...back to the bike. In the few hours I've had to work on the bike in the last few weeks, I've managed to connect up two of the four battery packs to the large Anderson connectors. I really didn't want to use them because they really are quite big, rated-current-excessive, and surprisingly heavy... but I had to because ten 14 gauge wires (2.08sqmm*10) weren't exactly thrilled at the idea of cramming into a six gauge hole (13.3sqmm) and I didn't want to cut the leads down.
I must say I'm not terribly impressed with the stiffness of the wires. I tried to make all the wire lengths the same length to their respective mates, but one connector ended up being 1/4" shorter than all the others and now it likes to come unplugged. I'm definitely going to need to find a way to prevent mechanical separation... not sure what yet; I've found solutions for Anderson pairs, but not single connections. I'm pretty sure this is going to be an issue unless I decide to purchase 20 more sets of connectors along with a much more flexible gauge wiring. I hope it doesn't come to this, but I'm confident it will.
Anyways, that's what I'm going to try to prevent from having to happen while I wait for my missing link to get here: the motor controller hasn't shown up, but the motor sure did:
Being an engineer, the first thing I did was open it up and play around with the magnets. Being an engineer, the second thing I did was make it better by cutting off the 14 gauge wires that came with it in anticipation that I'll find my roll of solder so I can solder the beefier 10 gauge leads onto it.
This will increase the surface area per phase 2.5 times, resulting in a total 'to-motor' surface area of 15.75 sqmm, which equates to an NEC ampacity rating of 55 amps continuous. Unfortunately, the larger diameter wires don't fit through the shaft and therefore don't route all the way to the motor coils, which results in about 5 inches of 14 gauge wire rated at only 30 amps continuous. Since BMC only rates this motor to 21 amps, I'll need to be careful to not full throttle the bike continuously, as the motor controller can provide up to 50 amps continuous. I temperature sensor near the smaller wires is probably in order.
Also, I'm still looking into where I'm going to fuse these batteries. Ideally, I'd like a fuse between each bank of batteries, but somehow I feel that isn't going to happen. I would venture a guess that I initially have only a single fuse right at the motor controller, leaving the whole battery bank ripe to sustained shorting if anything goes wrong :). For now, I'll just assume any short will cauterize itself thanks to the 2800 amps this pack can theoretically source. Any 14 gauge wire that finds itself with an ill-colored matching should simply cease to exist in a brilliant flash of smoke.*
*One can hope.
