you will get different opinions to your questions. i do not know you specifics so what i have to say is based upon my experiences.
the remote switch for the inverter is simply an on/off switch for the inverter. nothing more. you need to turn the inverter on when you want it to make ac power from the dc batteries. a prime example of when you might want to do this is when you are traveling with a residential refrigerator and you want it to operate while traveling. if you are on shore power most inverters sense this and go into standby mode and let shore power be the power source. at this point the inverter is using minimal power just to stand by. many will say just leave the inverter on all the time.
you want the battery switch on when connected to shore power so that the converter can send power to the batteries to recharge them. you want it off when you are not connected to shore power so the batteries do not drain down.
i do not have solar but you do. many people say they can leave the battery switch on and let the solar panels recharge the batteries.
without solar it is very common for the battery switch to NOT remove all loads from the battery. these remaining small loads will still drain the battery over some time. many people, myself included, have installed out own disconnect switch on the batteries to remove all loads from the batteries while in storage. my trailer has been in storage for 6 weeks now with all loads disconnected. i went over this weekend and they were still fully charged. if i had not put my own disconnect switch on the batteries would have been dead over this time in storage even though i used the factory installed switch to disconnect the batteries.
2015 cardinal model 3825fl
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