On post #5 photo, unfortunately dark but can be enlarged and seen better, I think there are two 15-amp breakers on the right. Believe they are related to the inverter.
Thought this was for the solar, but went to look to double-check & it isn't. Searched & found a label ...it is a "load center".
Load center = load centre = breaker box = distribution panel
Lots of terms for the same thing. In this case, is appears to be the point where all of the electricity from the inverter (or from the shore power plug-in when available) is distributed to the two circuits which can run on inverter power.
I am pretty sure that we were told that the inverter had two 15-amp breakers which is what is on that, so we took that Siemens to be for the inverter. I believe that there is also another Siemens piece of equipment.
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Cathy. Floating Cloud
"Live in the sunshine, swim the sea, drink the wild air.... "
Emerson