the sure way to answer your question is...
unplug and nothing running..and put your volt meter across your chassis battery and read what you have.
then plug your shore power in and read your voltage ...I would do the house and chassis battery ...
there was nothing in the paperwork with my motorhome to let me know whether or not my chassis battery was charging and maintain and / or over charging while plugged into shore power...so many only charge/maintain and boil dry the house battery and the chassis battery slowly drains to dead...
luckily both mine charge and maintain while being plugged into shore power...still keep an eye on battery water..
