Off grid 3 phase with Multiplus 2

Considering going off grid with a 3 phase Multiplus2 config. If one of the Multiplus goes offline does that bring down the whole lot or is it just the loss of one phase?

Yes, any communication failure or failure of one of the multiplus’s would result in all 3 units becoming inoperable until the issue is resolved or reprogrammed to operate without the failed unit