It's on the blade at the 4:00 position on the black and yellow pics below. What would cause this? Here's the detailed background FYI.
I mentioned a while back that my Progressive Industries 30A external unit had some melting on one of the blades at the pedestal. It had shut off 5 times in the first couple hours. The campground claimed the pedestal was new (it looked brand new to me) and he tested the pedestal with a volt meter and everything seemed fine. He said the problem was with the unit not being able to lay flat against the pedestal which caused a poor fit which would have caused "arcing" and the melting and would have shut off the Progressive like a fault. See pic below (black plug). The only fault code on the Progressive was for low voltage.
So I ran to the nearest RV place and bought the only alternative they had in the shop - a Camco version which I don't like or trust nearly as much as the Progressive. I used it the rest of that weekend - bungee corded tightly to the post. It only shut off once the rest of the weekend (AC on a lot) which I attributed to a low voltage condition in the park (this unit has no codes to tell you why it shut off - and I failed to check the plug on the Camco at the end of that weekend so I don't know if it was damaged then).
This weekend, I was using the Camco - no power problems - and it laid perfectly flat against the pedestal - though I bungeed it to the pedestal anyway. When I was packing up, I noticed the same blade had melted some. See pic below (yellow plug).
My grey power cord for the trailer (which plugs in to these units that then plug in to the pedestal) has no such damage (see pic below - grey plug).
Is there something wrong with my AC that's causing this melting? At $300 a pop, these surge protectors are no longer feeling like "cheap insurance" and before buying another, I'm wondering if I have something wrong with my trailer?
Wide open to your thoughts! Thanks.