Yes, if you are bypassing the BMS for discharge, a lot of times you can leave B- unhooked on the BMS because it directly connects to B0 (if that BMS has a B0, not all do)
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Yep, I like to just connect them together anyway, just in case it’s isolated. Pretty sure most Chinese bms use a b0 and b- most bestech and supower don’t if I recall
I just look at the PCB and if see they are connected on the copper and measure that they are connected on the copper, adding another wire is just one more thing that could rub and short out
The next problem with charging like that without the extra wire is the connector is rated for probs 4a max
I can see how that can happen. However all the manufacturer’s diagrams I have seen, they show the b- connected (if the BMS is of a decent charge rating). Guys I think you can agree that there are not many stupid BMS manufacturers that would rate their BMSs for 10-15-20A continuous charge current if the current went through the puny balance leads when wired according to their instructions. Can you make it go through at least one balance lead? Probably yes, but in that case you are wiring it wrong.
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I usually charge at 2A but sometimes I will juice at 4A if I’m not at home. At home I always have another board charged anyway and would charge at 500mA if I could
Wrong to you, for your needs – maybe, I will give you that. But that’s about all. Definitely not wrong in all situations. Which is the whole thing I was saying about generalising.
I guess it depends how you looks at it. I actually wire mine properly anyway, I was just trying to show it can be wired in a way that the leads do handle current
No, just stop it. I’ve had enough. It’s time for change
Stop using a f’ing Z in your words, bloody Americans. Use a S from now on
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This is something we can both agree on.
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In Aus nowadays if you take an exam and use either spelling it is classed as correct as long as it’s consistent. Just shows nobody knows what the heck to use
It’s actually hilarious you pointed that out, because I typed an “S” then when I proofread it I changed it to “Z” because that’s how my fellow 'Muricans do it. But now I changed it back to “S” how it’s supposed to be and I think of it in my head.
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Imagine what this does to a non native English speaker such as myself. I am confused. Still calling it aluminium though 'cause it sounds cooler.
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I hate it when people call it aluminum
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I see the balance wire placement issue, I have resolved it in the image and replaced it in the linked post. I don’t know how that happened, its even correct in my work document. I guess I had versioning issue.
The Bestech D140 doesn’t have a B0, only a B- which is logically identical to B1. I specifically created the illustration with the D140 in mind as it’s become very popular as of late.
Most importantly, if you see a diagram issue (and I’m not talking specifically to you @b264, rather to everyone) point it out. Lots of people depend on these diagrams for construction and a defective diagram can cost somebody a lot of money and fingers.
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Hi all! Been a busy day. While this has been an interesting read, I’m not really any closer to answering the question of what amperage I should charge my pack at. Now I even have developed some degree of angst as too how to set up my BMS 
Yes, 2a is safest, and 4a is possible… But if there is no consequences to using 6,8,10 or more, why not do it? Not too bothered about years of life out of the pack.
Actually I think a charger with adjustable amperage would be the sweet spot. No hurry? 0.5a. Busy day? BOOM, 12a. Know any of those? 
And thanks a bunch for being so detailed in answering, I learn so much from this forum! No generaliSing 
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Still wrong Mike. Gotta connect the B12 + pole to the BMS.
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From what point to what point?
You can make an adjustable charger using a boost converter, watt meter and 24v+ power supply. Or you can go reverse and buy a 48v psu and a buck converter, some have integrated watt meter type things too. Just make sure to get a cc/cv charger
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The pos of the battery pack should be your last connection b12 if it’s 12s