A 30 amp Recreational Vehicle plug must actually be used with a 30 amp breaker. You could als plug it into a 15 or 20 amp breaker, but you run the risk of damaging your RV if you utilize more than the ranked power the circuit/outlet has been designed for.

What size breaker do I need to run a camper?

Answer: A 50 amp RV outlet requires a double pole, while 20 and 30 amp outlets require a single pole breaker.