Originally Posted by jimmbob
Sorry things are good at house end just when a I was working on trailer sweaty was when I felt the "buzz".
Plugging into the house establishes (assuming the house safety ground system is intact) the trailer frame potential as the potential at the ground rod where the power enters the house. There are many reasons why the potential of the ground at the trailer might be different. Even if there are no faults in the trailer, you could have a potential difference of several volts. Since you are getting the tingle when placing yourself between the trailer skin/frame and the ground near the trailer, you should make voltage measurements to the ground there, not to the green wire.
I still go back to your original post that said you were getting the tingle with shore power disconnected. In order for that to happen, there must be another connection from the trailer to the ground. Without that, any voltage generated on the trailer has no reference to ground and will not cause a tingle. If you don't believe this, put two cars side by side. Measure from the positive post of one car's battery to the negative post of the other car's battery. You will read 0 volts. The most likely ground references are the tongue jack and the TV cable connection. IF you were connected to a campground TV cable system, it's coax shield could have a voltage difference to ground and you might feel that.