Do you hit inverter shut off much while camping or just when on solar charge while the RV is being stored? I don't think there's much issue cranking back the voltage set point even as far at 13.8 in a situation where the batteries start out every day charged (still good to get a periodic overcharge from the equalize function though).
I wonder if they behave the same when charging in a real boondocking situation, coming up from a real world discharge. My guess is they will not jump up voltage as badly because their resistance is lower, and the extreme nature of these jumps is a fully charged battery phenomenon. Certainly I see my batteries jump up more recovering from a quick load when fully charged, even with no charger at all on them.
If so, a setting for the charge controller while in storage (with an even lower voltage than you have it set to now) and a more normal one for camping might mitigate the problem all together, if it's not too inconvenient to send new settings down.
Jim
