS, but does it behave in this same manner? Is there another, better option beside the D140?

Thanks in advance!


From the lack of responses, I’m gathering that either all BMS’ exhibit this behavior, or there is something wrong with mine and I’m one of the few to experience this sort of issue.

Has anyone seen the behavior I describe?

If a bms has a balance function then yes, it will behave that way.

Something you might want to look into, if the bms is constantly trying to balance, you might have unbalanced cells/groups.

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