As I mentioned earlier the Consumer unit I am using is intended for use in an outbuilding or garage so is better suited to a marine environment as it is IP55 rated and has an RCD fitted.
It has 3 breakers, 6, 10, and 16 amp, the 6 amp will be used to wire in the battery charger, the 10 amp will be for the hot water calorifior, and the 16 amp will be for the on board plug sockets.
I am not an electrician but have some experience with this type of installation, so as always I wanted to confirm that what I was planning to install was going to be suitable and safe and came across an article which had the exact wiring diagram for the plan I was using. (thanks to Colin Shead)
The cable I am using is different from domestic 2.5mm solid core, H07RNF is the most suitable cable to use although Arctic cable is commonly used.
This cable is a little more expensive but is extremely flexible so good for tight spaces and less susceptible to chaffing.
The main difference with a marine installation is that the use of a galvanic isolator is advised, which without getting too technical will prevent electrolysis from destroying underwater stern gear.
The first is where I found the wiring diagram and is an article by Colin Shead, the second is a magazine article with some useful tips.
Marine electrical tips
Shore power installation