Pretty basic that as it gets hot, it pulls more current and trips the breaker. That's, you know, the whole point of a breaker, to trip at a certain current. Current = amps. If it doesn't trip, its exactly what I said, a bad setup.
That is how it is supposed to work but often it doesn't. I've seen 1 RV plus 2 boat fires caused by shore power plugs and lost count of the melted receptacle/cord ends I've replaced. It is why NEC requires AFCI breakers in new construction.
Along with being more durable Smart Plugs also have tempurature sensor that prevent things from catching fire.
The SmartPlug is a revolutionary shore power connections system designed to replace the outdated and problematic twist-type design in use today. And what is a smartplug...