T&T: 15 amp Y adapters

[bob england]

The 15amp/125 volt twist lock items are relatively inexpensive at the big 
box home stores. You could wire a pair of them into a weatherproof box with 
a 30 amp receptacle. If both 15 amp services are on the same leg and have 
seperate breakers (unlikely) you could pull 30 amps at 125 volts, with a max 
of 15 amps on either leg. They would probably be 2 seperate circuits of a 
125/250 volt service, in which case you would need a 15 amp 4 wire 250 volt 
receptacle in your weatherproof box, and a male plug to match. If you really 
need 30 amp/125 volt service from two 15 amp 125 volt split phase 
receptacles you'll need a transformer in your boat. Have we discussed this 
befor ?