George
You said:
Hi Miriam
Are you sure about The Grounding being a stake in the ground, I find that this is the biggest mix up, when an electrician talks ground he is usually just refering to the chassis earth and not actually refering to a ground stake.
What we are saying is to be sure the place you are plugging into is correctly grounded to the ground! Europe may not have a problem with public facilities not being right but we might. I think when you say earth your are saying the same thing we are.
I don't know a single electrician who will tell you to ground 120 to the chassis (frame of a car or trailer). When you add the word earth I am not sure if that changes what I think.
I would not ever ground my camper's 120 to my trailer or car and not be sure my source was right. If you don't have three plugs on your equipment adding an adapter may not help you. Just me. I don't want to recieve the Darwin award.
Disconecting the main, I am not sure is hard. Plug in, plug out. However copper is very expensive and driving a ground rod in 4-6 feet is more trouble than it is worth. Test for a good ground instead.
12v dc will not kill you. Cheap 120 pumps fail all the time.
Just my opinion.
Miriam