I try to figure out, if the behaviour I see is per design or not. In my van I have installed a Victron LifePo4, a BMS12/200 and a MPPT75/15 with 2x110W solar panels. Due to the current cold weather conditions (<5°C), the battery and the BMS shutdown the battery charging.
Whenever there is sun available, the voltage on my BMS load and the MPPT battery output increase to ~17V. I assume this is due to the battery shutdown for charging. As soon, as the battery is open (>5°C), the voltage decreases to a normal level.
Is that expected? I thought the MPPT will reduce somehow the voltage when there is no charging in progress.
Why I am asking the question? If put the MPPT battery charging minus on the BMS load pin, where all my other load is also connected to. Now I have ~17V on all my devices, as long as the battery is shutdown. Is my design correct or do I need to change something?