(disregard, i re read and think the OP wanted a plug outside at a table)
Your camper does not have a 120 plug outside it?
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I assume.... the OP is at a camp ground that only offers a 120v standard plug, and wants to plug the camper into it. (like we do at our houses to prep the camper)
At state parks here... they have limited electric sites, usually for disabled people, that have 120v plugs, and NO round camper plugs.
The plugs at those sites are so the disabled can run basic medical devices. The ones I see up here are breakered at 15a.