I have at 15k Dometic rooftop AC on my 5th wheel and using a 3500 watt generator. The AC seems to surge or cycle fast and trips my generator to overload. It did the same thing to my buddy’s generator when we hooked it up to his. We hooked his AC up to my generator and it worked fine. When I connect my camper to a direct power source, the AC works but I can hear it cycle too fast sometimes. I always use the 30 amp cable and not an extension cord. What could be making the generator trip?