Hi IanP I am 6 months into a solar build and still learning along the way!
the way i went was to identify the electrical equipment that was connected and used most or all of the time, in my mind it was pointless to build a system to incorporate the energy load of a toaster that burns 2 slices of bread once a day ::)
What i will say is that its much easier to build a system that will automatically provide mains charge voltage to the Backup Batteries if the voltage drops below the required battery voltage, this would mean you dont have or need to switch between mains or inverter mains, you only need to connect the circuits that are solar powered to one D.B. that is powered via solar/mains augmented battery charge (At Night on the EV Tariff) This is the route i am going on the next stage to reduce the day time cost if the sun is not out to play :-)
I am still doing the math but its a No Brainer in my mind as i can charge the Batteries over night "IF" they need it at 1/3rd the cost and use they energy the next day when its needed.
My system at the moment kicks in the chargers when the battery voltage drops on a dull day but even then the solar panels do add charge voltage too, its kinda a balance of all things :-) Using the EV tariff will let me chose to charge up the battery based on "IF" its gonna be a Dull Dark Day with just one press of a button based on next days weather forecast ::)
Hopw this helps
the way i went was to identify the electrical equipment that was connected and used most or all of the time, in my mind it was pointless to build a system to incorporate the energy load of a toaster that burns 2 slices of bread once a day ::)
What i will say is that its much easier to build a system that will automatically provide mains charge voltage to the Backup Batteries if the voltage drops below the required battery voltage, this would mean you dont have or need to switch between mains or inverter mains, you only need to connect the circuits that are solar powered to one D.B. that is powered via solar/mains augmented battery charge (At Night on the EV Tariff) This is the route i am going on the next stage to reduce the day time cost if the sun is not out to play :-)
I am still doing the math but its a No Brainer in my mind as i can charge the Batteries over night "IF" they need it at 1/3rd the cost and use they energy the next day when its needed.
My system at the moment kicks in the chargers when the battery voltage drops on a dull day but even then the solar panels do add charge voltage too, its kinda a balance of all things :-) Using the EV tariff will let me chose to charge up the battery based on "IF" its gonna be a Dull Dark Day with just one press of a button based on next days weather forecast ::)
Hopw this helps