One often over looked problem at campgrounds are worn out shore power outlets from many campers plugging in over time and wearing out the connections. 50 Amp units are the most likely to suffer damage from the common prong (The center flat plug terminal) wearing out. This bad connection will cause 220 volts to feed into the RV, causing major electrical damage, There are many factors that can also cause surge problems as well. A surge protector is expensive, but it is very economical expense to pay now to avoid major expenses without this device. Always inspect your cord for worn or black terminals. Clean or replace as necessary. Notify the campground when your terminals are discolored, because it is generally caused by a worn out shore power receptacle.java script:add_smilie("","smid_10")