I bought one of
these. They're pricey (about $300) but less than the cost of a microwave. Comes in 30 or 50 amp flavors.
When I hook up I never think about power, just plug in to pedestal and about 30 seconds later I can hear a loud clunk as the relay activates, letting power go into the rig.
Funny off track story... The only time it has ever 'saved' me was one time when I tried to run the rig from my Honda generator. I didn't have the neutral connected to ground at the gen set and it knew it and wouldn't pass power to rig. I was po'd 'cause I really wanted coffee at the time but it was sure gratifying to see it work. I've never had it 'work' again to save me after a year of full timing so it makes me feel good (sorry) to hear of people encountering bad power.
That's the way it is with insurance; you don't need it and can't afford it until you need it and it's priceless.