I too got one for the first time this year never had an issue at a campground but our campers 30 plus years ago did not have as many electronics.
No converter, no radio, no microwave, no electric side to a water heater, and the list goes on.
The 12V system was totally a separate system. There were 110V and 12V lights separately, some campers even had gas lighting. No tank sensors, No tanks Heaters, The good old days
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