Since some of you are working on your BMS i guess it is good to explain.
I changed comm lines to soft UTP computer cable. The thing is thin! But it works very good. I now have comms stable through all RPM and up to 200A (havent tried it faster
). However when i start to take off from standstill and just after i stop the comms fall out for a second and then resume. Basically i dont mind this as long as the system restarts. However it shows that some powerful EMI is going on at start and stop.
When i read the ACe5 inverter documentation i found out it injects stoping (countering) current into motor just before 0RPM. Hm...
The other problem just went away by itself
. After i changed comm cables all three banks are balancing normaly. I tested for 1/2 hour, each module is stabilised at cca 800mA current, but transistor is still hot. I/O port disconnects charger at 3,6V as it should, so bottom balancing works.
I noticed something else though. If i have master connected to some cells and i add another bank to the comms in hot swap, the first modules start to balance without indication. I noticed this by smell of hot resistors. However if i restart (unplug 12V) master, everything shows normal, no balancing. A glitch in software maybe?
A