Just a question....Can I start and run the generator to "exercise" it and to re level my coach (in winter storage) while plugged into shore power...or do I have to disconnect the shore power first?
Should be ok. IIRC the transfer switch should default to shore power so even with generator running your coach will stay connected to shore power.
But you should put a load on the generator, heater, a/c, microwave, etc. while it's running after shutting off shore power.
The general recommendation is to unplug first whenever possible, due to arcing damage at the contacts of the transfer switch relays.
There are previous discussions on the forum if you search.
Every month, if I haven't had reason to use my generator, I turn off any heavy loads and fire it up and set a 1-hour timer. Once it's settled in and the transfer switch has disconnected me from the shore line I turn the heavy loads back on. Summertime: air conditioners. Wintertime: heat strips in the air conditioners, electric space heater, make some coffee and microwave some oatmeal.