Simple answer DON"T DO IT. Never plug in or unplug from the power supply with the circuit breaker on the pedestal on. It will cause damage to the connectors on your plug and in the receptacle on the pedestal. This will increase resistance and cause added heat at the plug. I have helped change plugs that had gotten nearly hot enough to catch fire. now this doesn't happen on the first time but is calmative. In reality you might see discolored spots and rough areas from arcing the first time.
When you are looking for a surge Guard this is the one I recommend.https://www.amazon.com/Surge-Guard-34830-Portable-Display/dp/B00T36Q7R2/ref=sr_1_4?ie=UTF8&qid=1520813283&sr=8-4&keywords=surge+guard+rv&dpID=31USiGI2u7L&preST=_SX300_QL70_&dpSrc=srch
Do not buy the "entry level" ones. This one will save you from bad power as well as low and hi voltage.
Low voltage does as much or more damage than a hi spike. On the first trip with my current coach I was trying to get buy with out a Surge Gard. One low power event cost me a circuit board for the washer. The Surge Guard would have been cheaper.
Where are you going on your first trip?
Bill