Battery Fuse Blows When Plugged Into Shore Power

The fuse that is blowing is not the fuse that is located in the breaker box in the trailer. That fuse is a 30 amp fuse, and the reverse battery protection fuse is 40 amp. The fuse that I am talking about comes right off of the battery wiring and is in the front of the trailer in the underside (a few inches from the tongue). The trailer is brand new and the fuse that was in there when I originally discovered it was a 20 amp fuse.

The converter is a WFCO. Model- 84435-P
Panel Input- 120 Vac 60 Hz 30A
Converter Input- 105-130 Vac 60 Hz 7.5 A 600W
Converter Output- 13.6 VDC 35 A

I do not know what gauge the wiring is.

Thanks for all your help!