Many circuits in a home are typically rated for a maximum supply of 15 amps. A 30 amp camper will draw considerably more than that, and you risk overloading the circuit and causing a fire.
If you camp out near a home, instead of plugging into the home's electrical system, purchase a voltage-regulating transformer. This regulates the voltage, protects your camper from voltage surges, provides a steady voltage supply and isolates the camper's electrical system from that of the home's.
If the amperage of your electrical system is higher than the rating on the transformer, run an appropriately rated extension cord directly to a heavy-duty outdoor outlet protected by a ground-fault circuit interrupter (GFCI).
