Dual dock power input 120/240

[cbaysailor]

I currently have a 240vac 50a input to my boat.

Would like to add alternate 120vac 20a or 30a input, for occasional cases where 240 vac might not be convenient. This would be wired through an A/B breaker that would replace a single breaker within 10' of the genset.

I know enough to not plug in both dock lines at the same time or draw from two sources at the same time, but are there any physical interlocks needed in addition to the two A/B switches on the boat which allow only one of the 3 sources (120 line, 120 genset or 240 line) to be used at the same time?

Thanks

cbaysailor

[Auspicious]

Consider using an adapter instead. West Marine (http://www.westmarine.com/webapp/wcs/stores/servlet/westadvisor/10001/-1/10001/ShorePower.htm) has a nice chart of the alternatives. A 30A 125V to 50A 125/250V adapter will allow you to use your current shore power cord up to the power pylon where you can fit the adapter. Less work, less gear to carry, less chance of error ...