[jcurtis934]

An electrical management system constantly monitors the incoming power and isolates the rv from line one, line two, or both depending on the fault. The progressive unit also logs the fault and displays the code for it until you reset. I have had no ground issues, low power on one line or the other, high frequency once in smokey moutains, high power on both due to a close lightning strike that took out power in campground in smokey mtns. Someone doing maintenance at a campground can easily reverse wiring when replacing a 50 amp outlet if they are not paying attention and don't check their work. A surge protector does nothing except protect against very high fast voltage conditions that might occur due to a lightening hit in the area that bleeds onto the power lines. When this happens the devices in the unit are weakened or burnt up.