Hi, I’m building my first board and finished planning out wiring diagram. If someone could glance over it and point out if I made any mistakes or can make it better it would be great, thanks!
Some more info:
The bms is LLT rated for 20A on discharge and 18 on charge (hence the fuse sizes). I also want the entire battery to be easily removed from the case, so there is an extra pair of XT90s between the battery and the ESC, I’m installing the esc in separate enclosure on the tail and will route the cables under the trampa wings and try to make everything as waterproof as possible.
Usually would have the loop key after the battery disconnect so the harness stays with the board, and you generally want the charge port before the loop key so you can charge it with the board off
The LLT bms has a software disable for charge and discharge separately so you don’t need a loop key to lock it out
My initial idea was to use loopkey as a way to be able to physically cut the power to the rest of the board but it does indeed make a lot more sense to put charging on the battery side. The ESC I’m going to use does have the nice external power switch for internal anti-spark tho so I’d probably mostly pull out the loopkey to do some work on the board.
I think I’ll still go with 16AWG for the charging and lights simply because I have some on hand.
Edit: actually you might want a lower current charge fuse, if the charge port isn’t rated to carry that much current you want the fuse to blow before you melt the charger
Personally I’d use an XT30 for one of the connectors so you don’t accidentally plug stuff in wrong
Of course it’s possible, and we all want to flex. When someone is asking for help on a first build, they’re not going to pull this off unless they’re already an expert-level solderer. In addition to that, what is 8AWG really buying you, especially on a first build. You’re not going to be using that much power if you’re not towing a car. It would seem to be mostly buying you heartache and pain in your journey to have a working DIY first build, and little else, IMHO.
I ordered an 8A yzpower charger and the BMS should be able to handle up to 18A, in the end I ordered box of 10A fuses (because I couldn’t find any in the 11A to 18A range locally that weren’t stupidly overpriced) and I’m putting them in the inline holders to make maintenance easier in case they blow.
I guess the same plug for charge and lights is a bit of risk but I’ll color-code them and lights will probably stay connected usually so I think it should be fine.
xt60 as charger port. I already have charger for 12s with xt60 plug and I’m planning on leaving the port inside the peli case to protect it from environment and open it to charge the batteries.
