Hi friends. Electricity is my weak suite but I think my question is easy for you smart guys. I don't want to make an assumption and have it turn out to be expensive

. I'm assuming that if I buy a 50 amp surge guard/power protector (such as
this one) it will still protect me when using the adapter to my plug and plugged into a 30 amp pedestal. I'm guessing it's an "up to" number but I want to be sure. We've only been at this a little over a year and have always had 50 amp campsites. But the one we are heading to in a couple of weeks only has 30 amp hookups. I found a nice list of approximate amp draws that I can use to stay below 30 but I'd also like to know if there is some simple device to plug in somewhere to tell me my draw at a given moment. Thanks in advance for the help. This forum is a gem for us new folks!