A baby cow is called a calf. Adult male cows are called bulls. Adult female cows are called heifers until they give birth; after they have given birth, they are called cows.
As long as there is a fuel supply of natural gas or propane, a well-maintained backup generator will keep running. If the Generac generator is running on propane, with a 500-gallon tank, it should run 24 hours a day for over a week. How loud are they? Generac generators are very quiet.
Generator Size Issue - How Much Wattage? The output on the generator at 120v is around 30amps and only 15amps for 240v. Try using the welder with the 120v plug. I have the Generac 10k generator, it has a switch to turn off the idle down mode and keeps the RPMs up all the time.