Most of the time I `m not useing power that requires a 30 amp cord
I have removed the onan gen and sold it and use a Honda on a platform on the rear ,in front of the gen compartment, so to power with the honda I put a short piece of 20 amp cord on the existing gen junction box in the compartment to plug into the honda , the 30 amp cord in the power comp remains pluged into the receptical that goes to the junction box
Aside from a little line voltage drop it works good 
If I was in a park and useing the AC I would use the 30 amp cord , but most times I`m useing the honda , or at home just pluged in for battery maintance so I use a household 20 amp cord and throw it into a compartment when I travel
Havent unpluged the 30 amp from the receptical in a long time