Only difference to a “proper” connection should be to parallely connect batteries to bms and esc.
How would I do that?
Your recent diagram is already parallel, you’re good
I ran into the same problem a year ago. I bought a BMS for charging and the discharge current limiting was only 30 A, which would have majorly crippled my board. My board is a mountainboard so it requires about twice the power of a skateboard to get it moving.
I had overthought the BMS and somehow assumed that the charging and current limiting function was in the same circuit. There not, they are semi-separate. That what Namasaki meant by “So, I would highly recommend that you connect the BMS for discharge as well as charge”.
I assume your motors can take 2-3 kW per motor. My math says your BMS will limit your power to 1 kW. Your losing about 80% of your motors maximum power.
I’d personally put in at least a switch that would bypass the current limiting function. This way you can flip the switch and if it burns the fuse, then you know you are crippling your board.
Though you might be better off taking advice for the others on this board. I have only a 150 A circuit breaker between my ESC and battery. I fried a Flier ESC and at the same time that ruined my battery 
Now I have a pair of VESCs. If you trust your ESC you don’t need to protect your battery.
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Ordered June 27th, got it July 13th (yesterday). Faster than my VESCs, that’s for sure.
Left the obligatory “A+++ SELLER!!! WOULD BUY AGAIN!!!1”
I got mine today!
From battery supports?
@Jinra I’m in the process of packing a pack as well, where would I put a on/off switch to cut off power to the board in this set up?
some bms’s come with an e switch so preferably there. If not, after the bms and before the voltmeter.
This may very well be a silly question but if i intend to use a BMS for charging but discharge through a bypass, will the e-switch on the BMS be rendered useless? I believe the answer is yes once I thought about it but I dont know much about how these things work just yet. If that is the case though, I will have to get a higher amp BMS (80 continuous discharge for 10s4p using Samsung 18650 25R) to be able to use the e-switch to turn off the board?
@lowGuido can confirm BMS question. @JuniorPotato93 is your CAD design for the kegel available on thingiverse.
True story.
The CAD will be available today. I made the Thingiverse account yesterday and so it wouldnt let me publish for 24 hours
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Why does it go from 7 wires to 6 wires on the BMS connector? @stuxtruth @Jinra
Apologize if it’s a simpleton question, still figuring out BMSs and whether or not I want to use one or use it for charging only.
the 7th wire is effectly the pack main negative lead. “B-” on the diagram.
Ok, thank you!
Some of the BMSs I have looked at have a B- or B0 balance cable in addition to another spot on the board for B- which is why I was confused about dropping to 6 cables. The Evolve BMS is like this https://endless-sphere.com/forums/viewtopic.php?t=70435#p1064672
I guess the one the @stuxtruth must not be set up that way.
To bring this subject into light again…
I’d like to make a charge only BMS set up for my 6S2P setup with venom lipo’s (slightly nicer zippys) The single plug is going to be a must for me since I will be at college. I want to use the BMS to ONLY CHARGE, not for discharging, so I would end up getting a less expensive BMS.
I made a circuit diagram that you will see below. From what I can tell, this circuit is for both charging and discharging, which would require me to have a bms with a high discharge value so it won’t limit my motor power. How would I go about making it for charging only, with a bypass so I can avoid the BMS current limit?
Also, I am planning on using one of these adapters to connect my two lipo packs into effectively a 6s pack so the BMS will see it as a 6s. Would this work, or will I have to wire the balance connectors myself? http://www.hobbyking.com/hobbyking/store/_9910__2_x_3S_gt_6S_Splitter_JST_XH_5pcs_bag.html
And if I do have to wire it myself, is this diagram correct?
And finally here is the circuit diagram
Please check to make sure that diagram makes sense. The bms I am planning on using is something along the line of this: Ebay
It is cheap and probably has less than perfect build specs, but since it is (as planned) going to be for nothing other than balancing the cells while charging I do not see a problem. If there is one, let me know and I will pick up the same bms that strux had.
EDIT-
I should mention I have had all of this figured out by now, just haven’t updated this thread.
To run a Charge Only BMS you will need to follow the diagram above but run the negative from the esc/motor straight to the battery instead of to P-. You will still attach the negative to B-, but not P-. The charger does still attach to P- however.
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I’m having some confusion too with the wiring of these BMS’s.
I have ordered the 12s 60A BMS and am looking for pointers on the wiring.
This is the diagram that they provide:
This is a quick diagram that I have set up as I understand it (Excuse the rushed-ness!).
(I labeled it as 80A but I have ordered the 60A).
Is this correct? The balance cables took some mind bending but I think they’re correctly wired. If I wanted to use the BMS as charge only (incase the 60A limit is too low for my setup) how would I modify this wiring?
Also, does the AWG of the wiring to the charge port need to be low gauge? Or does it only need to handle the charge current coming in through the charger?
Hope someone out there has used something similar!
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