James is right. Everything is wired at the batteries for 24volts. Panels are wired for 48volts, then split off to 24v at the controller for storage at the batteries.
As shown, the generator does not kick in at a certain voltage. It would need a relay and auto start system. Although that may be there. Schematic also doesn't show any monitoring unless it's built in the systems.
Really nice set up and would run a good deal of stuff in a off the grid situation. Downside, it would take up a lot of space storing batteries and panels that may be needed for other transport storage. Thanks for putting that up DG. I do like it and think it would be great to use as a emergency communcations support vehicle.