Ok on 50 A but not on 30 A

was_butnotnow wrote:
I have HitchHiker 5th wheel with only one AC. Trailer is wired for 50A but I can use an adaptor to hook to 30A since I don't need 50A. I replaced the 50A male plug and got a new 30A adaptor and now my one and only AC and fridge will only run when the straight 50A plug is used. With the 30A adaptor I have AC lights but no fridge or AC. Any ideas what is wrong. Volage looks good with meter as far as I can tell. It's this way in now two different RV parks.

The loads in your RV are split between the 2 hot legs. The 30A adapter is supposed to power both of those legs from its single hot input pin. It seems like a bad adapter to me or one that is only designed to power one side of the 50A.

Can you check the voltage coming out of both hots of the adapter with the RV unplugged?

Better yet is to check the voltage inside the RV panel with it all connected up. There may be voltage on the adapter until you load it a bit if there is a really weak connection inside the adapter.