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The plug that looks like a dryer plug, does it have 3 pins or 4?
Let me know so that we can continue.
Ok, just so that I understand, what do these breakers feed? Lights? Receptacles?
How is your AC and the heaters going to work on 120V?
Also, 50A at 240 is 12.5KW How do you plan to run that on an extension cord?
Ok, that can be done but there are too many variables here in order for me to help in a timely manner.
I am going to opt out of this question which will allow other experts to chime in.