Power loss

Not a lot of information there for anyone to be able to give constructive advice 

As said - need more info - make / type of caravan/ motorhome.

You should have an RCD main switchboard somewhere which should include both rcd fuse units and possibly also a bank of auto type fuses

Check these in first instance and come back with more detail if to no avail

Not sure what you have not working but each item will have its own fuse so check them all. There will also be a master fuse which might also have gone. If it is not the fuses then more information is needed to go further.