The best protections against RV power problems is an outlet checker (Home Depot <$7) and verifying that you have good connection. In more years of RV'ing than I care to remember, the most common problem I have encountered when hooking up is loose 15 amp outlets, some where the plug won't even stay in place. To counter that I carry a 15 to 30 amp adapter and always use the 30 amp outlet when it is available. The 20 amp breaker in my Intellipower panel still protects my rig. BTW: If you still have a molded plug on your power cable, if it even gets warm during use, it's time to change to a new "dead front" plug. Molded plugs are notorious for developing loose internal connections over time. Loose connections inside = heat and spikes.