I'm trying to install an outlet for my RV. My current one only needs 30 Amps, which is simple to do, just install a 30amp breaker and use wire big enough to handle 30 Amps. However, if I'm going to the trouble to do this, why not install 50 Amp service instead, in case I ever upgrade RVs... The trouble is that I'm not sure what the 50 Amps really is. Since it has 2 source pins and 1 return pin (plus ground), I obviously need 2 breakers. But is it 50 Amps each leg, or 25 Amps each leg? Do the 2 legs need to be out of phase, in phase, or does it matter?