I am restoring an old USCG boat (I am posting numerous questions relating to this project). The native electricity for the boat is 400-480v 60 cycle three phase. The native electricity goes to a main panel and supplies a number of pieces of large equipment. Transformers then step the voltage down to 120 single phase and supplies house panels. There is no battery system. There are a couple of very large and very loud generators producing the native current. I would like to greatly reduce the power needs through conservation and add much smaller power alternatives for less power demanding uses. My idea is to add an independent circuit for the wheelhouse that is essentially an uninterruptible power supply for the mission critical systems. I'm thinking of using a Victron Multipass. I am considering two alternatives with the other power needs. 1) The first is to maintain the existing system and have a new generator (small, anchor generator) and battery system to supply the native electricity and leave the existing system in place. All the equipment would technically be hot but the secondary sources would not be sufficient to run the big equipment for long. 2) The second alternative is to feed into the 120v panels with a transfer switch. This would handle the hotel functions. But, there would be no power to the heavy equipment. Both systems require the big generator to make use of the heavy equipment. Alternative 1 may provide momentary use of the big equipment. Btw. My use is to remain on the hook most of the time. So, shore power is a consideration but it is not a driver for the decision. Any comments appreciated. At this point, I am looking for general direction.