I am building my endgame ebike with a modded QS205, Fox 40 fork, Hope 4 V3's, 18650.lt snap-fit pack of 21s14p 30Q cells, and ASI BAC8000 on a Qulbix 140 frame. 4th >10kW build. Been spending the last 4 months trying to get this controller working, unfortunately. First bench test, I realized I could not connect via USB or bluetooth... it was DOA. 3 months after the RMA, I have a new replacement BAC8000. I used Alan's "Ebike Master Switch" design as a precharge/killswitch, which worked excellent on the first controller and brought the controller terminals up to battery voltage in ~2 seconds.
I tried to bench test the new controller, and now I can connect to it fine via USB or bluetooth, but it blew up my master switch when trying to precharge the battery connections. So I made a dumb 80-ohm, 80-watt ceramic resistor grid precharge line that I expected to be overkill, only to find that even ~1 amp will not precharge the controller-- it only brings the positive terminal to 1.2 volts! No wonder my master switch poofed! First time I tried to use this precharge, I definitely made a big arc and got a puff of smoke from one of my three 100-amp breakers.
- Has anyone else ever had a controller fail in such a way that they cannot precharge the battery connections? Disconnecting the hubmotor phasewires or throttle connections does nothing.
- How do I know if I need to replace my breaker now that I've almost certainly damaged the contacts by arcing? Check resistance?