Got the breaker panel finished and wired in. Works great, but the still has voltage potential between earth and trailer. I have now ruled out the entire trailer side of the wiring i think lol. Next is grounding the solar panels/ container.
Have you checked out whether there is a voltage potential between two places on your lot, in the absence of any of your PV wires running between trailer and shipping container? e.g. leakage current from a utility substation or power line?
I assume your system is driving a voltage out to the shipping container, but since one of your questions brought up this possibility, might as well confirm or eliminate it.