- On a default airplane, the battery charger WILL keep the battery charged
- On an airplane that is supported by GSX and is flagged to use a custom electrical system, like most of the high-end planes on the market, in order to be sure not to interfere with the simulation (which usually have its own custom variables and a custom simulation), the battery charger is disabled, so the message is telling you that.
- SOME products, like the FS Labs Airbus, recognize the GSX power unit, and automatically enable External power when the GSX jetway connects so, we are still not touching the airplane system, but the airplane can keep itself charged just the same.