Battery cutoff settings

I still have some juice left if my pack, I will charge it with the brick on Tuesday and I will leave it to balance for 45 min or so. I wish I had cell checker so I could keep an eye on each cell while is charging and balancing. Let me know how it preforms balancing with your brick. I’m curious.

Shouldn’t balancing only commence once individual cells reach 4.2V ? Above values are below 4.2.

That wouldn’t work anyway because you have to turn the switch off and disconect the bms balance leads in order to plug in the cell checker.

Please go back and read edit

I could use parallel balance leads, someone here recommended this kind of set up.

It would be fine to add a loop key as long as it downstream from the pos charge wire. So that the loop key doesn’t disconnect the pos charge wire. After the your charger goes green, turn it off and unplug it and leave the bms e-switch on for balancing.

Ok, yes, that would work.

@Namasaki it could just be the power draw of the BMS bringing them down, not any balancing function.

@scepterr After turning my bms on for the 3rd time, it brought the total pack voltage down to 41.8v Some numbers rounded up and some rounded down. 4.18 4.18 4.19 4.19 4.19 4.19 4.19 4.19 4.18 4.18

Hard to say for sure. Still even the original balancing is adequate in my opinion.

And this concludes my testing session for today.

So you would not put the the loopkey in series between P- on the BMS, and - in the vescs ? You would take the positive Wire to the VESC after the charge wire

Just for clarification - power adapter wasn’t on/connected, just board itself including Vesc?

Oh your right, what was I thinking? Yes put it on the negative main between the P- and Vesc negative.

If by power adapter you mean the charger then yes, it was off and disconnected.

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Thanks I very appreciate your help.

I just did a test charge for the very first time, and all seems to be working fine. I could monitor all the cells voltage with my multimeter and temporary connectors. And they all seems to charge pretty equally :smiley: Without any load on P- and plus from the battery, with the E-switch off. I measure close to bat voltage between plus on the battery and P-. I have not received my focboxes yet. Do you think it’s gonna drain my battery over time ?

I knew it was wrong thats why I posted pictures. I read/watched videos but got different numbers thats why I asked.

I wasn’t mocking you mate, I was mocking everyone else for not seeing it or mentioning it to you :wink:

It’s still reading full pack voltage because there is no load to pull it down. As long as the bms is off your battery should not drain down.

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Actually i dont think you are right. After 45min, the voltage has dropped 0.02v. I had an old car bulb laying arround, and now the voltage dropped to 0v. And the voltage seems stable for now.

Sorry, fell asleep :sleeping:

True, you can increase your batt regen to 40A max, for safety maybe 35A. I have 10s1p Lipo 10Ah with 5c and my setting is 40A.

@Jdubb121212 your Motor min setting is -60A, I would decrease it to -40A or less. Batt max 25A seems very safe, maybe you can increase it a bit if you need more power sometimes (if you don’t push full throttle too often or climb epic hills). I guess your max cont. battery output is 40A, the cells get warm above 20A and hot when they reach 40A. I’m not sure about your batt min setting, now it’s -20A, theoretically your 12s2p can handle about 8A only but I’ve read several times that in real world the regen power isn’t that high as in settings, so it could be OK.

My battery cut off settings are (Lipo and Li-ion): Cut off start 35v Cut off end 32V

I try to reach home above 36V but sometimes I go down to 32V. But anyway the time frame is very tiny from 35V to 32V, some blinks of an eye

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