I wired my boat for AC but I have it rigged for shore power or generator as well as for an inverter
. One only has to make sure that it is set up so that they do not all operate at the same time.
The shore power is connected through an isolating transformer, so that nothing on the boat is earthed to shore although the third pin connections are all made and connected to the point where the overload fuses/switches are situated. These are just inside the deck house on the inside of the deck house side, just below an all-weather inlet. The shore power also connects to the battery charging system for the twelve volt system which runs the lights
as well as charges the batteries. This system is also connected to the solar array and the wind generators when they are on board. Blocking diodes are in series with the wind generator.
As for the actual AC wiring, I use ordinary heavy power wire and run it in a PVC tubular conduit. The 12 volt system is entirely separate from the AC and uses different cable and runs in different types of conduit--so there is no chance of a mix-up. They run in their separate ducts--the 12 volt system uses ducts which can be opened to admit more wires--and often contains other circuits. The AC mains power must always be separate and enclosed in a conduit. Never use clips to fasten the wiring unprotected by a conduit it to a bulkhead or stringer.
So--I have a lead which I plug in to the shore power ship's inlet when I use the AC generator and each of the power outlets inside the vessel is fused separately through a box of circuit breakers. When I use the inverter
it is also connected through the same system--via a special cord. It may sound unnecessarily crude using cords to plug in to the shore power inlet--but is is pretty fool-proof.
So--marina power to isolating transformer to AC inlet in dog house.
Battery to inverter
to AC inlet in wall of doghouse.
Generator to AC inlet in Doghouse. Everything in boat is double-insulated and isolated--the earth for5 the AC is NOT connected to the DC earth system. It is not connected to anything--since the isolation transformer separates it from the AC mains supply and it is no longer part of the shore power earth system.