Generally, a Cummins Onan residential home and light commercial standby generator set offers many features not found on portable generator sets, such as a more sophisticated control system, a fully weather protective enclosure, significantly quieter operation, and more capacity so you can power more conveniences. It goes on automatically when you need it and shuts down automatically once main power is restored. It is connected directly to a fuel system and your home's electrical system so you wont have to fill a gas tank or manually transfer power from the utility to the home standby unit.