Originally Posted by seevee
tell me about that adapter. Seems like you'd have to monitor power carefully.
Now, if you plugged one leg of a reverse y into a 30 amp supply, you'd get half of the power in the boat, i.e. One leg of the 50a, is that correct? So, if one used that, they could just pick the leg that would give them what they wanted.
I'd like to run the ac on dehumidify and the charger with that setup.
But your adapter has me thinking... Do you have a part number?
Here are 3 of the most common adapters to use on a standard 50 amp 250 volt shore power cord.
The top one plugs into a standard house outlet (125 volt 15 amp). It ties the 2 hot conductors in your shore power cord together and gives you a total of 15 amps at 125 volts. Don't use this adapter if you have any 220 circuits in your boat panel! These might be a stove, air conditioning, water heater or clothes drier. While not a hard and fast rule, most boats under 50' that have the 50 amp 250 volt shore power cord, don't have any 220 volt circuits. I use this cord when I'm in the boat yard or on a friend's dock to maintain the battery bank, refrigerator, and maybe one air conditioner.
The middle adapter is the same as the top one only it has a 30 amp plug. I can live comfortably on this one if little or no heat or air conditioning is required. Don't try to run an electric stove, water heater and air conditioning at the same time. Same limitations for 220 volt circuits apply.
The bottom one takes two 30 amp plugs and gives you 30 amps on the 2 positive conductors in your shore power cord. It will also work with 220 volt circuits on your boat. It has a monitoring circuit and disconnects inside the junction box. The disconnects don't close until you have 220 volts from the two 30 amp plugs combined. This requires that the two 30 amp plugs be on different phases and the voltage is higher that 215 volts +/-. Sometimes you will come across two 30 amp receptacles on a power pedestal on the same phase, so it won't work. Sometimes you will be on a dock with a 208 volt tranformer, so it won't work. Sometimes you will be at the far end of a long dock on a hot or cold day when lots of heaters or air conditioners are running, dragging the voltage down below 215 volts, so it won't work.
The frustrating part is that your boat may work fine on 208 volts from the pedestal outlet (mine does), but this adapter won't let you use the two 30 amp outlets on the same pedestal that combine to 208 volts.
Marinco part numbers:
Middle: 117A or 111A