Here is a neat wiring diagram showing the 30A to 50A adapter in use. Like said above all circuit will have 120VAC power applied but you will only have a 30AMP source of 120VAc power. Note the two HOT LEADS are tied together in the Adapter.
The 50-AMP service actually applies 50A service for the two legs totaling up to 100AMPs...
So you can see from this you will really have to watch what you will be using at the same time on both circuits... Obvisouly the Air Conditioners and the High wattage Microwave unit will be something you may want to not use at same time with other 120VAC appliances etc...
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Roy Ken
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