Hello there!
I would like to propose a game for Victron experts and enthusiasts who are reading this post. Let's imagine we have a typical PV system with panels, batteries, an inverter charger, loads and the presence of the utility grid. If, at some stage, we want to keep the present system (which is not too old, and its size is not small, not too large) and add a second system of similar size or even larger than the first one, what variants or possibilities would be the most optimal/advisable or more advantageous? Which ones would be valid, but not advisable? Which ones are not technically possible? I know it is a bit of an open question, but it would be interesting to read all opinions. Please take it as a game.
As a general guideline the aim is to increase the size of the system, while keeping the original one. Loads should still be supplied in the case of grid failure. Excess energy can be fed or not to the grid (up to you).
If you like you can give opinions based on the following diagrams (I believe they are all self explanatory, but if not please ask). Number 1 is the original system. For the others, in red the system I believe is not possible technically. In purple a system I believe has little benefit, but still possible. In green all other viable possibilities. For these, subindexes 1 and 2 do not mean 'original' and 'new' inverter - please feel free to place every inverter/charger in the position you like.
I know its obvious, but here you have the meaning of each letter (panels, charge regulators and grid-tie inverters are not depicted in the diagrams, in order not to add complexity, but both AC and DC coupling can be considered for any or both of the inverter/chargers).
U stands for Utility grid.
I stands for Inverter/charger (Multi, Quattro)
L stands for Loads
B stands for Battery
And of course please let me know if I am wrong in any of my assumptions!! :)
Cheers!