After 2 months of activity my bms smart 12/200 stopped working after I disconnected the gnd and reinserted it hoping to do a reset because I had noticed that it only charged 30A despite having set a 100A fuse. Now I have put a bms 12/100 that I had purchased in addition for safety, luckily, otherwise I would have been in trouble during the cruise. At this point I believe that the low current problem is caused by a fault in the alternator, which is also quite new, it is only 2 years old. What could have happened? thanks
With this BMS the alternator charging is passive, that means that the input voltage (from the alternator) needs to be higher than the voltage of the lithium battery.
The lower the difference between that voltages the lower is the charging current.
Higher difference means higher charging current.
“Smart” alternators of new cars often reduce the voltage quickly after the start causing a low current.
So you should check the voltage coming from the alternator.
the voltage is good, the alternator delivers up to 14.6v and I also have the sterling power alternator to battery that controls the charging. When I first mounted it worked well, with a 100A fuse it delivered 90A, then I put in an 80A fuse and it continued to deliver 90A strangely, obviously also setting the new fuse inside the victron app, then I replaced the fuse with a 60A one and I started to see 40A of charging, but I wanted to go back to having 70A and by replacing the 80A fuse I noticed that the alternator does not deliver more than 40A
I wonder if using a Sterling alternator to battery charger AND the Victron BMS is a good idea because you now have 2 devices that are trying to control battery charging. I am not surprised when you say that you tried a smaller fuse that the current did not reduce, the AtoB charger will be interacting differently compared to an alternator on its own. If your alternator is delivering 14.6V on its own then I recommend testing the performance of the new BMS without the AtoB.
of course i tested the alternator without sterling, however the problem was present.