Forget you ever heard of 100 amps available. I'm just gonna leave that there. You should also. Your choices are 50 amps 4 wire 120/240 volts and 30 amps 3 wire 120 volts. If you rig has a 50 amp service then you have 240 volts delivered to you circuit breaker box. That is where it stops. You cannot access 240 volts there. 120 volts 50 amps to the left of the main and 120 volts 50 amps to the right of the main. You have two 50 amp 120 volt legs to use. BUT if you exceed more the 50 amps on one leg the 50 amp main will trip. There are dog bone adapters available but you will only get 120 volts out of them. 50/30 and 30/50. Also 30/20. If you plug your 50 RV into a 30 amp outlet using a dog bone you will only get 30 amps.
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