You are talking about two different pieces of equipment....the IN
verter produces 110v AC current from the 12v
DC batteries. Not all Airstreams come with a built-in IN
All Airstreams have a CON
verter... The CON
verter takes 110v AC power (via shore power or a generator) and produces 12v
DC power for the 12v
systems, as well as charging the batteries with a 12v charge. There are single-stage and three-stage CON
verters. You'd have to check on your particular unit to determine whether it is a single-stage or a 3-stage CON
In newer Airstreams all the lighting is 12v, but the 12v lighting system is given 12v either from the batteries (when not connected to shore power) or from the CON
verter when plugged into shore power or a generator.
Our rig happens to have a factory 600w IN
verter... which can be handy but it is not essential. We use it for charging laptops and electronics and using the TV when we are camping without shore power or generator. When our 06 was built they were putting single-stage converters in them, and that's what we have to this day, since it has not malfunctioned and has not been replaced. When we have shore poser we simply plug the computer and TV into the regular 110 outlets like we would at home.