macdaddy1111 has the set up. The 30A on the wall is 120VAC and runs from one single pole breaker in the panelboard. In fact this is the best way when a park only has 30A on the pedestal. One A/C with a few other items only.
What Bob has is old. Old. Don't use it, remove it. BUT you can repurpose the cable but need to replace the receptacle itself and then change the wiring in the panelboard to match. Written on the cable should be the wire size and # of conductors.
Search for NEMA plugs charts on the web and you can see the multitude of stuff that is out there.
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