Yes, I know the rating of 12 guage and I was very surprised as well. This IS the way it came from Barth! I have the build sheet! With two roof air conditioners, you need at least 5000 watts. I am sure that is what they were thinking that with two legs of 120 VAC each leg would not see over 20 amps

The gen set will power the entire coach, A/C and microwave together plus the battery charger (75 amp)
The breakers (a pair) on the gen set 40 amps each! and the breakers on the main bax in the back are 50 amps.

Added: the +12V cable from the vehicle batteries is VERY small also, 4 gauge, this goes over 30 ft from the coach batteries to the gen set, when starting the gen set I see less then 9 volts, I will be installing 00 guage along with some other upgrades while in there. Still have to tackle the low beam headlight issue.

Guess I have to proof read my posts better, I removed that last comment, sounded very bad!