Hello to the community! I work on an installation that there are 3 Phoenix inverters.. 1600/3000/5000va for different applications.
All of them have connected an RCBO at the output but the 1600va has also a bridge between PE-N before the RCBO.
Its the first time i see this on victron off-grid installations and i spent some time to find out what is going on and if it is needed.
I could not find any documentation at the victron provided manuals but online i found out that if this bridge does not exist, the RCBO does not operate correctly in case you have an electric shock or a short between PE-N.
If there needs to be a neutral earth bond or not is determined by the earthing system you use.
Even if you are offgrid, you still need to choose and implement one.
Some require neutral-earth bonds, some dont. TN-S is probably regarded as the best overall system, but of course theres arguments to use another system in a specific situation (on a boat for example).
Without a neutral earth bond, there can be no current flow from over the earth conductor, rendering RCDs/RCBOs useless. (Yes theres a counterargument that without a neutral earth bond you cant even get electrocuted in the first place, but only in certain conditions. Overall the benefits outweigh the negatives in TN-S).
A general overview of different earthing systems that are in use today is for example this video
