If this was me and my trailer this is what I would do
the first thing to suspect is a ground fault issue. turn the trailer off and un plug. now reset the house breaker. plug in trailer does the house breaker trip?
turn off everything the converter is powering and turn off any breakers and pull fuses keep them in order. now if I turn on converter does the breaker trip?
if not i turn on on the breakers in the trailer and see if the house breaker trips.
do the same on the 12 volt side and see when the house breaker trips. then at lease I will know where the fault is. and where to look for repairs.
or plug the trailer in to a non GFI circuit. and the non tripping circuit will probably go away. when I started swapping in led lights
I had problems with the lights
as several of the lights
were wired backwards swapping hots and grounds. 12 volt lights
can tolerate this but leds are polarity sensitive and will not accept a cross wire.
if you are not comfortable with working with electrical
seek help from a professional. I am not a professional and do not profess to be.