I uploaded at photo at https://groups.yahoo.com/neo/groups/amelyachtowners/photos/albums/1556459704/lightbox/708950431?orderBy=ordinal&sortOrder=asc&photoFilter=ALL#zax/708950431
The photo will show you how to change the compressor speed by moving 1 of the thermostat wires to another terminal.
Supposedly, a slower running compressor is much more efficient. It runs more but does not work as hard and burns about half the amps. It seems to be working for me. I moved the thermostat wire from the terminal marked 200 LITERES to the terminal marked 130 LITERES, which reduced the compressor speed from 3,000 to 2,000RPM. When I made the change the amps reduced by almost half while the fridge was running. It does run more, but seems to perform better and more efficiently.
I believe this may apply to some Santorins and possibly some 54s. If you have the E51600 Frigoboat Power Module, it applies.
I would be interested in the experience of any other folks trying this. On a Super Maramu 2000, the E51600 is visible when you remove the wood kick plate in front of the fridge.