What PAWPAW said. I have a surge guard and after plugging in to shore power it delays for about 2 minutes while it checks the current.
I full time so I move my rig all the time.
I also shut down both AC units as well as the water heater before breaking camp to go to another CG. After moving, hooking up power (first), water, sewer and sending out the slides I then go inside and turn on the AC unit(s) about a minute apart, after checking to make sure the microwave is blinking '00:00'. The water heater gets turned on later.
I'm no electrician but it just seems like a bad idea to have everything already 'on' when plugging in to shore power. Would be a pretty good jolt to the system.