12s battery has 12 negative terminals, black wire lands on the first one, the next white wire lands on the next one and so on, last red wire lands on main battery positive terminal. Black wire is the one that you think is missing. The wires in the lower left are temperature sensors
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Thank you, I understand. 2 more questions.
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so the negative terminals in the drawings are located in between the packs - on the metal thing that bridges/connects them…is that correct? (also is the drawing ive now ammended 100% correct?
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…where is the ESC plug/soldered on? - or do they not run through the BMS (I can’t’ see why the ESC would need to go through the BMS)
…and i guess the temp sensors don;t need to be plugged into anything…they’re basically good to go as-is?
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Looks correct to me.
Did the BMS not include a wiring diagram? Usually they can give you an idea of where the other wires go as well
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nope. came in bubble wrap and nothing else. oh i got a free sticker too
Oh rip haha
This post
has a diagram in it that I found for a similar smart bms to mine, I used that to remind myself of basic layout. Keep in mind this diagram in the post is wired “for discharge” as in the battery current out to the load goes through the bms, if you want to wire “for charge only” it’s a little different, let me know if you need more detail
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will def let you know if i need help, most certainly will when the parts arrive lol. Can i ask how thick your stacked 30q pack was in total (i.e. finished wth fishapaper and all the other stuff)
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I’d have to measure it, but off the top of my head somewhere around 30mm. I think the cutout is like 10mm deep and then the BB double stack is like 28mm deep or something like that
Then I added neoprene on one side and thin foam on the other and overall it’s a snug fit, with the gasket around the enclosure.
Don’t worry I’ll be updating the build thread tonight… hint hint I basically finished it lol just didn’t wanna post “almost finished” pics as to not spoil it until it’s done and I take real pics of it
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ah ok. my double stack NESE is goinf to be 40mm all-in…
looking forwrad to seeing the thread!
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I don’t believe this is enough of a difference between the soft and full cut. I run 3.4 soft and 3.15 full. You dont want to hit the soft cutoff and then sag below the full cut on the last hill home or something.
Hmm fair enough. Don’t know exactly how much power gets cut at soft cutoff either, it was pretty dramatic on my last board
It’s a gradient. duty_cycle is cut by X% where X is 0% at cutoff start (aka soft) and 100% at cutoff end. (aka hard)
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Oh cool thanks for that, I always wondered. So basically it is actually beneficial to have it like @A13XR3 suggests, because you have more time to realize that you can’t go as fast - although at the same time, if you aren’t traveling top speed I could see not noticing it till it’s too late anyway
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I don’t seem to be able to edit my post so I’ll correct it here. Most of what I said is true except I realise capacity is only half the story when talking about the actual amount of energy coming out of the cell. Because the voltage is lower during higher discharge, the total Wh out of the cell is lower:
The Wh has an 8% difference with a .6A and 10A load
So no you don’t get (noticeably)less capacity out of the battery by riding harder but you do get less energy.
are there any recommended battery builders in the UK?
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Apexcustoms @Lee_Wright https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.electricskateboarding.co.uk/&ved=2ahUKEwjLqN2VwvjqAhWQXM0KHUgjDZMQFjABegQIARAC&usg=AOvVaw3sXrPZyAHQ-FqG8_1O83aU
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Hey bro, we can certainly hook you up with a battery - what do you need?
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What would happen if you packed a 12s7p or 12s8p on one of those PCBs? would it work it just break?
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I don’t see why it wouldn’t work, you would just need to make your own p group nickel tabs.
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